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

package org.eclipse.ui.internal;

/**********************************************************************
Copyright (c) 2000, 2001, 2002, International Business Machines Corp and others.
All rights reserved.   This program and the accompanying materials
are made available under the terms of the Common Public License v0.5
which accompanies this distribution, and is available at
http://www.eclipse.org/legal/cpl-v05.html
 
Contributors:
  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";
	
/**
 * 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;
	/*
	 * Detached window no longer supported - remove when confirmed
	 *
	 * 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;
}
}