java.awt.Frame that adds support for
* the JFC/Swing component architecture.
* You can find task-oriented documentation about using JFrame
* in The Java Tutorial, in the section
* How to Make Frames.
*
*
* The JFrame class is slightly incompatible with Frame.
* Like all other JFC/Swing top-level containers,
* a JFrame contains a JRootPane as its only child.
* The content pane provided by the root pane should,
* as a rule, contain
* all the non-menu components displayed by the JFrame.
* This is different from the AWT Frame case.
* As a conveniance add and its variants, remove and
* setLayout have been overridden to forward to the
* contentPane as necessary. This means you can write:
*
* frame.add(child); ** And the child will be added to the contentPane. * The content pane will * always be non-null. Attempting to set it to null will cause the JFrame * to throw an exception. The default content pane will have a BorderLayout * manager set on it. * Refer to {@link javax.swing.RootPaneContainer} * for details on adding, removing and setting the
LayoutManager
* of a JFrame.
*
* Unlike a Frame, a JFrame has some notion of how to
* respond when the user attempts to close the window. The default behavior
* is to simply hide the JFrame when the user closes the window. To change the
* default behavior, you invoke the method
* {@link #setDefaultCloseOperation}.
* To make the JFrame behave the same as a Frame
* instance, use
* setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE).
*
* For more information on content panes * and other features that root panes provide, * see Using Top-Level Containers in The Java Tutorial. *
* In a multi-screen environment, you can create a JFrame
* on a different screen device. See {@link java.awt.Frame} for more
* information.
*
* 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 {@link java.beans.XMLEncoder}.
*
* @see JRootPane
* @see #setDefaultCloseOperation
* @see java.awt.event.WindowListener#windowClosing
* @see javax.swing.RootPaneContainer
*
* @beaninfo
* attribute: isContainer true
* attribute: containerDelegate getContentPane
* description: A toplevel window which can be minimized to an icon.
*
* @author Jeff Dinkins
* @author Georges Saab
* @author David Kloba
*/
public class JFrame extends Frame implements WindowConstants,
Accessible,
RootPaneContainer,
TransferHandler.HasGetTransferHandler
{
/**
* The exit application default window close operation. If a window
* has this set as the close operation and is closed in an applet,
* a SecurityException may be thrown.
* It is recommended you only use this in an application.
*
* @since 1.3
*/
public static final int EXIT_ON_CLOSE = 3;
/**
* Key into the AppContext, used to check if should provide decorations
* by default.
*/
private static final Object defaultLookAndFeelDecoratedKey =
new StringBuffer("JFrame.defaultLookAndFeelDecorated");
private int defaultCloseOperation = HIDE_ON_CLOSE;
/**
* The TransferHandler for this frame.
*/
private TransferHandler transferHandler;
/**
* The JRootPane instance that manages the
* contentPane
* and optional menuBar for this frame, as well as the
* glassPane.
*
* @see JRootPane
* @see RootPaneContainer
*/
protected JRootPane rootPane;
/**
* If true then calls to add and setLayout
* will be forwarded to the contentPane. This is initially
* false, but is set to true when the JFrame is constructed.
*
* @see #isRootPaneCheckingEnabled
* @see #setRootPaneCheckingEnabled
* @see javax.swing.RootPaneContainer
*/
protected boolean rootPaneCheckingEnabled = false;
/**
* Constructs a new frame that is initially invisible.
*
* This constructor sets the component's locale property to the value
* returned by JComponent.getDefaultLocale.
*
* @exception HeadlessException if GraphicsEnvironment.isHeadless()
* returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
* @see Component#setSize
* @see Component#setVisible
* @see JComponent#getDefaultLocale
*/
public JFrame() throws HeadlessException {
super();
frameInit();
}
/**
* Creates a Frame in the specified
* GraphicsConfiguration of
* a screen device and a blank title.
*
* This constructor sets the component's locale property to the value
* returned by JComponent.getDefaultLocale.
*
* @param gc the GraphicsConfiguration that is used
* to construct the new Frame;
* if gc is null, the system
* default GraphicsConfiguration is assumed
* @exception IllegalArgumentException if gc is not from
* a screen device. This exception is always thrown when
* GraphicsEnvironment.isHeadless() returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
* @see JComponent#getDefaultLocale
* @since 1.3
*/
public JFrame(GraphicsConfiguration gc) {
super(gc);
frameInit();
}
/**
* Creates a new, initially invisible Frame with the
* specified title.
*
* This constructor sets the component's locale property to the value
* returned by JComponent.getDefaultLocale.
*
* @param title the title for the frame
* @exception HeadlessException if GraphicsEnvironment.isHeadless()
* returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
* @see Component#setSize
* @see Component#setVisible
* @see JComponent#getDefaultLocale
*/
public JFrame(String title) throws HeadlessException {
super(title);
frameInit();
}
/**
* Creates a JFrame with the specified title and the
* specified GraphicsConfiguration of a screen device.
*
* This constructor sets the component's locale property to the value
* returned by JComponent.getDefaultLocale.
*
* @param title the title to be displayed in the
* frame's border. A null value is treated as
* an empty string, "".
* @param gc the GraphicsConfiguration that is used
* to construct the new JFrame with;
* if gc is null, the system
* default GraphicsConfiguration is assumed
* @exception IllegalArgumentException if gc is not from
* a screen device. This exception is always thrown when
* GraphicsEnvironment.isHeadless() returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
* @see JComponent#getDefaultLocale
* @since 1.3
*/
public JFrame(String title, GraphicsConfiguration gc) {
super(title, gc);
frameInit();
}
/** Called by the constructors to init the JFrame properly. */
protected void frameInit() {
enableEvents(AWTEvent.KEY_EVENT_MASK | AWTEvent.WINDOW_EVENT_MASK);
setLocale( JComponent.getDefaultLocale() );
setRootPane(createRootPane());
setBackground(UIManager.getColor("control"));
setRootPaneCheckingEnabled(true);
if (JFrame.isDefaultLookAndFeelDecorated()) {
boolean supportsWindowDecorations =
UIManager.getLookAndFeel().getSupportsWindowDecorations();
if (supportsWindowDecorations) {
setUndecorated(true);
getRootPane().setWindowDecorationStyle(JRootPane.FRAME);
}
}
sun.awt.SunToolkit.checkAndSetPolicy(this);
}
/**
* Called by the constructor methods to create the default
* rootPane.
*/
protected JRootPane createRootPane() {
JRootPane rp = new JRootPane();
// NOTE: this uses setOpaque vs LookAndFeel.installProperty as there
// is NO reason for the RootPane not to be opaque. For painting to
// work the contentPane must be opaque, therefor the RootPane can
// also be opaque.
rp.setOpaque(true);
return rp;
}
/**
* Processes window events occurring on this component.
* Hides the window or disposes of it, as specified by the setting
* of the defaultCloseOperation property.
*
* @param e the window event
* @see #setDefaultCloseOperation
* @see java.awt.Window#processWindowEvent
*/
protected void processWindowEvent(WindowEvent e) {
super.processWindowEvent(e);
if (e.getID() == WindowEvent.WINDOW_CLOSING) {
switch(defaultCloseOperation) {
case HIDE_ON_CLOSE:
setVisible(false);
break;
case DISPOSE_ON_CLOSE:
dispose();
break;
case DO_NOTHING_ON_CLOSE:
default:
break;
case EXIT_ON_CLOSE:
// This needs to match the checkExit call in
// setDefaultCloseOperation
System.exit(0);
break;
}
}
}
// public void setMenuBar(MenuBar menu) {
// throw new IllegalComponentStateException("Please use setJMenuBar() with JFrame.");
// }
/**
* Sets the operation that will happen by default when
* the user initiates a "close" on this frame.
* You must specify one of the following choices:
*
*
DO_NOTHING_ON_CLOSE
* (defined in WindowConstants):
* Don't do anything; require the
* program to handle the operation in the windowClosing
* method of a registered WindowListener object.
*
* HIDE_ON_CLOSE
* (defined in WindowConstants):
* Automatically hide the frame after
* invoking any registered WindowListener
* objects.
*
* DISPOSE_ON_CLOSE
* (defined in WindowConstants):
* Automatically hide and dispose the
* frame after invoking any registered WindowListener
* objects.
*
* EXIT_ON_CLOSE
* (defined in JFrame):
* Exit the application using the System
* exit method. Use this only in applications.
*
* The value is set to HIDE_ON_CLOSE by default. Changes
* to the value of this property cause the firing of a property
* change event, with property name "defaultCloseOperation".
*
* Note: When the last displayable window within the
* Java virtual machine (VM) is disposed of, the VM may
* terminate. See
* AWT Threading Issues for more information.
*
* @param operation the operation which should be performed when the
* user closes the frame
* @exception IllegalArgumentException if defaultCloseOperation value
* isn't one of the above valid values
* @see #addWindowListener
* @see #getDefaultCloseOperation
* @see WindowConstants
* @throws SecurityException
* if EXIT_ON_CLOSE has been specified and the
* SecurityManager will
* not allow the caller to invoke System.exit
* @see java.lang.Runtime#exit(int)
*
* @beaninfo
* preferred: true
* bound: true
* enum: DO_NOTHING_ON_CLOSE WindowConstants.DO_NOTHING_ON_CLOSE
* HIDE_ON_CLOSE WindowConstants.HIDE_ON_CLOSE
* DISPOSE_ON_CLOSE WindowConstants.DISPOSE_ON_CLOSE
* EXIT_ON_CLOSE WindowConstants.EXIT_ON_CLOSE
* description: The frame's default close operation.
*/
public void setDefaultCloseOperation(int operation) {
if (operation != DO_NOTHING_ON_CLOSE &&
operation != HIDE_ON_CLOSE &&
operation != DISPOSE_ON_CLOSE &&
operation != EXIT_ON_CLOSE) {
throw new IllegalArgumentException("defaultCloseOperation must be one of: DO_NOTHING_ON_CLOSE, HIDE_ON_CLOSE, DISPOSE_ON_CLOSE, or EXIT_ON_CLOSE");
}
if (this.defaultCloseOperation != operation) {
if (operation == EXIT_ON_CLOSE) {
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkExit(0);
}
}
int oldValue = this.defaultCloseOperation;
this.defaultCloseOperation = operation;
firePropertyChange("defaultCloseOperation", oldValue, operation);
}
}
/**
* Returns the operation that occurs when the user
* initiates a "close" on this frame.
*
* @return an integer indicating the window-close operation
* @see #setDefaultCloseOperation
*/
public int getDefaultCloseOperation() {
return defaultCloseOperation;
}
/**
* Sets the {@code transferHandler} property, which is a mechanism to
* support transfer of data into this component. Use {@code null}
* if the component does not support data transfer operations.
*
* If the system property {@code suppressSwingDropSupport} is {@code false} * (the default) and the current drop target on this component is either * {@code null} or not a user-set drop target, this method will change the * drop target as follows: If {@code newHandler} is {@code null} it will * clear the drop target. If not {@code null} it will install a new * {@code DropTarget}. *
* Note: When used with {@code JFrame}, {@code TransferHandler} only * provides data import capability, as the data export related methods * are currently typed to {@code JComponent}. *
* Please see
*
* How to Use Drag and Drop and Data Transfer, a section in
* The Java Tutorial, for more information.
*
* @param newHandler the new {@code TransferHandler}
*
* @see TransferHandler
* @see #getTransferHandler
* @see java.awt.Component#setDropTarget
* @since 1.6
*
* @beaninfo
* bound: true
* hidden: true
* description: Mechanism for transfer of data into the component
*/
public void setTransferHandler(TransferHandler newHandler) {
TransferHandler oldHandler = transferHandler;
transferHandler = newHandler;
SwingUtilities.installSwingDropTargetAsNecessary(this, transferHandler);
firePropertyChange("transferHandler", oldHandler, newHandler);
}
/**
* Gets the transferHandler property.
*
* @return the value of the transferHandler property
*
* @see TransferHandler
* @see #setTransferHandler
* @since 1.6
*/
public TransferHandler getTransferHandler() {
return transferHandler;
}
/**
* Just calls paint(g). This method was overridden to
* prevent an unnecessary call to clear the background.
*
* @param g the Graphics context in which to paint
*/
public void update(Graphics g) {
paint(g);
}
/**
* Sets the menubar for this frame.
* @param menubar the menubar being placed in the frame
*
* @see #getJMenuBar
*
* @beaninfo
* hidden: true
* description: The menubar for accessing pulldown menus from this frame.
*/
public void setJMenuBar(JMenuBar menubar) {
getRootPane().setMenuBar(menubar);
}
/**
* Returns the menubar set on this frame.
* @return the menubar for this frame
*
* @see #setJMenuBar
*/
public JMenuBar getJMenuBar() {
return getRootPane().getMenuBar();
}
/**
* Returns whether calls to add and
* setLayout are forwarded to the contentPane.
*
* @return true if add and setLayout
* are fowarded; false otherwise
*
* @see #addImpl
* @see #setLayout
* @see #setRootPaneCheckingEnabled
* @see javax.swing.RootPaneContainer
*/
protected boolean isRootPaneCheckingEnabled() {
return rootPaneCheckingEnabled;
}
/**
* Sets whether calls to add and
* setLayout are forwarded to the contentPane.
*
* @param enabled true if add and setLayout
* are forwarded, false if they should operate directly on the
* JFrame.
*
* @see #addImpl
* @see #setLayout
* @see #isRootPaneCheckingEnabled
* @see javax.swing.RootPaneContainer
* @beaninfo
* hidden: true
* description: Whether the add and setLayout methods are forwarded
*/
protected void setRootPaneCheckingEnabled(boolean enabled) {
rootPaneCheckingEnabled = enabled;
}
/**
* Adds the specified child Component.
* This method is overridden to conditionally forward calls to the
* contentPane.
* By default, children are added to the contentPane instead
* of the frame, refer to {@link javax.swing.RootPaneContainer} for
* details.
*
* @param comp the component to be enhanced
* @param constraints the constraints to be respected
* @param index the index
* @exception IllegalArgumentException if index is invalid
* @exception IllegalArgumentException if adding the container's parent
* to itself
* @exception IllegalArgumentException if adding a window to a container
*
* @see #setRootPaneCheckingEnabled
* @see javax.swing.RootPaneContainer
*/
protected void addImpl(Component comp, Object constraints, int index)
{
if(isRootPaneCheckingEnabled()) {
getContentPane().add(comp, constraints, index);
}
else {
super.addImpl(comp, constraints, index);
}
}
/**
* Removes the specified component from the container. If
* comp is not the rootPane, this will forward
* the call to the contentPane. This will do nothing if
* comp is not a child of the JFrame or
* contentPane.
*
* @param comp the component to be removed
* @throws NullPointerException if comp is null
* @see #add
* @see javax.swing.RootPaneContainer
*/
public void remove(Component comp) {
if (comp == rootPane) {
super.remove(comp);
} else {
getContentPane().remove(comp);
}
}
/**
* Sets the LayoutManager.
* Overridden to conditionally forward the call to the
* contentPane.
* Refer to {@link javax.swing.RootPaneContainer} for
* more information.
*
* @param manager the LayoutManager
* @see #setRootPaneCheckingEnabled
* @see javax.swing.RootPaneContainer
*/
public void setLayout(LayoutManager manager) {
if(isRootPaneCheckingEnabled()) {
getContentPane().setLayout(manager);
}
else {
super.setLayout(manager);
}
}
/**
* Returns the rootPane object for this frame.
* @return the rootPane property
*
* @see #setRootPane
* @see RootPaneContainer#getRootPane
*/
public JRootPane getRootPane() {
return rootPane;
}
/**
* Sets the rootPane property.
* This method is called by the constructor.
* @param root the rootPane object for this frame
*
* @see #getRootPane
*
* @beaninfo
* hidden: true
* description: the RootPane object for this frame.
*/
protected void setRootPane(JRootPane root)
{
if(rootPane != null) {
remove(rootPane);
}
rootPane = root;
if(rootPane != null) {
boolean checkingEnabled = isRootPaneCheckingEnabled();
try {
setRootPaneCheckingEnabled(false);
add(rootPane, BorderLayout.CENTER);
}
finally {
setRootPaneCheckingEnabled(checkingEnabled);
}
}
}
/**
* {@inheritDoc}
*/
public void setIconImage(Image image) {
super.setIconImage(image);
}
/**
* Returns the contentPane object for this frame.
* @return the contentPane property
*
* @see #setContentPane
* @see RootPaneContainer#getContentPane
*/
public Container getContentPane() {
return getRootPane().getContentPane();
}
/**
* Sets the contentPane property.
* This method is called by the constructor.
*
* Swing's painting architecture requires an opaque JComponent
* in the containment hiearchy. This is typically provided by the
* content pane. If you replace the content pane it is recommended you
* replace it with an opaque JComponent.
*
* @param contentPane the contentPane object for this frame
*
* @exception java.awt.IllegalComponentStateException (a runtime
* exception) if the content pane parameter is null
* @see #getContentPane
* @see RootPaneContainer#setContentPane
* @see JRootPane
*
* @beaninfo
* hidden: true
* description: The client area of the frame where child
* components are normally inserted.
*/
public void setContentPane(Container contentPane) {
getRootPane().setContentPane(contentPane);
}
/**
* Returns the layeredPane object for this frame.
* @return the layeredPane property
*
* @see #setLayeredPane
* @see RootPaneContainer#getLayeredPane
*/
public JLayeredPane getLayeredPane() {
return getRootPane().getLayeredPane();
}
/**
* Sets the layeredPane property.
* This method is called by the constructor.
* @param layeredPane the layeredPane object for this frame
*
* @exception java.awt.IllegalComponentStateException (a runtime
* exception) if the layered pane parameter is null
* @see #getLayeredPane
* @see RootPaneContainer#setLayeredPane
*
* @beaninfo
* hidden: true
* description: The pane that holds the various frame layers.
*/
public void setLayeredPane(JLayeredPane layeredPane) {
getRootPane().setLayeredPane(layeredPane);
}
/**
* Returns the glassPane object for this frame.
* @return the glassPane property
*
* @see #setGlassPane
* @see RootPaneContainer#getGlassPane
*/
public Component getGlassPane() {
return getRootPane().getGlassPane();
}
/**
* Sets the glassPane property.
* This method is called by the constructor.
* @param glassPane the glassPane object for this frame
*
* @see #getGlassPane
* @see RootPaneContainer#setGlassPane
*
* @beaninfo
* hidden: true
* description: A transparent pane used for menu rendering.
*/
public void setGlassPane(Component glassPane) {
getRootPane().setGlassPane(glassPane);
}
/**
* {@inheritDoc}
*
* @since 1.6
*/
public Graphics getGraphics() {
JComponent.getGraphicsInvoked(this);
return super.getGraphics();
}
/**
* Repaints the specified rectangle of this component within
* time milliseconds. Refer to RepaintManager
* for details on how the repaint is handled.
*
* @param time maximum time in milliseconds before update
* @param x the x coordinate
* @param y the y coordinate
* @param width the width
* @param height the height
* @see RepaintManager
* @since 1.6
*/
public void repaint(long time, int x, int y, int width, int height) {
if (RepaintManager.HANDLE_TOP_LEVEL_PAINT) {
RepaintManager.currentManager(this).addDirtyRegion(
this, x, y, width, height);
}
else {
super.repaint(time, x, y, width, height);
}
}
/**
* Provides a hint as to whether or not newly created JFrames
* should have their Window decorations (such as borders, widgets to
* close the window, title...) provided by the current look
* and feel. If defaultLookAndFeelDecorated is true,
* the current LookAndFeel supports providing window
* decorations, and the current window manager supports undecorated
* windows, then newly created JFrames will have their
* Window decorations provided by the current LookAndFeel.
* Otherwise, newly created JFrames will have their
* Window decorations provided by the current window manager.
*
* You can get the same effect on a single JFrame by doing the following: *
* JFrame frame = new JFrame();
* frame.setUndecorated(true);
* frame.getRootPane().setWindowDecorationStyle(JRootPane.FRAME);
*
*
* @param defaultLookAndFeelDecorated A hint as to whether or not current
* look and feel should provide window decorations
* @see javax.swing.LookAndFeel#getSupportsWindowDecorations
* @since 1.4
*/
public static void setDefaultLookAndFeelDecorated(boolean defaultLookAndFeelDecorated) {
if (defaultLookAndFeelDecorated) {
SwingUtilities.appContextPut(defaultLookAndFeelDecoratedKey, Boolean.TRUE);
} else {
SwingUtilities.appContextPut(defaultLookAndFeelDecoratedKey, Boolean.FALSE);
}
}
/**
* Returns true if newly created JFrames should have their
* Window decorations provided by the current look and feel. This is only
* a hint, as certain look and feels may not support this feature.
*
* @return true if look and feel should provide Window decorations.
* @since 1.4
*/
public static boolean isDefaultLookAndFeelDecorated() {
Boolean defaultLookAndFeelDecorated =
(Boolean) SwingUtilities.appContextGet(defaultLookAndFeelDecoratedKey);
if (defaultLookAndFeelDecorated == null) {
defaultLookAndFeelDecorated = Boolean.FALSE;
}
return defaultLookAndFeelDecorated.booleanValue();
}
/**
* Returns a string representation of this JFrame.
* 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.
*
* @return a string representation of this JFrame
*/
protected String paramString() {
String defaultCloseOperationString;
if (defaultCloseOperation == HIDE_ON_CLOSE) {
defaultCloseOperationString = "HIDE_ON_CLOSE";
} else if (defaultCloseOperation == DISPOSE_ON_CLOSE) {
defaultCloseOperationString = "DISPOSE_ON_CLOSE";
} else if (defaultCloseOperation == DO_NOTHING_ON_CLOSE) {
defaultCloseOperationString = "DO_NOTHING_ON_CLOSE";
} else if (defaultCloseOperation == 3) {
defaultCloseOperationString = "EXIT_ON_CLOSE";
} else defaultCloseOperationString = "";
String rootPaneString = (rootPane != null ?
rootPane.toString() : "");
String rootPaneCheckingEnabledString = (rootPaneCheckingEnabled ?
"true" : "false");
return super.paramString() +
",defaultCloseOperation=" + defaultCloseOperationString +
",rootPane=" + rootPaneString +
",rootPaneCheckingEnabled=" + rootPaneCheckingEnabledString;
}
/////////////////
// Accessibility support
////////////////
/** The accessible context property. */
protected AccessibleContext accessibleContext = null;
/**
* Gets the AccessibleContext associated with this JFrame.
* For JFrames, the AccessibleContext takes the form of an
* AccessibleJFrame.
* A new AccessibleJFrame instance is created if necessary.
*
* @return an AccessibleJFrame that serves as the
* AccessibleContext of this JFrame
*/
public AccessibleContext getAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = new AccessibleJFrame();
}
return accessibleContext;
}
/**
* This class implements accessibility support for the
* JFrame class. It provides an implementation of the
* Java Accessibility API appropriate to frame user-interface
* elements.
*/
protected class AccessibleJFrame extends AccessibleAWTFrame {
// AccessibleContext methods
/**
* Get the accessible name of this object.
*
* @return the localized name of the object -- can be null if this
* object does not have a name
*/
public String getAccessibleName() {
if (accessibleName != null) {
return accessibleName;
} else {
if (getTitle() == null) {
return super.getAccessibleName();
} else {
return getTitle();
}
}
}
/**
* Get the state of this object.
*
* @return an instance of AccessibleStateSet containing the current
* state set of the object
* @see AccessibleState
*/
public AccessibleStateSet getAccessibleStateSet() {
AccessibleStateSet states = super.getAccessibleStateSet();
if (isResizable()) {
states.add(AccessibleState.RESIZABLE);
}
if (getFocusOwner() != null) {
states.add(AccessibleState.ACTIVE);
}
// FIXME: [[[WDW - should also return ICONIFIED and ICONIFIABLE
// if we can ever figure these out]]]
return states;
}
} // inner class AccessibleJFrame
}