1 /*
   2  * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.awt;
  27 
  28 import java.awt.Container;
  29 import java.awt.Frame;
  30 import java.awt.Graphics;
  31 import java.awt.Image;
  32 import java.awt.MenuBar;
  33 import java.awt.MenuComponent;
  34 import java.awt.Rectangle;
  35 import java.awt.Toolkit;
  36 import java.awt.peer.FramePeer;
  37 
  38 /**
  39  * The class provides basic functionality for a lightweight frame
  40  * implementation. A subclass is expected to provide painting to an
  41  * offscreen image and access to it. Thus it can be used for lightweight
  42  * embedding.
  43  *
  44  * @author Artem Ananiev
  45  * @author Anton Tarasov
  46  */
  47 @SuppressWarnings("serial")
  48 public abstract class LightweightFrame extends Frame {
  49 
  50     /**
  51      * Constructs a new, initially invisible {@code LightweightFrame}
  52      * instance.
  53      */
  54     public LightweightFrame() {
  55         setUndecorated(true);
  56         setResizable(true);
  57         setEnabled(true);
  58     }
  59 
  60     /**
  61      * Blocks introspection of a parent window by this child.
  62      *
  63      * @return null
  64      */
  65     @Override public final Container getParent() { return null; }
  66 
  67     @Override public Graphics getGraphics() { return null; }
  68 
  69     @Override public final boolean isResizable() { return true; }
  70 
  71     // Block modification of any frame attributes, since they aren't
  72     // applicable for a lightweight frame.
  73 
  74     @Override public final void setTitle(String title) {}
  75     @Override public final void setIconImage(Image image) {}
  76     @Override public final void setIconImages(java.util.List<? extends Image> icons) {}
  77     @Override public final void setMenuBar(MenuBar mb) {}
  78     @Override public final void setResizable(boolean resizable) {}
  79     @Override public final void remove(MenuComponent m) {}
  80     @Override public final void toFront() {}
  81     @Override public final void toBack() {}
  82 
  83     @Override public void addNotify() {
  84         synchronized (getTreeLock()) {
  85             if (getPeer() == null) {
  86                 SunToolkit stk = (SunToolkit)Toolkit.getDefaultToolkit();
  87                 try {
  88                     setPeer(stk.createLightweightFrame(this));
  89                 } catch (Exception e) {
  90                     throw new RuntimeException(e);
  91                 }
  92             }
  93             super.addNotify();
  94         }
  95     }
  96 
  97     private void setPeer(final FramePeer p) {
  98         AWTAccessor.getComponentAccessor().setPeer(this, p);
  99     }
 100 
 101     /**
 102      * Requests the peer to emulate activation or deactivation of the
 103      * frame. Peers should override this method if they are to implement
 104      * this functionality.
 105      *
 106      * @param activate if <code>true</code>, activates the frame;
 107      *                 otherwise, deactivates the frame
 108      */
 109     public void emulateActivation(boolean activate) {
 110         ((FramePeer)getPeer()).emulateActivation(activate);
 111     }
 112 
 113     /**
 114      * Delegates the focus grab action to the client (embedding) application.
 115      * The method is called by the AWT grab machinery.
 116      *
 117      * @see SunToolkit#grab(java.awt.Window)
 118      */
 119     public abstract void grabFocus();
 120 
 121     /**
 122      * Delegates the focus ungrab action to the client (embedding) application.
 123      * The method is called by the AWT grab machinery.
 124      *
 125      * @see SunToolkit#ungrab(java.awt.Window)
 126      */
 127     public abstract void ungrabFocus();
 128 
 129     /**
 130      * Returns the scale factor of this frame. The default value is 1.
 131      *
 132      * @return the scale factor
 133      * @see #notifyDisplayChanged(int)
 134      */
 135     public abstract int getScaleFactor();
 136 
 137     /**
 138      * Called when display of the hosted frame is changed.
 139      *
 140      * @param scaleFactor the scale factor
 141      */
 142     public abstract void notifyDisplayChanged(int scaleFactor);
 143 
 144     /**
 145      * Host window absolute bounds.
 146      */
 147     private int hostX, hostY, hostW, hostH;
 148 
 149     /**
 150      * Returns the absolute bounds of the host (embedding) window.
 151      *
 152      * @return the host window bounds
 153      */
 154     public Rectangle getHostBounds() {
 155         if (hostX == 0 && hostY == 0 && hostW == 0 && hostH == 0) {
 156             // The client app is probably unaware of the setHostBounds.
 157             // A safe fall-back:
 158             return getBounds();
 159         }
 160         return new Rectangle(hostX, hostY, hostW, hostH);
 161     }
 162 
 163     /**
 164      * Sets the absolute bounds of the host (embedding) window.
 165      */
 166     public void setHostBounds(int x, int y, int w, int h) {
 167         hostX = x;
 168         hostY = y;
 169         hostW = w;
 170         hostH = h;
 171     }
 172 }