23 * questions. 24 */ 25 package sun.awt; 26 27 import java.awt.Component; 28 import java.awt.Rectangle; 29 import java.awt.event.PaintEvent; 30 31 /** 32 * PaintEventDispatcher is responsible for dispatching PaintEvents. There 33 * can be only one PaintEventDispatcher active at a particular time. 34 * 35 */ 36 public class PaintEventDispatcher { 37 /** 38 * Singleton dispatcher. 39 */ 40 private static PaintEventDispatcher dispatcher; 41 42 /** 43 * Sets the current <code>PaintEventDispatcher</code>. 44 * 45 * @param dispatcher PaintEventDispatcher 46 */ 47 public static void setPaintEventDispatcher( 48 PaintEventDispatcher dispatcher) { 49 synchronized(PaintEventDispatcher.class) { 50 PaintEventDispatcher.dispatcher = dispatcher; 51 } 52 } 53 54 /** 55 * Returns the currently active <code>PaintEventDispatcher</code>. This 56 * will never return null. 57 * 58 * @return PaintEventDispatcher 59 */ 60 public static PaintEventDispatcher getPaintEventDispatcher() { 61 synchronized(PaintEventDispatcher.class) { 62 if (dispatcher == null) { 63 dispatcher = new PaintEventDispatcher(); 64 } 65 return dispatcher; 66 } 67 } 68 69 /** 70 * Creates and returns the <code>PaintEvent</code> that should be 71 * dispatched for the specified component. If this returns null 72 * no <code>PaintEvent</code> is dispatched. 73 * <p> 74 * <b>WARNING:</b> This is invoked from the native thread, be careful 75 * what methods you end up invoking here. 76 */ 77 public PaintEvent createPaintEvent(Component target, int x, int y, int w, 78 int h) { 79 80 return new PaintEvent(target, PaintEvent.PAINT, 81 new Rectangle(x, y, w, h)); 82 } 83 84 /** 85 * Returns true if a native background erase should be done for 86 * the specified Component. 87 */ 88 public boolean shouldDoNativeBackgroundErase(Component c) { 89 return true; 90 } 91 92 /** | 23 * questions. 24 */ 25 package sun.awt; 26 27 import java.awt.Component; 28 import java.awt.Rectangle; 29 import java.awt.event.PaintEvent; 30 31 /** 32 * PaintEventDispatcher is responsible for dispatching PaintEvents. There 33 * can be only one PaintEventDispatcher active at a particular time. 34 * 35 */ 36 public class PaintEventDispatcher { 37 /** 38 * Singleton dispatcher. 39 */ 40 private static PaintEventDispatcher dispatcher; 41 42 /** 43 * Sets the current {@code PaintEventDispatcher}. 44 * 45 * @param dispatcher PaintEventDispatcher 46 */ 47 public static void setPaintEventDispatcher( 48 PaintEventDispatcher dispatcher) { 49 synchronized(PaintEventDispatcher.class) { 50 PaintEventDispatcher.dispatcher = dispatcher; 51 } 52 } 53 54 /** 55 * Returns the currently active {@code PaintEventDispatcher}. This 56 * will never return null. 57 * 58 * @return PaintEventDispatcher 59 */ 60 public static PaintEventDispatcher getPaintEventDispatcher() { 61 synchronized(PaintEventDispatcher.class) { 62 if (dispatcher == null) { 63 dispatcher = new PaintEventDispatcher(); 64 } 65 return dispatcher; 66 } 67 } 68 69 /** 70 * Creates and returns the {@code PaintEvent} that should be 71 * dispatched for the specified component. If this returns null 72 * no {@code PaintEvent} is dispatched. 73 * <p> 74 * <b>WARNING:</b> This is invoked from the native thread, be careful 75 * what methods you end up invoking here. 76 */ 77 public PaintEvent createPaintEvent(Component target, int x, int y, int w, 78 int h) { 79 80 return new PaintEvent(target, PaintEvent.PAINT, 81 new Rectangle(x, y, w, h)); 82 } 83 84 /** 85 * Returns true if a native background erase should be done for 86 * the specified Component. 87 */ 88 public boolean shouldDoNativeBackgroundErase(Component c) { 89 return true; 90 } 91 92 /** |