1 /******************************************************************************* 2 * Copyright (c) 2011 Google, Inc. 3 * All rights reserved. This program and the accompanying materials 4 * are made available under the terms of the Eclipse Public License v1.0 5 * which accompanies this distribution, and is available at 6 * http://www.eclipse.org/legal/epl-v10.html 7 * 8 * Contributors: 9 * Google, Inc. - initial API and implementation 10 *******************************************************************************/ 11 package org.eclipse.wb.core.controls; 12 13 import org.eclipse.swt.SWT; 14 import org.eclipse.swt.graphics.GC; 15 import org.eclipse.swt.graphics.Image; 16 import org.eclipse.swt.graphics.Point; 17 import org.eclipse.swt.graphics.Rectangle; 18 import org.eclipse.swt.widgets.Canvas; 19 import org.eclipse.swt.widgets.Composite; 20 import org.eclipse.swt.widgets.Event; 21 import org.eclipse.swt.widgets.Listener; 22 23 /** 24 * Simple control for displaying image and text. 25 * 26 * For unknown reason CLabel shows such things not very good - vertical text alignment is strange 27 * (bottom?). 28 * 29 * @author scheglov_ke 30 * @coverage core.control 31 */ 32 public class CImageLabel extends Canvas { 33 private static final int SPACE = 5; 34 private Image m_image; 35 private String m_text; 36 37 //////////////////////////////////////////////////////////////////////////// 38 // 39 // Constructor 40 // 41 //////////////////////////////////////////////////////////////////////////// 42 public CImageLabel(Composite parent, int style) { 43 super(parent, style | SWT.NO_BACKGROUND); 44 addListener(SWT.Dispose, new Listener() { 45 public void handleEvent(Event event) { 46 if (m_backImage != null) { 47 m_backImage.dispose(); 48 m_backImage = null; 49 } 50 } 51 }); 52 addListener(SWT.Paint, new Listener() { 53 public void handleEvent(Event event) { 54 doPaint(event.gc); 55 } 56 }); 57 } 58 59 //////////////////////////////////////////////////////////////////////////// 60 // 61 // Access 62 // 63 //////////////////////////////////////////////////////////////////////////// 64 public Image getImage() { 65 return m_image; 66 } 67 68 public void setImage(Image image) { 69 m_image = image; 70 redraw(); 71 } 72 73 public String getText() { 74 return m_text; 75 } 76 77 public void setText(String text) { 78 m_text = text; 79 redraw(); 80 } 81 82 //////////////////////////////////////////////////////////////////////////// 83 // 84 // Paint 85 // 86 //////////////////////////////////////////////////////////////////////////// 87 private Image m_backImage; 88 89 private void doPaint(GC paintGC) { 90 Rectangle clientArea = getClientArea(); 91 // prepare back image 92 GC gc; 93 { 94 if (m_backImage == null || !m_backImage.getBounds().equals(clientArea)) { 95 if (m_backImage != null) { 96 m_backImage.dispose(); 97 } 98 m_backImage = new Image(getDisplay(), clientArea.width, clientArea.height); 99 } 100 // 101 gc = new GC(m_backImage); 102 gc.setBackground(paintGC.getBackground()); 103 gc.setForeground(paintGC.getForeground()); 104 gc.fillRectangle(clientArea); 105 } 106 // 107 Point textExtent = m_text == null ? new Point(0, 0) : gc.textExtent(m_text); 108 Rectangle imageBounds = m_image == null ? new Rectangle(0, 0, 0, 0) : m_image.getBounds(); 109 // 110 if (m_image != null) { 111 int x = clientArea.x; 112 int y = clientArea.y + (clientArea.height - imageBounds.height) / 2; 113 gc.drawImage(m_image, x, y); 114 } 115 if (m_text != null) { 116 int x = clientArea.x + imageBounds.width + SPACE; 117 int y = clientArea.y + (clientArea.height - textExtent.y) / 2; 118 gc.drawText(m_text, x, y); 119 } 120 // flush back image 121 { 122 paintGC.drawImage(m_backImage, 0, 0); 123 gc.dispose(); 124 } 125 } 126 127 @Override 128 public Point computeSize(int wHint, int hHint, boolean changed) { 129 // prepare text size 130 GC gc = new GC(this); 131 Point textExtent = m_text == null ? new Point(0, 0) : gc.textExtent(m_text); 132 gc.dispose(); 133 // prepare image size 134 Rectangle imageBounds = m_image == null ? new Rectangle(0, 0, 0, 0) : m_image.getBounds(); 135 // calculate control size 136 int width = imageBounds.width + SPACE + textExtent.x; 137 int height = Math.max(imageBounds.height, textExtent.y); 138 return new Point(width, height); 139 } 140 } 141
