Eclipse custom text editor update syntax highlighting - eclipse-plugin

Question

I am writing an Eclipse plugin (Indigo/Juno) that contains a text editor for a custom text format. I am following the tutorial here: http://www.realsolve.co.uk/site/tech/jface-text.php
So far I have everything working. Eclipse will use my editor to edit files. I have partitioning, damaging, repairing, syntax highlighting all working.
I added a preferences page with color pickers to control syntax highlighting. It works mostly correct. If I update the colors, the editor uses them the next time I open or reopen a file.
How do I get an editor tab to update itself without opening a new one? The built-in JDT Java editor does this, but so far I have not been able to decipher how (it is a very large and complex editor).
I gather that I need to create a preferences listener (http://www.vogella.com/articles/EclipsePreferences/article.html). I have done this and can verify that my listener code is being invoked when I set a breakpoint in it.
The missing piece is the wiring between the listener and reinitializing the editor. I have tried reconstructing the partitioning logic, the color logic, the damager/repairer, etc. but nothing seems to work. It either does nothing I can see or at worst will corrupt the display until I scroll the current text out of view to repaint it... with the old colors.
Any ideas?

Answer 1

I think SourceViewer.invalidatePresentation() needs to be called.

Answer 2

It may be already late to you, but if you want you could use LiClipse for that (http://brainwy.github.io/liclipse/) -- one of its targets is easily doing an editor with syntax highlighting, basic code-completion, outline, etc targeting Eclipse.
No java skills are required to add a new language (mostly creating a new .liclipse -- which is a YAML -- file in the proper place and creating some basic rules to say how to partition your language -- i.e.: usually just separating code from comments from strings -- and specifying the keywords you have in the partition would already give you proper syntax highlighting).
If you download it, there are a number of examples at plugins\com.brainwy.liclipse.editor\languages and there's some basic documentation at http://brainwy.github.io/liclipse/supported_languages.html and http://brainwy.github.io/liclipse/scope_definition.html on how to do it.

Answer 3

For anyone coming across this as I did:
My solution involved adding the following lines into the Constructor of my Editor
Activator.getActivator().getPreferenceStore().addPropertyChangeListener(new IPropertyChangeListener() {
#Override
public void propertyChange(PropertyChangeEvent event) {
getSourceViewer().invalidateTextPresentation();
handlePreferenceStoreChanged(event);
}
});
and then creating a custom class that extended IToken. In the constructor I pass the String of the preference field and then in the 'getObject' method I create the TextAttribute: snippets below
public class MyToken extends Token implements IToken {
public MyToken(Object data) {
super(data);
}
#Override
public Object getData() {
String dataString = (String) super.getData();
return getAttributeFromColorName(dataString);
}
private TextAttribute getAttributeFromColorName(String preferenceField) {
Color color = new Color(Display.getCurrent(), StringConverter.asRGB(Activator.getActivator().getPreferenceStore().getString(preferenceField)));
return new TextAttribute(color);
}
}
When I generate my Rules I have all of my tokens as my custom class and this allowed me to change syntax color dynamically.

Answer 4

I also added an example for updating the coloring if the preference changes to https://www.vogella.com/tutorials/EclipseEditors/article.html#exercise-allow-user-to-customize-the-colors
This is using the Generic editor (currently the best approach to implement a customer editor) but it should be possible to adjust this to any Eclipse editor implementation.