public class

JDesktopPane

extends JLayeredPane
implements Accessible
java.lang.Object
   ↳ java.awt.Component
     ↳ java.awt.Container
       ↳ javax.swing.JComponent
         ↳ javax.swing.JLayeredPane
           ↳ javax.swing.JDesktopPane

Class Overview

A container used to create a multiple-document interface or a virtual desktop. You create JInternalFrame objects and add them to the JDesktopPane. JDesktopPane extends JLayeredPane to manage the potentially overlapping internal frames. It also maintains a reference to an instance of DesktopManager that is set by the UI class for the current look and feel (L&F). Note that JDesktopPane does not support borders.

This class is normally used as the parent of JInternalFrames to provide a pluggable DesktopManager object to the JInternalFrames. The installUI of the L&F specific implementation is responsible for setting the desktopManager variable appropriately. When the parent of a JInternalFrame is a JDesktopPane, it should delegate most of its behavior to the desktopManager (closing, resizing, etc).

For further documentation and examples see How to Use Internal Frames, a section in The Java Tutorial.

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 see XMLEncoder.

Summary

Nested Classes
class JDesktopPane.AccessibleJDesktopPane This class implements accessibility support for the JDesktopPane class. 
Constants
int LIVE_DRAG_MODE Indicates that the entire contents of the item being dragged should appear inside the desktop pane.
int OUTLINE_DRAG_MODE Indicates that an outline only of the item being dragged should appear inside the desktop pane.
[Expand]
Inherited Constants
From class javax.swing.JLayeredPane
From class javax.swing.JComponent
From class java.awt.Component
From interface java.awt.image.ImageObserver
[Expand]
Inherited Fields
From class javax.swing.JLayeredPane
From class javax.swing.JComponent
Public Constructors
JDesktopPane()
Creates a new JDesktopPane.
Public Methods
AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this JDesktopPane.
JInternalFrame[] getAllFrames()
Returns all JInternalFrames currently displayed in the desktop.
JInternalFrame[] getAllFramesInLayer(int layer)
Returns all JInternalFrames currently displayed in the specified layer of the desktop.
DesktopManager getDesktopManager()
Returns the DesktopManger that handles desktop-specific UI actions.
int getDragMode()
Gets the current "dragging style" used by the desktop pane.
JInternalFrame getSelectedFrame()
Returns the currently active JInternalFrame in this JDesktopPane, or null if no JInternalFrame is currently active.
DesktopPaneUI getUI()
Returns the L&F object that renders this component.
String getUIClassID()
Returns the name of the L&F class that renders this component.
void remove(int index)
Remove the indexed component from this pane.
void removeAll()
Removes all the components from this container.
JInternalFrame selectFrame(boolean forward)
Selects the next JInternalFrame in this desktop pane.
void setComponentZOrder(Component comp, int index)
Moves the specified component to the specified z-order index in the container.
void setDesktopManager(DesktopManager d)
Sets the DesktopManger that will handle desktop-specific UI actions.
void setDragMode(int dragMode)
Sets the "dragging style" used by the desktop pane.
void setSelectedFrame(JInternalFrame f)
Sets the currently active JInternalFrame in this JDesktopPane.
void setUI(DesktopPaneUI ui)
Sets the L&F object that renders this component.
void updateUI()
Notification from the UIManager that the L&F has changed.
Protected Methods
void addImpl(Component comp, Object constraints, int index)
Adds the specified component to this container at the specified index.
String paramString()
Returns a string representation of this JDesktopPane.
[Expand]
Inherited Methods
From class javax.swing.JLayeredPane
From class javax.swing.JComponent
From class java.awt.Container
From class java.awt.Component
From class java.lang.Object
From interface java.awt.MenuContainer
From interface java.awt.image.ImageObserver
From interface javax.accessibility.Accessible

Constants

public static final int LIVE_DRAG_MODE

Indicates that the entire contents of the item being dragged should appear inside the desktop pane.

Constant Value: 0 (0x00000000)

public static final int OUTLINE_DRAG_MODE

Indicates that an outline only of the item being dragged should appear inside the desktop pane.

Constant Value: 1 (0x00000001)

Public Constructors

public JDesktopPane ()

Creates a new JDesktopPane.

Public Methods

public AccessibleContext getAccessibleContext ()

Gets the AccessibleContext associated with this JDesktopPane. For desktop panes, the AccessibleContext takes the form of an AccessibleJDesktopPane. A new AccessibleJDesktopPane instance is created if necessary.

Returns
  • an AccessibleJDesktopPane that serves as the AccessibleContext of this JDesktopPane

public JInternalFrame[] getAllFrames ()

Returns all JInternalFrames currently displayed in the desktop. Returns iconified frames as well as expanded frames.

Returns
  • an array of JInternalFrame objects

public JInternalFrame[] getAllFramesInLayer (int layer)

Returns all JInternalFrames currently displayed in the specified layer of the desktop. Returns iconified frames as well expanded frames.

Parameters
layer an int specifying the desktop layer
Returns
  • an array of JInternalFrame objects
See Also

public DesktopManager getDesktopManager ()

Returns the DesktopManger that handles desktop-specific UI actions.

public int getDragMode ()

Gets the current "dragging style" used by the desktop pane.

Returns
  • either Live_DRAG_MODE or OUTLINE_DRAG_MODE
See Also

public JInternalFrame getSelectedFrame ()

Returns the currently active JInternalFrame in this JDesktopPane, or null if no JInternalFrame is currently active.

Returns
  • the currently active JInternalFrame or null

public DesktopPaneUI getUI ()

Returns the L&F object that renders this component.

Returns
  • the DesktopPaneUI object that renders this component

public String getUIClassID ()

Returns the name of the L&F class that renders this component.

Returns
  • the string "DesktopPaneUI"

public void remove (int index)

Remove the indexed component from this pane. This is the absolute index, ignoring layers.

Parameters
index an int specifying the component to remove

public void removeAll ()

Removes all the components from this container.

public JInternalFrame selectFrame (boolean forward)

Selects the next JInternalFrame in this desktop pane.

Parameters
forward a boolean indicating which direction to select in; true for forward, false for backward
Returns
  • the JInternalFrame that was selected or null if nothing was selected

public void setComponentZOrder (Component comp, int index)

Moves the specified component to the specified z-order index in the container. The z-order determines the order that components are painted; the component with the highest z-order paints first and the component with the lowest z-order paints last. Where components overlap, the component with the lower z-order paints over the component with the higher z-order.

If the component is a child of some other container, it is removed from that container before being added to this container. The important difference between this method and java.awt.Container.add(Component, int) is that this method doesn't call removeNotify on the component while removing it from its previous container unless necessary and when allowed by the underlying native windowing system. This way, if the component has the keyboard focus, it maintains the focus when moved to the new position.

This property is guaranteed to apply only to lightweight non-Container components.

Note: Not all platforms support changing the z-order of heavyweight components from one container into another without the call to removeNotify. There is no way to detect whether a platform supports this, so developers shouldn't make any assumptions.

Parameters
comp the component to be moved
index the position in the container's list to insert the component, where getComponentCount() appends to the end

public void setDesktopManager (DesktopManager d)

Sets the DesktopManger that will handle desktop-specific UI actions.

Parameters
d the DesktopManager to use

public void setDragMode (int dragMode)

Sets the "dragging style" used by the desktop pane. You may want to change to one mode or another for performance or aesthetic reasons.

Parameters
dragMode the style of drag to use for items in the Desktop

public void setSelectedFrame (JInternalFrame f)

Sets the currently active JInternalFrame in this JDesktopPane. This method is used to bridge the package gap between JDesktopPane and the platform implementation code and should not be called directly. To visually select the frame the client must call JInternalFrame.setSelected(true) to activate the frame.

Parameters
f the internal frame that's currently selected

public void setUI (DesktopPaneUI ui)

Sets the L&F object that renders this component.

Parameters
ui the DesktopPaneUI L&F object

public void updateUI ()

Notification from the UIManager that the L&F has changed. Replaces the current UI object with the latest version from the UIManager.

See Also

Protected Methods

protected void addImpl (Component comp, Object constraints, int index)

Adds the specified component to this container at the specified index. This method also notifies the layout manager to add the component to this container's layout using the specified constraints object via the addLayoutComponent method.

The constraints are defined by the particular layout manager being used. For example, the BorderLayout class defines five constraints: BorderLayout.NORTH, BorderLayout.SOUTH, BorderLayout.EAST, BorderLayout.WEST, and BorderLayout.CENTER.

The GridBagLayout class requires a GridBagConstraints object. Failure to pass the correct type of constraints object results in an IllegalArgumentException.

If the current layout manager implements LayoutManager2, then addLayoutComponent(Component, Object) is invoked on it. If the current layout manager does not implement LayoutManager2, and constraints is a String, then addLayoutComponent(String, Component) is invoked on it.

If the component is not an ancestor of this container and has a non-null parent, it is removed from its current parent before it is added to this container.

This is the method to override if a program needs to track every add request to a container as all other add methods defer to this one. An overriding method should usually include a call to the superclass's version of the method:

super.addImpl(comp, constraints, index)

Parameters
comp the component to be added
constraints an object expressing layout constraints for this component
index the position in the container's list at which to insert the component, where -1 means append to the end

protected String paramString ()

Returns a string representation of this JDesktopPane. 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.

Returns
  • a string representation of this JDesktopPane