bundles/org.eclipse.swt/Eclipse SWT/win32/org/eclipse/swt/widgets/Canvas.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2005 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.win32.*;
 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;

 /**
  * Prevents uninitialized instances from being created outside the package.
  */
 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>
  * </ul>
  *
  * @see SWT
  * @see Widget#checkSubclass
  * @see Widget#getStyle
  */
 public Canvas (Composite parent, int style) {
 	super (parent, style);
 }

 /*
 * Not currently used.
 */
 void clearArea (int x, int y, int width, int height) {
 	checkWidget ();
 	if (OS.IsWindowVisible (handle)) return;
 	RECT rect = new RECT ();
 	OS.SetRect (rect, x, y, x + width, y + height);
 	int hDC = OS.GetDCEx (handle, 0, OS.DCX_CACHE | OS.DCX_CLIPCHILDREN | OS.DCX_CLIPSIBLINGS);
 	drawBackground (hDC, rect);
 	OS.ReleaseDC (handle, hDC);
 }

 /**
  * 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;
 }

 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 ();
 	forceResize ();
 	boolean isFocus = caret != null && caret.isFocusCaret ();
 	if (isFocus) caret.killFocus ();
 	RECT sourceRect = new RECT ();
 	OS.SetRect (sourceRect, x, y, x + width, y + height);
 	RECT clientRect = new RECT ();
 	OS.GetClientRect (handle, clientRect);
 	if (OS.IntersectRect (clientRect, sourceRect, clientRect)) {
 		if (OS.IsWinCE) {
 			OS.UpdateWindow (handle);
 		} else {
 			int flags = OS.RDW_UPDATENOW | OS.RDW_ALLCHILDREN;
 			OS.RedrawWindow (handle, null, 0, flags);
 		}
 	}
 	int deltaX = destX - x, deltaY = destY - y;
 	int flags = OS.SW_INVALIDATE | OS.SW_ERASE;
 	/*
 	* Feature in Windows.  If any child in the widget tree partially
 	* intersects the scrolling rectangle, Windows moves the child
 	* and copies the bits that intersect the scrolling rectangle but
 	* does not redraw the child.
 	*
 	* Feature in Windows.  When any child in the widget tree does not
 	* intersect the scrolling rectangle but the parent does intersect,
 	* Windows does not move the child.  This is the documented (but
 	* strange) Windows behavior.
 	*
 	* The fix is to not use SW_SCROLLCHILDREN and move the children
 	* explicitly after scrolling.
 	*/
 //	if (all) flags |= OS.SW_SCROLLCHILDREN;
 	OS.ScrollWindowEx (handle, deltaX, deltaY, sourceRect, null, 0, null, flags);
 	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 (isFocusControl ()) {
 		if (oldCaret != null) oldCaret.killFocus ();
 		if (newCaret != null) {
 			if (newCaret.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
 			newCaret.setFocus ();
 		}
 	}
 }

 public void setFont (Font font) {
 	checkWidget ();
 	if (caret != null) caret.setFont (font);
 	super.setFont (font);
 }

 LRESULT WM_INPUTLANGCHANGE (int wParam, int lParam) {
 	LRESULT result  = super.WM_INPUTLANGCHANGE (wParam, lParam);
 	if (caret != null && caret.isFocusCaret ()) {
 		caret.setIMEFont ();
 		caret.resizeIME ();
 	}
 	return result;
 }

 LRESULT WM_KILLFOCUS (int wParam, int lParam) {
 	LRESULT result  = super.WM_KILLFOCUS (wParam, lParam);
 	if (caret != null) caret.killFocus ();
 	return result;
 }

 LRESULT WM_SETFOCUS (int wParam, int lParam) {
 	LRESULT result  = super.WM_SETFOCUS (wParam, lParam);
 	if (caret != null) caret.setFocus ();
 	return result;
 }

 LRESULT WM_SIZE (int wParam, int lParam) {
 	LRESULT result  = super.WM_SIZE (wParam, lParam);
 	if (caret != null && caret.isFocusCaret ()) caret.resizeIME ();
 	return result;
 }

 LRESULT WM_WINDOWPOSCHANGED (int wParam, int lParam) {
 	LRESULT result  = super.WM_WINDOWPOSCHANGED (wParam, lParam);
 	if (result != null) return result;
 	/*
 	* Bug in Windows.  When a window with style WS_EX_LAYOUTRTL
 	* that contains a caret is resized, Windows does not move the
 	* caret in relation to the mirrored origin in the top right.
 	* The fix is to hide the caret in WM_WINDOWPOSCHANGING and
 	* show the caret in WM_WINDOWPOSCHANGED.
 	*/
 	boolean isFocus = (style & SWT.RIGHT_TO_LEFT) != 0 && caret != null && caret.isFocusCaret ();
 	if (isFocus) caret.setFocus ();
 	return result;
 }

 LRESULT WM_WINDOWPOSCHANGING (int wParam, int lParam) {
 	LRESULT result  = super.WM_WINDOWPOSCHANGING (wParam, lParam);
 	if (result != null) return result;
 	/*
 	* Bug in Windows.  When a window with style WS_EX_LAYOUTRTL
 	* that contains a caret is resized, Windows does not move the
 	* caret in relation to the mirrored origin in the top right.
 	* The fix is to hide the caret in WM_WINDOWPOSCHANGING and
 	* show the caret in WM_WINDOWPOSCHANGED.
 	*/
 	boolean isFocus = (style & SWT.RIGHT_TO_LEFT) != 0 && caret != null && caret.isFocusCaret ();
 	if (isFocus) caret.killFocus ();
 	return result;
 }

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2005 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.win32.*;
	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;

	/**
	* Prevents uninitialized instances from being created outside the package.
	*/
	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>
	* </ul>
	*
	* @see SWT
	* @see Widget#checkSubclass
	* @see Widget#getStyle
	*/
	public Canvas (Composite parent, int style) {
	super (parent, style);
	}

	/*
	* Not currently used.
	*/
	void clearArea (int x, int y, int width, int height) {
	checkWidget ();
	if (OS.IsWindowVisible (handle)) return;
	RECT rect = new RECT ();
	OS.SetRect (rect, x, y, x + width, y + height);
	int hDC = OS.GetDCEx (handle, 0, OS.DCX_CACHE \| OS.DCX_CLIPCHILDREN \| OS.DCX_CLIPSIBLINGS);
	drawBackground (hDC, rect);
	OS.ReleaseDC (handle, hDC);
	}

	/**
	* 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;
	}

	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 ();
	forceResize ();
	boolean isFocus = caret != null && caret.isFocusCaret ();
	if (isFocus) caret.killFocus ();
	RECT sourceRect = new RECT ();
	OS.SetRect (sourceRect, x, y, x + width, y + height);
	RECT clientRect = new RECT ();
	OS.GetClientRect (handle, clientRect);
	if (OS.IntersectRect (clientRect, sourceRect, clientRect)) {
	if (OS.IsWinCE) {
	OS.UpdateWindow (handle);
	} else {
	int flags = OS.RDW_UPDATENOW \| OS.RDW_ALLCHILDREN;
	OS.RedrawWindow (handle, null, 0, flags);
	}
	}
	int deltaX = destX - x, deltaY = destY - y;
	int flags = OS.SW_INVALIDATE \| OS.SW_ERASE;
	/*
	* Feature in Windows. If any child in the widget tree partially
	* intersects the scrolling rectangle, Windows moves the child
	* and copies the bits that intersect the scrolling rectangle but
	* does not redraw the child.
	*
	* Feature in Windows. When any child in the widget tree does not
	* intersect the scrolling rectangle but the parent does intersect,
	* Windows does not move the child. This is the documented (but
	* strange) Windows behavior.
	*
	* The fix is to not use SW_SCROLLCHILDREN and move the children
	* explicitly after scrolling.
	*/
	// if (all) flags \|= OS.SW_SCROLLCHILDREN;
	OS.ScrollWindowEx (handle, deltaX, deltaY, sourceRect, null, 0, null, flags);
	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 (isFocusControl ()) {
	if (oldCaret != null) oldCaret.killFocus ();
	if (newCaret != null) {
	if (newCaret.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
	newCaret.setFocus ();
	}
	}
	}

	public void setFont (Font font) {
	checkWidget ();
	if (caret != null) caret.setFont (font);
	super.setFont (font);
	}

	LRESULT WM_INPUTLANGCHANGE (int wParam, int lParam) {
	LRESULT result = super.WM_INPUTLANGCHANGE (wParam, lParam);
	if (caret != null && caret.isFocusCaret ()) {
	caret.setIMEFont ();
	caret.resizeIME ();
	}
	return result;
	}

	LRESULT WM_KILLFOCUS (int wParam, int lParam) {
	LRESULT result = super.WM_KILLFOCUS (wParam, lParam);
	if (caret != null) caret.killFocus ();
	return result;
	}

	LRESULT WM_SETFOCUS (int wParam, int lParam) {
	LRESULT result = super.WM_SETFOCUS (wParam, lParam);
	if (caret != null) caret.setFocus ();
	return result;
	}

	LRESULT WM_SIZE (int wParam, int lParam) {
	LRESULT result = super.WM_SIZE (wParam, lParam);
	if (caret != null && caret.isFocusCaret ()) caret.resizeIME ();
	return result;
	}

	LRESULT WM_WINDOWPOSCHANGED (int wParam, int lParam) {
	LRESULT result = super.WM_WINDOWPOSCHANGED (wParam, lParam);
	if (result != null) return result;
	/*
	* Bug in Windows. When a window with style WS_EX_LAYOUTRTL
	* that contains a caret is resized, Windows does not move the
	* caret in relation to the mirrored origin in the top right.
	* The fix is to hide the caret in WM_WINDOWPOSCHANGING and
	* show the caret in WM_WINDOWPOSCHANGED.
	*/
	boolean isFocus = (style & SWT.RIGHT_TO_LEFT) != 0 && caret != null && caret.isFocusCaret ();
	if (isFocus) caret.setFocus ();
	return result;
	}

	LRESULT WM_WINDOWPOSCHANGING (int wParam, int lParam) {
	LRESULT result = super.WM_WINDOWPOSCHANGING (wParam, lParam);
	if (result != null) return result;
	/*
	* Bug in Windows. When a window with style WS_EX_LAYOUTRTL
	* that contains a caret is resized, Windows does not move the
	* caret in relation to the mirrored origin in the top right.
	* The fix is to hide the caret in WM_WINDOWPOSCHANGING and
	* show the caret in WM_WINDOWPOSCHANGED.
	*/
	boolean isFocus = (style & SWT.RIGHT_TO_LEFT) != 0 && caret != null && caret.isFocusCaret ();
	if (isFocus) caret.killFocus ();
	return result;
	}

	}