| package org.eclipse.swt.widgets; |
| |
| /* |
| * Copyright (c) 2000, 2002 IBM Corp. All rights reserved. |
| * This file is made available under the terms of the Common Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/cpl-v10.html |
| */ |
| |
| import org.eclipse.swt.internal.gtk.*; |
| import org.eclipse.swt.*; |
| |
| /**
|
| * 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; |
| |
| 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
|
| * lists the style constants that are applicable to the class.
|
| * Style bits are also inherited from superclasses.
|
| * </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; |
| } |
| |
| int gtk_expose_event (int widget, int event) { |
| boolean isFocus = caret != null && caret.isFocusCaret (); |
| if (isFocus) caret.killFocus (); |
| int result = super.gtk_expose_event (widget, event); |
| if (isFocus) caret.setFocus (); |
| return result; |
| } |
| |
| int gtk_focus_in_event (int widget, int event) { |
| int result = super.gtk_focus_in_event (widget, event); |
| if (caret != null) caret.setFocus (); |
| return result; |
| } |
| |
| int gtk_focus_out_event (int widget, int event) { |
| int result = super.gtk_focus_out_event (widget, event); |
| if (caret != null) caret.killFocus (); |
| return result; |
| } |
| |
| void redrawWidget (int x, int y, int width, int height, boolean all) { |
| boolean isFocus = caret != null && caret.isFocusCaret (); |
| if (isFocus) caret.killFocus (); |
| super.redrawWidget (x, y, width, height, all); |
| if (isFocus) caret.setFocus (); |
| } |
| |
| void releaseWidget () { |
| if (caret != null) caret.releaseResources (); |
| caret = null; |
| super.releaseWidget(); |
| } |
| |
| /**
|
| * 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) { |
| checkWidget(); |
| if (width <= 0 || height <= 0) return; |
| int deltaX = destX - x, deltaY = destY - y; |
| if (deltaX == 0 && deltaY == 0) return; |
| if (!isVisible ()) return; |
| boolean isFocus = caret != null && caret.isFocusCaret (); |
| if (isFocus) caret.killFocus (); |
| |
| // update (); |
| // GC gc = new GC (this); |
| // gc.copyArea (x, y, width, height, destX, destY); |
| // gc.dispose (); |
| |
| OS.gdk_flush (); |
| while ((OS.gtk_events_pending()) != 0) { |
| OS.gtk_main_iteration (); |
| } |
| |
| int window = paintWindow (); |
| int visibleRegion = OS.gdk_drawable_get_visible_region (window); |
| GdkRectangle srcRect = new GdkRectangle (); |
| srcRect.x = x; |
| srcRect.y = y; |
| srcRect.width = width; |
| srcRect.height = height; |
| int copyRegion = OS.gdk_region_new (); |
| OS.gdk_region_union_with_rect (copyRegion, srcRect); |
| OS.gdk_region_intersect(copyRegion, visibleRegion); |
| int invalidateRegion = OS.gdk_region_new (); |
| OS.gdk_region_union_with_rect (invalidateRegion, srcRect); |
| OS.gdk_region_subtract (invalidateRegion, visibleRegion); |
| OS.gdk_region_offset (invalidateRegion, deltaX, deltaY); |
| GdkRectangle copyRect = new GdkRectangle(); |
| OS.gdk_region_get_clipbox (copyRegion, copyRect); |
| int gdkGC = OS.gdk_gc_new (window); |
| OS.gdk_gc_set_exposures (gdkGC, true); |
| OS.gdk_draw_drawable (window, gdkGC, window, copyRect.x, copyRect.y, copyRect.x + deltaX, copyRect.y + deltaY, copyRect.width, copyRect.height); |
| OS.g_object_unref (gdkGC); |
| boolean disjoint = (destX + width < x) || (x + width < destX) || (destY + height < y) || (y + height < destY); |
| GdkRectangle rect = new GdkRectangle (); |
| if (disjoint) { |
| rect.x = x; |
| rect.y = y; |
| rect.width = width; |
| rect.height = height; |
| OS.gdk_region_union_with_rect (invalidateRegion, rect); |
| } else { |
| if (deltaX != 0) { |
| int newX = destX - deltaX; |
| if (deltaX < 0) newX = destX + width; |
| rect.x = newX; |
| rect.y = y; |
| rect.width = Math.abs(deltaX); |
| rect.height = height; |
| OS.gdk_region_union_with_rect (invalidateRegion, rect); |
| } |
| if (deltaY != 0) { |
| int newY = destY - deltaY; |
| if (deltaY < 0) newY = destY + height; |
| rect.x = x; |
| rect.y = newY; |
| rect.width = width; |
| rect.height = Math.abs(deltaY); |
| OS.gdk_region_union_with_rect (invalidateRegion, rect); |
| } |
| } |
| OS.gdk_window_invalidate_region(window, invalidateRegion, all); |
| OS.gdk_region_destroy (visibleRegion); |
| OS.gdk_region_destroy (copyRegion); |
| OS.gdk_region_destroy (invalidateRegion); |
| |
| if (isFocus) caret.setFocus (); |
| } |
| |
| boolean setBounds (int x, int y, int width, int height, boolean move, boolean resize) { |
| boolean isFocus = caret != null && caret.isFocusCaret (); |
| if (isFocus) caret.killFocus (); |
| boolean changed = super.setBounds (x, y, width, height, move, resize); |
| if (isFocus) caret.setFocus (); |
| return changed; |
| } |
| |
| /**
|
| * 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) { |
| checkWidget(); |
| Caret newCaret = caret; |
| Caret oldCaret = this.caret; |
| this.caret = newCaret; |
| if (hasFocus ()) { |
| if (oldCaret != null) oldCaret.killFocus (); |
| if (newCaret != null) { |
| if (newCaret.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT); |
| newCaret.setFocus (); |
| } |
| } |
| } |
| |
| public boolean setFocus () { |
| checkWidget (); |
| if ((style & SWT.NO_FOCUS) != 0) return false; |
| return super.setFocus (); |
| } |
| |
| void updateCaret () { |
| if (imHandle == 0) return; |
| GdkRectangle rect = new GdkRectangle (); |
| rect.x = caret.x; |
| rect.y = caret.y; |
| rect.width = caret.width; |
| rect.height = caret.height; |
| OS.gtk_im_context_set_cursor_location (imHandle, rect); |
| } |
| |
| } |