/*
* Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
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.
*/
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.
*/
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);
contents.invalidate();
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);
Toolkit tk = Toolkit.getDefaultToolkit();
if (tk instanceof SunToolkit) {
// all the short-lived windows like Popups should be
// OverrideRedirect on X11 platforms
((SunToolkit)tk).setOverrideRedirect(this);
}
// 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 {
}
}