TitleControl.java

/*******************************************************************************
 * Copyright (c) 2008, 2012 Stepan Rutz.
 * 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:
 *    Stepan Rutz - initial implementation
 *******************************************************************************/

package org.eclipse.nebula.widgets.geomap.internal.geomapbrowser;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Composite;

/**
 * An owner-drawn title label type of swt-control.
 * 
 * @author stepan.rutz
 * @version $Revision$
 */
public class TitleControl extends Canvas {
    
    private static final int TOP_SPACE = 0;
    private Font font;
    private Color gradient1Color;
    private Color gradient2Color;
    private Color bottomLineColor;
    private Color writingColor;
    private Image image;
    private String text = "";
    private Point size = new Point(1, 1);
    
    public TitleControl(Composite parent, Image image) {
        super(parent, SWT.DOUBLE_BUFFERED);
        addPaintListener(new PaintListener() {
            public void paintControl(PaintEvent e) {
                onPaint(e);
            }
        });
        addDisposeListener(new DisposeListener() {
            public void widgetDisposed(DisposeEvent e) {
                onDispose(e);
            }
        });
        
        font = new Font(getDisplay(), "Tahoma", 10, SWT.BOLD);
        gradient1Color = new Color(getDisplay(), 255, 255, 255);
        gradient2Color = new Color(getDisplay(), 205, 224, 244);
        bottomLineColor = new Color(getDisplay(), 200, 195, 216);
        writingColor = new Color(getDisplay(), 60, 60, 60);
        this.image = image;

        measureSize("M");
    }
    
    private void measureSize(String s) {
        GC gc = new GC(this);
        try {
            gc.setFont(font);
            size = gc.stringExtent(s);
            if (image != null) {
            	size.y = Math.max(image.getBounds().height + 1, size.y);
            } else {
            	size.y += 16;
            }
            size.y += TOP_SPACE;
        } finally {
            gc.dispose();
        }
    }

    private void onDispose(DisposeEvent e) {
        font.dispose();
        gradient1Color.dispose();
        gradient2Color.dispose();
        bottomLineColor.dispose();
        writingColor.dispose();
        if (image != null)
        	image.dispose();
    }

    private void onPaint(PaintEvent e) {
        GC gc = e.gc;
        Point s = getSize();
        int w = s.x;
        int h = s.y;
        
        gc.setForeground(gradient1Color);
        gc.setBackground(gradient2Color);
        gc.fillGradientRectangle(0, 0, w, h - 1, true);
        
        
        Rectangle imgsize = new Rectangle(0, 0, 0, 0);
        if (image != null) {
        	imgsize = image.getBounds();
        	gc.drawImage(image, 12, 0);
        }
        gc.setForeground(bottomLineColor);
        gc.drawLine(0, h - 1, w, h - 1);
        
        gc.setFont(font);
        gc.setForeground(writingColor);
        Point textSize = gc.stringExtent(text);
        int ty = (h - textSize.y) / 2;
        gc.drawString(text, 22 + imgsize.width, TOP_SPACE + ty, true);
    }
    
    public String getText() {
        return text;
    }
    
    public void setText(String text) {
        this.text = text;
        measureSize(text);
        redraw();
    }
    
    @Override
    public Point computeSize(int wHint, int hHint, boolean changed) {
        return new Point(size.x, size.y);
    }
    
    
}