- java.lang.Object
-
- java.awt.Component
-
- java.awt.Container
-
- javax.swing.JComponent
-
- javax.swing.JList<E>
-
- Type Parameters:
E
- the type of the elements of this list
- All Implemented Interfaces:
- ImageObserver, MenuContainer, Serializable, Accessible, Scrollable
public class JList<E> extends JComponent implements Scrollable, Accessible
A component that displays a list of objects and allows the user to select one or more items. A separate model,ListModel
, maintains the contents of the list.It's easy to display an array or Vector of objects, using the
JList
constructor that automatically builds a read-onlyListModel
instance for you:// Create a JList that displays strings from an array String[] data = {"one", "two", "three", "four"}; JList<String> myList = new JList<String>(data); // Create a JList that displays the superclasses of JList.class, by // creating it with a Vector populated with this data Vector<Class<?>> superClasses = new Vector<Class<?>>(); Class<JList> rootClass = javax.swing.JList.class; for(Class<?> cls = rootClass; cls != null; cls = cls.getSuperclass()) { superClasses.addElement(cls); } JList<Class<?>> myList = new JList<Class<?>>(superClasses); // The automatically created model is stored in JList's "model" // property, which you can retrieve ListModel<Class<?>> model = myList.getModel(); for(int i = 0; i < model.getSize(); i++) { System.out.println(model.getElementAt(i)); }
A
ListModel
can be supplied directly to aJList
by way of a constructor or thesetModel
method. The contents need not be static - the number of items, and the values of items can change over time. A correctListModel
implementation notifies the set ofjavax.swing.event.ListDataListener
s that have been added to it, each time a change occurs. These changes are characterized by ajavax.swing.event.ListDataEvent
, which identifies the range of list indices that have been modified, added, or removed.JList
'sListUI
is responsible for keeping the visual representation up to date with changes, by listening to the model.Simple, dynamic-content,
JList
applications can use theDefaultListModel
class to maintain list elements. This class implements theListModel
interface and also provides ajava.util.Vector
-like API. Applications that need a more customListModel
implementation may instead wish to subclassAbstractListModel
, which provides basic support for managing and notifying listeners. For example, a read-only implementation ofAbstractListModel
:// This list model has about 2^16 elements. Enjoy scrolling. ListModel<String> bigData = new AbstractListModel<String>() { public int getSize() { return Short.MAX_VALUE; } public String getElementAt(int index) { return "Index " + index; } };
The selection state of a
JList
is managed by another separate model, an instance ofListSelectionModel
.JList
is initialized with a selection model on construction, and also contains methods to query or set this selection model. Additionally,JList
provides convenient methods for easily managing the selection. These methods, such assetSelectedIndex
andgetSelectedValue
, are cover methods that take care of the details of interacting with the selection model. By default,JList
's selection model is configured to allow any combination of items to be selected at a time; selection modeMULTIPLE_INTERVAL_SELECTION
. The selection mode can be changed on the selection model directly, or viaJList
's cover method. Responsibility for updating the selection model in response to user gestures lies with the list'sListUI
.A correct
ListSelectionModel
implementation notifies the set ofjavax.swing.event.ListSelectionListener
s that have been added to it each time a change to the selection occurs. These changes are characterized by ajavax.swing.event.ListSelectionEvent
, which identifies the range of the selection change.The preferred way to listen for changes in list selection is to add
ListSelectionListener
s directly to theJList
.JList
then takes care of listening to the the selection model and notifying your listeners of change.Responsibility for listening to selection changes in order to keep the list's visual representation up to date lies with the list's
ListUI
.Painting of cells in a
JList
is handled by a delegate called a cell renderer, installed on the list as thecellRenderer
property. The renderer provides ajava.awt.Component
that is used like a "rubber stamp" to paint the cells. Each time a cell needs to be painted, the list'sListUI
asks the cell renderer for the component, moves it into place, and has it paint the contents of the cell by way of itspaint
method. A default cell renderer, which uses aJLabel
component to render, is installed by the lists'sListUI
. You can substitute your own renderer using code like this:// Display an icon and a string for each object in the list. class MyCellRenderer extends JLabel implements ListCellRenderer<Object> { final static ImageIcon longIcon = new ImageIcon("long.gif"); final static ImageIcon shortIcon = new ImageIcon("short.gif"); // This is the only method defined by ListCellRenderer. // We just reconfigure the JLabel each time we're called. public Component getListCellRendererComponent( JList<?> list, // the list Object value, // value to display int index, // cell index boolean isSelected, // is the cell selected boolean cellHasFocus) // does the cell have focus { String s = value.toString(); setText(s); setIcon((s.length() > 10) ? longIcon : shortIcon); if (isSelected) { setBackground(list.getSelectionBackground()); setForeground(list.getSelectionForeground()); } else { setBackground(list.getBackground()); setForeground(list.getForeground()); } setEnabled(list.isEnabled()); setFont(list.getFont()); setOpaque(true); return this; } } myList.setCellRenderer(new MyCellRenderer());
Another job for the cell renderer is in helping to determine sizing information for the list. By default, the list's
ListUI
determines the size of cells by asking the cell renderer for its preferred size for each list item. This can be expensive for large lists of items. To avoid these calculations, you can set afixedCellWidth
andfixedCellHeight
on the list, or have these values calculated automatically based on a single prototype value:JList<String> bigDataList = new JList<String>(bigData); // We don't want the JList implementation to compute the width // or height of all of the list cells, so we give it a string // that's as big as we'll need for any cell. It uses this to // compute values for the fixedCellWidth and fixedCellHeight // properties. bigDataList.setPrototypeCellValue("Index 1234567890");
JList
doesn't implement scrolling directly. To create a list that scrolls, make it the viewport view of aJScrollPane
. For example:JScrollPane scrollPane = new JScrollPane(myList); // Or in two steps: JScrollPane scrollPane = new JScrollPane(); scrollPane.getViewport().setView(myList);
JList
doesn't provide any special handling of double or triple (or N) mouse clicks, but it's easy to add aMouseListener
if you wish to take action on these events. Use thelocationToIndex
method to determine what cell was clicked. For example:MouseListener mouseListener = new MouseAdapter() { public void mouseClicked(MouseEvent e) { if (e.getClickCount() == 2) { int index = list.locationToIndex(e.getPoint()); System.out.println("Double clicked on Item " + index); } } }; list.addMouseListener(mouseListener);
Warning: Swing is not thread safe. For more information see Swing's Threading Policy.
Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeansTM has been added to the
java.beans
package. Please seeXMLEncoder
.See How to Use Lists in The Java Tutorial for further documentation. Also see the article Advanced JList Programming in The Swing Connection.
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Nested Class Summary
Nested Classes Modifier and Type Class and Description protected class
JList.AccessibleJList
This class implements accessibility support for theJList
class.static class
JList.DropLocation
A subclass ofTransferHandler.DropLocation
representing a drop location for aJList
.-
Nested classes/interfaces inherited from class javax.swing.JComponent
JComponent.AccessibleJComponent
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Nested classes/interfaces inherited from class java.awt.Container
Container.AccessibleAWTContainer
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Nested classes/interfaces inherited from class java.awt.Component
Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy
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Field Summary
Fields Modifier and Type Field and Description static int
HORIZONTAL_WRAP
Indicates a "newspaper style" layout with cells flowing horizontally then vertically.static int
VERTICAL
Indicates a vertical layout of cells, in a single column; the default layout.static int
VERTICAL_WRAP
Indicates a "newspaper style" layout with cells flowing vertically then horizontally.-
Fields inherited from class javax.swing.JComponent
accessibleContext, listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW
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Fields inherited from class java.awt.Component
BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT
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Constructor Summary
Constructors Constructor and Description JList()
Constructs aJList
with an empty, read-only, model.JList(E[] listData)
Constructs aJList
that displays the elements in the specified array.JList(ListModel<E> dataModel)
Constructs aJList
that displays elements from the specified,non-null
, model.JList(Vector<? extends E> listData)
Constructs aJList
that displays the elements in the specifiedVector
.
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Method Summary
Methods Modifier and Type Method and Description void
addListSelectionListener(ListSelectionListener listener)
Adds a listener to the list, to be notified each time a change to the selection occurs; the preferred way of listening for selection state changes.void
addSelectionInterval(int anchor, int lead)
Sets the selection to be the union of the specified interval with current selection.void
clearSelection()
Clears the selection; after calling this method,isSelectionEmpty
will returntrue
.protected ListSelectionModel
createSelectionModel()
Returns an instance ofDefaultListSelectionModel
; called during construction to initialize the list's selection model property.void
ensureIndexIsVisible(int index)
Scrolls the list within an enclosing viewport to make the specified cell completely visible.protected void
fireSelectionValueChanged(int firstIndex, int lastIndex, boolean isAdjusting)
NotifiesListSelectionListener
s added directly to the list of selection changes made to the selection model.AccessibleContext
getAccessibleContext()
Gets theAccessibleContext
associated with thisJList
.int
getAnchorSelectionIndex()
Returns the anchor selection index.Rectangle
getCellBounds(int index0, int index1)
Returns the bounding rectangle, in the list's coordinate system, for the range of cells specified by the two indices.ListCellRenderer<? super E>
getCellRenderer()
Returns the object responsible for painting list items.boolean
getDragEnabled()
Returns whether or not automatic drag handling is enabled.JList.DropLocation
getDropLocation()
Returns the location that this component should visually indicate as the drop location during a DnD operation over the component, ornull
if no location is to currently be shown.DropMode
getDropMode()
Returns the drop mode for this component.int
getFirstVisibleIndex()
Returns the smallest list index that is currently visible.int
getFixedCellHeight()
Returns the value of thefixedCellHeight
property.int
getFixedCellWidth()
Returns the value of thefixedCellWidth
property.int
getLastVisibleIndex()
Returns the largest list index that is currently visible.int
getLayoutOrientation()
Returns the layout orientation property for the list:VERTICAL
if the layout is a single column of cells,VERTICAL_WRAP
if the layout is "newspaper style" with the content flowing vertically then horizontally, orHORIZONTAL_WRAP
if the layout is "newspaper style" with the content flowing horizontally then vertically.int
getLeadSelectionIndex()
Returns the lead selection index.ListSelectionListener[]
getListSelectionListeners()
Returns an array of all theListSelectionListener
s added to thisJList
by way ofaddListSelectionListener
.int
getMaxSelectionIndex()
Returns the largest selected cell index, or-1
if the selection is empty.int
getMinSelectionIndex()
Returns the smallest selected cell index, or-1
if the selection is empty.ListModel<E>
getModel()
Returns the data model that holds the list of items displayed by theJList
component.int
getNextMatch(String prefix, int startIndex, Position.Bias bias)
Returns the next list element whosetoString
value starts with the given prefix.Dimension
getPreferredScrollableViewportSize()
Computes the size of viewport needed to displayvisibleRowCount
rows.E
getPrototypeCellValue()
Returns the "prototypical" cell value -- a value used to calculate a fixed width and height for cells.int
getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous block.boolean
getScrollableTracksViewportHeight()
Returnstrue
if thisJList
is displayed in aJViewport
and the viewport is taller than the list's preferred height, or if the layout orientation isVERTICAL_WRAP
andvisibleRowCount <= 0
; otherwise returnsfalse
.boolean
getScrollableTracksViewportWidth()
Returnstrue
if thisJList
is displayed in aJViewport
and the viewport is wider than the list's preferred width, or if the layout orientation isHORIZONTAL_WRAP
andvisibleRowCount <= 0
; otherwise returnsfalse
.int
getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous row (for vertical scrolling) or column (for horizontal scrolling).int
getSelectedIndex()
Returns the smallest selected cell index; the selection when only a single item is selected in the list.int[]
getSelectedIndices()
Returns an array of all of the selected indices, in increasing order.E
getSelectedValue()
Returns the value for the smallest selected cell index; the selected value when only a single item is selected in the list.Object[]
getSelectedValues()
Deprecated.As of JDK 1.7, replaced bygetSelectedValuesList()
List<E>
getSelectedValuesList()
Returns a list of all the selected items, in increasing order based on their indices in the list.Color
getSelectionBackground()
Returns the color used to draw the background of selected items.Color
getSelectionForeground()
Returns the color used to draw the foreground of selected items.int
getSelectionMode()
Returns the current selection mode for the list.ListSelectionModel
getSelectionModel()
Returns the current selection model.String
getToolTipText(MouseEvent event)
Returns the tooltip text to be used for the given event.ListUI
getUI()
Returns theListUI
, the look and feel object that renders this component.String
getUIClassID()
Returns"ListUI"
, theUIDefaults
key used to look up the name of thejavax.swing.plaf.ListUI
class that defines the look and feel for this component.boolean
getValueIsAdjusting()
Returns the value of the selection model'sisAdjusting
property.int
getVisibleRowCount()
Returns the value of thevisibleRowCount
property.Point
indexToLocation(int index)
Returns the origin of the specified item in the list's coordinate system.boolean
isSelectedIndex(int index)
Returnstrue
if the specified index is selected, elsefalse
.boolean
isSelectionEmpty()
Returnstrue
if nothing is selected, elsefalse
.int
locationToIndex(Point location)
Returns the cell index closest to the given location in the list's coordinate system.protected String
paramString()
Returns aString
representation of thisJList
.void
removeListSelectionListener(ListSelectionListener listener)
Removes a selection listener from the list.void
removeSelectionInterval(int index0, int index1)
Sets the selection to be the set difference of the specified interval and the current selection.void
setCellRenderer(ListCellRenderer<? super E> cellRenderer)
Sets the delegate that is used to paint each cell in the list.void
setDragEnabled(boolean b)
Turns on or off automatic drag handling.void
setDropMode(DropMode dropMode)
Sets the drop mode for this component.void
setFixedCellHeight(int height)
Sets a fixed value to be used for the height of every cell in the list.void
setFixedCellWidth(int width)
Sets a fixed value to be used for the width of every cell in the list.void
setLayoutOrientation(int layoutOrientation)
Defines the way list cells are layed out.void
setListData(E[] listData)
Constructs a read-onlyListModel
from an array of items, and callssetModel
with this model.void
setListData(Vector<? extends E> listData)
Constructs a read-onlyListModel
from aVector
and callssetModel
with this model.void
setModel(ListModel<E> model)
Sets the model that represents the contents or "value" of the list, notifies property change listeners, and then clears the list's selection.void
setPrototypeCellValue(E prototypeCellValue)
Sets theprototypeCellValue
property, and then (if the new value isnon-null
), computes thefixedCellWidth
andfixedCellHeight
properties by requesting the cell renderer component for the given value (and index 0) from the cell renderer, and using that component's preferred size.void
setSelectedIndex(int index)
Selects a single cell.void
setSelectedIndices(int[] indices)
Changes the selection to be the set of indices specified by the given array.void
setSelectedValue(Object anObject, boolean shouldScroll)
Selects the specified object from the list.void
setSelectionBackground(Color selectionBackground)
Sets the color used to draw the background of selected items, which cell renderers can use fill selected cells.void
setSelectionForeground(Color selectionForeground)
Sets the color used to draw the foreground of selected items, which cell renderers can use to render text and graphics.void
setSelectionInterval(int anchor, int lead)
Selects the specified interval.void
setSelectionMode(int selectionMode)
Sets the selection mode for the list.void
setSelectionModel(ListSelectionModel selectionModel)
Sets theselectionModel
for the list to a non-null
ListSelectionModel
implementation.void
setUI(ListUI ui)
Sets theListUI
, the look and feel object that renders this component.void
setValueIsAdjusting(boolean b)
Sets the selection model'svalueIsAdjusting
property.void
setVisibleRowCount(int visibleRowCount)
Sets thevisibleRowCount
property, which has different meanings depending on the layout orientation: For aVERTICAL
layout orientation, this sets the preferred number of rows to display without requiring scrolling; for other orientations, it affects the wrapping of cells.void
updateUI()
Resets theListUI
property by setting it to the value provided by the current look and feel.-
Methods inherited from class javax.swing.JComponent
addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update
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Methods inherited from class java.awt.Container
add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree
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Methods inherited from class java.awt.Component
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle
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Field Detail
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VERTICAL
public static final int VERTICAL
Indicates a vertical layout of cells, in a single column; the default layout.- Since:
- 1.4
- See Also:
setLayoutOrientation(int)
, Constant Field Values
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VERTICAL_WRAP
public static final int VERTICAL_WRAP
Indicates a "newspaper style" layout with cells flowing vertically then horizontally.- Since:
- 1.4
- See Also:
setLayoutOrientation(int)
, Constant Field Values
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HORIZONTAL_WRAP
public static final int HORIZONTAL_WRAP
Indicates a "newspaper style" layout with cells flowing horizontally then vertically.- Since:
- 1.4
- See Also:
setLayoutOrientation(int)
, Constant Field Values
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Constructor Detail
-
JList
public JList(ListModel<E> dataModel)
Constructs aJList
that displays elements from the specified,non-null
, model. AllJList
constructors delegate to this one.This constructor registers the list with the
ToolTipManager
, allowing for tooltips to be provided by the cell renderers.- Parameters:
dataModel
- the model for the list- Throws:
IllegalArgumentException
- if the model isnull
-
JList
public JList(E[] listData)
Constructs aJList
that displays the elements in the specified array. This constructor creates a read-only model for the given array, and then delegates to the constructor that takes aListModel
.Attempts to pass a
null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the given array directly. Attempts to modify the array after constructing the list results in undefined behavior.- Parameters:
listData
- the array of Objects to be loaded into the data model,non-null
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JList
public JList(Vector<? extends E> listData)
Constructs aJList
that displays the elements in the specifiedVector
. This constructor creates a read-only model for the givenVector
, and then delegates to the constructor that takes aListModel
.Attempts to pass a
null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the givenVector
directly. Attempts to modify theVector
after constructing the list results in undefined behavior.- Parameters:
listData
- theVector
to be loaded into the data model,non-null
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JList
public JList()
Constructs aJList
with an empty, read-only, model.
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Method Detail
-
getUI
public ListUI getUI()
Returns theListUI
, the look and feel object that renders this component.- Returns:
- the
ListUI
object that renders this component
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setUI
public void setUI(ListUI ui)
Sets theListUI
, the look and feel object that renders this component.- Parameters:
ui
- theListUI
object- See Also:
UIDefaults.getUI(javax.swing.JComponent)
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updateUI
public void updateUI()
Resets theListUI
property by setting it to the value provided by the current look and feel. If the current cell renderer was installed by the developer (rather than the look and feel itself), this also causes the cell renderer and its children to be updated, by callingSwingUtilities.updateComponentTreeUI
on it.- Overrides:
updateUI
in classJComponent
- See Also:
UIManager.getUI(javax.swing.JComponent)
,SwingUtilities.updateComponentTreeUI(java.awt.Component)
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getUIClassID
public String getUIClassID()
Returns"ListUI"
, theUIDefaults
key used to look up the name of thejavax.swing.plaf.ListUI
class that defines the look and feel for this component.- Overrides:
getUIClassID
in classJComponent
- Returns:
- the string "ListUI"
- See Also:
JComponent.getUIClassID()
,UIDefaults.getUI(javax.swing.JComponent)
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getPrototypeCellValue
public E getPrototypeCellValue()
Returns the "prototypical" cell value -- a value used to calculate a fixed width and height for cells. This can benull
if there is no such value.- Returns:
- the value of the
prototypeCellValue
property - See Also:
setPrototypeCellValue(E)
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setPrototypeCellValue
public void setPrototypeCellValue(E prototypeCellValue)
Sets theprototypeCellValue
property, and then (if the new value isnon-null
), computes thefixedCellWidth
andfixedCellHeight
properties by requesting the cell renderer component for the given value (and index 0) from the cell renderer, and using that component's preferred size.This method is useful when the list is too long to allow the
ListUI
to compute the width/height of each cell, and there is a single cell value that is known to occupy as much space as any of the others, a so-called prototype.While all three of the
prototypeCellValue
,fixedCellHeight
, andfixedCellWidth
properties may be modified by this method,PropertyChangeEvent
notifications are only sent when theprototypeCellValue
property changes.To see an example which sets this property, see the class description above.
The default value of this property is
null
.This is a JavaBeans bound property.
- Parameters:
prototypeCellValue
- the value on which to basefixedCellWidth
andfixedCellHeight
- See Also:
getPrototypeCellValue()
,setFixedCellWidth(int)
,setFixedCellHeight(int)
,Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
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getFixedCellWidth
public int getFixedCellWidth()
Returns the value of thefixedCellWidth
property.- Returns:
- the fixed cell width
- See Also:
setFixedCellWidth(int)
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setFixedCellWidth
public void setFixedCellWidth(int width)
Sets a fixed value to be used for the width of every cell in the list. Ifwidth
is -1, cell widths are computed in theListUI
by applyinggetPreferredSize
to the cell renderer component for each list element.The default value of this property is
-1
.This is a JavaBeans bound property.
- Parameters:
width
- the width to be used for all cells in the list- See Also:
setPrototypeCellValue(E)
,setFixedCellWidth(int)
,Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
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getFixedCellHeight
public int getFixedCellHeight()
Returns the value of thefixedCellHeight
property.- Returns:
- the fixed cell height
- See Also:
setFixedCellHeight(int)
-
setFixedCellHeight
public void setFixedCellHeight(int height)
Sets a fixed value to be used for the height of every cell in the list. Ifheight
is -1, cell heights are computed in theListUI
by applyinggetPreferredSize
to the cell renderer component for each list element.The default value of this property is
-1
.This is a JavaBeans bound property.
- Parameters:
height
- the height to be used for for all cells in the list- See Also:
setPrototypeCellValue(E)
,setFixedCellWidth(int)
,Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
-
getCellRenderer
public ListCellRenderer<? super E> getCellRenderer()
Returns the object responsible for painting list items.- Returns:
- the value of the
cellRenderer
property - See Also:
setCellRenderer(javax.swing.ListCellRenderer<? super E>)
-
setCellRenderer
public void setCellRenderer(ListCellRenderer<? super E> cellRenderer)
Sets the delegate that is used to paint each cell in the list. The job of a cell renderer is discussed in detail in the class level documentation.If the
prototypeCellValue
property isnon-null
, setting the cell renderer also causes thefixedCellWidth
andfixedCellHeight
properties to be re-calculated. Only onePropertyChangeEvent
is generated however - for thecellRenderer
property.The default value of this property is provided by the
ListUI
delegate, i.e. by the look and feel implementation.This is a JavaBeans bound property.
- Parameters:
cellRenderer
- theListCellRenderer
that paints list cells- See Also:
getCellRenderer()
-
getSelectionForeground
public Color getSelectionForeground()
Returns the color used to draw the foreground of selected items.DefaultListCellRenderer
uses this color to draw the foreground of items in the selected state, as do the renderers installed by mostListUI
implementations.- Returns:
- the color to draw the foreground of selected items
- See Also:
setSelectionForeground(java.awt.Color)
,DefaultListCellRenderer
-
setSelectionForeground
public void setSelectionForeground(Color selectionForeground)
Sets the color used to draw the foreground of selected items, which cell renderers can use to render text and graphics.DefaultListCellRenderer
uses this color to draw the foreground of items in the selected state, as do the renderers installed by mostListUI
implementations.The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
- Parameters:
selectionForeground
- theColor
to use in the foreground for selected list items- See Also:
getSelectionForeground()
,setSelectionBackground(java.awt.Color)
,JComponent.setForeground(java.awt.Color)
,JComponent.setBackground(java.awt.Color)
,JComponent.setFont(java.awt.Font)
,DefaultListCellRenderer
-
getSelectionBackground
public Color getSelectionBackground()
Returns the color used to draw the background of selected items.DefaultListCellRenderer
uses this color to draw the background of items in the selected state, as do the renderers installed by mostListUI
implementations.- Returns:
- the color to draw the background of selected items
- See Also:
setSelectionBackground(java.awt.Color)
,DefaultListCellRenderer
-
setSelectionBackground
public void setSelectionBackground(Color selectionBackground)
Sets the color used to draw the background of selected items, which cell renderers can use fill selected cells.DefaultListCellRenderer
uses this color to fill the background of items in the selected state, as do the renderers installed by mostListUI
implementations.The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
- Parameters:
selectionBackground
- theColor
to use for the background of selected cells- See Also:
getSelectionBackground()
,setSelectionForeground(java.awt.Color)
,JComponent.setForeground(java.awt.Color)
,JComponent.setBackground(java.awt.Color)
,JComponent.setFont(java.awt.Font)
,DefaultListCellRenderer
-
getVisibleRowCount
public int getVisibleRowCount()
Returns the value of thevisibleRowCount
property. See the documentation forsetVisibleRowCount(int)
for details on how to interpret this value.- Returns:
- the value of the
visibleRowCount
property. - See Also:
setVisibleRowCount(int)
-
setVisibleRowCount
public void setVisibleRowCount(int visibleRowCount)
Sets thevisibleRowCount
property, which has different meanings depending on the layout orientation: For aVERTICAL
layout orientation, this sets the preferred number of rows to display without requiring scrolling; for other orientations, it affects the wrapping of cells.In
VERTICAL
orientation:
Setting this property affects the return value of thegetPreferredScrollableViewportSize()
method, which is used to calculate the preferred size of an enclosing viewport. See that method's documentation for more details.In
HORIZONTAL_WRAP
andVERTICAL_WRAP
orientations:
This affects how cells are wrapped. See the documentation ofsetLayoutOrientation(int)
for more details.The default value of this property is
8
.Calling this method with a negative value results in the property being set to
0
.This is a JavaBeans bound property.
- Parameters:
visibleRowCount
- an integer specifying the preferred number of rows to display without requiring scrolling- See Also:
getVisibleRowCount()
,getPreferredScrollableViewportSize()
,setLayoutOrientation(int)
,JComponent.getVisibleRect()
,JViewport
-
getLayoutOrientation
public int getLayoutOrientation()
Returns the layout orientation property for the list:VERTICAL
if the layout is a single column of cells,VERTICAL_WRAP
if the layout is "newspaper style" with the content flowing vertically then horizontally, orHORIZONTAL_WRAP
if the layout is "newspaper style" with the content flowing horizontally then vertically.- Returns:
- the value of the
layoutOrientation
property - Since:
- 1.4
- See Also:
setLayoutOrientation(int)
-
setLayoutOrientation
public void setLayoutOrientation(int layoutOrientation)
Defines the way list cells are layed out. Consider aJList
with five cells. Cells can be layed out in one of the following ways:VERTICAL: 0 1 2 3 4 HORIZONTAL_WRAP: 0 1 2 3 4 VERTICAL_WRAP: 0 3 1 4 2
A description of these layouts follows:
Value
Description
VERTICAL
Cells are layed out vertically in a single column. HORIZONTAL_WRAP
Cells are layed out horizontally, wrapping to a new row as necessary. If the visibleRowCount
property is less than or equal to zero, wrapping is determined by the width of the list; otherwise wrapping is done in such a way as to ensurevisibleRowCount
rows in the list.VERTICAL_WRAP
Cells are layed out vertically, wrapping to a new column as necessary. If the visibleRowCount
property is less than or equal to zero, wrapping is determined by the height of the list; otherwise wrapping is done atvisibleRowCount
rows.The default value of this property is
VERTICAL
.- Parameters:
layoutOrientation
- the new layout orientation, one of:VERTICAL
,HORIZONTAL_WRAP
orVERTICAL_WRAP
- Throws:
IllegalArgumentException
- iflayoutOrientation
isn't one of the allowable values- Since:
- 1.4
- See Also:
getLayoutOrientation()
,setVisibleRowCount(int)
,getScrollableTracksViewportHeight()
,getScrollableTracksViewportWidth()
-
getFirstVisibleIndex
public int getFirstVisibleIndex()
Returns the smallest list index that is currently visible. In a left-to-rightcomponentOrientation
, the first visible cell is found closest to the list's upper-left corner. In right-to-left orientation, it is found closest to the upper-right corner. If nothing is visible or the list is empty,-1
is returned. Note that the returned cell may only be partially visible.- Returns:
- the index of the first visible cell
- See Also:
getLastVisibleIndex()
,JComponent.getVisibleRect()
-
getLastVisibleIndex
public int getLastVisibleIndex()
Returns the largest list index that is currently visible. If nothing is visible or the list is empty,-1
is returned. Note that the returned cell may only be partially visible.- Returns:
- the index of the last visible cell
- See Also:
getFirstVisibleIndex()
,JComponent.getVisibleRect()
-
ensureIndexIsVisible
public void ensureIndexIsVisible(int index)
Scrolls the list within an enclosing viewport to make the specified cell completely visible. This callsscrollRectToVisible
with the bounds of the specified cell. For this method to work, theJList
must be within aJViewport
.If the given index is outside the list's range of cells, this method results in nothing.
- Parameters:
index
- the index of the cell to make visible- See Also:
JComponent.scrollRectToVisible(java.awt.Rectangle)
,JComponent.getVisibleRect()
-
setDragEnabled
public void setDragEnabled(boolean b)
Turns on or off automatic drag handling. In order to enable automatic drag handling, this property should be set totrue
, and the list'sTransferHandler
needs to benon-null
. The default value of thedragEnabled
property isfalse
.The job of honoring this property, and recognizing a user drag gesture, lies with the look and feel implementation, and in particular, the list's
ListUI
. When automatic drag handling is enabled, most look and feels (including those that subclassBasicLookAndFeel
) begin a drag and drop operation whenever the user presses the mouse button over an item and then moves the mouse a few pixels. Setting this property totrue
can therefore have a subtle effect on how selections behave.If a look and feel is used that ignores this property, you can still begin a drag and drop operation by calling
exportAsDrag
on the list'sTransferHandler
.- Parameters:
b
- whether or not to enable automatic drag handling- Throws:
HeadlessException
- ifb
istrue
andGraphicsEnvironment.isHeadless()
returnstrue
- Since:
- 1.4
- See Also:
GraphicsEnvironment.isHeadless()
,getDragEnabled()
,JComponent.setTransferHandler(javax.swing.TransferHandler)
,TransferHandler
-
getDragEnabled
public boolean getDragEnabled()
Returns whether or not automatic drag handling is enabled.- Returns:
- the value of the
dragEnabled
property - Since:
- 1.4
- See Also:
setDragEnabled(boolean)
-
setDropMode
public final void setDropMode(DropMode dropMode)
Sets the drop mode for this component. For backward compatibility, the default for this property isDropMode.USE_SELECTION
. Usage of one of the other modes is recommended, however, for an improved user experience.DropMode.ON
, for instance, offers similar behavior of showing items as selected, but does so without affecting the actual selection in the list.JList
supports the following drop modes:DropMode.USE_SELECTION
DropMode.ON
DropMode.INSERT
DropMode.ON_OR_INSERT
TransferHandler
that accepts drops.- Parameters:
dropMode
- the drop mode to use- Throws:
IllegalArgumentException
- if the drop mode is unsupported ornull
- Since:
- 1.6
- See Also:
getDropMode()
,getDropLocation()
,JComponent.setTransferHandler(javax.swing.TransferHandler)
,TransferHandler
-
getDropMode
public final DropMode getDropMode()
Returns the drop mode for this component.- Returns:
- the drop mode for this component
- Since:
- 1.6
- See Also:
setDropMode(javax.swing.DropMode)
-
getDropLocation
public final JList.DropLocation getDropLocation()
Returns the location that this component should visually indicate as the drop location during a DnD operation over the component, ornull
if no location is to currently be shown.This method is not meant for querying the drop location from a
TransferHandler
, as the drop location is only set after theTransferHandler
'scanImport
has returned and has allowed for the location to be shown.When this property changes, a property change event with name "dropLocation" is fired by the component.
By default, responsibility for listening for changes to this property and indicating the drop location visually lies with the list's
ListUI
, which may paint it directly and/or install a cell renderer to do so. Developers wishing to implement custom drop location painting and/or replace the default cell renderer, may need to honor this property.- Returns:
- the drop location
- Since:
- 1.6
- See Also:
setDropMode(javax.swing.DropMode)
,TransferHandler.canImport(TransferHandler.TransferSupport)
-
getNextMatch
public int getNextMatch(String prefix, int startIndex, Position.Bias bias)
Returns the next list element whosetoString
value starts with the given prefix.- Parameters:
prefix
- the string to test for a matchstartIndex
- the index for starting the searchbias
- the search direction, either Position.Bias.Forward or Position.Bias.Backward.- Returns:
- the index of the next list element that
starts with the prefix; otherwise
-1
- Throws:
IllegalArgumentException
- if prefix isnull
or startIndex is out of bounds- Since:
- 1.4
-
getToolTipText
public String getToolTipText(MouseEvent event)
Returns the tooltip text to be used for the given event. This overridesJComponent
'sgetToolTipText
to first check the cell renderer component for the cell over which the event occurred, returning its tooltip text, if any. This implementation allows you to specify tooltip text on the cell level, by usingsetToolTipText
on your cell renderer component.Note: ForJList
to properly display the tooltips of its renderers in this manner,JList
must be a registered component with theToolTipManager
. This registration is done automatically in the constructor. However, if at a later pointJList
is unregistered, by way of a call tosetToolTipText(null)
, tips from the renderers will no longer display.- Overrides:
getToolTipText
in classJComponent
- Parameters:
event
- theMouseEvent
to fetch the tooltip text for- See Also:
JComponent.setToolTipText(java.lang.String)
,JComponent.getToolTipText()
-
locationToIndex
public int locationToIndex(Point location)
Returns the cell index closest to the given location in the list's coordinate system. To determine if the cell actually contains the specified location, compare the point against the cell's bounds, as provided bygetCellBounds
. This method returns-1
if the model is emptyThis is a cover method that delegates to the method of the same name in the list's
ListUI
. It returns-1
if the list has noListUI
.- Parameters:
location
- the coordinates of the point- Returns:
- the cell index closest to the given location, or
-1
-
indexToLocation
public Point indexToLocation(int index)
Returns the origin of the specified item in the list's coordinate system. This method returnsnull
if the index isn't valid.This is a cover method that delegates to the method of the same name in the list's
ListUI
. It returnsnull
if the list has noListUI
.- Parameters:
index
- the cell index- Returns:
- the origin of the cell, or
null
-
getCellBounds
public Rectangle getCellBounds(int index0, int index1)
Returns the bounding rectangle, in the list's coordinate system, for the range of cells specified by the two indices. These indices can be supplied in any order.If the smaller index is outside the list's range of cells, this method returns
null
. If the smaller index is valid, but the larger index is outside the list's range, the bounds of just the first index is returned. Otherwise, the bounds of the valid range is returned.This is a cover method that delegates to the method of the same name in the list's
ListUI
. It returnsnull
if the list has noListUI
.- Parameters:
index0
- the first index in the rangeindex1
- the second index in the range- Returns:
- the bounding rectangle for the range of cells, or
null
-
getModel
public ListModel<E> getModel()
Returns the data model that holds the list of items displayed by theJList
component.- Returns:
- the
ListModel
that provides the displayed list of items - See Also:
setModel(javax.swing.ListModel<E>)
-
setModel
public void setModel(ListModel<E> model)
Sets the model that represents the contents or "value" of the list, notifies property change listeners, and then clears the list's selection.This is a JavaBeans bound property.
- Parameters:
model
- theListModel
that provides the list of items for display- Throws:
IllegalArgumentException
- ifmodel
isnull
- See Also:
getModel()
,clearSelection()
-
setListData
public void setListData(E[] listData)
Constructs a read-onlyListModel
from an array of items, and callssetModel
with this model.Attempts to pass a
null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the given array directly. Attempts to modify the array after invoking this method results in undefined behavior.- Parameters:
listData
- an array ofE
containing the items to display in the list- See Also:
setModel(javax.swing.ListModel<E>)
-
setListData
public void setListData(Vector<? extends E> listData)
Constructs a read-onlyListModel
from aVector
and callssetModel
with this model.Attempts to pass a
null
value to this method results in undefined behavior and, most likely, exceptions. The created model references the givenVector
directly. Attempts to modify theVector
after invoking this method results in undefined behavior.- Parameters:
listData
- aVector
containing the items to display in the list- See Also:
setModel(javax.swing.ListModel<E>)
-
createSelectionModel
protected ListSelectionModel createSelectionModel()
Returns an instance ofDefaultListSelectionModel
; called during construction to initialize the list's selection model property.- Returns:
- a
DefaultListSelecitonModel
, used to initialize the list's selection model property during construction - See Also:
setSelectionModel(javax.swing.ListSelectionModel)
,DefaultListSelectionModel
-
getSelectionModel
public ListSelectionModel getSelectionModel()
Returns the current selection model. The selection model maintains the selection state of the list. See the class level documentation for more details.- Returns:
- the
ListSelectionModel
that maintains the list's selections - See Also:
setSelectionModel(javax.swing.ListSelectionModel)
,ListSelectionModel
-
fireSelectionValueChanged
protected void fireSelectionValueChanged(int firstIndex, int lastIndex, boolean isAdjusting)
NotifiesListSelectionListener
s added directly to the list of selection changes made to the selection model.JList
listens for changes made to the selection in the selection model, and forwards notification to listeners added to the list directly, by calling this method.This method constructs a
ListSelectionEvent
with this list as the source, and the specified arguments, and sends it to the registeredListSelectionListeners
.- Parameters:
firstIndex
- the first index in the range,<= lastIndex
lastIndex
- the last index in the range,>= firstIndex
isAdjusting
- whether or not this is one in a series of multiple events, where changes are still being made- See Also:
addListSelectionListener(javax.swing.event.ListSelectionListener)
,removeListSelectionListener(javax.swing.event.ListSelectionListener)
,ListSelectionEvent
,EventListenerList
-
addListSelectionListener
public void addListSelectionListener(ListSelectionListener listener)
Adds a listener to the list, to be notified each time a change to the selection occurs; the preferred way of listening for selection state changes.JList
takes care of listening for selection state changes in the selection model, and notifies the given listener of each change.ListSelectionEvent
s sent to the listener have asource
property set to this list.- Parameters:
listener
- theListSelectionListener
to add- See Also:
getSelectionModel()
,getListSelectionListeners()
-
removeListSelectionListener
public void removeListSelectionListener(ListSelectionListener listener)
Removes a selection listener from the list.- Parameters:
listener
- theListSelectionListener
to remove- See Also:
addListSelectionListener(javax.swing.event.ListSelectionListener)
,getSelectionModel()
-
getListSelectionListeners
public ListSelectionListener[] getListSelectionListeners()
Returns an array of all theListSelectionListener
s added to thisJList
by way ofaddListSelectionListener
.- Returns:
- all of the
ListSelectionListener
s on this list, or an empty array if no listeners have been added - Since:
- 1.4
- See Also:
addListSelectionListener(javax.swing.event.ListSelectionListener)
-
setSelectionModel
public void setSelectionModel(ListSelectionModel selectionModel)
Sets theselectionModel
for the list to a non-null
ListSelectionModel
implementation. The selection model handles the task of making single selections, selections of contiguous ranges, and non-contiguous selections.This is a JavaBeans bound property.
- Parameters:
selectionModel
- theListSelectionModel
that implements the selections- Throws:
IllegalArgumentException
- ifselectionModel
isnull
- See Also:
getSelectionModel()
-
setSelectionMode
public void setSelectionMode(int selectionMode)
Sets the selection mode for the list. This is a cover method that sets the selection mode directly on the selection model.The following list describes the accepted selection modes:
ListSelectionModel.SINGLE_SELECTION
- Only one list index can be selected at a time. In this mode,setSelectionInterval
andaddSelectionInterval
are equivalent, both replacing the current selection with the index represented by the second argument (the "lead").ListSelectionModel.SINGLE_INTERVAL_SELECTION
- Only one contiguous interval can be selected at a time. In this mode,addSelectionInterval
behaves likesetSelectionInterval
(replacing the current selection}, unless the given interval is immediately adjacent to or overlaps the existing selection, and can be used to grow the selection.ListSelectionModel.MULTIPLE_INTERVAL_SELECTION
- In this mode, there's no restriction on what can be selected. This mode is the default.
- Parameters:
selectionMode
- the selection mode- Throws:
IllegalArgumentException
- if the selection mode isn't one of those allowed- See Also:
getSelectionMode()
-
getSelectionMode
public int getSelectionMode()
Returns the current selection mode for the list. This is a cover method that delegates to the method of the same name on the list's selection model.- Returns:
- the current selection mode
- See Also:
setSelectionMode(int)
-
getAnchorSelectionIndex
public int getAnchorSelectionIndex()
Returns the anchor selection index. This is a cover method that delegates to the method of the same name on the list's selection model.- Returns:
- the anchor selection index
- See Also:
ListSelectionModel.getAnchorSelectionIndex()
-
getLeadSelectionIndex
public int getLeadSelectionIndex()
Returns the lead selection index. This is a cover method that delegates to the method of the same name on the list's selection model.- Returns:
- the lead selection index
- See Also:
ListSelectionModel.getLeadSelectionIndex()
-
getMinSelectionIndex
public int getMinSelectionIndex()
Returns the smallest selected cell index, or-1
if the selection is empty. This is a cover method that delegates to the method of the same name on the list's selection model.- Returns:
- the smallest selected cell index, or
-1
- See Also:
ListSelectionModel.getMinSelectionIndex()
-
getMaxSelectionIndex
public int getMaxSelectionIndex()
Returns the largest selected cell index, or-1
if the selection is empty. This is a cover method that delegates to the method of the same name on the list's selection model.- Returns:
- the largest selected cell index
- See Also:
ListSelectionModel.getMaxSelectionIndex()
-
isSelectedIndex
public boolean isSelectedIndex(int index)
Returnstrue
if the specified index is selected, elsefalse
. This is a cover method that delegates to the method of the same name on the list's selection model.- Parameters:
index
- index to be queried for selection state- Returns:
true
if the specified index is selected, elsefalse
- See Also:
ListSelectionModel.isSelectedIndex(int)
,setSelectedIndex(int)
-
isSelectionEmpty
public boolean isSelectionEmpty()
Returnstrue
if nothing is selected, elsefalse
. This is a cover method that delegates to the method of the same name on the list's selection model.- Returns:
true
if nothing is selected, elsefalse
- See Also:
ListSelectionModel.isSelectionEmpty()
,clearSelection()
-
clearSelection
public void clearSelection()
Clears the selection; after calling this method,isSelectionEmpty
will returntrue
. This is a cover method that delegates to the method of the same name on the list's selection model.
-
setSelectionInterval
public void setSelectionInterval(int anchor, int lead)
Selects the specified interval. Bothanchor
andlead
indices are included.anchor
doesn't have to be less than or equal tolead
. This is a cover method that delegates to the method of the same name on the list's selection model.Refer to the documentation of the selection model class being used for details on how values less than
0
are handled.- Parameters:
anchor
- the first index to selectlead
- the last index to select- See Also:
ListSelectionModel.setSelectionInterval(int, int)
,DefaultListSelectionModel.setSelectionInterval(int, int)
,createSelectionModel()
,addSelectionInterval(int, int)
,removeSelectionInterval(int, int)
-
addSelectionInterval
public void addSelectionInterval(int anchor, int lead)
Sets the selection to be the union of the specified interval with current selection. Both theanchor
andlead
indices are included.anchor
doesn't have to be less than or equal tolead
. This is a cover method that delegates to the method of the same name on the list's selection model.Refer to the documentation of the selection model class being used for details on how values less than
0
are handled.- Parameters:
anchor
- the first index to add to the selectionlead
- the last index to add to the selection- See Also:
ListSelectionModel.addSelectionInterval(int, int)
,DefaultListSelectionModel.addSelectionInterval(int, int)
,createSelectionModel()
,setSelectionInterval(int, int)
,removeSelectionInterval(int, int)
-
removeSelectionInterval
public void removeSelectionInterval(int index0, int index1)
Sets the selection to be the set difference of the specified interval and the current selection. Both theindex0
andindex1
indices are removed.index0
doesn't have to be less than or equal toindex1
. This is a cover method that delegates to the method of the same name on the list's selection model.Refer to the documentation of the selection model class being used for details on how values less than
0
are handled.- Parameters:
index0
- the first index to remove from the selectionindex1
- the last index to remove from the selection- See Also:
ListSelectionModel.removeSelectionInterval(int, int)
,DefaultListSelectionModel.removeSelectionInterval(int, int)
,createSelectionModel()
,setSelectionInterval(int, int)
,addSelectionInterval(int, int)
-
setValueIsAdjusting
public void setValueIsAdjusting(boolean b)
Sets the selection model'svalueIsAdjusting
property. Whentrue
, upcoming changes to selection should be considered part of a single change. This property is used internally and developers typically need not call this method. For example, when the model is being updated in response to a user drag, the value of the property is set totrue
when the drag is initiated and set tofalse
when the drag is finished. This allows listeners to update only when a change has been finalized, rather than handling all of the intermediate values.You may want to use this directly if making a series of changes that should be considered part of a single change.
This is a cover method that delegates to the method of the same name on the list's selection model. See the documentation for
ListSelectionModel.setValueIsAdjusting(boolean)
for more details.- Parameters:
b
- the new value for the property- See Also:
ListSelectionModel.setValueIsAdjusting(boolean)
,ListSelectionEvent.getValueIsAdjusting()
,getValueIsAdjusting()
-
getValueIsAdjusting
public boolean getValueIsAdjusting()
Returns the value of the selection model'sisAdjusting
property.This is a cover method that delegates to the method of the same name on the list's selection model.
- Returns:
- the value of the selection model's
isAdjusting
property. - See Also:
setValueIsAdjusting(boolean)
,ListSelectionModel.getValueIsAdjusting()
-
getSelectedIndices
public int[] getSelectedIndices()
Returns an array of all of the selected indices, in increasing order.- Returns:
- all of the selected indices, in increasing order, or an empty array if nothing is selected
- See Also:
removeSelectionInterval(int, int)
,addListSelectionListener(javax.swing.event.ListSelectionListener)
-
setSelectedIndex
public void setSelectedIndex(int index)
Selects a single cell. Does nothing if the given index is greater than or equal to the model size. This is a convenience method that usessetSelectionInterval
on the selection model. Refer to the documentation for the selection model class being used for details on how values less than0
are handled.- Parameters:
index
- the index of the cell to select- See Also:
ListSelectionModel.setSelectionInterval(int, int)
,isSelectedIndex(int)
,addListSelectionListener(javax.swing.event.ListSelectionListener)
-
setSelectedIndices
public void setSelectedIndices(int[] indices)
Changes the selection to be the set of indices specified by the given array. Indices greater than or equal to the model size are ignored. This is a convenience method that clears the selection and then usesaddSelectionInterval
on the selection model to add the indices. Refer to the documentation of the selection model class being used for details on how values less than0
are handled.- Parameters:
indices
- an array of the indices of the cells to select,non-null
- Throws:
NullPointerException
- if the given array isnull
- See Also:
ListSelectionModel.addSelectionInterval(int, int)
,isSelectedIndex(int)
,addListSelectionListener(javax.swing.event.ListSelectionListener)
-
getSelectedValues
@Deprecated public Object[] getSelectedValues()
Deprecated. As of JDK 1.7, replaced bygetSelectedValuesList()
Returns an array of all the selected values, in increasing order based on their indices in the list.- Returns:
- the selected values, or an empty array if nothing is selected
- See Also:
isSelectedIndex(int)
,getModel()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
-
getSelectedValuesList
public List<E> getSelectedValuesList()
Returns a list of all the selected items, in increasing order based on their indices in the list.- Returns:
- the selected items, or an empty list if nothing is selected
- Since:
- 1.7
- See Also:
isSelectedIndex(int)
,getModel()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
-
getSelectedIndex
public int getSelectedIndex()
Returns the smallest selected cell index; the selection when only a single item is selected in the list. When multiple items are selected, it is simply the smallest selected index. Returns-1
if there is no selection.This method is a cover that delegates to
getMinSelectionIndex
.- Returns:
- the smallest selected cell index
- See Also:
getMinSelectionIndex()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
-
getSelectedValue
public E getSelectedValue()
Returns the value for the smallest selected cell index; the selected value when only a single item is selected in the list. When multiple items are selected, it is simply the value for the smallest selected index. Returnsnull
if there is no selection.This is a convenience method that simply returns the model value for
getMinSelectionIndex
.- Returns:
- the first selected value
- See Also:
getMinSelectionIndex()
,getModel()
,addListSelectionListener(javax.swing.event.ListSelectionListener)
-
setSelectedValue
public void setSelectedValue(Object anObject, boolean shouldScroll)
Selects the specified object from the list.- Parameters:
anObject
- the object to selectshouldScroll
-true
if the list should scroll to display the selected object, if one exists; otherwisefalse
-
getPreferredScrollableViewportSize
public Dimension getPreferredScrollableViewportSize()
Computes the size of viewport needed to displayvisibleRowCount
rows. The value returned by this method depends on the layout orientation:VERTICAL
:
This is trivial if bothfixedCellWidth
andfixedCellHeight
have been set (either explicitly or by specifying a prototype cell value). The width is simply thefixedCellWidth
plus the list's horizontal insets. The height is thefixedCellHeight
multiplied by thevisibleRowCount
, plus the list's vertical insets.If either
fixedCellWidth
orfixedCellHeight
haven't been specified, heuristics are used. If the model is empty, the width is thefixedCellWidth
, if greater than0
, or a hard-coded value of256
. The height is thefixedCellHeight
multiplied byvisibleRowCount
, iffixedCellHeight
is greater than0
, otherwise it is a hard-coded value of16
multiplied byvisibleRowCount
.If the model isn't empty, the width is the preferred size's width, typically the width of the widest list element. The height is the
fixedCellHeight
multiplied by thevisibleRowCount
, plus the list's vertical insets.VERTICAL_WRAP
orHORIZONTAL_WRAP
:
This method simply returns the value fromgetPreferredSize
. The list'sListUI
is expected to overridegetPreferredSize
to return an appropriate value.- Specified by:
getPreferredScrollableViewportSize
in interfaceScrollable
- Returns:
- a dimension containing the size of the viewport needed
to display
visibleRowCount
rows - See Also:
getPreferredScrollableViewportSize()
,setPrototypeCellValue(E)
-
getScrollableUnitIncrement
public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous row (for vertical scrolling) or column (for horizontal scrolling).For horizontal scrolling, if the layout orientation is
VERTICAL
, then the list's font size is returned (or1
if the font isnull
).- Specified by:
getScrollableUnitIncrement
in interfaceScrollable
- Parameters:
visibleRect
- the view area visible within the viewportorientation
-SwingConstants.HORIZONTAL
orSwingConstants.VERTICAL
direction
- less or equal to zero to scroll up/back, greater than zero for down/forward- Returns:
- the "unit" increment for scrolling in the specified direction; always positive
- Throws:
IllegalArgumentException
- ifvisibleRect
isnull
, ororientation
isn't one ofSwingConstants.VERTICAL
orSwingConstants.HORIZONTAL
- See Also:
getScrollableBlockIncrement(java.awt.Rectangle, int, int)
,Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)
-
getScrollableBlockIncrement
public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous block.For vertical scrolling, the following rules are used:
- if scrolling down, returns the distance to scroll so that the last visible element becomes the first completely visible element
- if scrolling up, returns the distance to scroll so that the first visible element becomes the last completely visible element
- returns
visibleRect.height
if the list is empty
For horizontal scrolling, when the layout orientation is either
VERTICAL_WRAP
orHORIZONTAL_WRAP
:- if scrolling right, returns the distance to scroll so that the last visible element becomes the first completely visible element
- if scrolling left, returns the distance to scroll so that the first visible element becomes the last completely visible element
- returns
visibleRect.width
if the list is empty
For horizontal scrolling and
VERTICAL
orientation, returnsvisibleRect.width
.Note that the value of
visibleRect
must be the equal tothis.getVisibleRect()
.- Specified by:
getScrollableBlockIncrement
in interfaceScrollable
- Parameters:
visibleRect
- the view area visible within the viewportorientation
-SwingConstants.HORIZONTAL
orSwingConstants.VERTICAL
direction
- less or equal to zero to scroll up/back, greater than zero for down/forward- Returns:
- the "block" increment for scrolling in the specified direction; always positive
- Throws:
IllegalArgumentException
- ifvisibleRect
isnull
, ororientation
isn't one ofSwingConstants.VERTICAL
orSwingConstants.HORIZONTAL
- See Also:
getScrollableUnitIncrement(java.awt.Rectangle, int, int)
,Scrollable.getScrollableBlockIncrement(java.awt.Rectangle, int, int)
-
getScrollableTracksViewportWidth
public boolean getScrollableTracksViewportWidth()
Returnstrue
if thisJList
is displayed in aJViewport
and the viewport is wider than the list's preferred width, or if the layout orientation isHORIZONTAL_WRAP
andvisibleRowCount <= 0
; otherwise returnsfalse
.If
false
, then don't track the viewport's width. This allows horizontal scrolling if theJViewport
is itself embedded in aJScrollPane
.- Specified by:
getScrollableTracksViewportWidth
in interfaceScrollable
- Returns:
- whether or not an enclosing viewport should force the list's width to match its own
- See Also:
Scrollable.getScrollableTracksViewportWidth()
-
getScrollableTracksViewportHeight
public boolean getScrollableTracksViewportHeight()
Returnstrue
if thisJList
is displayed in aJViewport
and the viewport is taller than the list's preferred height, or if the layout orientation isVERTICAL_WRAP
andvisibleRowCount <= 0
; otherwise returnsfalse
.If
false
, then don't track the viewport's height. This allows vertical scrolling if theJViewport
is itself embedded in aJScrollPane
.- Specified by:
getScrollableTracksViewportHeight
in interfaceScrollable
- Returns:
- whether or not an enclosing viewport should force the list's height to match its own
- See Also:
Scrollable.getScrollableTracksViewportHeight()
-
paramString
protected String paramString()
Returns aString
representation of thisJList
. This method is intended to be used only for debugging purposes, and the content and format of the returnedString
may vary between implementations. The returnedString
may be empty, but may not benull
.- Overrides:
paramString
in classJComponent
- Returns:
- a
String
representation of thisJList
.
-
getAccessibleContext
public AccessibleContext getAccessibleContext()
Gets theAccessibleContext
associated with thisJList
. ForJList
, theAccessibleContext
takes the form of anAccessibleJList
.A new
AccessibleJList
instance is created if necessary.- Specified by:
getAccessibleContext
in interfaceAccessible
- Overrides:
getAccessibleContext
in classJComponent
- Returns:
- an
AccessibleJList
that serves as theAccessibleContext
of thisJList
-
-
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