bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ViewerLabel.java

/*******************************************************************************
 * Copyright (c) 2004, 2007 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
 *     Tom Schindl <tom.shindl@bestsolution.at> - tooltip support
 *******************************************************************************/
package org.eclipse.jface.viewers;

import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;

/**
 * The ViewerLabel is the class that is passed to a viewer to handle updates of
 * labels. It keeps track of both original and updates text.
 * 
 * @see IViewerLabelProvider
 * @since 3.0
 */
public class ViewerLabel {

	// New values for the receiver. Null if nothing has been set.
	private String newText = null;

	private Image newImage = null;

	private boolean imageUpdated = false;

	private boolean textUpdated = false;

	private Color background = null;

	private Color foreground = null;

	private Font font = null;

	// The initial values for the receiver.
	private String startText;

	private Image startImage;

	private boolean hasPendingDecorations;

	private String tooltipText;

	private Color tooltipForegroundColor;

	private Color tooltipBackgroundColor;

	private Point tooltipShift;

	/**
	 * Create a new instance of the receiver with the supplied initial text and
	 * image.
	 * 
	 * @param initialText
	 * @param initialImage
	 */
	public ViewerLabel(String initialText, Image initialImage) {
		startText = initialText;
		startImage = initialImage;
	}

	/**
	 * Get the image for the receiver. If the new image has been set return it,
	 * otherwise return the starting image.
	 * 
	 * @return Returns the image.
	 */
	public final Image getImage() {
		if (imageUpdated) {
			return newImage;
		}
		return startImage;
	}

	/**
	 * Set the image for the receiver.
	 * 
	 * @param image
	 *            The image to set.
	 */
	public final void setImage(Image image) {
		imageUpdated = true;
		newImage = image;
	}

	/**
	 * Get the text for the receiver. If the new text has been set return it,
	 * otherwise return the starting text.
	 * 
	 * @return String or <code>null</code> if there was no initial text and
	 *         nothing was updated.
	 */
	public final String getText() {
		if (textUpdated) {
			return newText;
		}
		return startText;
	}

	/**
	 * Set the text for the receiver.
	 * 
	 * @param text
	 *            String The label to set. This value should not be
	 *            <code>null</code>.
	 * @see #hasNewText()
	 */
	public final void setText(String text) {
		newText = text;
		textUpdated = true;
	}

	/**
	 * Return whether or not the image has been set.
	 * 
	 * @return boolean. <code>true</code> if the image has been set to
	 *         something new.
	 * 
	 * @since 3.1
	 */
	public boolean hasNewImage() {

		// If we started with null any change is an update
		if (startImage == null) {
			return newImage != null;
		}

		if (imageUpdated) {
			return !(startImage.equals(newImage));
		}
		return false;
	}

	/**
	 * Return whether or not the text has been set.
	 * 
	 * @return boolean. <code>true</code> if the text has been set to
	 *         something new.
	 */
	public boolean hasNewText() {

		// If we started with null any change is an update
		if (startText == null) {
			return newText != null;
		}

		if (textUpdated) {
			return !(startText.equals(newText));
		}

		return false;
	}

	/**
	 * Return whether or not the background color has been set.
	 * 
	 * @return boolean. <code>true</code> if the value has been set.
	 */
	public boolean hasNewBackground() {
		return background != null;
	}

	/**
	 * Return whether or not the foreground color has been set.
	 * 
	 * @return boolean. <code>true</code> if the value has been set.
	 * 
	 * @since 3.1
	 */
	public boolean hasNewForeground() {
		return foreground != null;
	}

	/**
	 * Return whether or not the font has been set.
	 * 
	 * @return boolean. <code>true</code> if the value has been set.
	 * 
	 * @since 3.1
	 */
	public boolean hasNewFont() {
		return font != null;
	}

	/**
	 * Get the background Color.
	 * 
	 * @return Color or <code>null</code> if no new value was set.
	 * 
	 * @since 3.1
	 */
	public Color getBackground() {
		return background;
	}

	/**
	 * Set the background Color.
	 * 
	 * @param background
	 *            Color. This value should not be <code>null</code>.
	 * 
	 * @since 3.1
	 */
	public void setBackground(Color background) {
		this.background = background;
	}

	/**
	 * Get the font.
	 * 
	 * @return Font or <code>null</code> if no new value was set.
	 * 
	 * @since 3.1
	 */
	public Font getFont() {
		return font;
	}

	/**
	 * Set the font.
	 * 
	 * @param font
	 *            Font This value should not be <code>null</code>.
	 * 
	 * @since 3.1
	 */
	public void setFont(Font font) {
		this.font = font;
	}

	/**
	 * Get the foreground Color.
	 * 
	 * @return Color or <code>null</code> if no new value was set.
	 * 
	 * @since 3.1
	 */
	public Color getForeground() {
		return foreground;
	}

	/**
	 * Set the foreground Color.
	 * 
	 * @param foreground
	 *            Color This value should not be <code>null</code>.
	 * 
	 * @since 3.1
	 */
	public void setForeground(Color foreground) {
		this.foreground = foreground;
	}

	/**
	 * Set whether or not there are any decorations pending.
	 * 
	 * @param hasPendingDecorations
	 */
	void setHasPendingDecorations(boolean hasPendingDecorations) {
		this.hasPendingDecorations = hasPendingDecorations;
	}

	/**
	 * @return <code>boolean</code>. <code>true</code> if there are any
	 *         decorations pending.
	 */
	boolean hasPendingDecorations() {
		return hasPendingDecorations;
	}

	/**
	 * Returns the tooltipText.
	 * 
	 * @return {@link String} or <code>null</code> if the tool tip text was
	 *         never set.
	 * 
	 * @since 3.3
	 */
	public String getTooltipText() {
		return tooltipText;
	}

	/**
	 * Set the tool tip text.
	 * 
	 * @param tooltipText
	 *            The tooltipText {@link String} to set. This value should not
	 *            be <code>null</code>.
	 * 
	 * @since 3.3
	 */
	public void setTooltipText(String tooltipText) {
		this.tooltipText = tooltipText;
	}

	/**
	 * Return whether or not the tool tip text has been set.
	 * 
	 * @return <code>boolean</code>. <code>true</code> if the tool tip text
	 *         has been set.
	 * 
	 * @since 3.3
	 */
	public boolean hasNewTooltipText() {
		return this.tooltipText != null;
	}

	/**
	 * Return the tool tip background color.
	 * 
	 * @return {@link Color} or <code>null</code> if the tool tip background
	 *         color has not been set.
	 * 
	 * @since 3.3
	 */
	public Color getTooltipBackgroundColor() {
		return tooltipBackgroundColor;
	}

	/**
	 * Set the background {@link Color} for tool tip.
	 * 
	 * @param tooltipBackgroundColor
	 *            The {@link Color} to set. This value should not be
	 *            <code>null</code>.
	 * 
	 * @since 3.3
	 */
	public void setTooltipBackgroundColor(Color tooltipBackgroundColor) {
		this.tooltipBackgroundColor = tooltipBackgroundColor;
	}

	/**
	 * Return whether or not the tool tip background color has been set.
	 * 
	 * @return <code>boolean</code>. <code>true</code> if the tool tip text
	 *         has been set.
	 * 
	 * @since 3.3
	 */
	public boolean hasNewTooltipBackgroundColor() {
		return tooltipBackgroundColor != null;
	}

	/**
	 * Return the foreground {@link Color}.
	 * 
	 * @return Returns {@link Color} or <code>null</code> if the tool tip
	 *         foreground color has not been set.
	 * 
	 * @since 3.3
	 */
	public Color getTooltipForegroundColor() {
		return tooltipForegroundColor;
	}

	/**
	 * Set the foreground {@link Color} for tool tip.
	 * 
	 * @param tooltipForegroundColor
	 *            The tooltipForegroundColor to set.
	 *            
	 * @since 3.3
	 */
	public void setTooltipForegroundColor(Color tooltipForegroundColor) {
		this.tooltipForegroundColor = tooltipForegroundColor;
	}

	/**
	 * 
	 * Return whether or not the tool tip foreground color has been set.
	 * 
	 * @return <code>boolean</code>. <code>true</code> if the tool tip foreground
	 *         has been set.
	 * 
	 * @since 3.3
	 */
	public boolean hasNewTooltipForegroundColor() {
		return tooltipForegroundColor != null;
	}

	/**
	 * @return Returns the tooltipShift.
	 * @since 3.3
	 */
	public Point getTooltipShift() {
		return tooltipShift;
	}

	/**
	 * @param tooltipShift
	 *            The tooltipShift to set.
	 * @since 3.3
	 */
	public void setTooltipShift(Point tooltipShift) {
		this.tooltipShift = tooltipShift;
	}

	/**
	 * @return Return whether or not the tool tip shift has been set.
	 * @since 3.3
	 */
	public boolean hasTooltipShift() {
		return this.tooltipShift != null;
	}
}