1 /* SwingContainerPeer.java -- A Swing based peer for AWT containers 2 Copyright (C) 2006, 2007 Free Software Foundation, Inc. 3 4 This file is part of GNU Classpath. 5 6 GNU Classpath is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU Classpath is distributed in the hope that it will be useful, but 12 WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GNU Classpath; see the file COPYING. If not, write to the 18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19 02110-1301 USA. 20 21 Linking this library statically or dynamically with other modules is 22 making a combined work based on this library. Thus, the terms and 23 conditions of the GNU General Public License cover the whole 24 combination. 25 26 As a special exception, the copyright holders of this library give you 27 permission to link this library with independent modules to produce an 28 executable, regardless of the license terms of these independent 29 modules, and to copy and distribute the resulting executable under 30 terms of your choice, provided that you also meet, for each linked 31 independent module, the terms and conditions of the license of that 32 module. An independent module is a module which is not derived from 33 or based on this library. If you modify this library, you may extend 34 this exception to your version of the library, but you are not 35 obligated to do so. If you do not wish to do so, delete this 36 exception statement from your version. */ 37 38 package gnu.java.awt.peer.swing; 39 40 import gnu.classpath.SystemProperties; 41 42 import java.awt.Component; 43 import java.awt.Container; 44 import java.awt.Graphics; 45 import java.awt.Image; 46 import java.awt.Insets; 47 import java.awt.Rectangle; 48 import java.awt.event.KeyEvent; 49 import java.awt.event.MouseEvent; 50 import java.awt.peer.ComponentPeer; 51 import java.awt.peer.ContainerPeer; 52 import java.util.Iterator; 53 import java.util.LinkedList; 54 55 /** 56 * A peer for Container to be used with the Swing based AWT peers. 57 * 58 * @author Roman Kennke (kennke@aicas.com) 59 */ 60 public class SwingContainerPeer 61 extends SwingComponentPeer 62 implements ContainerPeer 63 { 64 65 /** 66 * Stores all heavyweight descendents of the container. This is used 67 * in {@link #peerPaintChildren(Graphics)}. 68 */ 69 private LinkedList heavyweightDescendents; 70 71 /** 72 * The backbuffer used for painting UPDATE events. 73 */ 74 private Image backbuffer; 75 76 /** 77 * Creates a new SwingContainerPeer. 78 * 79 * @param awtCont 80 */ SwingContainerPeer(Container awtCont)81 public SwingContainerPeer(Container awtCont) 82 { 83 heavyweightDescendents = new LinkedList(); 84 } 85 86 /** 87 * Registers a heavyweight descendent. This is then painted by 88 * {@link #peerPaintChildren(Graphics)}. 89 * 90 * @param comp the descendent to register 91 * 92 * @see #peerPaintChildren(Graphics) 93 * @see #removeHeavyweightDescendent(Component) 94 */ addHeavyweightDescendent(Component comp)95 protected synchronized void addHeavyweightDescendent(Component comp) 96 { 97 heavyweightDescendents.add(comp); 98 focusOwner = null; 99 } 100 101 /** 102 * Unregisters a heavyweight descendent. 103 * 104 * @param comp the descendent to unregister 105 * 106 * @see #peerPaintChildren(Graphics) 107 * @see #addHeavyweightDescendent(Component) 108 */ removeHeavyweightDescendent(Component comp)109 protected synchronized void removeHeavyweightDescendent(Component comp) 110 { 111 heavyweightDescendents.remove(comp); 112 focusOwner = null; 113 } 114 115 /** 116 * Returns an array of all registered heavyweight descendents. 117 * 118 * @return all registered heavyweight descendents 119 */ getHeavyweightDescendents()120 protected Component[] getHeavyweightDescendents() 121 { 122 Component[] heavyweights = new Component[heavyweightDescendents.size()]; 123 heavyweights = (Component[]) heavyweightDescendents.toArray(heavyweights); 124 return heavyweights; 125 } 126 127 /** 128 * Returns the insets of the container. 129 * 130 * This is implemented to return the insets of the Swing container. 131 * 132 * @return the insets of the container 133 */ insets()134 public Insets insets() 135 { 136 Insets retVal; 137 if (swingComponent != null) 138 retVal = swingComponent.getJComponent().getInsets(); 139 else 140 retVal = new Insets(0, 0, 0, 0); 141 return retVal; 142 } 143 144 /** 145 * Returns the insets of the container. 146 * 147 * This is implemented to return the insets of the Swing container. 148 * 149 * @return the insets of the container 150 */ getInsets()151 public Insets getInsets() 152 { 153 return insets(); 154 } 155 156 /** 157 * Called before the validation of this containers begins. 158 */ beginValidate()159 public void beginValidate() 160 { 161 // Nothing to do here. 162 } 163 164 /** 165 * Called after the validation of this containers ended. 166 */ endValidate()167 public void endValidate() 168 { 169 // Nothing to do here. 170 } 171 172 /** 173 * Called before the layout of this containers begins. 174 */ beginLayout()175 public void beginLayout() 176 { 177 // Nothing to do here. 178 } 179 180 /** 181 * Called after the layout of this containers ended. 182 */ endLayout()183 public void endLayout() 184 { 185 // Nothing to do here. 186 } 187 188 /** 189 * Returns <code>false</code> unconditionally. This method is not used at 190 * the moment. 191 * 192 * @return <code>false</code> 193 */ isPaintPending()194 public boolean isPaintPending() 195 { 196 return false; 197 } 198 199 /** 200 * Returns <code>false</code> unconditionally. This method is not used at 201 * the moment. 202 * 203 * @return <code>false</code> 204 */ isRestackSupported()205 public boolean isRestackSupported() 206 { 207 return false; 208 } 209 210 /** 211 * This method is not used at the moment. 212 */ cancelPendingPaint(int x, int y, int width, int height)213 public void cancelPendingPaint(int x, int y, int width, int height) 214 { 215 // Nothing to do here. 216 } 217 218 /** 219 * This method is not used at the moment. 220 */ restack()221 public void restack() 222 { 223 // Nothing to do here. 224 } 225 226 /** 227 * Performs the super behaviour (call peerPaintComponent() and 228 * awtComponent.paint()), and forwards the paint request to the heavyweight 229 * descendents of the container. 230 */ peerPaint(Graphics g, boolean update)231 protected void peerPaint(Graphics g, boolean update) 232 { 233 if (isDoubleBuffering()) 234 { 235 int width = awtComponent.getWidth(); 236 int height = awtComponent.getHeight(); 237 if (backbuffer == null 238 || backbuffer.getWidth(awtComponent) < width 239 || backbuffer.getHeight(awtComponent) < height) 240 backbuffer = awtComponent.createImage(width, height); 241 Graphics g2 = backbuffer.getGraphics(); 242 Rectangle clip = g.getClipRect(); 243 try 244 { 245 g2.setClip(clip); 246 super.peerPaint(g2, update); 247 peerPaintChildren(g2); 248 } 249 finally 250 { 251 g2.dispose(); 252 } 253 g.drawImage(backbuffer, 0, 0, awtComponent); 254 } 255 else 256 { 257 super.peerPaint(g, update); 258 peerPaintChildren(g); 259 } 260 } 261 262 /** 263 * Determines if we should do double buffering or not. 264 * 265 * @return if we should do double buffering or not 266 */ isDoubleBuffering()267 private boolean isDoubleBuffering() 268 { 269 Object prop = 270 SystemProperties.getProperty("gnu.awt.swing.doublebuffering", "false"); 271 return prop.equals("true"); 272 } 273 274 /** 275 * Paints any heavyweight child components. 276 * 277 * @param g the graphics to use for painting 278 */ peerPaintChildren(Graphics g)279 protected synchronized void peerPaintChildren(Graphics g) 280 { 281 // TODO: Is this the right painting order? 282 for (Iterator i = heavyweightDescendents.iterator(); i.hasNext();) 283 { 284 Component child = (Component) i.next(); 285 ComponentPeer peer = child.getPeer(); 286 287 if (peer instanceof SwingComponentPeer && child.isVisible()) 288 { 289 // TODO: The translation here doesn't work for deeper 290 // nested children. Fix this! 291 Graphics g2 = g.create(child.getX(), child.getY(), 292 child.getWidth(), child.getHeight()); 293 try 294 { 295 // update() is only called for the topmost component if 296 // necessary, all other components only get paint() called. 297 ((SwingComponentPeer) peer).peerPaint(g2, false); 298 } 299 finally 300 { 301 g2.dispose(); 302 } 303 } 304 } 305 } 306 307 /** 308 * Handles mouse events by dispatching it to the correct component. 309 * 310 * @param ev the mouse event 311 */ handleMouseEvent(MouseEvent ev)312 protected void handleMouseEvent(MouseEvent ev) 313 { 314 Component comp = awtComponent.getComponentAt(ev.getPoint()); 315 if(comp == null) comp = awtComponent; 316 ComponentPeer peer = comp.getPeer(); 317 if (awtComponent != comp && !comp.isLightweight() && peer instanceof SwingComponentPeer) 318 { 319 ev.translatePoint(comp.getX(), comp.getY()); 320 ev.setSource(comp); 321 ((SwingComponentPeer) peer).handleMouseEvent(ev); 322 } 323 } 324 325 /** 326 * Handles mouse events by dispatching it to the correct component. 327 * 328 * @param ev the mouse event 329 */ handleMouseMotionEvent(MouseEvent ev)330 protected void handleMouseMotionEvent(MouseEvent ev) 331 { 332 Component comp = awtComponent.getComponentAt(ev.getPoint()); 333 if (comp != null) 334 { 335 ComponentPeer peer = comp.getPeer(); 336 if (awtComponent != comp && !comp.isLightweight() && peer instanceof SwingComponentPeer) 337 { 338 ev.translatePoint(comp.getX(), comp.getY()); 339 ((SwingComponentPeer) peer).handleMouseMotionEvent(ev); 340 } 341 } 342 } 343 344 /** 345 * Handles key events on the component. This is usually forwarded to the 346 * SwingComponent's processKeyEvent() method. 347 * 348 * @param e the key event 349 */ handleKeyEvent(KeyEvent e)350 protected void handleKeyEvent(KeyEvent e) 351 { 352 Component owner = getFocusOwner(); 353 if(owner != null) 354 owner.getPeer().handleEvent(e); 355 else 356 super.handleKeyEvent(e); 357 } 358 359 private Component focusOwner = null; 360 getFocusOwner()361 private Component getFocusOwner() 362 { 363 if(focusOwner == null) 364 { 365 for(Iterator iter=heavyweightDescendents.iterator(); iter.hasNext();) 366 { 367 Component child = (Component) iter.next(); 368 if(child.isFocusable()) 369 { 370 focusOwner = child; 371 break; 372 } 373 } 374 } 375 return focusOwner; 376 } 377 378 } 379