bundles/org.eclipse.swt/Eclipse SWT/wpf/org/eclipse/swt/widgets/ExpandItem.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * 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.graphics.*;
 import org.eclipse.swt.internal.wpf.*;
 import org.eclipse.swt.*;

 /**
  * Instances of this class represent a selectable user interface object
  * that represents a expandable item in a expand bar.
  * <p>
  * <dl>
  * <dt><b>Styles:</b></dt>
  * <dd>(none)</dd>
  * <dt><b>Events:</b></dt>
  * <dd>(none)</dd>
  * </dl>
  * </p><p>
  * IMPORTANT: This class is <em>not</em> intended to be subclassed.
  * </p>
  *
  * @see ExpandBar
  * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
  *
  * @since 3.2
  * @noextend This class is not intended to be subclassed by clients.
  */
 public class ExpandItem extends Item {
 	ExpandBar parent;
 	Control control;
 	int imageHandle, textHandle, contentHandle;

 /**
  * 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 Widget#checkSubclass
  * @see Widget#getStyle
  */
 public ExpandItem (ExpandBar parent, int style) {
 	this (parent, style, checkNull (parent).getItemCount ());
 }

 /**
  * Constructs a new instance of this class given its parent, a
  * style value describing its behavior and appearance, and the index
  * at which to place it in the items maintained by its parent.
  * <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
  * @param index the zero-relative index to store the receiver in its parent
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
  *    <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the parent (inclusive)</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 Widget#checkSubclass
  * @see Widget#getStyle
  */
 public ExpandItem (ExpandBar parent, int style, int index) {
 	super (parent, style);
 	this.parent = parent;
 	parent.createItem (this, style, index);
 }

 static ExpandBar checkNull (ExpandBar control) {
 	if (control == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
 	return control;
 }

 void createHandle () {
 	handle = OS.gcnew_Expander ();
 	if (handle == 0) error (SWT.ERROR_NO_HANDLES);
 	int spacing = parent.spacing;
 	int thickness = OS.gcnew_Thickness (spacing, spacing, spacing, spacing);
 	OS.FrameworkElement_Margin (handle, thickness);
 	OS.GCHandle_Free (thickness);
 	imageHandle = OS.gcnew_Image ();
 	if (imageHandle == 0) error (SWT.ERROR_NO_HANDLES);
 	OS.Image_Stretch (imageHandle, OS.Stretch_None);
 	OS.UIElement_Visibility (imageHandle, OS.Visibility_Collapsed);
 	textHandle = OS.gcnew_TextBlock ();
 	if (textHandle == 0) error (SWT.ERROR_NO_HANDLES);
 	int panel = OS.gcnew_StackPanel ();
 	if (panel == 0) error (SWT.ERROR_NO_HANDLES);
 	OS.StackPanel_Orientation (panel, OS.Orientation_Horizontal);
 	thickness = OS.gcnew_Thickness (1, 1, 1, 1);
 	if (thickness == 0) error (SWT.ERROR_NO_HANDLES);
 	OS.FrameworkElement_Margin (panel, thickness);
 	OS.GCHandle_Free (thickness);
 	int children = OS.Panel_Children (panel);
 	OS.UIElementCollection_Add (children, imageHandle);
 	OS.UIElementCollection_Add (children, textHandle);
 	OS.GCHandle_Free (children);
 	OS.HeaderedContentControl_Header (handle, panel);
 	OS.GCHandle_Free (panel);
 	contentHandle = OS.gcnew_Canvas ();
 	if (contentHandle == 0) error (SWT.ERROR_NO_HANDLES);
 	OS.ContentControl_Content (handle, contentHandle);
 }

 void deregister () {
 	display.removeWidget (handle);
 }

 void destroyWidget () {
 	parent.destroyItem (this);
 	releaseHandle ();
 }

 /**
  * Returns the control that is shown when the item is expanded.
  * If no control has been set, return <code>null</code>.
  *
  * @return the control
  *
  * @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 Control getControl () {
 	checkWidget ();
 	return control;
 }

 /**
  * Returns <code>true</code> if the receiver is expanded,
  * and false otherwise.
  *
  * @return the expanded state
  *
  * @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 boolean getExpanded () {
 	checkWidget ();
 	return OS.Expander_IsExpanded (handle);
 }

 /**
  * Returns the height of the receiver's header
  *
  * @return the height of the header
  *
  * @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 int getHeaderHeight () {
 	checkWidget ();
 	int panel = OS.HeaderedContentControl_Header (handle);
 	return (int) OS.FrameworkElement_ActualHeight (panel);
 }

 /**
  * Gets the height of the receiver.
  *
  * @return the height
  *
  * @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 int getHeight () {
 	checkWidget ();
 	return (int) OS.FrameworkElement_Height (contentHandle);
 }

 /**
  * Returns the receiver's parent, which must be a <code>ExpandBar</code>.
  *
  * @return the receiver's parent
  *
  * @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 ExpandBar getParent () {
 	checkWidget ();
 	return parent;
 }

 Control getWidgetControl () {
 	return parent;
 }

 void HandleExpanded (int sender, int e) {
 	if (!checkEvent (e)) return;
 	Event event = new Event ();
 	event.item = this;
 	parent.notifyListeners (SWT.Expand, event);
 }

 void HandleCollapsed (int sender, int e) {
 	if (!checkEvent (e)) return;
 	Event event = new Event ();
 	event.item = this;
 	parent.notifyListeners (SWT.Collapse, event);
 }

 void HandleSizeChanged (int sender, int e) {
 	if (!checkEvent (e)) return;
 	resizeControl ();
 }

 void hookEvents () {
 	super.hookEvents ();
 	int handler = OS.gcnew_RoutedEventHandler (jniRef, "HandleExpanded");
 	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
 	OS.Expander_Expanded (handle, handler);
 	OS.GCHandle_Free (handler);
 	handler = OS.gcnew_RoutedEventHandler (jniRef, "HandleCollapsed");
 	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
 	OS.Expander_Collapsed (handle, handler);
 	OS.GCHandle_Free (handler);
 	handler = OS.gcnew_SizeChangedEventHandler (jniRef, "HandleSizeChanged");
 	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
 	OS.FrameworkElement_SizeChanged (contentHandle, handler);
 	OS.GCHandle_Free (handler);
 }

 void register () {
 	display.addWidget (handle, this);
 }

 void releaseHandle () {
 	super.releaseHandle ();
 	if (handle != 0) OS.GCHandle_Free (handle);
 	handle = 0;
 	parent = null;
 	if (textHandle != 0) OS.GCHandle_Free (textHandle);
 	textHandle = 0;
 	if (imageHandle !=0 )OS.GCHandle_Free (imageHandle);
 	imageHandle = 0;
 	if (contentHandle != 0) OS.GCHandle_Free (contentHandle);
 	contentHandle = 0;
 }

 void resizeControl () {
 	if (control != null) {
 		int width = (int) OS.FrameworkElement_ActualWidth (contentHandle);
 		int height = (int) OS.FrameworkElement_Height (contentHandle);
 		control.setSize (width, height);
 	}
 }

 /**
  * Sets the control that is shown when the item is expanded.
  *
  * @param control the new control (or null)
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_INVALID_ARGUMENT - if the control has been disposed</li>
  *    <li>ERROR_INVALID_PARENT - if the control is not in the same widget tree</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 setControl (Control control) {
 	checkWidget ();
 	if (control != null) {
 		if (control.isDisposed ()) error (SWT.ERROR_INVALID_ARGUMENT);
 		if (control.parent != parent) error (SWT.ERROR_INVALID_PARENT);
 	}
 	Control oldControl = this.control, newControl = control;
 	this.control = control;
 	int children = OS.Panel_Children (contentHandle);
 	int parentHandle = parent.parentingHandle ();
 	int parentChildren = OS.Panel_Children (parentHandle);
 	if (newControl != null) {
 		int topHandle = newControl.topHandle ();
 		OS.UIElementCollection_Remove (parentChildren, topHandle);
 		OS.UIElementCollection_Add (children, topHandle);
 	}
 	if (oldControl != null) {
 		int topHandle = oldControl.topHandle ();
 		OS.UIElementCollection_Remove (children, topHandle);
 		OS.UIElementCollection_Add (parentChildren, topHandle);
 	}
 	OS.GCHandle_Free (children);
 	OS.GCHandle_Free (parentChildren);
 }

 /**
  * Sets the expanded state of the receiver.
  *
  * @param expanded the new expanded state
  *
  * @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 setExpanded (boolean expanded) {
 	checkWidget ();
 	OS.Expander_IsExpanded(handle, expanded);
 }

 /**
  * Sets the height of the receiver. This is height of the item when it is expanded,
  * excluding the height of the header.
  *
  * @param height the new height
  *
  * @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 setHeight (int height) {
 	checkWidget ();
 	if (height < 0) return;
 	OS.FrameworkElement_Height (contentHandle, height);
 }

 public void setImage (Image image) {
 	super.setImage (image);
 	if (image != null && image.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
 	this.image = image;
 	OS.Image_Source (imageHandle, image != null ? image.handle : 0);
 	OS.UIElement_Visibility (imageHandle, image != null ? OS.Visibility_Visible : OS.Visibility_Collapsed);
 	OS.UIElement_Visibility (textHandle, image != null && text.length () == 0 ? OS.Visibility_Collapsed : OS.Visibility_Visible);
 	int spacing = image != null && text.length () != 0 ? 3 : 0;
 	int margin = OS.gcnew_Thickness (0, 0, spacing, 0);
 	if (margin == 0) error(SWT.ERROR_NO_HANDLES);
 	OS.FrameworkElement_Margin (imageHandle, margin);
 	OS.GCHandle_Free (margin);
 }

 public void setText (String string) {
 	checkWidget ();
 	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
 	if (string.equals (text)) return;
 	text = string;
 	int ptr = createDotNetString (text, false);
 	if (ptr == 0) error(SWT.ERROR_NO_HANDLES);
 	OS.TextBlock_Text (textHandle, ptr);
 	OS.GCHandle_Free (ptr);
 	OS.UIElement_Visibility (textHandle, text.length() == 0 && image != null ? OS.Visibility_Collapsed : OS.Visibility_Visible);
 	int spacing = image != null && text.length () != 0 ? 3 : 0;
 	int margin = OS.gcnew_Thickness (0, 0, spacing, 0);
 	if (margin == 0) error(SWT.ERROR_NO_HANDLES);
 	OS.FrameworkElement_Margin (imageHandle, margin);
 	OS.GCHandle_Free (margin);
 }
 }
	/*******************************************************************************
	* 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.graphics.*;
	import org.eclipse.swt.internal.wpf.*;
	import org.eclipse.swt.*;

	/**
	* Instances of this class represent a selectable user interface object
	* that represents a expandable item in a expand bar.
	* <p>
	* <dl>
	* <dt><b>Styles:</b></dt>
	* <dd>(none)</dd>
	* <dt><b>Events:</b></dt>
	* <dd>(none)</dd>
	* </dl>
	* </p><p>
	* IMPORTANT: This class is <em>not</em> intended to be subclassed.
	* </p>
	*
	* @see ExpandBar
	* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
	*
	* @since 3.2
	* @noextend This class is not intended to be subclassed by clients.
	*/
	public class ExpandItem extends Item {
	ExpandBar parent;
	Control control;
	int imageHandle, textHandle, contentHandle;

	/**
	* 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 Widget#checkSubclass
	* @see Widget#getStyle
	*/
	public ExpandItem (ExpandBar parent, int style) {
	this (parent, style, checkNull (parent).getItemCount ());
	}

	/**
	* Constructs a new instance of this class given its parent, a
	* style value describing its behavior and appearance, and the index
	* at which to place it in the items maintained by its parent.
	* <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
	* @param index the zero-relative index to store the receiver in its parent
	*
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
	* <li>ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the parent (inclusive)</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 Widget#checkSubclass
	* @see Widget#getStyle
	*/
	public ExpandItem (ExpandBar parent, int style, int index) {
	super (parent, style);
	this.parent = parent;
	parent.createItem (this, style, index);
	}

	static ExpandBar checkNull (ExpandBar control) {
	if (control == null) SWT.error (SWT.ERROR_NULL_ARGUMENT);
	return control;
	}

	void createHandle () {
	handle = OS.gcnew_Expander ();
	if (handle == 0) error (SWT.ERROR_NO_HANDLES);
	int spacing = parent.spacing;
	int thickness = OS.gcnew_Thickness (spacing, spacing, spacing, spacing);
	OS.FrameworkElement_Margin (handle, thickness);
	OS.GCHandle_Free (thickness);
	imageHandle = OS.gcnew_Image ();
	if (imageHandle == 0) error (SWT.ERROR_NO_HANDLES);
	OS.Image_Stretch (imageHandle, OS.Stretch_None);
	OS.UIElement_Visibility (imageHandle, OS.Visibility_Collapsed);
	textHandle = OS.gcnew_TextBlock ();
	if (textHandle == 0) error (SWT.ERROR_NO_HANDLES);
	int panel = OS.gcnew_StackPanel ();
	if (panel == 0) error (SWT.ERROR_NO_HANDLES);
	OS.StackPanel_Orientation (panel, OS.Orientation_Horizontal);
	thickness = OS.gcnew_Thickness (1, 1, 1, 1);
	if (thickness == 0) error (SWT.ERROR_NO_HANDLES);
	OS.FrameworkElement_Margin (panel, thickness);
	OS.GCHandle_Free (thickness);
	int children = OS.Panel_Children (panel);
	OS.UIElementCollection_Add (children, imageHandle);
	OS.UIElementCollection_Add (children, textHandle);
	OS.GCHandle_Free (children);
	OS.HeaderedContentControl_Header (handle, panel);
	OS.GCHandle_Free (panel);
	contentHandle = OS.gcnew_Canvas ();
	if (contentHandle == 0) error (SWT.ERROR_NO_HANDLES);
	OS.ContentControl_Content (handle, contentHandle);
	}

	void deregister () {
	display.removeWidget (handle);
	}

	void destroyWidget () {
	parent.destroyItem (this);
	releaseHandle ();
	}

	/**
	* Returns the control that is shown when the item is expanded.
	* If no control has been set, return <code>null</code>.
	*
	* @return the control
	*
	* @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 Control getControl () {
	checkWidget ();
	return control;
	}

	/**
	* Returns <code>true</code> if the receiver is expanded,
	* and false otherwise.
	*
	* @return the expanded state
	*
	* @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 boolean getExpanded () {
	checkWidget ();
	return OS.Expander_IsExpanded (handle);
	}

	/**
	* Returns the height of the receiver's header
	*
	* @return the height of the header
	*
	* @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 int getHeaderHeight () {
	checkWidget ();
	int panel = OS.HeaderedContentControl_Header (handle);
	return (int) OS.FrameworkElement_ActualHeight (panel);
	}

	/**
	* Gets the height of the receiver.
	*
	* @return the height
	*
	* @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 int getHeight () {
	checkWidget ();
	return (int) OS.FrameworkElement_Height (contentHandle);
	}

	/**
	* Returns the receiver's parent, which must be a <code>ExpandBar</code>.
	*
	* @return the receiver's parent
	*
	* @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 ExpandBar getParent () {
	checkWidget ();
	return parent;
	}

	Control getWidgetControl () {
	return parent;
	}

	void HandleExpanded (int sender, int e) {
	if (!checkEvent (e)) return;
	Event event = new Event ();
	event.item = this;
	parent.notifyListeners (SWT.Expand, event);
	}

	void HandleCollapsed (int sender, int e) {
	if (!checkEvent (e)) return;
	Event event = new Event ();
	event.item = this;
	parent.notifyListeners (SWT.Collapse, event);
	}

	void HandleSizeChanged (int sender, int e) {
	if (!checkEvent (e)) return;
	resizeControl ();
	}

	void hookEvents () {
	super.hookEvents ();
	int handler = OS.gcnew_RoutedEventHandler (jniRef, "HandleExpanded");
	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
	OS.Expander_Expanded (handle, handler);
	OS.GCHandle_Free (handler);
	handler = OS.gcnew_RoutedEventHandler (jniRef, "HandleCollapsed");
	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
	OS.Expander_Collapsed (handle, handler);
	OS.GCHandle_Free (handler);
	handler = OS.gcnew_SizeChangedEventHandler (jniRef, "HandleSizeChanged");
	if (handler == 0) error (SWT.ERROR_NO_HANDLES);
	OS.FrameworkElement_SizeChanged (contentHandle, handler);
	OS.GCHandle_Free (handler);
	}

	void register () {
	display.addWidget (handle, this);
	}

	void releaseHandle () {
	super.releaseHandle ();
	if (handle != 0) OS.GCHandle_Free (handle);
	handle = 0;
	parent = null;
	if (textHandle != 0) OS.GCHandle_Free (textHandle);
	textHandle = 0;
	if (imageHandle !=0 )OS.GCHandle_Free (imageHandle);
	imageHandle = 0;
	if (contentHandle != 0) OS.GCHandle_Free (contentHandle);
	contentHandle = 0;
	}

	void resizeControl () {
	if (control != null) {
	int width = (int) OS.FrameworkElement_ActualWidth (contentHandle);
	int height = (int) OS.FrameworkElement_Height (contentHandle);
	control.setSize (width, height);
	}
	}

	/**
	* Sets the control that is shown when the item is expanded.
	*
	* @param control the new control (or null)
	*
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_INVALID_ARGUMENT - if the control has been disposed</li>
	* <li>ERROR_INVALID_PARENT - if the control is not in the same widget tree</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 setControl (Control control) {
	checkWidget ();
	if (control != null) {
	if (control.isDisposed ()) error (SWT.ERROR_INVALID_ARGUMENT);
	if (control.parent != parent) error (SWT.ERROR_INVALID_PARENT);
	}
	Control oldControl = this.control, newControl = control;
	this.control = control;
	int children = OS.Panel_Children (contentHandle);
	int parentHandle = parent.parentingHandle ();
	int parentChildren = OS.Panel_Children (parentHandle);
	if (newControl != null) {
	int topHandle = newControl.topHandle ();
	OS.UIElementCollection_Remove (parentChildren, topHandle);
	OS.UIElementCollection_Add (children, topHandle);
	}
	if (oldControl != null) {
	int topHandle = oldControl.topHandle ();
	OS.UIElementCollection_Remove (children, topHandle);
	OS.UIElementCollection_Add (parentChildren, topHandle);
	}
	OS.GCHandle_Free (children);
	OS.GCHandle_Free (parentChildren);
	}

	/**
	* Sets the expanded state of the receiver.
	*
	* @param expanded the new expanded state
	*
	* @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 setExpanded (boolean expanded) {
	checkWidget ();
	OS.Expander_IsExpanded(handle, expanded);
	}

	/**
	* Sets the height of the receiver. This is height of the item when it is expanded,
	* excluding the height of the header.
	*
	* @param height the new height
	*
	* @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 setHeight (int height) {
	checkWidget ();
	if (height < 0) return;
	OS.FrameworkElement_Height (contentHandle, height);
	}

	public void setImage (Image image) {
	super.setImage (image);
	if (image != null && image.isDisposed()) error(SWT.ERROR_INVALID_ARGUMENT);
	this.image = image;
	OS.Image_Source (imageHandle, image != null ? image.handle : 0);
	OS.UIElement_Visibility (imageHandle, image != null ? OS.Visibility_Visible : OS.Visibility_Collapsed);
	OS.UIElement_Visibility (textHandle, image != null && text.length () == 0 ? OS.Visibility_Collapsed : OS.Visibility_Visible);
	int spacing = image != null && text.length () != 0 ? 3 : 0;
	int margin = OS.gcnew_Thickness (0, 0, spacing, 0);
	if (margin == 0) error(SWT.ERROR_NO_HANDLES);
	OS.FrameworkElement_Margin (imageHandle, margin);
	OS.GCHandle_Free (margin);
	}

	public void setText (String string) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	if (string.equals (text)) return;
	text = string;
	int ptr = createDotNetString (text, false);
	if (ptr == 0) error(SWT.ERROR_NO_HANDLES);
	OS.TextBlock_Text (textHandle, ptr);
	OS.GCHandle_Free (ptr);
	OS.UIElement_Visibility (textHandle, text.length() == 0 && image != null ? OS.Visibility_Collapsed : OS.Visibility_Visible);
	int spacing = image != null && text.length () != 0 ? 3 : 0;
	int margin = OS.gcnew_Thickness (0, 0, spacing, 0);
	if (margin == 0) error(SWT.ERROR_NO_HANDLES);
	OS.FrameworkElement_Margin (imageHandle, margin);
	OS.GCHandle_Free (margin);
	}
	}