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Java Platform 1.2 Beta 4 |
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SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Object | +--java.awt.Component | +--java.awt.Container | +--java.awt.Window | +--java.awt.Frame | +--com.sun.java.swing.JFrame
The JFrame class is slightly incompatible with java.awt.Frame. JFrame contains a JRootPane as it's only child. The contentPane should be the parent of any children of the JFrame. This is different than java.awt.Frame, e.g. to add a child to an AWT Frame you'd write:
frame.add(child);However using JFrame you need to add the child to the JFrames contentPane instead:
frame.getContentPane().add(child);The same is true for setting LayoutManagers, removing components, listing children, etc. All these methods should normally be sent to the contentPane() instead of the JFrame itself. The contentPane() will always be non-null. Attempting to set it to null will cause the JFrame to throw an exception. The default contentPane() will have a BorderLayout manager set on it.
Please see the JRootPane documentation for a complete description of the contentPane, glassPane, and layeredPane properties.
Unlike its parent class, java.awt.Frame, you can tell a JFrame 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 setDefaultCloseOperation
.
To make the JFrame remain open unless you handle the window-closing event and
explicitly invoke dispose()
(or exit the app, which is also pretty
effective), use
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE)
.
That makes the JFrame behave the same as java.awt.Frame. A third option
lets you completely dispose of the window when it closes, instead of merely
hiding it.
For the keyboard keys used by this component in the standard Look and Feel (L&F) renditions, see the JFrame 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 Swing1.0 applications. It will not be possible to load serialized Swing1.0 objects with future releases of Swing. The JDK1.2 release of Swing will be the compatibility baseline for the serialized form of Swing objects.
JRootPane
,
setDefaultCloseOperation(int)
,
WindowListener.windowClosing(java.awt.event.WindowEvent)
, Serialized FormInner Class Summary | |
protected | JFrame.AccessibleJFrame
The class used to obtain the AccessibleRole for this object. |
Field Summary | |
protected AccessibleContext | accessibleContext
The accessible context property |
protected JRootPane | rootPane
The JRootPane instance that manages the contentPane
and optional menuBar for this frame, as well as the
glassPane . |
protected boolean | rootPaneCheckingEnabled
If true then calls to add and setLayout
cause an exception to be thrown. |
Fields inherited from class java.awt.Frame | |
CROSSHAIR_CURSOR , DEFAULT_CURSOR , E_RESIZE_CURSOR , HAND_CURSOR , MOVE_CURSOR , N_RESIZE_CURSOR , NE_RESIZE_CURSOR , NW_RESIZE_CURSOR , S_RESIZE_CURSOR , SE_RESIZE_CURSOR , SW_RESIZE_CURSOR , TEXT_CURSOR , W_RESIZE_CURSOR , WAIT_CURSOR |
Fields inherited from class java.awt.Component | |
BOTTOM_ALIGNMENT , CENTER_ALIGNMENT , LEFT_ALIGNMENT , RIGHT_ALIGNMENT , TOP_ALIGNMENT |
Constructor Summary | |
JFrame()
Constructs a new Frame that is initially invisible. |
|
JFrame(String title)
Constructs a new, initially invisible Frame with the specified title. |
Method Summary | |
protected void | addImpl(Component comp,
Object constraints,
int index)
By default, children may not be added directly to a this component, they must be added to its contentPane instead. |
protected JRootPane | createRootPane()
Called by the constructor methods to create the default rootPane. |
protected void | frameInit()
Called by the constructors to init the JFrame properly. |
AccessibleContext | getAccessibleContext()
Get the AccessibleContext associated with this JFrame |
Container | getContentPane()
Returns the contentPane object for this frame. |
int | getDefaultCloseOperation()
Returns the operation which occurs when the user initiates a "close" on this frame. |
Component | getGlassPane()
Returns the glassPane object for this frame. |
JMenuBar | getJMenuBar()
Returns the menubar set on this frame. |
JLayeredPane | getLayeredPane()
Returns the layeredPane object for this frame. |
JRootPane | getRootPane()
Returns the rootPane object for this frame. |
protected boolean | isRootPaneCheckingEnabled()
Returns whether calls to add and
setLayout cause an exception to be thrown. |
protected void | processKeyEvent(KeyEvent e)
Processes key events occurring on this component and, if appropriate, passes them on to components in the frame which have registered interest in them. |
protected void | processWindowEvent(WindowEvent e)
Processes window events occurring on this component. |
void | setContentPane(Container contentPane)
Sets the contentPane property. |
void | setDefaultCloseOperation(int operation)
Sets the operation which will happen by default when the user initiates a "close" on this frame. |
void | setGlassPane(Component glassPane)
Sets the glassPane property. |
void | setJMenuBar(JMenuBar menubar)
Sets the menubar for this frame. |
void | setLayeredPane(JLayeredPane layeredPane)
Sets the layeredPane property. |
void | setLayout(LayoutManager manager)
By default the layout of this component may not be set, the layout of its contentPane should be set instead. |
protected void | setRootPane(JRootPane root)
Sets the rootPane property. |
protected void | setRootPaneCheckingEnabled(boolean enabled)
Determines whether calls to add and
setLayout cause an exception to be thrown. |
void | update(Graphics g)
Just calls paint(g) . |
Methods inherited from class java.awt.Frame | |
addNotify , dispose , finalize , getCursorType , getFrames , getIconImage , getMenuBar , getTitle , isResizable , paramString , remove , setCursor , setIconImage , setMenuBar , setResizable , setTitle |
Methods inherited from class java.awt.Window | |
addWindowListener , applyResourceBundle , applyResourceBundle , getFocusOwner , getInputContext , getLocale , getOwnedWindows , getOwner , getToolkit , getWarningString , isShowing , pack , postEvent , processEvent , removeWindowListener , show , toBack , toFront |
Methods inherited from class java.awt.Container | |
add , add , add , add , add , addContainerListener , countComponents , deliverEvent , doLayout , findComponentAt , findComponentAt , getAlignmentX , getAlignmentY , getComponent , getComponentAt , getComponentAt , getComponentCount , getComponents , getInsets , getLayout , getMaximumSize , getMinimumSize , getPreferredSize , insets , invalidate , isAncestorOf , layout , list , list , locate , minimumSize , paint , paintComponents , preferredSize , print , printComponents , processContainerEvent , remove , remove , removeAll , removeContainerListener , removeNotify , validate , validateTree |
Methods inherited from class java.lang.Object | |
clone , equals , getClass , hashCode , notify , notifyAll , wait , wait , wait |
Field Detail |
protected JRootPane rootPane
contentPane
and optional menuBar
for this frame, as well as the
glassPane
.JRootPane
,
RootPaneContainer
protected boolean rootPaneCheckingEnabled
add
and setLayout
cause an exception to be thrown.isRootPaneCheckingEnabled()
,
setRootPaneCheckingEnabled(boolean)
protected AccessibleContext accessibleContext
Constructor Detail |
public JFrame()
Component.setSize(int, int)
,
Component.setVisible(boolean)
public JFrame(String title)
title
- the title for the frameComponent.setSize(int, int)
,
Component.setVisible(boolean)
Method Detail |
protected void frameInit()
protected JRootPane createRootPane()
protected void processKeyEvent(KeyEvent e)
e
- the key eventComponent.processKeyEvent(java.awt.event.KeyEvent)
protected void processWindowEvent(WindowEvent e)
defaultCloseOperation
property.
e
- the window eventsetDefaultCloseOperation(int)
,
Window.processWindowEvent(java.awt.event.WindowEvent)
public void setDefaultCloseOperation(int operation)
WindowConstants
interface:
The value is set to HIDE_ON_CLOSE by default.
Window.addWindowListener(java.awt.event.WindowListener)
,
getDefaultCloseOperation()
public int getDefaultCloseOperation()
setDefaultCloseOperation(int)
public void update(Graphics g)
paint(g)
. This method was overridden to
prevent an unneccessary call to clear the background.
g
- the Graphics context in which to paintpublic void setJMenuBar(JMenuBar menubar)
menubar
- the menubar being placed in the framegetJMenuBar()
public JMenuBar getJMenuBar()
setJMenuBar(com.sun.java.swing.JMenuBar)
protected boolean isRootPaneCheckingEnabled()
add
and
setLayout
cause an exception to be thrown.add
and setLayout
are checkedaddImpl(java.awt.Component, java.lang.Object, int)
,
setLayout(java.awt.LayoutManager)
,
setRootPaneCheckingEnabled(boolean)
protected void setRootPaneCheckingEnabled(boolean enabled)
add
and
setLayout
cause an exception to be thrown.
enabled
- a boolean value, true if checking is to be
enabled, which cause the exceptions to be thrownaddImpl(java.awt.Component, java.lang.Object, int)
,
setLayout(java.awt.LayoutManager)
,
isRootPaneCheckingEnabled()
protected void addImpl(Component comp, Object constraints, int index)
thisComponent.getContentPane().add(child)An attempt to add to directly to this component will cause an runtime exception to be thrown. Subclasses can disable this behavior.
setRootPaneCheckingEnabled(boolean)
public void setLayout(LayoutManager manager)
thiComponent.getContentPane().setLayout(new BorderLayout())An attempt to set the layout of this component will cause an runtime exception to be thrown. Subclasses can disable this behavior.
setRootPaneCheckingEnabled(boolean)
public JRootPane getRootPane()
setRootPane(com.sun.java.swing.JRootPane)
,
RootPaneContainer.getRootPane()
protected void setRootPane(JRootPane root)
root
- the rootPane object for this framegetRootPane()
public Container getContentPane()
setContentPane(java.awt.Container)
,
RootPaneContainer.getContentPane()
public void setContentPane(Container contentPane)
contentPane
- the contentPane object for this framegetContentPane()
,
RootPaneContainer.setContentPane(java.awt.Container)
public JLayeredPane getLayeredPane()
setLayeredPane(com.sun.java.swing.JLayeredPane)
,
RootPaneContainer.getLayeredPane()
public void setLayeredPane(JLayeredPane layeredPane)
layeredPane
- the layeredPane object for this framegetLayeredPane()
,
RootPaneContainer.setLayeredPane(com.sun.java.swing.JLayeredPane)
public Component getGlassPane()
setGlassPane(java.awt.Component)
,
RootPaneContainer.getGlassPane()
public void setGlassPane(Component glassPane)
glassPane
- the glassPane object for this framegetGlassPane()
,
RootPaneContainer.setGlassPane(java.awt.Component)
public AccessibleContext getAccessibleContext()
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Java Platform 1.2 Beta 4 |
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SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |