SWT Tree and tooltips

If you need tooltips for elements in an SWT Tree or JFace TreeViewer, you had to jump through some hoops as Snippet 125 shows.

Since SWT/JFace 3.3, you should use a TreeViewer, a ColumnLabelProvider (which has all those cool getTooltip…() methods) and this line of code:

ColumnViewerToolTipSupport.enableFor (viewer);

That’s it. There is a catch, though: The tooltip doesn’t wrap automatically. If you have long lines of text, you need commons-lang and this piece of code:

    private String wrap (String s)
    {
        StringBuilder buffer = new StringBuilder ();
        
        String delim = "";
        for (String line: s.trim ().split ("\n"))
        {
            buffer.append (delim);
            delim = "\n";
            buffer.append (WordUtils.wrap (line, 60, "\n", true));
        }
        
        return buffer.toString ();
    }

Note that this code is only necessary if you have several lines of text in the tooltip. For single long lines, WordUtils.wrap() alone is enough.

Link to the JFace snippet.