bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/internal/LayoutPart.java

package org.eclipse.ui.internal;

/******************************************************************************* 
 * Copyright (c) 2000, 2003 IBM Corporation and others. 
 * All rights reserved. This program and the accompanying materials! 
 * are 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 
 * 
 * Contributors: 
 *    IBM Corporation - initial API and implementation 
 *    Cagatay Kavukcuoglu <cagatayk@acm.org>
 *      - Fix for bug 10025 - Resizing views should not use height ratios
**********************************************************************/

import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.ListenerList;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.window.Window;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.ui.IWorkbenchWindow;

/**
 * A presentation part is used to build the presentation for the
 * workbench.  Common subclasses are pane and folder.
 */
abstract public class LayoutPart implements IPartDropTarget {
	protected ILayoutContainer container;
	protected String id;

	private Boolean visible;
	private ListenerList propertyListeners = new ListenerList(1);
	
	public static final String PROP_VISIBILITY = "PROP_VISIBILITY"; //$NON-NLS-1$
	
/**
 * PresentationPart constructor comment.
 */
public LayoutPart(String id) {
	super();
	this.id = id;
}
/**
 * Adds a property change listener to this action.
 * Has no effect if an identical listener is already registered.
 *
 * @param listener a property change listener
 */
public void addPropertyChangeListener(IPropertyChangeListener listener) {
	propertyListeners.add(listener);
}
/**
 * Removes the given listener from this action.
 * Has no effect if an identical listener is not registered.
 *
 * @param listener a property change listener
 */
public void removePropertyChangeListener(IPropertyChangeListener listener) {
	propertyListeners.remove(listener);
}
/**
 * Creates the SWT control
 */
abstract public void createControl(Composite parent);
/** 
 * Disposes the SWT control
 */
public void dispose() {
}
/**
 * Gets the presentation bounds.
 */
public Rectangle getBounds() {
	return new Rectangle(0, 0, 0, 0);
}
/**
 * Gets root container for this part.
 */
public RootLayoutContainer getRootContainer() {
	if(container != null)
		return container.getRootContainer();
	return null;
}
/**
 * Gets the parent for this part.
 */
public ILayoutContainer getContainer() {
	return container;
}
/**
 * Get the part control.  This method may return null.
 */
abstract public Control getControl();

/**
 * Gets the ID for this part.
 */
public String getID() {
	return id;
}
/**
 * Return the place the preferences used by layout parts reside.
 * @return IPreferenceStore
 */
/*package*/ IPreferenceStore getPreferenceStore() {
	return WorkbenchPlugin.getDefault().getPreferenceStore();		
}
/**
 * Return whether the window's shell is activated
 */
/* package */ boolean getShellActivated() {
	Window window = getWindow();
	if (window instanceof WorkbenchWindow) 
		return ((WorkbenchWindow) window).getShellActivated();
	else
		return false;
}
/**
 * Gets the presentation size.
 */
public Point getSize() {
	Rectangle r = getBounds();
	Point ptSize = new Point(r.width, r.height);
	return ptSize;
}

// getMinimumWidth() added by cagatayk@acm.org 
/**
 * Returns the minimum width a part can have. Subclasses may
 * override as necessary.
 */
public int getMinimumWidth() {
	return 0;
}

// getMinimumHeight() added by cagatayk@acm.org 
/**
 * Returns the minimum height a part can have. Subclasses may 
 * override as necessary.
 */
public int getMinimumHeight() {
	return 0;
}

/**
 * Returns the top level window for a part.
 */
public Window getWindow() {
	Control ctrl = getControl();
	if (ctrl != null) {
		Object data = ctrl.getShell().getData();
		if (data instanceof Window)
			return (Window)data;
	}
	return null;
}
/**
 * Returns the workbench window window for a part.
 */
public IWorkbenchWindow getWorkbenchWindow() {
	Window parentWindow = getWindow();
	if (parentWindow instanceof IWorkbenchWindow)
		return (IWorkbenchWindow)parentWindow;
	if (parentWindow instanceof DetachedWindow)
	 	return ((DetachedWindow)parentWindow).getWorkbenchPage().getWorkbenchWindow();
		 
	return null;
}
/**
 *	Allow the layout part to determine if they are in
 * an acceptable state to start a drag & drop operation.
 */
public boolean isDragAllowed(Point p) {
	return true;
}
/**
 * Move the control over another one.
 */
public void moveAbove(Control refControl) {
}
/**
 * Reparent a part.
 */
public void reparent(Composite newParent) {
	if (!newParent.isReparentable())
		return;
		
	Control control = getControl();
	if ((control == null) || (control.getParent() == newParent))
		return;
		
	// make control small in case it is not resized with other controls
	control.setBounds(0, 0, 0, 0);
	// By setting the control to disabled before moving it,
	// we ensure that the focus goes away from the control and its children
	// and moves somewhere else
	boolean enabled = control.getEnabled();
	control.setEnabled(false);
	control.setParent(newParent);
	control.setEnabled(enabled);
}
/**
 * Returns true if this part is visible.
 */
public boolean isVisible() {
	Control ctrl = getControl();
	if (ctrl != null)
		return visible == Boolean.TRUE ? true : false;
	return false;
}
/**
 * Shows the receiver if <code>visible</code> is true otherwise hide it.
 */
public void setVisible(boolean makeVisible) {
	Control ctrl = getControl();
	if (ctrl != null) {
		if(visible != null && makeVisible == visible.booleanValue())
			return;
		
		visible = makeVisible ? Boolean.TRUE : Boolean.FALSE;
		ctrl.setVisible(makeVisible);
		final Object[] listeners = propertyListeners.getListeners();
		if (listeners.length > 0) {
			Boolean oldValue = makeVisible ? Boolean.FALSE : Boolean.TRUE;
			PropertyChangeEvent event = new PropertyChangeEvent(this,PROP_VISIBILITY, oldValue,visible);
			for (int i = 0; i < listeners.length; ++i)
				((IPropertyChangeListener)listeners[i]).propertyChange(event);
		}
	}
}
/**
 * Sets the presentation bounds.
 */
public void setBounds(Rectangle r) {
	Control ctrl = getControl();
	if (ctrl != null)
		ctrl.setBounds(r);
}
/**
 * Sets the parent for this part.
 */
public void setContainer(ILayoutContainer container) {
	this.container = container;
}
/**
 * Sets focus to this part.
 */
public void setFocus() {
}
/** 
 * Sets the part ID.
 */
public void setID(String str) {
	id = str;
}
/**
 * @see IPartDropTarget::targetPartFor
 */
public LayoutPart targetPartFor(LayoutPart dragSource) {
	return null;
}
}