bundles/org.eclipse.ui/Eclipse UI Text Editor/org/eclipse/ui/texteditor/AbstractRulerActionDelegate.java

/**********************************************************************
Copyright (c) 2000, 2002 IBM 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:
    IBM Corporation - Initial API and implementation
**********************************************************************/
package org.eclipse.ui.texteditor;

import org.eclipse.jface.action.IAction;
import org.eclipse.jface.text.source.IVerticalRulerInfo;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseListener;
import org.eclipse.swt.widgets.Control;
import org.eclipse.ui.IEditorActionDelegate;
import org.eclipse.ui.IEditorPart;

/**
 * This class serves as an adapter for ruler actions.
 * Extending classes must implement the factory method
 * <code>createAction(ITextEditor editor, IVerticalRulerInfo)</code>.
 */
public abstract class AbstractRulerActionDelegate implements IEditorActionDelegate, MouseListener {

	private IEditorPart fEditor;
	private IAction fCallerAction;
	private IAction fAction;

	/*
	 * @see IEditorActionDelegate#setActiveEditor(IAction, IEditorPart)
	 */
	public void setActiveEditor(IAction callerAction, IEditorPart targetEditor) {
		if (fEditor != null) {
			IVerticalRulerInfo rulerInfo= (IVerticalRulerInfo) fEditor.getAdapter(IVerticalRulerInfo.class);
			if (rulerInfo != null)
				rulerInfo.removeMouseListener(this);
		}

		fEditor= targetEditor;		
		fCallerAction= callerAction;
		fAction= null;

		if (fEditor != null && fEditor instanceof ITextEditor) {
			IVerticalRulerInfo rulerInfo= (IVerticalRulerInfo) fEditor.getAdapter(IVerticalRulerInfo.class);
			if (rulerInfo != null) {
				fAction= createAction((ITextEditor) fEditor, rulerInfo);
				update();
				rulerInfo.addMouseListener(this);
			}
		}
	}

	/*
	 * @see IActionDelegate#run(IAction)
	 */
	public void run(IAction callerAction) {
		if (fAction != null)
			fAction.run();
	}

	/*
	 * @see IActionDelegate#selectionChanged(IAction, ISelection)
	 */
	public void selectionChanged(IAction action, ISelection selection) {
	}

	/**
	 * The factory method creating the underlying action.
	 */
	protected abstract IAction createAction(ITextEditor editor, IVerticalRulerInfo rulerInfo);

	/*
	 * @see MouseListener#mouseDoubleClick(MouseEvent)	
	 */
	public void mouseDoubleClick(MouseEvent e) {
	}

	/*
	 * @see MouseListener#mouseDown(MouseEvent)	
	 */
	public void mouseDown(MouseEvent e) {
		update();
	}

	/*
	 * @see MouseListener#mouseUp(MouseEvent)
	 */
	public void mouseUp(MouseEvent e) {
	}

	private void update() {
		if (fAction != null && fAction instanceof IUpdate) {
			((IUpdate) fAction).update();
			if (fCallerAction != null) {
				fCallerAction.setText(fAction.getText());
				fCallerAction.setEnabled(fAction.isEnabled());
			}
		}
	}
}