windowutils.java

java实现浏览器等本地桌面的功能

/*
 * $Id: WindowUtils.java,v 1.5 2005/10/10 18:03:00 rbair Exp $
 *
 * Copyright 2004 Sun Microsystems, Inc., 4150 Network Circle,
 * Santa Clara, California 95054, U.S.A. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library 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
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
package org.jdesktop.swingx.util;

import java.awt.Component;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.GridBagConstraints;
import java.awt.Insets;
import java.awt.MouseInfo;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Window;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentListener;

import javax.swing.JComponent;
import javax.swing.JDesktopPane;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JInternalFrame;
import javax.swing.RootPaneContainer;
import javax.swing.SwingUtilities;

/**
 * Encapsulates various utilities for windows (ie: <code>Frame</code> and
 * <code>Dialog</code> objects and descendants, in particular).
 * @author Richard Bair
 */
public final class WindowUtils {
	
	/**
	 * Hide the constructor - don't wan't anybody creating an instance of this
	 */
	private WindowUtils() {
	}
	
	/**
	 * <p>
	 * Returns the <code>Point</code> at which a window should be placed to
	 * center that window on the screen.
	 * </p>
	 * <p>
	 * Some thought was taken as to whether to implement a method such as this,
	 * or to simply make a method that, given a window, will center it.  It was
	 * decided that it is better to not alter an object within a method.
	 * </p>
	 * @param window The window to calculate the center point for.  This object
	 * can not be null.
	 * @return the <code>Point</code> at which the window should be placed to
	 * center that window on the screen.
	 */
	public static Point getPointForCentering(Window window) {
		//assert window != null;
        try {
            Point mousePoint = MouseInfo.getPointerInfo().getLocation();
            GraphicsDevice[] devices = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices();
            for (GraphicsDevice device : devices) {
                Rectangle bounds = device.getDefaultConfiguration().getBounds();
                //check to see if the mouse cursor is within these bounds
                if (mousePoint.x >= bounds.x && mousePoint.y >= bounds.y
                        && mousePoint.x <= (bounds.x + bounds.width)
                        && mousePoint.y <= (bounds.y + bounds.height)) {
                    //this is it
                    int screenWidth = bounds.width;
                    int screenHeight = bounds.height;
                    int width = window.getWidth();
                    int height = window.getHeight();
                    Point p = new Point(((screenWidth - width) / 2) + bounds.x, ((screenHeight - height) / 2) + bounds.y);
                    return p;
                }
            }
        } catch (Exception e) {
            //this can occur do to a Security exception in sandboxed apps
            e.printStackTrace();
        }
		return new Point(0,0);
	}
	
	/**
	 * <p>
	 * Returns the <code>Point</code> at which a window should be placed to
	 * center that window on the given desktop.
	 * </p>
	 * <p>
	 * Some thought was taken as to whether to implement a method such as this,
	 * or to simply make a method that, given a window, will center it.  It was
	 * decided that it is better to not alter an object within a method.
	 * </p>
	 * @param window The window (JInternalFrame) to calculate the center point
	 * for.  This object can not be null.
	 * @param desktop The JDesktopPane that houses this window.
	 * @return the <code>Point</code> at which the window should be placed to
	 * center that window on the given desktop
	 */
	public static Point getPointForCentering(JInternalFrame window, JDesktopPane desktop) {
        try {
            //assert window != null;
            Point mousePoint = MouseInfo.getPointerInfo().getLocation();
            GraphicsDevice[] devices = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices();
            for (GraphicsDevice device : devices) {
                Rectangle bounds = device.getDefaultConfiguration().getBounds();
                //check to see if the mouse cursor is within these bounds
                if (mousePoint.x >= bounds.x && mousePoint.y >= bounds.y
                        && mousePoint.x <= (bounds.x + bounds.width)
                        && mousePoint.y <= (bounds.y + bounds.height)) {
                    //this is it
                    int screenWidth = bounds.width;
                    int screenHeight = bounds.height;
                    int width = window.getWidth();
                    int height = window.getHeight();
                    Point p = new Point(((screenWidth - width) / 2) + bounds.x, ((screenHeight - height) / 2) + bounds.y);
                    return p;
                }
            }
        } catch (Exception e) {
            //this can occur do to a Security exception in sandboxed apps
            e.printStackTrace();
        }
		return new Point(0,0);
	}
 
        /**
         *<p>
	 * Returns the <code>Point</code> at which a window should be placed in
         * order to be staggered slightly from another &quot;origin&quot; window to 
         * ensure that the title areas of both windows remain visible to the user.
	 * </p> 
         * @param originWindow Window from which the staggered location will be calculated
         * @return location staggered from the upper left location of the origin
         *         window
         */ 
        public static Point getPointForStaggering(Window originWindow) {
            Point origin = originWindow.getLocation();
            Insets insets = originWindow.getInsets();
            origin.x += insets.top;
            origin.y += insets.top;
            return origin;
        }

	/**
	 * Utility method used to load a GridBagConstraints object (param gbc) with the
	 * data in the other parameters.  This method saves code space over doing the
	 * assignments by hand, and also allows you to reuse the same GridBagConstraints
	 * object reducing temporary object creating (at the expense of a method call.
	 * Go figure).
	 */
	public static void setConstraints(GridBagConstraints gbc, int gridx, int gridy, int gridwidth, int gridheight,
	 double weightx, double weighty, int anchor, int fill, int top, int left, int bottom, int right) {
		gbc.gridx = gridx;
		gbc.gridy = gridy;
		gbc.gridwidth = gridwidth;
		gbc.gridheight = gridheight;
		gbc.weightx = weightx;
		gbc.weighty = weighty;
		gbc.anchor = anchor;
		gbc.fill = fill;
		gbc.insets = new Insets(top, left, bottom, right);
	}
	
	/**
	 * Get a <code>Spatial</code> object representing the given window's position and
	 * magnitude in space.
	 * @param win The window to get a Spatial object for
	 * @return a Spatial object.  @see com.jgui.Spatial
	 */
	public static Spatial getSpatial(Window win) {
		Spatial spatial = new Spatial(win.getY(), win.getX(), win.getWidth(), win.getHeight());
		return spatial;
	}

	/**
	 * Get a <code>Spatial</code> object representing the given JComponent's position and
	 * magnitude in space.
	 * @param comp The JComponent to get a Spatial object for
	 * @return a Spatial object.  @see com.jgui.Spatial
	 */
	public static Spatial getSpatial(JComponent comp) {
		Spatial spatial = new Spatial(comp.getY(), comp.getX(), comp.getWidth(), comp.getHeight());
		return spatial;
	}
	
	/**
	 * Locates the RootPaneContainer for the given component
	 * @param c
	 * @return
	 */
	public static RootPaneContainer findRootPaneContainer(Component c) {
		if (c == null) {
			return null;
		} else if (c instanceof RootPaneContainer) {
			return (RootPaneContainer)c;
		} else {
			return findRootPaneContainer(c.getParent());
		}
	}

	/**
	 * Locates the JFrame for the given component
	 * @param c
	 * @return
	 */
	public static JFrame findJFrame(Component c) {
		if (c == null) {
			return null;
		} else if (c instanceof RootPaneContainer) {
			return (JFrame)c;
		} else {
			return findJFrame(c.getParent());
		}
	}

	/**
	 * Locates the JDialog for the given component
	 * @param c
	 * @return
	 */
	public static JDialog findJDialog(Component c) {
		if (c == null) {
			return null;
		} else if (c instanceof JDialog) {
			return (JDialog)c;
		} else {
			return findJDialog(c.getParent());
		}
	}

    /**
     * 
     * Installs/resets a ComponentListener to resize the
     * given window to minWidth/Height if needed.
     * 
     * @param window
     * @param minWidth
     * @param minHeight
     */
    public static void setMinimumSizeManager(Window window, int minWidth,
            int minHeight) {
        ComponentListener[] listeners = window.getComponentListeners();
        ComponentListener listener = null;
        boolean found = false;
        for (ComponentListener l : listeners) {
            if (l instanceof MinSizeComponentListener) {
                listener = l;
                break;
            }
        }
        if (listener == null) {
            window.addComponentListener(new MinSizeComponentListener(
                            window, minWidth, minHeight));
        } else {
            ((MinSizeComponentListener) listener).resetSizes(minWidth,
                    minHeight);
        }
    }
    
    /**
     * Resets window size to minSize if needed.
     * 
     * @author Patrick Wright
     */
    public static class MinSizeComponentListener extends ComponentAdapter {
        private Window window;

        private int minHeight;

        private int minWidth;

        MinSizeComponentListener(Window frame, int minWidth, int minHeight) {
            this.window = frame;
            resetSizes(minWidth, minHeight);
        }

        public void resetSizes(int minWidth, int minHeight) {
            this.minWidth = minWidth;
            this.minHeight = minHeight;
            adjustIfNeeded(window);
        }

        public void componentResized(java.awt.event.ComponentEvent evt) {
            adjustIfNeeded((Window) evt.getComponent());
        }

        private void adjustIfNeeded(final Window window) {
            boolean doSize = false;
            int newWidth = window.getWidth();
            int newHeight = window.getHeight();

            if (newWidth < minWidth) {
                newWidth = minWidth;
                doSize = true;
            }
            if (newHeight < minHeight) {
                newHeight = minHeight;
                doSize = true;
            }
            if (doSize) {
                final int w = newWidth;
                final int h = newHeight;
                SwingUtilities.invokeLater(new Runnable() {
                    public void run() {
                        window.setSize(w, h);
                    }
                });
            }
        }
    }

}