Bug 148357 [Field Assist] - API - provide access for closing the proposal popup
I think that the field assist API needs more hooks to be customizable. For example : 1) There is no way to manually close/open the popup. Most of the times, this is the easier thing for a user to ask to implement his custom behaviour. 2) There is no way to intercept keystrokes/events directed to the field. 3) There is no way to control focus.
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
* Constructs a new instance of this popup, specifying the control for
		 * which this popup is showing content, and how the proposals should be
		 * obtained and displayed.
		 * 
		 * @param infoText
		 *            Text to be shown in a lower info area, or
		 *            <code>null</code> if there is no info area.
		 */
		ContentProposalPopup(String infoText, IContentProposal[] proposals) {
			
			
			
			
			
			
			
			super(control.getShell(), SWT.RESIZE | SWT.ON_TOP, false, false,
					false, false, null, infoText);
			this.proposals = proposals;
		}
		/*
		 * Overridden to force change of colors.
		 * See https://bugs.eclipse.org/bugs/show_bug.cgi?id=136244
		 * (non-Javadoc)
		 * @see org.eclipse.jface.dialogs.PopupDialog#createContents(org.eclipse.swt.widgets.Composite)
		 */
		protected Control createContents(Composite parent) {
			Control contents = super.createContents(parent);
			changeDefaultColors(parent);
			return contents;