| 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.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
|
| */ |
| public class Canvas extends Composite {
|
| Caret caret;
|
|
|
| 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> |
| * <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;
|
| }
|
|
|
| short [] getIMECaretPos () {
|
| if (caret == null) return super.getIMECaretPos ();
|
| int width = caret.width;
|
| if (width <= 0) width = 2;
|
| return new short[]{(short) (caret.x + width), (short) (caret.y + caret.height)};
|
| }
|
| int processFocusIn () {
|
| int result = super.processFocusIn ();
|
| if (caret != null) caret.setFocus ();
|
| return result;
|
| }
|
| int processFocusOut () {
|
| int result = super.processFocusOut ();
|
| if (caret != null) caret.killFocus ();
|
| return result;
|
| }
|
|
|
| int processPaint (int callData) {
|
| boolean isFocus = caret != null && caret.isFocusCaret ();
|
| if (isFocus) caret.killFocus ();
|
| int result = super.processPaint (callData);
|
| if (isFocus) caret.setFocus ();
|
| 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.releaseWidget ();
|
| caret.releaseHandle ();
|
| }
|
| 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;
|
|
|
| /* Hide the caret */
|
| boolean isFocus = caret != null && caret.isFocusCaret ();
|
| if (isFocus) caret.killFocus ();
|
|
|
| /* Flush outstanding exposes */
|
| int xDisplay = OS.XtDisplay (handle);
|
| if (xDisplay == 0) return;
|
| int xWindow = OS.XtWindow (handle);
|
| if (xWindow == 0) return;
|
| XAnyEvent xEvent = new XAnyEvent ();
|
| OS.XSync (xDisplay, false); OS.XSync (xDisplay, false);
|
| while (OS.XCheckWindowEvent (xDisplay, xWindow, OS.ExposureMask, xEvent)) {
|
| OS.XtDispatchEvent (xEvent);
|
| }
|
|
|
| /* Scroll the window */
|
| 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);
|
| }
|
| }
|
|
|
| /* Show the caret */
|
| 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;
|
| }
|
| void updateCaret () {
|
| if (caret == null) return;
|
| if (!IsDBLocale) return;
|
| short [] point = getIMECaretPos ();
|
| int ptr = OS.XtMalloc (4);
|
| OS.memmove (ptr, point, 4);
|
| int[] argList = {OS.XmNspotLocation, ptr};
|
| OS.XmImSetValues (handle, argList, argList.length / 2);
|
| if (ptr != 0) OS.XtFree (ptr);
|
| }
|
| }
|