Customize properties

<back

This section is about customizing properties on the basis of an example.

What I want: My element A has a property of type B. B is something like a file so it has a property "path" of type String. I want a file chooser to choose the file. The path of the file should be stored in the path property of the property B of element A.

What to do:

• Write a class like the following. This is the file choose itself.

  public class FileChooserCellEditor extends DialogCellEditor {
  
     private Composite parent;
  	
     public FileChooserCellEditor(Composite parent) {
  	super(parent);
  	this.parent = parent;
     }
  
     protected Object openDialogBox(Control cellEditorWindow) {
  	FileDialog dialog = new FileDialog(parent.getShell(), SWT.OPEN);
  	return dialog.open();
     }
  }
  
  

• Write a property descriptor for all your properties:

  public class ExhibitionPropertyDescriptor extends
  		EMFCompositeSourcePropertyDescriptor {
  
     IItemPropertyDescriptor itemPropertyDescriptor;
  	
     public ExhibitionPropertyDescriptor(Object object,
  		IItemPropertyDescriptor itemPropertyDescriptor, String category) {
  	super(object, itemPropertyDescriptor, category);
  	this.itemPropertyDescriptor = itemPropertyDescriptor;
     }
  
     /* here you can instanciate whatever you want to be 
        opened when the user clicks on the button in the property field
     */
     protected CellEditor doCreateEditor(Composite composite) {
  	if (itemPropertyDescriptor instanceof ImagePropertyDescriptor) {
  	   return new FileChooserCellEditor(composite);
  	}
  	return super.doCreateEditor(composite);
     }
  }