bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/TabItem.java - platform/eclipse.platform.swt - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2016 IBM Corporation and others.
  *
  * This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License 2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * SPDX-License-Identifier: EPL-2.0
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.swt.widgets;


 import org.eclipse.swt.*;
 import org.eclipse.swt.graphics.*;
 import org.eclipse.swt.internal.*;
 import org.eclipse.swt.internal.gtk.*;

 /**
  * Instances of this class represent a selectable user interface object
  * corresponding to a tab for a page in a tab folder.
  * <dl>
  * <dt><b>Styles:</b></dt>
  * <dd>(none)</dd>
  * <dt><b>Events:</b></dt>
  * <dd>(none)</dd>
  * </dl>
  * <p>
  * IMPORTANT: This class is <em>not</em> intended to be subclassed.
  * </p>
  *
  * @see <a href="http://www.eclipse.org/swt/snippets/#tabfolder">TabFolder, TabItem snippets</a>
  * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
  * @noextend This class is not intended to be subclassed by clients.
  */
 public class TabItem extends Item {
 	long labelHandle, imageHandle, pageHandle, provider;
 	Control control;
 	TabFolder parent;
 	String toolTipText;

 /**
  * Constructs a new instance of this class given its parent
  * (which must be a <code>TabFolder</code>) and a style value
  * describing its behavior and appearance. The item is added
  * to the end of 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
  *
  * @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 TabItem (TabFolder parent, int style) {
 	super (parent, style);
 	this.parent = parent;
 	createWidget (parent.getItemCount ());
 }

 /**
  * Constructs a new instance of this class given its parent
  * (which must be a <code>TabFolder</code>), 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 SWT
  * @see Widget#checkSubclass
  * @see Widget#getStyle
  */
 public TabItem (TabFolder parent, int style, int index) {
 	super (parent, style);
 	this.parent = parent;
 	createWidget (index);
 }

 @Override
 protected void checkSubclass () {
 	if (!isValidSubclass ()) error (SWT.ERROR_INVALID_SUBCLASS);
 }

 @Override
 void createWidget (int index) {
 	parent.createItem (this, index);
 	setOrientation (true);
 	hookEvents ();
 	register ();
 	text = "";
 }

 @Override
 void deregister() {
 	super.deregister ();
 	if (labelHandle != 0) display.removeWidget (labelHandle);
 }

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

 /**
  * Returns a rectangle describing the receiver's size and location
  * relative to its parent.
  *
  * @return the receiver's bounding rectangle
  *
  * @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 Rectangle getBounds () {
 	checkWidget ();
 	return DPIUtil.autoScaleDown (getBoundsInPixels ());
 }

 Rectangle getBoundsInPixels () {
 	checkWidget();
 	GtkAllocation allocation = new GtkAllocation ();
 	GTK.gtk_widget_get_allocation (handle, allocation);
 	int x = allocation.x;
 	int y = allocation.y;
 	int width = (state & ZERO_WIDTH) != 0 ? 0 : allocation.width;
 	int height = (state & ZERO_HEIGHT) != 0 ? 0 : allocation.height;
 	if ((parent.style & SWT.MIRRORED) != 0) x = parent.getClientWidth () - width - x;
 	return new Rectangle (x, y, width, height);
 }

 /**
  * Returns the control that is used to fill the client area of
  * the tab folder when the user selects the tab item.  If no
  * control has been set, return <code>null</code>.
  * <p>
  * @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 the receiver's parent, which must be a <code>TabFolder</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 TabFolder getParent () {
 	checkWidget ();
 	return parent;
 }

 /**
  * Returns the receiver's tool tip text, or null if it has
  * not been set.
  *
  * @return the receiver's tool tip text
  *
  * @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 String getToolTipText () {
 	checkWidget ();
 	return toolTipText;
 }

 @Override
 long gtk_enter_notify_event (long widget, long event) {
 	parent.gtk_enter_notify_event (widget, event);
 	return 0;
 }

 @Override
 long gtk_mnemonic_activate (long widget, long arg1) {
 	return parent.gtk_mnemonic_activate (widget, arg1);
 }

 @Override
 void hookEvents () {
 	super.hookEvents ();
 	if (labelHandle != 0) OS.g_signal_connect_closure_by_id (labelHandle, display.signalIds [MNEMONIC_ACTIVATE], 0, display.getClosure (MNEMONIC_ACTIVATE), false);
 	if (GTK.GTK4) {
 		long motionController = GTK.gtk_event_controller_motion_new();
 		GTK.gtk_widget_add_controller(handle, motionController);
 		GTK.gtk_event_controller_set_propagation_phase(motionController, GTK.GTK_PHASE_TARGET);

 		long enterMotionAddress = display.enterMotionScrollCallback.getAddress();
 		OS.g_signal_connect (motionController, OS.enter, enterMotionAddress, ENTER);
 	} else {
 		OS.g_signal_connect_closure_by_id (handle, display.signalIds [ENTER_NOTIFY_EVENT], 0, display.getClosure (ENTER_NOTIFY_EVENT), false);
 	}
 }

 @Override
 void register () {
 	super.register ();
 	if (labelHandle != 0) display.addWidget (labelHandle, this);
 }


 @Override
 void release (boolean destroy) {
 	//Since controls are now nested under the tabItem,
 	//tabItem is responsible for it's release.
 	if (control != null && !control.isDisposed ()) {
 		Control.gtk_widget_reparent (control, parent.parentingHandle());
 	}
 	super.release (destroy);
 }

 @Override
 void releaseHandle () {
 	super.releaseHandle ();
 	pageHandle = labelHandle = imageHandle = 0;
 	parent = null;
 }

 @Override
 void releaseParent () {
 	super.releaseParent ();
 	int index = parent.indexOf (this);
 	if (index == parent.getSelectionIndex ()) {
 		if (control != null) control.setVisible (false);
 	}
 }

 /**
  * Sets the control that is used to fill the client area of
  * the tab folder when the user selects the tab item.
  * <p>
  * @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);
 	}

 	if (control != null) {
 		// To understand why we reparent, see implementation note about bug 454936 at the start of TabFolder.
 		if (GTK.GTK4) {
 			long widget = control.topHandle();
 			long parentContainer = GTK.gtk_widget_get_parent (widget);
 			if (parentContainer != 0) {
 				OS.g_object_ref (widget); //so that it won't get destroyed due to lack of references.
 				OS.swt_fixed_remove (parentContainer, widget);
 				OS.swt_fixed_add (pageHandle, widget);
 				OS.g_object_unref (widget);
 				GTK.gtk_widget_show(widget);
 			}
 		} else {
 			Control.gtk_widget_reparent (control, pageHandle);
 		}
 	}

 	Control oldControl = this.control, newControl = control;
 	this.control = control;
 	int index = parent.indexOf (this), selectionIndex = parent.getSelectionIndex();
 	if (index != selectionIndex) {
 		if (newControl != null) {
 			if (selectionIndex != -1) {
 				Control selectedControl = parent.getItem(selectionIndex).getControl();
 				if (selectedControl == newControl) return;
 			}
 			newControl.setVisible(false);
 			return;
 		}
 	}
 	if (newControl != null) {
 		newControl.setBoundsInPixels (parent.getClientAreaInPixels ());
 		newControl.setVisible (true);
 	}

 	if ((oldControl != null) && (oldControl != newControl)) {
 		Control.gtk_widget_reparent (oldControl, parent.parentingHandle());
 		if (newControl != null) {
 			oldControl.setVisible (false);
 		}
 	}
 }

 void setFontDescription (long font) {
 	setFontDescription (labelHandle, font);
 	setFontDescription (imageHandle, font);
 }

 void setForegroundRGBA (GdkRGBA rgba) {
 	setForegroundGdkRGBA (labelHandle, rgba);
 	setForegroundGdkRGBA (imageHandle, rgba);
 }

 void setForegroundGdkRGBA (long handle, GdkRGBA rgba) {
 	GdkRGBA toSet = new GdkRGBA();
 	if (rgba != null) {
 		toSet = rgba;
 	} else {
 		toSet = display.COLOR_WIDGET_FOREGROUND_RGBA;
 	}
 	long context = GTK.gtk_widget_get_style_context (handle);
 	// Form foreground string
 	String color = display.gtk_rgba_to_css_string(toSet);
 	String css = "* {color: " + color + ";}";

 	// Cache and apply foreground color
 	parent.cssForeground = css;
 	gtk_css_provider_load_from_css(context, css);
 }

 void gtk_css_provider_load_from_css (long context, String css) {
 	/* Utility function. */
 	//@param css : a 'css java' string like "{\nbackground: red;\n}".
 	if (provider == 0) {
 		provider = GTK.gtk_css_provider_new ();
 		GTK.gtk_style_context_add_provider (context, provider, GTK.GTK_STYLE_PROVIDER_PRIORITY_APPLICATION);
 		OS.g_object_unref (provider);
 	}
 	if (GTK.GTK4) {
 		GTK.gtk_css_provider_load_from_data (provider, Converter.wcsToMbcs (css, true), -1);
 	} else {
 		GTK.gtk_css_provider_load_from_data (provider, Converter.wcsToMbcs (css, true), -1, null);
 	}
 }

 @Override
 public void setImage (Image image) {
 	checkWidget ();
 	super.setImage (image);
 	if (image != null) {
 		ImageList imageList = parent.imageList;
 		if (imageList == null) imageList = parent.imageList = new ImageList ();
 		int imageIndex = imageList.indexOf (image);
 		if (imageIndex == -1) {
 			imageIndex = imageList.add (image);
 		} else {
 			imageList.put (imageIndex, image);
 		}

 		if (GTK.GTK4) {
 			GTK.gtk_image_set_from_pixbuf(imageHandle, imageList.getPixbuf(imageIndex));
 		} else {
 			GTK.gtk_image_set_from_surface(imageHandle, image.surface);
 		}
 		GTK.gtk_widget_show(imageHandle);
 	} else {
 		if (GTK.GTK4) {
 			GTK.gtk_image_clear(imageHandle);
 		} else {
 			GTK.gtk_image_set_from_surface(imageHandle, 0);
 		}
 		GTK.gtk_widget_hide(imageHandle);
 	}
 }

 @Override
 void setOrientation (boolean create) {
 	if ((parent.style & SWT.RIGHT_TO_LEFT) != 0 || !create) {
 		int dir = (parent.style & SWT.RIGHT_TO_LEFT) != 0 ? GTK.GTK_TEXT_DIR_RTL : GTK.GTK_TEXT_DIR_LTR;
 		if (handle != 0) GTK.gtk_widget_set_direction (handle, dir);
 		if (labelHandle != 0) GTK.gtk_widget_set_direction (labelHandle, dir);
 		if (imageHandle != 0) GTK.gtk_widget_set_direction (imageHandle, dir);
 		if (pageHandle != 0) GTK.gtk_widget_set_direction (pageHandle, dir);
 	}
 }

 /**
  * Sets the receiver's text.  The string may include
  * the mnemonic character.
  * <p>
  * Mnemonics are indicated by an '&amp;' that causes the next
  * character to be the mnemonic.  When the user presses a
  * key sequence that matches the mnemonic, a selection
  * event occurs. On most platforms, the mnemonic appears
  * underlined but may be emphasised in a platform specific
  * manner.  The mnemonic indicator character '&amp;' can be
  * escaped by doubling it in the string, causing a single
  * '&amp;' to be displayed.
  * </p>
  *
  * @param string the new text
  *
  * @exception IllegalArgumentException <ul>
  *    <li>ERROR_NULL_ARGUMENT - if the text is null</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>
  *
  */
 @Override
 public void setText (String string) {
 	checkWidget ();
 	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
 	super.setText (string);
 	char [] chars = fixMnemonic (string);
 	byte [] buffer = Converter.wcsToMbcs (chars, true);
 	GTK.gtk_label_set_text_with_mnemonic (labelHandle, buffer);
 	if (string.length () != 0) {
 		GTK.gtk_widget_show (labelHandle);
 	} else {
 		GTK.gtk_widget_hide (labelHandle);
 	}
 }

 /**
  * Sets the receiver's tool tip text to the argument, which
  * may be null indicating that the default tool tip for the
  * control will be shown. For a control that has a default
  * tool tip, such as the Tree control on Windows, setting
  * the tool tip text to an empty string replaces the default,
  * causing no tool tip text to be shown.
  * <p>
  * The mnemonic indicator (character '&amp;') is not displayed in a tool tip.
  * To display a single '&amp;' in the tool tip, the character '&amp;' can be
  * escaped by doubling it in the string.
  * </p>
  * <p>
  * NOTE: This operation is a hint and behavior is platform specific, on Windows
  * for CJK-style mnemonics of the form " (&amp;C)" at the end of the tooltip text
  * are not shown in tooltip.
  * </p>
  *
  * @param string the new tool tip text (or 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 void setToolTipText (String string) {
 	checkWidget ();
 	Shell shell = parent._getShell ();
 	shell.setToolTipText (handle, string);
 	toolTipText = string;
 }

 @Override
 long dpiChanged(long object, long arg0) {
 	super.dpiChanged(object, arg0);

 	if (image != null) {
 		image.internal_gtk_refreshImageForZoom();
 		setImage(image);
 	}

 	return 0;
 }
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2016 IBM Corporation and others.
	*
	* This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License 2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* SPDX-License-Identifier: EPL-2.0
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/
	package org.eclipse.swt.widgets;


	import org.eclipse.swt.*;
	import org.eclipse.swt.graphics.*;
	import org.eclipse.swt.internal.*;
	import org.eclipse.swt.internal.gtk.*;

	/**
	* Instances of this class represent a selectable user interface object
	* corresponding to a tab for a page in a tab folder.
	* <dl>
	* <dt><b>Styles:</b></dt>
	* <dd>(none)</dd>
	* <dt><b>Events:</b></dt>
	* <dd>(none)</dd>
	* </dl>
	* <p>
	* IMPORTANT: This class is <em>not</em> intended to be subclassed.
	* </p>
	*
	* @see <a href="http://www.eclipse.org/swt/snippets/#tabfolder">TabFolder, TabItem snippets</a>
	* @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
	* @noextend This class is not intended to be subclassed by clients.
	*/
	public class TabItem extends Item {
	long labelHandle, imageHandle, pageHandle, provider;
	Control control;
	TabFolder parent;
	String toolTipText;

	/**
	* Constructs a new instance of this class given its parent
	* (which must be a <code>TabFolder</code>) and a style value
	* describing its behavior and appearance. The item is added
	* to the end of 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
	*
	* @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 TabItem (TabFolder parent, int style) {
	super (parent, style);
	this.parent = parent;
	createWidget (parent.getItemCount ());
	}

	/**
	* Constructs a new instance of this class given its parent
	* (which must be a <code>TabFolder</code>), 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 SWT
	* @see Widget#checkSubclass
	* @see Widget#getStyle
	*/
	public TabItem (TabFolder parent, int style, int index) {
	super (parent, style);
	this.parent = parent;
	createWidget (index);
	}

	@Override
	protected void checkSubclass () {
	if (!isValidSubclass ()) error (SWT.ERROR_INVALID_SUBCLASS);
	}

	@Override
	void createWidget (int index) {
	parent.createItem (this, index);
	setOrientation (true);
	hookEvents ();
	register ();
	text = "";
	}

	@Override
	void deregister() {
	super.deregister ();
	if (labelHandle != 0) display.removeWidget (labelHandle);
	}

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

	/**
	* Returns a rectangle describing the receiver's size and location
	* relative to its parent.
	*
	* @return the receiver's bounding rectangle
	*
	* @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 Rectangle getBounds () {
	checkWidget ();
	return DPIUtil.autoScaleDown (getBoundsInPixels ());
	}

	Rectangle getBoundsInPixels () {
	checkWidget();
	GtkAllocation allocation = new GtkAllocation ();
	GTK.gtk_widget_get_allocation (handle, allocation);
	int x = allocation.x;
	int y = allocation.y;
	int width = (state & ZERO_WIDTH) != 0 ? 0 : allocation.width;
	int height = (state & ZERO_HEIGHT) != 0 ? 0 : allocation.height;
	if ((parent.style & SWT.MIRRORED) != 0) x = parent.getClientWidth () - width - x;
	return new Rectangle (x, y, width, height);
	}

	/**
	* Returns the control that is used to fill the client area of
	* the tab folder when the user selects the tab item. If no
	* control has been set, return <code>null</code>.
	* <p>
	* @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 the receiver's parent, which must be a <code>TabFolder</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 TabFolder getParent () {
	checkWidget ();
	return parent;
	}

	/**
	* Returns the receiver's tool tip text, or null if it has
	* not been set.
	*
	* @return the receiver's tool tip text
	*
	* @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 String getToolTipText () {
	checkWidget ();
	return toolTipText;
	}

	@Override
	long gtk_enter_notify_event (long widget, long event) {
	parent.gtk_enter_notify_event (widget, event);
	return 0;
	}

	@Override
	long gtk_mnemonic_activate (long widget, long arg1) {
	return parent.gtk_mnemonic_activate (widget, arg1);
	}

	@Override
	void hookEvents () {
	super.hookEvents ();
	if (labelHandle != 0) OS.g_signal_connect_closure_by_id (labelHandle, display.signalIds [MNEMONIC_ACTIVATE], 0, display.getClosure (MNEMONIC_ACTIVATE), false);
	if (GTK.GTK4) {
	long motionController = GTK.gtk_event_controller_motion_new();
	GTK.gtk_widget_add_controller(handle, motionController);
	GTK.gtk_event_controller_set_propagation_phase(motionController, GTK.GTK_PHASE_TARGET);

	long enterMotionAddress = display.enterMotionScrollCallback.getAddress();
	OS.g_signal_connect (motionController, OS.enter, enterMotionAddress, ENTER);
	} else {
	OS.g_signal_connect_closure_by_id (handle, display.signalIds [ENTER_NOTIFY_EVENT], 0, display.getClosure (ENTER_NOTIFY_EVENT), false);
	}
	}

	@Override
	void register () {
	super.register ();
	if (labelHandle != 0) display.addWidget (labelHandle, this);
	}


	@Override
	void release (boolean destroy) {
	//Since controls are now nested under the tabItem,
	//tabItem is responsible for it's release.
	if (control != null && !control.isDisposed ()) {
	Control.gtk_widget_reparent (control, parent.parentingHandle());
	}
	super.release (destroy);
	}

	@Override
	void releaseHandle () {
	super.releaseHandle ();
	pageHandle = labelHandle = imageHandle = 0;
	parent = null;
	}

	@Override
	void releaseParent () {
	super.releaseParent ();
	int index = parent.indexOf (this);
	if (index == parent.getSelectionIndex ()) {
	if (control != null) control.setVisible (false);
	}
	}

	/**
	* Sets the control that is used to fill the client area of
	* the tab folder when the user selects the tab item.
	* <p>
	* @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);
	}

	if (control != null) {
	// To understand why we reparent, see implementation note about bug 454936 at the start of TabFolder.
	if (GTK.GTK4) {
	long widget = control.topHandle();
	long parentContainer = GTK.gtk_widget_get_parent (widget);
	if (parentContainer != 0) {
	OS.g_object_ref (widget); //so that it won't get destroyed due to lack of references.
	OS.swt_fixed_remove (parentContainer, widget);
	OS.swt_fixed_add (pageHandle, widget);
	OS.g_object_unref (widget);
	GTK.gtk_widget_show(widget);
	}
	} else {
	Control.gtk_widget_reparent (control, pageHandle);
	}
	}

	Control oldControl = this.control, newControl = control;
	this.control = control;
	int index = parent.indexOf (this), selectionIndex = parent.getSelectionIndex();
	if (index != selectionIndex) {
	if (newControl != null) {
	if (selectionIndex != -1) {
	Control selectedControl = parent.getItem(selectionIndex).getControl();
	if (selectedControl == newControl) return;
	}
	newControl.setVisible(false);
	return;
	}
	}
	if (newControl != null) {
	newControl.setBoundsInPixels (parent.getClientAreaInPixels ());
	newControl.setVisible (true);
	}

	if ((oldControl != null) && (oldControl != newControl)) {
	Control.gtk_widget_reparent (oldControl, parent.parentingHandle());
	if (newControl != null) {
	oldControl.setVisible (false);
	}
	}
	}

	void setFontDescription (long font) {
	setFontDescription (labelHandle, font);
	setFontDescription (imageHandle, font);
	}

	void setForegroundRGBA (GdkRGBA rgba) {
	setForegroundGdkRGBA (labelHandle, rgba);
	setForegroundGdkRGBA (imageHandle, rgba);
	}

	void setForegroundGdkRGBA (long handle, GdkRGBA rgba) {
	GdkRGBA toSet = new GdkRGBA();
	if (rgba != null) {
	toSet = rgba;
	} else {
	toSet = display.COLOR_WIDGET_FOREGROUND_RGBA;
	}
	long context = GTK.gtk_widget_get_style_context (handle);
	// Form foreground string
	String color = display.gtk_rgba_to_css_string(toSet);
	String css = "* {color: " + color + ";}";

	// Cache and apply foreground color
	parent.cssForeground = css;
	gtk_css_provider_load_from_css(context, css);
	}

	void gtk_css_provider_load_from_css (long context, String css) {
	/* Utility function. */
	//@param css : a 'css java' string like "{\nbackground: red;\n}".
	if (provider == 0) {
	provider = GTK.gtk_css_provider_new ();
	GTK.gtk_style_context_add_provider (context, provider, GTK.GTK_STYLE_PROVIDER_PRIORITY_APPLICATION);
	OS.g_object_unref (provider);
	}
	if (GTK.GTK4) {
	GTK.gtk_css_provider_load_from_data (provider, Converter.wcsToMbcs (css, true), -1);
	} else {
	GTK.gtk_css_provider_load_from_data (provider, Converter.wcsToMbcs (css, true), -1, null);
	}
	}

	@Override
	public void setImage (Image image) {
	checkWidget ();
	super.setImage (image);
	if (image != null) {
	ImageList imageList = parent.imageList;
	if (imageList == null) imageList = parent.imageList = new ImageList ();
	int imageIndex = imageList.indexOf (image);
	if (imageIndex == -1) {
	imageIndex = imageList.add (image);
	} else {
	imageList.put (imageIndex, image);
	}

	if (GTK.GTK4) {
	GTK.gtk_image_set_from_pixbuf(imageHandle, imageList.getPixbuf(imageIndex));
	} else {
	GTK.gtk_image_set_from_surface(imageHandle, image.surface);
	}
	GTK.gtk_widget_show(imageHandle);
	} else {
	if (GTK.GTK4) {
	GTK.gtk_image_clear(imageHandle);
	} else {
	GTK.gtk_image_set_from_surface(imageHandle, 0);
	}
	GTK.gtk_widget_hide(imageHandle);
	}
	}

	@Override
	void setOrientation (boolean create) {
	if ((parent.style & SWT.RIGHT_TO_LEFT) != 0 \|\| !create) {
	int dir = (parent.style & SWT.RIGHT_TO_LEFT) != 0 ? GTK.GTK_TEXT_DIR_RTL : GTK.GTK_TEXT_DIR_LTR;
	if (handle != 0) GTK.gtk_widget_set_direction (handle, dir);
	if (labelHandle != 0) GTK.gtk_widget_set_direction (labelHandle, dir);
	if (imageHandle != 0) GTK.gtk_widget_set_direction (imageHandle, dir);
	if (pageHandle != 0) GTK.gtk_widget_set_direction (pageHandle, dir);
	}
	}

	/**
	* Sets the receiver's text. The string may include
	* the mnemonic character.
	* <p>
	* Mnemonics are indicated by an '&' that causes the next
	* character to be the mnemonic. When the user presses a
	* key sequence that matches the mnemonic, a selection
	* event occurs. On most platforms, the mnemonic appears
	* underlined but may be emphasised in a platform specific
	* manner. The mnemonic indicator character '&' can be
	* escaped by doubling it in the string, causing a single
	* '&' to be displayed.
	* </p>
	*
	* @param string the new text
	*
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_NULL_ARGUMENT - if the text is null</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>
	*
	*/
	@Override
	public void setText (String string) {
	checkWidget ();
	if (string == null) error (SWT.ERROR_NULL_ARGUMENT);
	super.setText (string);
	char [] chars = fixMnemonic (string);
	byte [] buffer = Converter.wcsToMbcs (chars, true);
	GTK.gtk_label_set_text_with_mnemonic (labelHandle, buffer);
	if (string.length () != 0) {
	GTK.gtk_widget_show (labelHandle);
	} else {
	GTK.gtk_widget_hide (labelHandle);
	}
	}

	/**
	* Sets the receiver's tool tip text to the argument, which
	* may be null indicating that the default tool tip for the
	* control will be shown. For a control that has a default
	* tool tip, such as the Tree control on Windows, setting
	* the tool tip text to an empty string replaces the default,
	* causing no tool tip text to be shown.
	* <p>
	* The mnemonic indicator (character '&') is not displayed in a tool tip.
	* To display a single '&' in the tool tip, the character '&' can be
	* escaped by doubling it in the string.
	* </p>
	* <p>
	* NOTE: This operation is a hint and behavior is platform specific, on Windows
	* for CJK-style mnemonics of the form " (&C)" at the end of the tooltip text
	* are not shown in tooltip.
	* </p>
	*
	* @param string the new tool tip text (or 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 void setToolTipText (String string) {
	checkWidget ();
	Shell shell = parent._getShell ();
	shell.setToolTipText (handle, string);
	toolTipText = string;
	}

	@Override
	long dpiChanged(long object, long arg0) {
	super.dpiChanged(object, arg0);

	if (image != null) {
	image.internal_gtk_refreshImageForZoom();
	setImage(image);
	}

	return 0;
	}
	}