/*
* Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
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*/
package javax.swing;
import java.awt.*;
import sun.awt.
ModalExclude;
import sun.awt.
SunToolkit;
/**
* Popups are used to display a <code>Component</code> to the user, typically
* on top of all the other <code>Component</code>s in a particular containment
* hierarchy. <code>Popup</code>s have a very small life cycle. Once you
* have obtained a <code>Popup</code>, and hidden it (invoked the
* <code>hide</code> method), you should no longer
* invoke any methods on it. This allows the <code>PopupFactory</code> to cache
* <code>Popup</code>s for later use.
* <p>
* The general contract is that if you need to change the size of the
* <code>Component</code>, or location of the <code>Popup</code>, you should
* obtain a new <code>Popup</code>.
* <p>
* <code>Popup</code> does not descend from <code>Component</code>, rather
* implementations of <code>Popup</code> are responsible for creating
* and maintaining their own <code>Component</code>s to render the
* requested <code>Component</code> to the user.
* <p>
* You typically do not explicitly create an instance of <code>Popup</code>,
* instead obtain one from a <code>PopupFactory</code>.
*
* @see PopupFactory
*
* @since 1.4
*/
public class
Popup {
/**
* The Component representing the Popup.
*/
private
Component component;
/**
* Creates a <code>Popup</code> for the Component <code>owner</code>
* containing the Component <code>contents</code>. <code>owner</code>
* is used to determine which <code>Window</code> the new
* <code>Popup</code> will parent the <code>Component</code> the
* <code>Popup</code> creates to.
* A null <code>owner</code> implies there is no valid parent.
* <code>x</code> and
* <code>y</code> specify the preferred initial location to place
* the <code>Popup</code> at. Based on screen size, or other paramaters,
* the <code>Popup</code> may not display at <code>x</code> and
* <code>y</code>.
*
* @param owner Component mouse coordinates are relative to, may be null
* @param contents Contents of the Popup
* @param x Initial x screen coordinate
* @param y Initial y screen coordinate
* @exception IllegalArgumentException if contents is null
*/
protected
Popup(
Component owner,
Component contents, int
x, int
y) {
this();
if (
contents == null) {
throw new
IllegalArgumentException("Contents must be non-null");
}
reset(
owner,
contents,
x,
y);
}
/**
* Creates a <code>Popup</code>. This is provided for subclasses.
*/
protected
Popup() {
}
/**
* Makes the <code>Popup</code> visible. If the <code>Popup</code> is
* currently visible, this has no effect.
*/
@
SuppressWarnings("deprecation")
public void
show() {
Component component =
getComponent();
if (
component != null) {
component.
show();
}
}
/**
* Hides and disposes of the <code>Popup</code>. Once a <code>Popup</code>
* has been disposed you should no longer invoke methods on it. A
* <code>dispose</code>d <code>Popup</code> may be reclaimed and later used
* based on the <code>PopupFactory</code>. As such, if you invoke methods
* on a <code>disposed</code> <code>Popup</code>, indeterminate
* behavior will result.
*/
@
SuppressWarnings("deprecation")
public void
hide() {
Component component =
getComponent();
if (
component instanceof
JWindow) {
component.
hide();
((
JWindow)
component).
getContentPane().
removeAll();
}
dispose();
}
/**
* Frees any resources the <code>Popup</code> may be holding onto.
*/
void
dispose() {
Component component =
getComponent();
Window window =
SwingUtilities.
getWindowAncestor(
component);
if (
component instanceof
JWindow) {
((
Window)
component).
dispose();
component = null;
}
// If our parent is a DefaultFrame, we need to dispose it, too.
if (
window instanceof
DefaultFrame) {
window.
dispose();
}
}
/**
* Resets the <code>Popup</code> to an initial state.
*/
void
reset(
Component owner,
Component contents, int
ownerX, int
ownerY) {
if (
getComponent() == null) {
component =
createComponent(
owner);
}
Component c =
getComponent();
if (
c instanceof
JWindow) {
JWindow component = (
JWindow)
getComponent();
component.
setLocation(
ownerX,
ownerY);
component.
getContentPane().
add(
contents,
BorderLayout.
CENTER);
component.
invalidate();
component.
validate();
if(
component.
isVisible()) {
// Do not call pack() if window is not visible to
// avoid early native peer creation
pack();
}
}
}
/**
* Causes the <code>Popup</code> to be sized to fit the preferred size
* of the <code>Component</code> it contains.
*/
void
pack() {
Component component =
getComponent();
if (
component instanceof
Window) {
((
Window)
component).
pack();
}
}
/**
* Returns the <code>Window</code> to use as the parent of the
* <code>Window</code> created for the <code>Popup</code>. This creates
* a new <code>DefaultFrame</code>, if necessary.
*/
private
Window getParentWindow(
Component owner) {
Window window = null;
if (
owner instanceof
Window) {
window = (
Window)
owner;
}
else if (
owner != null) {
window =
SwingUtilities.
getWindowAncestor(
owner);
}
if (
window == null) {
window = new
DefaultFrame();
}
return
window;
}
/**
* Creates the Component to use as the parent of the <code>Popup</code>.
* The default implementation creates a <code>Window</code>, subclasses
* should override.
*/
Component createComponent(
Component owner) {
if (
GraphicsEnvironment.
isHeadless()) {
// Generally not useful, bail.
return null;
}
return new
HeavyWeightWindow(
getParentWindow(
owner));
}
/**
* Returns the <code>Component</code> returned from
* <code>createComponent</code> that will hold the <code>Popup</code>.
*/
Component getComponent() {
return
component;
}
/**
* Component used to house window.
*/
static class
HeavyWeightWindow extends
JWindow implements
ModalExclude {
HeavyWeightWindow(
Window parent) {
super(
parent);
setFocusableWindowState(false);
setType(
Window.
Type.
POPUP);
// Popups are typically transient and most likely won't benefit
// from true double buffering. Turn it off here.
getRootPane().
setUseTrueDoubleBuffering(false);
// Try to set "always-on-top" for the popup window.
// Applets usually don't have sufficient permissions to do it.
// In this case simply ignore the exception.
try {
setAlwaysOnTop(true);
} catch (
SecurityException se) {
// setAlwaysOnTop is restricted,
// the exception is ignored
}
}
public void
update(
Graphics g) {
paint(
g);
}
public void
show() {
this.
pack();
if (
getWidth() > 0 &&
getHeight() > 0) {
super.show();
}
}
}
/**
* Used if no valid Window ancestor of the supplied owner is found.
* <p>
* PopupFactory uses this as a way to know when the Popup shouldn't
* be cached based on the Window.
*/
static class
DefaultFrame extends
Frame {
}
}