Enhancing the Combo-Widget with Images(转载)

Probably you was already faced with the requirement to add small icons to your pulldowns. That looks very nice, but unfortunately there is no common SWT-Widget to realize this.
Fortunately the Eclipse-Framework is OpenSource and we can reprodruce the structure of a SWT-ComboBox. A Combo is not more than a text-field and a small button with an arrow. In addition is a event-handler implemented that shows a Composite as a tooltip with the entries of the "combo-list". We just have to take this class and change the structure of the content. We don't want to have a org.eclipse.swt.widgets.List, but a org.eclipse.swt.widgets.Table with multiple org.eclipse.swt.widgets.TableItems where you can specify an image. After adjusting the access-methods we have a new cool Widget, that has the same structure and methods like the "built-in"s.

Screenshot

The ImageCombo in Action (as Widget in a JFace-Dialog).

Usage

• Download the JavaFile and copy it into your Java-Project.
• Reference the Widget like all the other ones.

Update

• ImageCombo.java with Corrections for GTK (Thanks to Jeremy Dowdall)
  

Code-Example

The following snippet show the usage in a very simple JFace-Dialog.

PLAIN TEXT

JAVA:

1. /**
2. * Very Simple Dialog with {@link org.eclipse.swt.widgets.Label}
3. * and a Combo that has the capability to show also icons.
4. * @author Tom Seidel
5. *
6. */
7. public class SimpleDialog extends Dialog {
8.      private List list;
9.      /**
10.       * @param parentShell
11.       * @param list
12.       */
13.      protected SimpleDialog(Shell parentShell, List list) {
14.          super(parentShell);
15.          this.list = list;
16.      }
17.      /* (non-Javadoc)
18.       * @see org.eclipse.jface.dialogs.Dialog#createDialogArea(org.eclipse.swt.widgets.Composite)
19.       */
20.      protected Control createDialogArea(Composite parent) {
21.          Composite comp = (Composite) super.createDialogArea(parent);
22.          comp.setLayout(new GridLayout(2,true));
23.          Label textLabel = new Label(comp,SWT.NONE);
24.          GridData gd = new GridData(SWT.BEGINNING, SWT.CENTER, false,false);
25.          gd.widthHint = 80;
26.          textLabel.setLayoutData(gd);
27.          textLabel.setText("Your choice:"); //$NON-NLS-1$
28.          ImageCombo combo = new ImageCombo(comp, SWT.READ_ONLY | SWT.BORDER);
29.          Iterator iter = this.list.iterator();
30.          while (iter.hasNext()) {
31.              AbstractBaseElement element = (AbstractBaseElement) iter.next();
32.              // add text and image to the combo.
33.              combo.add(element.getId(),ImagecontributionPlugin.getDefault()
34.                  .getImage(ImageContributor.getImageIdByObject(element)));
35.          }
36.          combo.setLayoutData(gd);
37.         return comp;
38.     }
39. }

转载:

http://www.richclient2.de/2006_03_03/enhancing-the-combo-widget-with-images/