How to implement content assist's documentation popup in Eclipse RCP

Question

I have implemented my own editor and added a code completion functionality to it. My content assistant is registered in source viewer configuration like this:

public IContentAssistant getContentAssistant(ISourceViewer sourceViewer) {
    if (assistant == null) {
        assistant = new ContentAssistant();
        assistant.setDocumentPartitioning(getConfiguredDocumentPartitioning(sourceViewer));
        assistant.setContentAssistProcessor(getMyAssistProcessor(),
                MyPartitionScanner.DESIRED_PARTITION_FOR_MY_ASSISTANCE);
        assistant.enableAutoActivation(true);
        assistant.setAutoActivationDelay(500);
        assistant.setProposalPopupOrientation(IContentAssistant.PROPOSAL_OVERLAY);
        assistant.setContextInformationPopupOrientation(IContentAssistant.CONTEXT_INFO_ABOVE);
    }
    return assistant;
}

When I press Ctrl + SPACE inside the desired partition, the completion popup appears and works as expected.

And here's my question.. How do I implement/register a documentation popup that appears next to completion popup? (For example in java editor)

Answer 1

Well,

I'll answear the question myself ;-)

You have to add this line

assistant.setInformationControlCreator(getInformationControlCreator(sourceViewer));

to the configuration above. Then when creating CompletionProposals, the eighth (last) parameter called additionalProposalInfo of the constructor is the text, which will be shown in the documentation popup.

new CompletionProposal(replacementString,
                          replacementOffset,
                          replacementLength,
                          cursorPosition,
                          image,
                          displayString,
                          contextInformation,
                          additionalProposalInfo);

More information about can be found here.

Easy, isn't it.. if you know how to do it ;)

Answer 2

For the styled information box (just like in JDT).

---

The DefaultInformationControl instance need to received a HTMLTextPresenter.

import org.eclipse.jface.internal.text.html.HTMLTextPresenter;

public class MyConfiguration extends SourceViewerConfiguration {


    [...]
    public IContentAssistant getContentAssistant(ISourceViewer sourceViewer) {
        if (assistant == null) {
            [...]
            assistant.setInformationControlCreator(getInformationControlCreator(sourceViewer));
        }
        return assistant;
    }

    @Override
    public IInformationControlCreator getInformationControlCreator(ISourceViewer sourceViewer) {
        return new IInformationControlCreator() {
            public IInformationControl createInformationControl(Shell parent) {
                return new DefaultInformationControl(parent,new HTMLTextPresenter(false));
            }
        };
    }
}

Proposals can then use basic HTML tags in the string from method getAdditionalProposalInfo().

public class MyProposal implements ICompletionProposal {
    [...]
    @Override
    public String getAdditionalProposalInfo() {
        return "<b>Hello</b> <i>World</i>!";
    }
}