| /******************************************************************************* |
| * Copyright (c) 2000, 2008 IBM Corporation and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.widgets; |
| |
| |
| import org.eclipse.swt.internal.motif.*; |
| 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 |
| * @see <a href="http://www.eclipse.org/swt/snippets/#canvas">Canvas snippets</a> |
| * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample</a> |
| * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> |
| */ |
| public class Canvas extends Composite { |
| Caret caret; |
| IME ime; |
| |
| Canvas () { |
| /* Do nothing */ |
| } |
| /** |
| * 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> |
| * </ul> |
| * |
| * @see SWT |
| * @see Widget#checkSubclass |
| * @see Widget#getStyle |
| */ |
| public Canvas (Composite parent, int style) { |
| super (parent, checkStyle (style)); |
| } |
| /** |
| * Fills the interior of the rectangle specified by the arguments, |
| * with the receiver's background. |
| * |
| * @param gc the gc where the rectangle is to be filled |
| * @param x the x coordinate of the rectangle to be filled |
| * @param y the y coordinate of the rectangle to be filled |
| * @param width the width of the rectangle to be filled |
| * @param height the height of the rectangle to be filled |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the gc is null</li> |
| * <li>ERROR_INVALID_ARGUMENT - if the gc 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> |
| * |
| * @since 3.2 |
| */ |
| public void drawBackground (GC gc, int x, int y, int width, int height) { |
| drawBackground (gc, x, y, width, height, 0 ,0); |
| } |
| /** |
| * 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 for the receiver, may be null |
| * |
| * @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; |
| } |
| /** |
| * Returns the IME. |
| * |
| * @return the IME |
| * |
| * @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> |
| * |
| * @since 3.4 |
| */ |
| public IME getIME () { |
| checkWidget (); |
| return ime; |
| } |
| Caret getIMCaret () { |
| return caret; |
| } |
| void redrawWidget (int x, int y, int width, int height, boolean redrawAll, boolean allChildren, boolean trim) { |
| boolean isFocus = caret != null && caret.isFocusCaret (); |
| if (isFocus) caret.killFocus (); |
| super.redrawWidget (x, y, width, height, redrawAll, allChildren, trim); |
| if (isFocus) caret.setFocus (); |
| } |
| |
| void releaseChildren (boolean destroy) { |
| if (caret != null) { |
| caret.release (false); |
| caret = null; |
| } |
| if (ime != null) { |
| ime.release (false); |
| ime = null; |
| } |
| super.releaseChildren (destroy); |
| } |
| |
| void reskinChildren (int flags) { |
| if (caret != null) caret.reskin (flags); |
| if (ime != null) ime.reskin (flags); |
| super.reskinChildren (flags); |
| } |
| |
| /** |
| * 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, all 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 (); |
| int xDisplay = OS.XtDisplay (handle); |
| if (xDisplay == 0) return; |
| int xWindow = OS.XtWindow (handle); |
| if (xWindow == 0) return; |
| int [] argList = {OS.XmNwidth, 0, OS.XmNheight, 0}; |
| OS.XtGetValues (handle, argList, argList.length / 2); |
| if (Math.min(x + width, argList [1]) >= Math.max (x, 0) && Math.min(y + height, 0 + argList [3]) >= Math.max (y, 0)) { |
| int xEvent = OS.XtMalloc (XEvent.sizeof); |
| OS.XSync (xDisplay, false); |
| OS.XSync (xDisplay, false); |
| while (OS.XCheckWindowEvent (xDisplay, xWindow, OS.ExposureMask, xEvent)) { |
| OS.XtDispatchEvent (xEvent); |
| } |
| OS.XtFree (xEvent); |
| } |
| Control control = findBackgroundControl (); |
| if (control == null) control = this; |
| if (control.backgroundImage != null) { |
| redrawWidget (x, y, width, height, false, false, false); |
| redrawWidget (destX, destY, width, height, false, false, false); |
| } else { |
| int xGC = OS.XCreateGC (xDisplay, xWindow, 0, null); |
| OS.XCopyArea (xDisplay, xWindow, xWindow, xGC, x, y, width, height, destX, destY); |
| OS.XFreeGC (xDisplay, xGC); |
| boolean disjoint = (destX + width < x) || (x + width < destX) || (destY + height < y) || (y + height < destY); |
| if (disjoint) { |
| OS.XClearArea (xDisplay, xWindow, x, y, width, height, true); |
| } else { |
| if (deltaX != 0) { |
| int newX = destX - deltaX; |
| if (deltaX < 0) newX = destX + width; |
| OS.XClearArea (xDisplay, xWindow, newX, y, Math.abs (deltaX), height, true); |
| } |
| if (deltaY != 0) { |
| int newY = destY - deltaY; |
| if (deltaY < 0) newY = destY + height; |
| OS.XClearArea (xDisplay, xWindow, x, newY, width, Math.abs (deltaY), true); |
| } |
| } |
| } |
| if (all) { |
| Control [] children = _getChildren (); |
| for (int i=0; i<children.length; i++) { |
| Control child = children [i]; |
| Rectangle rect = child.getBounds (); |
| if (Math.min(x + width, rect.x + rect.width) >= Math.max (x, rect.x) && |
| Math.min(y + height, rect.y + rect.height) >= Math.max (y, rect.y)) { |
| child.setLocation (rect.x + deltaX, rect.y + deltaY); |
| } |
| } |
| } |
| if (isFocus) caret.setFocus (); |
| } |
| /** |
| * 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 (); |
| } |
| } |
| } |
| 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; |
| } |
| public void setFont (Font font) { |
| checkWidget(); |
| if (caret != null) caret.setFont (font); |
| super.setFont (font); |
| } |
| /** |
| * Sets the receiver's IME. |
| * |
| * @param ime the new IME for the receiver, may be null |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_INVALID_ARGUMENT - if the IME 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> |
| * |
| * @since 3.4 |
| */ |
| public void setIME (IME ime) { |
| checkWidget (); |
| if (ime != null && ime.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT); |
| this.ime = ime; |
| } |
| int XExposure (int w, int client_data, int call_data, int continue_to_dispatch) { |
| boolean isFocus = caret != null && caret.isFocusCaret (); |
| if (isFocus) caret.killFocus (); |
| int result = super.XExposure (w, client_data, call_data, continue_to_dispatch); |
| if (isFocus) caret.setFocus (); |
| return result; |
| } |
| int xFocusIn (XFocusChangeEvent xEvent) { |
| int result = super.xFocusIn (xEvent); |
| if (caret != null) caret.setFocus (); |
| return result; |
| } |
| int xFocusOut (XFocusChangeEvent xEvent) { |
| int result = super.xFocusOut (xEvent); |
| if (caret != null) caret.killFocus (); |
| return result; |
| } |
| } |