ColorField.java

package org.sigmah.client.ui.widget;

/*
 * #%L
 * Sigmah
 * %%
 * Copyright (C) 2010 - 2016 URD
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-3.0.html>.
 * #L%
 */

import com.extjs.gxt.ui.client.event.ColorPaletteEvent;
import com.extjs.gxt.ui.client.event.ComponentEvent;
import com.extjs.gxt.ui.client.event.Events;
import com.extjs.gxt.ui.client.event.Listener;
import com.extjs.gxt.ui.client.widget.form.TriggerField;
import com.extjs.gxt.ui.client.widget.menu.ColorMenu;
import com.google.gwt.user.client.Element;

/**
 * GXT Field that allows users to select a color from a standard palette
 *
 * @author Alex Bertram v1.3
 * @author Mehdi Benabdeslam (mehdi.benabdeslam@netapsys.fr) v2.0
 */
public class ColorField extends TriggerField<String> {

	private static final String WHITE_HEX_STRING = "FFFFFF";
	private static final int WHITE = 0xFFFFF;

	public ColorField() {
		setEditable(false);
	}

	@Override
	protected void onTriggerClick(ComponentEvent ce) {
		super.onTriggerClick(ce);
		ColorMenu menu = new ColorMenu();
		menu.getColorPalette().addListener(Events.Select, new Listener<ColorPaletteEvent>() {

			@Override
			public void handleEvent(ColorPaletteEvent ce) {
				setValue(ce.getColor());
			}
		});
		menu.show(getElement(), "b");
	}

	/**
	 * Sets the field's current value
	 *
	 * @param value
	 *          the color value, as a hex string, WITHOUT preceding '#', e.g. FFFFFF
	 */
	@Override
	public void setValue(String value) {
		super.setValue(value);
		if (isRendered()) {
			input.setStyleAttribute("backgroundColor", "#" + (value == null ? WHITE_HEX_STRING : value));
		}
	}

	@Override
	public void render(Element target, int index) {
		super.render(target, index);
		input.setStyleAttribute("backgroundColor", "#" + (value == null ? WHITE_HEX_STRING : value));
		input.setStyleAttribute("backgroundImage", "none");
	}

	/**
	 * @return the current color value as a 32-bit integer.
	 */
	public int getIntValue() {
		return value == null ? WHITE : Integer.parseInt(value, 16);
	}
}