KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > eclipse > jdt > internal > junit > util > SWTUtil


1 /*******************************************************************************
2  * Copyright (c) 2000, 2004 IBM Corporation and others.
3  * All rights reserved. This program and the accompanying materials
4  * are made available under the terms of the Common Public License v1.0
5  * which accompanies this distribution, and is available at
6  * http://www.eclipse.org/legal/cpl-v10.html
7  *
8  * Contributors:
9  * IBM Corporation - initial API and implementation
10  *******************************************************************************/
11 package org.eclipse.jdt.internal.junit.util;
12
13
14 import org.eclipse.swt.SWT;
15 import org.eclipse.swt.dnd.DragSource;
16 import org.eclipse.swt.dnd.DropTarget;
17 import org.eclipse.swt.layout.GridData;
18 import org.eclipse.swt.widgets.Button;
19 import org.eclipse.swt.widgets.Caret;
20 import org.eclipse.swt.widgets.Control;
21 import org.eclipse.swt.widgets.Display;
22 import org.eclipse.swt.widgets.Menu;
23 import org.eclipse.swt.widgets.ScrollBar;
24 import org.eclipse.swt.widgets.Shell;
25 import org.eclipse.swt.widgets.Widget;
26
27 import org.eclipse.jface.dialogs.IDialogConstants;
28 import org.eclipse.jface.resource.JFaceResources;
29 import org.eclipse.jface.util.Assert;
30
31 /**
32  * Utility class to simplify access to some SWT resources.
33  * (copied from jdt ui)
34  */
35 public class SWTUtil {
36     private SWTUtil(){}
37     /**
38      * Returns the standard display to be used. The method first checks, if
39      * the thread calling this method has an associated disaply. If so, this
40      * display is returned. Otherwise the method returns the default display.
41      */
42     public static Display getStandardDisplay() {
43         Display display;
44         display= Display.getCurrent();
45         if (display == null)
46             display= Display.getDefault();
47         return display;
48     }
49     
50     /**
51      * Returns the shell for the given widget. If the widget doesn't represent
52      * a SWT object that manage a shell, <code>null</code> is returned.
53      *
54      * @return the shell for the given widget
55      */
56     public static Shell getShell(Widget widget) {
57         if (widget instanceof Control)
58             return ((Control)widget).getShell();
59         if (widget instanceof Caret)
60             return ((Caret)widget).getParent().getShell();
61         if (widget instanceof DragSource)
62             return ((DragSource)widget).getControl().getShell();
63         if (widget instanceof DropTarget)
64             return ((DropTarget)widget).getControl().getShell();
65         if (widget instanceof Menu)
66             return ((Menu)widget).getParent().getShell();
67         if (widget instanceof ScrollBar)
68             return ((ScrollBar)widget).getParent().getShell();
69                             
70         return null;
71     }
72
73
74     /**
75      * Returns a width hint for a button control.
76      */
77     public static int getButtonWidthHint(Button button) {
78         button.setFont(JFaceResources.getDialogFont());
79         PixelConverter converter= new PixelConverter(button);
80         int widthHint= converter.convertHorizontalDLUsToPixels(IDialogConstants.BUTTON_WIDTH);
81         return Math.max(widthHint, button.computeSize(SWT.DEFAULT, SWT.DEFAULT, true).x);
82     }
83
84     /**
85      * Returns a height hint for a button control.
86      */
87     public static int getButtonHeigthHint(Button button) {
88         button.setFont(JFaceResources.getDialogFont());
89         PixelConverter converter= new PixelConverter(button);
90         return converter.convertVerticalDLUsToPixels(IDialogConstants.BUTTON_HEIGHT);
91     }
92
93     
94     /**
95      * Sets width and height hint for the button control.
96      * <b>Note:</b> This is a NOP if the button's layout data is not
97      * an instance of <code>GridData</code>.
98      *
99      * @param button the button for which to set the dimension hint
100      */
101     public static void setButtonDimensionHint(Button button) {
102         Assert.isNotNull(button);
103         Object JavaDoc gd= button.getLayoutData();
104         if (gd instanceof GridData) {
105             ((GridData)gd).heightHint= getButtonHeigthHint(button);
106             ((GridData)gd).widthHint= getButtonWidthHint(button);
107         }
108     }
109     
110
111 }
112
Popular Tags