Bug 144225 [FieldAssist] NullPointerException in ContentProposalAdapter$ContentProposalPopup.open()
I am using Eclipse 3.2RC6 and was playing around with the org.eclipse.jface.fieldassist package. I wanted to implement a simple auto-complete textfield with the ContentProposalAdapter class. But if the first letter which is entered in the textfield does not yield any proposals, the call to getSelectedProposal() in line 859 of ContentProposalAdapter.java returns null and therefore a NPE is thrown, rather than just not showing the popup at all. The following snippet shows this behaviour (just type any letter except "p"): import org.eclipse.jface.fieldassist.ContentProposalAdapter; import org.eclipse.jface.fieldassist.IContentProposal; import org.eclipse.jface.fieldassist.IContentProposalProvider; import org.eclipse.jface.fieldassist.TextContentAdapter; import org.eclipse.swt.SWT; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Shell; import org.eclipse.swt.widgets.Text; public class ExampleSnippet { public static void main(String[] args) { Display display = new Display(); Shell shell = new Shell(display); shell.setLayout(new FillLayout()); Text text = new Text(shell, SWT.NONE); ContentProposalAdapter adapter = new ContentProposalAdapter(text, new TextContentAdapter(), new TextProposalProvider(), null, null); adapter.setProposalAcceptanceStyle(ContentProposalAdapter.PROPOSAL_REPLACE); shell.setSize(200, text.getSize().y); shell.open(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } display.dispose(); } } class TextProposalProvider implements IContentProposalProvider { private String str = "Proposal"; public IContentProposal[] getProposals(String contents, int position) { IContentProposal[] proposals; if (str.toLowerCase().startsWith(contents.toLowerCase())) { proposals = new IContentProposal[1]; proposals[0] = new IContentProposal() { public String getContent() { return str; } public int getCursorPosition() { return str.length(); } public String getDescription() { return null; } public String getLabel() { return null; } }; } else { proposals = new IContentProposal[0]; } return proposals; } }
bundles/org.eclipse.jface/src/org/eclipse/jface/fieldassist/ContentProposalAdapter.java
/**
	 * Set the boolean flag that determines whether the adapter is enabled.
	 * 
	 * @param enabled
	 *            <code>true</code> if the adapter is enabled and responding
	 *            to user input, <code>false</code> if it is ignoring user
	 *            input.
	 * 
	 */
	public void setEnabled(boolean enabled) {
		
		
		if (isEnabled && !enabled) {
			if (popup != null) {
				popup.close();
			}
		}
		isEnabled = enabled;
	}
	/**
	 * Add the specified listener to the list of content proposal listeners that
	 * are notified when content proposals are chosen.
	 * </p>
	 * 
	 * @param listener
	 *            the IContentProposalListener to be added as a listener. Must
	 *            not be <code>null</code>. If an attempt is made to register
	 *            an instance which is already registered with this instance,
	 *            this method has no effect.
	 *