examples/org.eclipse.swt.examples/src/org/eclipse/swt/examples/controlexample/AlignableTab.java

/*******************************************************************************
 * 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 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.swt.examples.controlexample;


import org.eclipse.swt.*;
import org.eclipse.swt.widgets.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.events.*;

/**
 * <code>AlignableTab</code> is the abstract
 * superclass of example controls that can be
 * aligned.
 */
abstract class AlignableTab extends Tab {

	/* Alignment Controls */
	Button leftButton, rightButton, centerButton;

	/* Alignment Group */
	Group alignmentGroup;

	/**
	 * Creates the Tab within a given instance of ControlExample.
	 */
	AlignableTab(ControlExample instance) {
		super(instance);
	}

	/**
	 * Creates the "Control" group. 
	 */
	void createControlGroup () {
		super.createControlGroup ();
		
		/* Create the group */
		alignmentGroup = new Group (controlGroup, SWT.NONE);
		alignmentGroup.setLayout (new GridLayout ());
		alignmentGroup.setLayoutData (new GridData(GridData.HORIZONTAL_ALIGN_FILL |
			GridData.VERTICAL_ALIGN_FILL));
		alignmentGroup.setText (ControlExample.getResourceString("Alignment"));
	
		/* Create the controls */
		leftButton = new Button (alignmentGroup, SWT.RADIO);
		leftButton.setText (ControlExample.getResourceString("Left"));
		centerButton = new Button (alignmentGroup, SWT.RADIO);
		centerButton.setText(ControlExample.getResourceString("Center"));
		rightButton = new Button (alignmentGroup, SWT.RADIO);
		rightButton.setText (ControlExample.getResourceString("Right"));
	
		/* Add the listeners */
		SelectionListener selectionListener = new SelectionAdapter () {
			public void widgetSelected(SelectionEvent event) {
				if (!((Button) event.widget).getSelection ()) return;
				setExampleWidgetAlignment ();
			}
		};
		leftButton.addSelectionListener (selectionListener);
		centerButton.addSelectionListener (selectionListener);
		rightButton.addSelectionListener (selectionListener);
	}
	
	/**
	 * Sets the alignment of the "Example" widgets.
	 */
	abstract void setExampleWidgetAlignment ();
	
	/**
	 * Sets the state of the "Example" widgets.
	 */
	void setExampleWidgetState () {
		super.setExampleWidgetState ();
		Control [] controls = getExampleWidgets ();
		if (controls.length != 0) {
			leftButton.setSelection ((controls [0].getStyle () & SWT.LEFT) != 0);
			centerButton.setSelection ((controls [0].getStyle () & SWT.CENTER) != 0);
			rightButton.setSelection ((controls [0].getStyle () & SWT.RIGHT) != 0);
		}
	}
}