| package org.eclipse.swt.widgets; |
| |
| /* |
| * (c) Copyright IBM Corp. 2000, 2001. |
| * All Rights Reserved |
| */ |
| |
| import org.eclipse.swt.internal.gtk.*; |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| |
| /** |
| * Instances of this class provide a surface for drawing |
| * arbitrary graphics. |
| * <dl> |
| * <dt><b>Styles:</b></dt> |
| * <dd>(none)</dd> |
| * <dt><b>Events:</b></dt> |
| * <dd>(none)</dd> |
| * </dl> |
| * <p> |
| * This class may be subclassed by custom control implementors |
| * who are building controls that are <em>not</em> constructed |
| * from aggregates of other controls. That is, they are either |
| * painted using SWT graphics calls or are handled by native |
| * methods. |
| * </p> |
| * |
| * @see Composite |
| */ |
| public class Canvas extends Composite { |
| |
| Caret caret; |
| |
| /* |
| * === CONSTRUCTORS === |
| */ |
| |
| |
| Canvas () {} |
| |
| /** |
| * Constructs a new instance of this class given its parent |
| * and a style value describing its behavior and appearance. |
| * <p> |
| * The style value is either one of the style constants defined in |
| * class <code>SWT</code> which is applicable to instances of this |
| * class, or must be built by <em>bitwise OR</em>'ing together |
| * (that is, using the <code>int</code> "|" operator) two or more |
| * of those <code>SWT</code> style constants. The class description |
| * for all SWT widget classes should include a comment which |
| * describes the style constants which are applicable to the class. |
| * </p> |
| * |
| * @param parent a composite control which will be the parent of the new instance (cannot be null) |
| * @param style the style of control to construct |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the parent is null</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> |
| * <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> |
| * </ul> |
| * |
| * @see SWT |
| * @see Widget#checkSubclass |
| * @see Widget#getStyle |
| */ |
| public Canvas (Composite parent, int style) { |
| super (parent, style); |
| } |
| |
| /** |
| * Returns the caret. |
| * <p> |
| * The caret for the control is automatically hidden |
| * and shown when the control is painted or resized, |
| * when focus is gained or lost and when an the control |
| * is scrolled. To avoid drawing on top of the caret, |
| * the programmer must hide and show the caret when |
| * drawing in the window any other time. |
| * </p> |
| * |
| * @return the caret |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public Caret getCaret () { |
| checkWidget(); |
| return caret; |
| } |
| |
| /** |
| * Scrolls a rectangular area of the receiver by first copying |
| * the source area to the destination and then causing the area |
| * of the source which is not covered by the destination to |
| * be repainted. Children that intersect the rectangle are |
| * optionally moved during the operation. In addition, outstanding |
| * paint events are flushed before the source area is copied to |
| * ensure that the contents of the canvas are drawn correctly. |
| * |
| * @param destX the x coordinate of the destination |
| * @param destY the y coordinate of the destination |
| * @param x the x coordinate of the source |
| * @param y the y coordinate of the source |
| * @param width the width of the area |
| * @param height the height of the area |
| * @param all <code>true</code>if children should be scrolled, and <code>false</code> otherwise |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public void scroll (int destX, int destY, int x, int y, int width, int height, boolean all) { |
| if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); |
| if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); |
| |
| if (width <= 0 || height <= 0) return; |
| int deltaX = destX - x, deltaY = destY - y; |
| if (deltaX == 0 && deltaY == 0) return; |
| if (!isVisible ()) return; |
| |
| /* Hide the caret */ |
| boolean isVisible = (caret != null) && (caret.isVisible ()); |
| if (isVisible) caret.hideCaret (); |
| |
| GtkWidget widget = new GtkWidget(); |
| OS.memmove (widget, paintHandle(), GtkWidget.sizeof); |
| int window = widget.window; |
| if (window == 0) return; |
| |
| /* Emit a NoExpose Event */ |
| int gc = OS.gdk_gc_new (window); |
| OS.gdk_gc_set_exposures(gc, true); |
| OS.gdk_window_copy_area (window, gc, x, y, window, x, y, width, height); |
| OS.gdk_gc_destroy (gc); |
| |
| /* Flush outstanding Exposes */ |
| int eventHandle=0; |
| while ((eventHandle = OS.gdk_event_get_graphics_expose(window)) != 0) { |
| OS.gtk_widget_event(handle, eventHandle); |
| OS.gdk_event_free(eventHandle); |
| } |
| |
| /* Scroll the window */ |
| int gc1 = OS.gdk_gc_new (window); |
| OS.gdk_gc_set_exposures(gc1, true); |
| OS.gdk_window_copy_area (window, gc1, destX, destY, window, x, y, width, height); |
| OS.gdk_gc_destroy (gc1); |
| boolean disjoint = (destX + width < x) || (x + width < destX) || (destY + height < y) || (y + height < destY); |
| if (disjoint) { |
| OS.gdk_window_clear_area(window, x, y, width, height); |
| } else { |
| if (deltaX != 0) { |
| int newX = destX - deltaX; |
| if (deltaX < 0) newX = destX + width; |
| OS.gdk_window_clear_area_e(window, newX, y, Math.abs (deltaX), height); |
| } |
| if (deltaY != 0) { |
| int newY = destY - deltaY; |
| if (deltaY < 0) newY = destY + height; |
| OS.gdk_window_clear_area_e (window, x, newY, width, Math.abs (deltaY)); |
| } |
| } |
| |
| /* Show the caret */ |
| if (isVisible) caret.showCaret (); |
| } |
| /** |
| * Sets the receiver's caret. |
| * <p> |
| * The caret for the control is automatically hidden |
| * and shown when the control is painted or resized, |
| * when focus is gained or lost and when an the control |
| * is scrolled. To avoid drawing on top of the caret, |
| * the programmer must hide and show the caret when |
| * drawing in the window any other time. |
| * </p> |
| * @param caret the new caret for the receiver, may be null |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_INVALID_ARGUMENT - if the caret has been disposed</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public void setCaret (Caret caret) { |
| if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); |
| if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); |
| Caret newCaret = caret; |
| Caret oldCaret = this.caret; |
| this.caret = newCaret; |
| if (isFocusControl()) { |
| if (oldCaret != null) oldCaret.killFocus (); |
| if (newCaret != null) newCaret.setFocus (); |
| } |
| } |
| public boolean setFocus () { |
| if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); |
| if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); |
| if ((style & SWT.NO_FOCUS) != 0) return false; |
| return super.setFocus (); |
| } |
| int processFocusIn (int int0, int int1, int int2) { |
| int result = super.processFocusIn (int0, int1, int2); |
| if (caret != null) caret.setFocus (); |
| return result; |
| } |
| int processFocusOut(int int0, int int1, int int2) { |
| int result = super.processFocusOut (int0, int1, int2); |
| if (caret != null) caret.killFocus (); |
| return result; |
| } |
| /* |
| int processMouseDown (int callData, int arg1, int int2) { |
| if ((UtilFuncs.GTK_WIDGET_GET_FLAGS(handle) & OS.GTK_HAS_FOCUS) == 0) |
| OS.gtk_widget_grab_focus(handle); |
| GdkEventButton gdkEvent = new GdkEventButton (); |
| OS.memmove (gdkEvent, callData, GdkEventButton.sizeof); |
| int eventType = SWT.MouseDown; |
| if (gdkEvent.type == OS.GDK_2BUTTON_PRESS) eventType = SWT.MouseDoubleClick; |
| sendMouseEvent (eventType, gdkEvent.button, gdkEvent.state, gdkEvent.time, (int)gdkEvent.x, (int)gdkEvent.y); |
| if (gdkEvent.button == 3 && menu != null) { |
| menu.setVisible (true); |
| } |
| return 1; |
| } |
| |
| int processMouseUp (int callData, int arg1, int int2) { |
| GdkEventButton gdkEvent = new GdkEventButton (); |
| OS.memmove (gdkEvent, callData, GdkEventButton.sizeof); |
| sendMouseEvent (SWT.MouseUp, gdkEvent.button, gdkEvent.state, gdkEvent.time, (int)gdkEvent.x, (int)gdkEvent.y); |
| return 1; |
| } |
| */ |
| int processPaint (int callData, int arg1, int int2) { |
| //if (!hooks (SWT.Paint)) return 0; |
| |
| GdkEventExpose gdkEvent = new GdkEventExpose (); |
| OS.memmove (gdkEvent, callData, GdkEventExpose.sizeof); |
| Event event = new Event (); |
| event.count = gdkEvent.count; |
| event.x = gdkEvent.x; event.y = gdkEvent.y; |
| event.width = gdkEvent.width; event.height = gdkEvent.height; |
| GC gc = event.gc = new GC (this); |
| sendEvent (SWT.Paint, event); |
| gc.dispose (); |
| event.gc = null; |
| return 0; |
| } |
| void releaseWidget () { |
| if (caret != null) caret.releaseWidget (); |
| caret = null; |
| super.releaseWidget (); |
| } |
| |
| } |