shortintegerfieldeditor.java

Eclipse高级编程3源码(书本源码)

/*******************************************************************************
 * Copyright (c) 2003 Berthold Daum. 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: Berthold Daum
 ******************************************************************************/
package com.bdaum.SpellChecker.preferences;

import org.eclipse.jface.preference.StringFieldEditor;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Text;

public class ShortIntegerFieldEditor extends StringFieldEditor {
	private int minValidValue = 0;

	private int maxValidValue = Integer.MAX_VALUE;

	/**
	 * Default constructor.
	 */
	public ShortIntegerFieldEditor() {
		super();
	}

	/**
	 * Qualified constructor.
	 * 
	 * @param name -
	 *            preference key
	 * @param labelText -
	 *            label text string
	 * @param parent -
	 *            parent composite
	 * @param textLimit -
	 *            maximum text width
	 */
	public ShortIntegerFieldEditor(String name, String labelText,
			Composite parent, int width) {
		super(name, labelText, width, parent);
		setTextLimit(width);
		setEmptyStringAllowed(false);
		setErrorMessage(JFaceResources
				.getString("IntegerFieldEditor.errorMessage"));

	}

	/**
	 * Sets the range of valid values for this field.
	 * 
	 * @param min -
	 *            he minimum allowed value (inclusive)
	 * @param max -
	 *            the maximum allowed value (inclusive)
	 */
	public void setValidRange(int min, int max) {
		minValidValue = min;
		maxValidValue = max;
	}

	/**
	 * Checks for valid field content
	 * 
	 * @return - true if valid
	 */
	protected boolean checkState() {
		Text text = getTextControl();
		if (text == null)
			return false;
		String numberString = text.getText();
		try {
			int number = Integer.valueOf(numberString).intValue();
			if (number >= minValidValue && number <= maxValidValue) {
				clearErrorMessage();
				return true;
			}
		} catch (NumberFormatException e1) {
		}
		showErrorMessage();
		return false;
	}
}