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java.lang.Object
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+--java.awt.Component
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+--java.awt.Container
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+--javax.swing.JComponent
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+--javax.swing.JList
A component that allows the user to select one or more objects from a
list. A separate model, ListModel, represents the contents
of the list. It's easy to display an array or vector of objects, using
a JList constructor that builds a ListModel
instance for you:
// Create a JList that displays the strings in data[]
String[] data = {"one", "two", "three", "four"};
JList dataList = new JList(data);
// The value of the JList model property is an object that provides
// a read-only view of the data. It was constructed automatically.
for(int i = 0; i < dataList.getModel().getSize(); i++) {
System.out.println(dataList.getModel().getElementAt(i));
}
// Create a JList that displays the superclass of JList.class.
// We store the superclasses in a java.util.Vector.
Vector superClasses = new Vector();
Class rootClass = javax.swing.JList.class;
for(Class cls = rootClass; cls != null; cls = cls.getSuperclass()) {
superClasses.addElement(cls);
}
JList classList = new JList(superClasses);
JList doesn't support scrolling directly.
To create a scrolling
list you make the JList the viewport view of a
JScrollPane. For example:
JScrollPane scrollPane = new JScrollPane(dataList); // Or in two steps: JScrollPane scrollPane = new JScrollPane(); scrollPane.getViewport().setView(dataList);
By default the JList selection model allows any
combination of items to be selected at a time, using the constant
MULTIPLE_INTERVAL_SELECTION.
The selection state is actually managed
by a separate delegate object, an instance of
ListSelectionModel.
However JList provides convenient properties for
managing the selection.
String[] data = {"one", "two", "three", "four"};
JList dataList = new JList(data);
dataList.setSelectedIndex(1); // select "two"
dataList.getSelectedValue(); // returns "two"
The contents of a JList can be dynamic,
in other words, the list elements can
change value and the size of the list can change after the
JList has
been created. The JList observes changes in its model with a
swing.event.ListDataListener implementation. A correct
implementation of ListModel notifies
it's listeners each time a change occurs. The changes are
characterized by a swing.event.ListDataEvent, which identifies
the range of list indices that have been modified, added, or removed.
Simple dynamic-content JList applications can use the
DefaultListModel class to store list elements. This class
implements the ListModel interface and provides the
java.util.Vector API as well. Applications that need to
provide custom ListModel implementations can subclass
AbstractListModel, which provides basic
ListDataListener support. For example:
// This list model has about 2^16 elements. Enjoy scrolling.
ListModel bigData = new AbstractListModel() {
public int getSize() { return Short.MAX_VALUE; }
public Object getElementAt(int index) { return "Index " + index; }
};
JList bigDataList = new JList(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 uses a java.awt.Component, provided by
a delegate called the
cellRendererer, to paint the visible cells in the list.
The cell renderer component is used like a "rubber stamp" to paint
each visible row. Each time the JList needs to paint a cell
it asks the cell renderer for the component, moves it into place
using setBounds() and then draws it by calling its paint method.
The default cell renderer uses a JLabel component to render
the string value of each component. You can substitute your
own cell renderer, using code like this:
// Display an icon and a string for each object in the list.
class MyCellRenderer extends JLabel implements ListCellRenderer {
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,
Object value, // value to display
int index, // cell index
boolean isSelected, // is the cell selected
boolean cellHasFocus) // the list and the cell have the 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());
return this;
}
}
String[] data = {"one", "two", "three", "four"};
JList dataList = new JList(data);
dataList.setCellRenderer(new MyCellRenderer());
JList doesn't provide any special support for handling double or
triple (or N) mouse clicks however it's easy to handle them using
a MouseListener. Use the JList method
locationToIndex() to
determine what cell was clicked. For example:
final JList list = new JList(dataModel);
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);
Note that in this example the dataList is final
because it's referred to by the anonymous MouseListener class.
For the keyboard keys used by this component in the standard look and feel (L&F) renditions, see the JList key assignments.
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. A future release of Swing will provide support for long term persistence.
See How to Use Lists in The Java Tutorial for further documentation. Also see the article Advanced JList Programming in The Swing Connection.
ListModel,
AbstractListModel,
DefaultListModel,
ListSelectionModel,
DefaultListSelectionModel,
ListCellRenderer, Serialized Form| Inner Class Summary | |
protected class |
JList.AccessibleJList
This class implements accessibility support for the JList class. |
| Inner classes inherited from class javax.swing.JComponent |
JComponent.AccessibleJComponent |
| Inner classes inherited from class java.awt.Container |
Container.AccessibleAWTContainer |
| Inner classes inherited from class java.awt.Component |
Component.AccessibleAWTComponent |
| 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 |
| Fields inherited from class java.awt.Component |
BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT |
| Fields inherited from interface java.awt.image.ImageObserver |
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH |
| Constructor Summary | |
JList()
Constructs a JList with an empty model. |
|
JList(ListModel dataModel)
Constructs a JList that displays the elements in the
specified, non-null model. |
|
JList(Object[] listData)
Constructs a JList that displays the elements in the specified
array. |
|
JList(Vector listData)
Constructs a JList that displays the elements in the specified
Vector. |
|
| Method Summary | |
void |
addListSelectionListener(ListSelectionListener listener)
Adds a listener to the list that's notified each time a change to the selection occurs. |
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 return true. |
protected ListSelectionModel |
createSelectionModel()
Returns an instance of DefaultListSelectionModel. |
void |
ensureIndexIsVisible(int index)
Scrolls the viewport to make the specified cell completely visible. |
protected void |
fireSelectionValueChanged(int firstIndex,
int lastIndex,
boolean isAdjusting)
Notifies JList ListSelectionListeners that
the selection model has changed. |
AccessibleContext |
getAccessibleContext()
Gets the AccessibleContext associated with this JList. |
int |
getAnchorSelectionIndex()
Returns the first index argument from the most recent addSelectionModel or setSelectionInterval call. |
Rectangle |
getCellBounds(int index0,
int index1)
Returns the bounds of the specified range of items in JList
coordinates. |
ListCellRenderer |
getCellRenderer()
Returns the object that renders the list items. |
int |
getFirstVisibleIndex()
Returns the index of the cell in the upper left corner of the JList
or -1 if nothing is visible or the list is empty. |
int |
getFixedCellHeight()
Returns the fixed cell height value -- the value specified by setting the fixedCellHeight property,
rather than that calculated from the list elements. |
int |
getFixedCellWidth()
Returns the fixed cell width value -- the value specified by setting the fixedCellWidth property, rather than that calculated
from the list elements. |
int |
getLastVisibleIndex()
Returns the index of the cell in the lower right corner of the JList
or -1 if nothing is visible or the list is empty. |
int |
getLeadSelectionIndex()
Returns the second index argument from the most recent addSelectionInterval or setSelectionInterval
call. |
int |
getMaxSelectionIndex()
Returns the largest selected cell index. |
int |
getMinSelectionIndex()
Returns the smallest selected cell index. |
ListModel |
getModel()
Returns the data model that holds the list of items displayed by the JList component. |
Dimension |
getPreferredScrollableViewportSize()
Computes the size of the viewport needed to display visibleRowCount
rows. |
Object |
getPrototypeCellValue()
Returns the cell width of the "prototypical cell" -- a cell used for the calculation of cell widths, because it has the same value as all other list items. |
int |
getScrollableBlockIncrement(Rectangle visibleRect,
int orientation,
int direction)
Returns the block increment amount. |
boolean |
getScrollableTracksViewportHeight()
Returns true if this JList is displayed in a
JViewport and the viewport is taller than
JList's preferred height; otherwise returns false. |
boolean |
getScrollableTracksViewportWidth()
Returns true if this JList is displayed in a
JViewport and the viewport is wider than
JList's preferred width; otherwise returns false. |
int |
getScrollableUnitIncrement(Rectangle visibleRect,
int orientation,
int direction)
Returns the distance to scroll to expose the next or previous row (for vertical scrolling) or character (for horizontal scrolling). |
int |
getSelectedIndex()
Returns the first selected index; returns -1 if there is no selected item. |
int[] |
getSelectedIndices()
Returns an array of all of the selected indices in increasing order. |
Object |
getSelectedValue()
Returns the first selected value, or null if the
selection is empty. |
Object[] |
getSelectedValues()
Returns an array of the values for the selected cells. |
Color |
getSelectionBackground()
Returns the background color for selected cells. |
Color |
getSelectionForeground()
Returns the selection foreground color. |
int |
getSelectionMode()
Returns whether single-item or multiple-item selections are allowed. |
ListSelectionModel |
getSelectionModel()
Returns the value of the current selection model. |
ListUI |
getUI()
Returns the look and feel (L&F) object that renders this component. |
String |
getUIClassID()
Returns the suffix used to construct the name of the look and feel (L&F) class used to render this component. |
boolean |
getValueIsAdjusting()
Returns the value of the data model's isAdjusting property. |
int |
getVisibleRowCount()
Returns the preferred number of visible rows. |
Point |
indexToLocation(int index)
Returns the origin of the specified item in JList
coordinates. |
boolean |
isSelectedIndex(int index)
Returns true if the specified index is selected. |
boolean |
isSelectionEmpty()
Returns true if nothing is selected. |
int |
locationToIndex(Point location)
Converts a point in JList coordinates to the index
of the cell at that location. |
protected String |
paramString()
Returns a string representation of this JList. |
void |
removeListSelectionListener(ListSelectionListener listener)
Removes a listener from the list that's notified each time a change to the selection occurs. |
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 cellRenderer)
Sets the delegate that's used to paint each cell in the list. |
void |
setFixedCellHeight(int height)
Sets the height of every cell in the list. |
void |
setFixedCellWidth(int width)
Sets the width of every cell in the list. |
void |
setListData(Object[] listData)
Constructs a ListModel from an array of objects and then
applies setModel to it. |
void |
setListData(Vector listData)
Constructs a ListModel from a Vector and then
applies setModel to it. |
void |
setModel(ListModel model)
Sets the model that represents the contents or "value" of the list and clears the list selection after notifying PropertyChangeListeners. |
void |
setPrototypeCellValue(Object prototypeCellValue)
Computes the fixedCellWidth and
fixedCellHeight properties
by configuring the cellRenderer to index equals
zero for the specified value and then computing the renderer
component's preferred size. |
void |
setSelectedIndex(int index)
Selects a single cell. |
void |
setSelectedIndices(int[] indices)
Selects a set of cells. |
void |
setSelectedValue(Object anObject,
boolean shouldScroll)
Selects the specified object from the list. |
void |
setSelectionBackground(Color selectionBackground)
Sets the background color for selected cells. |
void |
setSelectionForeground(Color selectionForeground)
Sets the foreground color for selected cells. |
void |
setSelectionInterval(int anchor,
int lead)
Selects the specified interval. |
void |
setSelectionMode(int selectionMode)
Determines whether single-item or multiple-item selections are allowed. |
void |
setSelectionModel(ListSelectionModel selectionModel)
Sets the selectionModel for the list to a
non-null ListSelectionModel
implementation. |
void |
setUI(ListUI ui)
Sets the look and feel (L&F) object that renders this component. |
void |
setValueIsAdjusting(boolean b)
Sets the data model's isAdjusting property to true,
so that a single event will be generated when all of the selection
events have finished (for example, when the mouse is being
dragged over the list in selection mode). |
void |
setVisibleRowCount(int visibleRowCount)
Sets the preferred number of rows in the list that can be displayed without a scollbar, as determined by the nearest JViewport ancestor, if any. |
void |
updateUI()
Sets the UI property with the "ListUI" from the current default UIFactory. |
| Methods inherited from class java.awt.Container |
add, add, add, add, add, addContainerListener, addImpl, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getLayout, insets, invalidate, isAncestorOf, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setLayout, validate, validateTree |
| Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait |
| Constructor Detail |
public JList(ListModel dataModel)
JList that displays the elements in the
specified, non-null model. All JList constructors
delegate to this one.dataModel - the data model for this listIllegalArgumentException - if dataModel
is nullpublic JList(Object[] listData)
JList that displays the elements in the specified
array. This constructor just delegates to the ListModel
constructor.listData - the array of Objects to be loaded into the data modelpublic JList(Vector listData)
JList that displays the elements in the specified
Vector. This constructor just delegates to the
ListModel constructor.listData - the Vector to be loaded into the data modelpublic JList()
JList with an empty model.| Method Detail |
public ListUI getUI()
public void setUI(ListUI ui)
ui - the ListUI L&F objectUIDefaults.getUI(javax.swing.JComponent)public void updateUI()
JList constructor
and to update the list's look and feel at runtime.updateUI in class JComponentUIManager.getUI(javax.swing.JComponent)public String getUIClassID()
getUIClassID in class JComponentJComponent.getUIClassID(),
UIDefaults.getUI(javax.swing.JComponent)public Object getPrototypeCellValue()
prototypeCellValue propertysetPrototypeCellValue(java.lang.Object)public void setPrototypeCellValue(Object prototypeCellValue)
fixedCellWidth and
fixedCellHeight properties
by configuring the cellRenderer to index equals
zero for the specified value and then computing the renderer
component's preferred size. These properties are useful when the
list is too long to allow JList 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.
Note that we do set the fixedCellWidth and
fixedCellHeight properties here but only a
prototypeCellValue PropertyChangeEvent is fired.
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.
prototypeCellValue - the value on which to base
fixedCellWidth and
fixedCellHeightgetPrototypeCellValue(),
setFixedCellWidth(int),
setFixedCellHeight(int),
JComponent.addPropertyChangeListener(java.beans.PropertyChangeListener)public int getFixedCellWidth()
fixedCellWidth property, rather than that calculated
from the list elements.setFixedCellWidth(int)public void setFixedCellWidth(int width)
width is -1,
cell widths are computed by applying getPreferredSize
to the cellRenderer component for each list element.
The default value of this property is -1.
This is a JavaBeans bound property.
width - the width, in pixels, for all cells in this listgetPrototypeCellValue(),
setFixedCellWidth(int),
JComponent.addPropertyChangeListener(java.beans.PropertyChangeListener)public int getFixedCellHeight()
fixedCellHeight property,
rather than that calculated from the list elements.setFixedCellHeight(int)public void setFixedCellHeight(int height)
height
is -1, cell
heights are computed by applying getPreferredSize
to the cellRenderer component for each list element.
The default value of this property is -1.
This is a JavaBeans bound property.
height - an integer giving the height, in pixels, for all cells
in this listgetPrototypeCellValue(),
setFixedCellWidth(int),
JComponent.addPropertyChangeListener(java.beans.PropertyChangeListener)public ListCellRenderer getCellRenderer()
ListCellRenderersetCellRenderer(javax.swing.ListCellRenderer)public void setCellRenderer(ListCellRenderer cellRenderer)
prototypeCellValue was set then the
fixedCellWidth and fixedCellHeight
properties are set as well. Only one PropertyChangeEvent
is generated however - for the cellRenderer property.
The default value of this property is provided by the ListUI delegate, i.e. by the look and feel implementation.
To see an example which sets the cell renderer, see the class description above.
This is a JavaBeans bound property.
cellRenderer - the ListCellRenderer
that paints list cellsgetCellRenderer()public Color getSelectionForeground()
Color object for the foreground propertysetSelectionForeground(java.awt.Color),
setSelectionBackground(java.awt.Color)public void setSelectionForeground(Color selectionForeground)
The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
selectionForeground - the Color to use in the foreground
for selected list itemsgetSelectionForeground(),
setSelectionBackground(java.awt.Color),
JComponent.setForeground(java.awt.Color),
JComponent.setBackground(java.awt.Color),
JComponent.setFont(java.awt.Font)public Color getSelectionBackground()
Color used for the background of
selected list itemssetSelectionBackground(java.awt.Color),
setSelectionForeground(java.awt.Color)public void setSelectionBackground(Color selectionBackground)
The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
selectionBackground - the Color to use for the
background of selected cellsgetSelectionBackground(),
setSelectionForeground(java.awt.Color),
JComponent.setForeground(java.awt.Color),
JComponent.setBackground(java.awt.Color),
JComponent.setFont(java.awt.Font)public int getVisibleRowCount()
setVisibleRowCount(int)public void setVisibleRowCount(int visibleRowCount)
JViewport ancestor, if any.
The value of this property only affects the value of
the JList's preferredScrollableViewportSize.
The default value of this property is 8.
This is a JavaBeans bound property.
visibleRowCount - an integer specifying the preferred number of
visible rowsgetVisibleRowCount(),
JComponent.getVisibleRect(),
JViewportpublic int getFirstVisibleIndex()
JList
or -1 if nothing is visible or the list is empty. Note that this
cell may only be partially visible.getLastVisibleIndex(),
JComponent.getVisibleRect()public int getLastVisibleIndex()
JList
or -1 if nothing is visible or the list is empty. Note that this
cell may only be partially visible.getLastVisibleIndex(),
JComponent.getVisibleRect()public void ensureIndexIsVisible(int index)
JList must be
displayed within a JViewport.index - the index of the cell to make visibleJComponent.scrollRectToVisible(java.awt.Rectangle),
JComponent.getVisibleRect()public int locationToIndex(Point location)
JList coordinates to the index
of the cell at that location. Returns -1 if there's no
cell at the specified location.location - the coordinates of the cell, relative to
JListpublic Point indexToLocation(int index)
JList
coordinates. Returns null if index isn't valid.index - the index of the JList cell
public Rectangle getCellBounds(int index0,
int index1)
JList
coordinates. Returns null if index isn't valid.index0 - the index of the first JList cell in the rangeindex1 - the index of the last JList cell in the rangepublic ListModel getModel()
JList component.ListModel that provides the displayed
list of itemssetModel(javax.swing.ListModel)public void setModel(ListModel model)
PropertyChangeListeners.
This is a JavaBeans bound property.
model - the ListModel that provides the
list of items for displayIllegalArgumentException - if model is
nullgetModel()public void setListData(Object[] listData)
ListModel from an array of objects and then
applies setModel to it.listData - an array of Objects containing the items to display
in the listsetModel(javax.swing.ListModel)public void setListData(Vector listData)
ListModel from a Vector and then
applies setModel to it.listData - a Vector containing the items to
display in the listsetModel(javax.swing.ListModel)protected ListSelectionModel createSelectionModel()
DefaultListSelectionModel. This
method is used by the constructor to initialize the
selectionModel property.ListSelectionModel used by this
JList.setSelectionModel(javax.swing.ListSelectionModel),
DefaultListSelectionModelpublic ListSelectionModel getSelectionModel()
ListSelectionModel that implements
list selectionssetSelectionModel(javax.swing.ListSelectionModel),
ListSelectionModel
protected void fireSelectionValueChanged(int firstIndex,
int lastIndex,
boolean isAdjusting)
JList ListSelectionListeners that
the selection model has changed. It's used to forward
ListSelectionEvents from the selectionModel
to the ListSelectionListeners added directly to the
JList.firstIndex - the first selected indexlastIndex - the last selected indexisAdjusting - true if multiple changes are being madeaddListSelectionListener(javax.swing.event.ListSelectionListener),
removeListSelectionListener(javax.swing.event.ListSelectionListener),
EventListenerListpublic void addListSelectionListener(ListSelectionListener listener)
JList
will have their ListSelectionEvent.getSource() ==
this JList
(instead of the ListSelectionModel).listener - the ListSelectionListener to addgetSelectionModel()public void removeListSelectionListener(ListSelectionListener listener)
listener - the ListSelectionListener to removeaddListSelectionListener(javax.swing.event.ListSelectionListener),
getSelectionModel()public void setSelectionModel(ListSelectionModel selectionModel)
selectionModel 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.
selectionModel - the ListSelectionModel that
implements the selectionsIllegalArgumentException - if selectionModel
is nullgetSelectionModel()public void setSelectionMode(int selectionMode)
selectionMode values are allowed:
SINGLE_SELECTION
Only one list index can be selected at a time. In this
mode the setSelectionInterval and
addSelectionInterval
methods are equivalent, and only the second index
argument is used.
SINGLE_INTERVAL_SELECTION
One contiguous index interval can be selected at a time.
In this mode setSelectionInterval and
addSelectionInterval
are equivalent.
MULTIPLE_INTERVAL_SELECTION
In this mode, there's no restriction on what can be selected.
This is the default.
selectionMode - an integer specifying the type of selections
that are permissiblegetSelectionMode()public int getSelectionMode()
selectionMode propertysetSelectionMode(int)public int getAnchorSelectionIndex()
addSelectionModel or setSelectionInterval call.
This is a convenience method that just delegates to the
selectionModel.ListSelectionModel.getAnchorSelectionIndex(),
addSelectionInterval(int, int),
setSelectionInterval(int, int),
addListSelectionListener(javax.swing.event.ListSelectionListener)public int getLeadSelectionIndex()
addSelectionInterval or setSelectionInterval
call.
This is a convenience method that just delegates to the
selectionModel.ListSelectionModel.getLeadSelectionIndex(),
addSelectionInterval(int, int),
setSelectionInterval(int, int),
addListSelectionListener(javax.swing.event.ListSelectionListener)public int getMinSelectionIndex()
selectionModel.ListSelectionModel.getMinSelectionIndex(),
addListSelectionListener(javax.swing.event.ListSelectionListener)public int getMaxSelectionIndex()
selectionModel.ListSelectionModel.getMaxSelectionIndex(),
addListSelectionListener(javax.swing.event.ListSelectionListener)public boolean isSelectedIndex(int index)
selectionModel.index - index to be queried for selection stateListSelectionModel.isSelectedIndex(int),
setSelectedIndex(int),
addListSelectionListener(javax.swing.event.ListSelectionListener)public boolean isSelectionEmpty()
selectionModel.ListSelectionModel.isSelectionEmpty(),
clearSelection(),
addListSelectionListener(javax.swing.event.ListSelectionListener)public void clearSelection()
isSelectionEmpty will return true.
This is a convenience method that just delegates to the
selectionModel.ListSelectionModel.clearSelection(),
isSelectionEmpty(),
addListSelectionListener(javax.swing.event.ListSelectionListener)
public void setSelectionInterval(int anchor,
int lead)
selectionModel.anchor - the first index to selectlead - the last index to selectListSelectionModel.setSelectionInterval(int, int),
addSelectionInterval(int, int),
removeSelectionInterval(int, int),
addListSelectionListener(javax.swing.event.ListSelectionListener)
public void addSelectionInterval(int anchor,
int lead)
selectionModel.anchor - the first index to add to the selectionlead - the last index to add to the selectionListSelectionModel.addSelectionInterval(int, int),
setSelectionInterval(int, int),
removeSelectionInterval(int, int),
addListSelectionListener(javax.swing.event.ListSelectionListener)
public void removeSelectionInterval(int index0,
int index1)
selectionModel.anchor - the first index to remove from the selectionlead - the last index to remove from the selectionListSelectionModel.removeSelectionInterval(int, int),
setSelectionInterval(int, int),
addSelectionInterval(int, int),
addListSelectionListener(javax.swing.event.ListSelectionListener)public void setValueIsAdjusting(boolean b)
isAdjusting property to true,
so that a single event will be generated when all of the selection
events have finished (for example, when the mouse is being
dragged over the list in selection mode).b - the boolean value for the property valueListSelectionModel.setValueIsAdjusting(boolean)public boolean getValueIsAdjusting()
isAdjusting property.
This value is true if multiple changes are being made.ListSelectionModel.getValueIsAdjusting()public int[] getSelectedIndices()
removeSelectionInterval(int, int),
addListSelectionListener(javax.swing.event.ListSelectionListener)public void setSelectedIndex(int index)
index - the index of the one cell to selectListSelectionModel.setSelectionInterval(int, int),
isSelectedIndex(int),
addListSelectionListener(javax.swing.event.ListSelectionListener)public void setSelectedIndices(int[] indices)
indices - an array of the indices of the cells to selectListSelectionModel.addSelectionInterval(int, int),
isSelectedIndex(int),
addListSelectionListener(javax.swing.event.ListSelectionListener)public Object[] getSelectedValues()
isSelectedIndex(int),
getModel(),
addListSelectionListener(javax.swing.event.ListSelectionListener)public int getSelectedIndex()
getMinSelectionIndexgetMinSelectionIndex(),
addListSelectionListener(javax.swing.event.ListSelectionListener)public Object getSelectedValue()
null if the
selection is empty.getMinSelectionIndex(),
getModel(),
addListSelectionListener(javax.swing.event.ListSelectionListener)
public void setSelectedValue(Object anObject,
boolean shouldScroll)
anObject - the object to selectshouldScroll - true if the list should scroll to display
the selected object, if one exists; otherwise falsepublic Dimension getPreferredScrollableViewportSize()
visibleRowCount
rows. This is trivial if
fixedCellWidth and fixedCellHeight
were specified. Note that they can be specified implicitly with
the prototypeCellValue property.
If fixedCellWidth wasn't specified,
it's computed by finding the widest list element.
If fixedCellHeight
wasn't specified then we resort to heuristics:
visibleRowCount.
JList.getModel().getSize() == 0),
then we just allocate 16 pixels per visible row, and 256 pixels
for the width (unless fixedCellWidth was set),
and hope for the best.
getPreferredScrollableViewportSize in interface ScrollablevisibleRowCount rowsgetPreferredScrollableViewportSize(),
setPrototypeCellValue(java.lang.Object)
public int getScrollableUnitIncrement(Rectangle visibleRect,
int orientation,
int direction)
null.
We're using the font size instead of the width of some canonical string,
e.g. "m", because it's cheaper.
For verticaL scrolling: if we're scrolling downwards (direction is
greater than 0), and the first row is completely visible with respect
to visibleRect, then return its height. If
we're scrolling downwards and the first row is only partially visible,
return the height of the visible part of the first row. Similarly
if we're scrolling upwards we return the height of the row above
the first row, unless the first row is partially visible.
Note that the value of visibleRect must be the equal to
this.getVisibleRect().
getScrollableUnitIncrement in interface ScrollablevisibleRect - the visible rectangleorientation - HORIZONTAL or VERTICALdirection - if <= 0, then scroll UP; if > 0, then scroll DOWNIllegalArgumentException - if visibleRect is null, or
orientation isn't one of SwingConstants.VERTICAL,
SwingConstants.HORIZONTAL.- See Also:
Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)
public int getScrollableBlockIncrement(Rectangle visibleRect,
int orientation,
int direction)
getScrollableBlockIncrement in interface ScrollablevisibleRect - the visible rectangleorientation - HORIZONTAL or VERTICALdirection - if <= 0, then scroll UP; if > 0, then scroll DOWNIllegalArgumentException - if visibleRect is null, or
orientation isn't one of SwingConstants.VERTICAL,
SwingConstants.HORIZONTAL.Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)public boolean getScrollableTracksViewportWidth()
JList is displayed in a
JViewport and the viewport is wider than
JList's preferred width; otherwise returns false.
If false, then don't track the viewport's width. This allows horizontal
scrolling if the JViewport is itself embedded in a
JScrollPane.getScrollableTracksViewportWidth in interface ScrollableJList's
preferred width, otherwise falseScrollable.getScrollableTracksViewportWidth()public boolean getScrollableTracksViewportHeight()
JList is displayed in a
JViewport and the viewport is taller than
JList's preferred height; otherwise returns false.
If false, then don't track the viewport's height. This allows vertical
scrolling if the JViewport is itself embedded in a
JScrollPane.getScrollableTracksViewportHeight in interface ScrollableJlist's
preferred height, otherwise falseScrollable.getScrollableTracksViewportHeight()protected String paramString()
JList.
This method
is intended to be used only for debugging purposes, and the
content and format of the returned string may vary between
implementations. The returned string may be empty but may not
be null.paramString in class JComponentJList.public AccessibleContext getAccessibleContext()
getAccessibleContext in interface AccessiblegetAccessibleContext in class JComponent
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