sameshellprovider.java

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/*******************************************************************************
 * 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.jface.window;

import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;

/**
 * Standard shell provider that always returns the shell containing the given
 * control. This will always return the correct shell for the control, even if
 * the control is reparented.
 * 
 * @since 3.1
 */
public class SameShellProvider implements IShellProvider {

    private Control targetControl;
    
    /**
     * Returns a shell provider that always returns the current
     * shell for the given control.
     * 
     * @param targetControl control whose shell will be tracked, or null if getShell() should always
     * return null
     */
    public SameShellProvider(Control targetControl) {
        this.targetControl = targetControl;
    }
    
    /* (non-javadoc)
     * @see IShellProvider#getShell()
     */
    public Shell getShell() {
        if (targetControl instanceof Shell) {
            return (Shell)targetControl;
        }
        
        return targetControl == null? null :targetControl.getShell();
    }

}