[news.eclipse.platform] Properties View should listen to model changes

[Kai <yavin@xxxxxxx>]

Hello everybody,

we develop an application with a 3D render view which raises almost
continous changes of the data model, e.g. the user moves the camera to
inspect the scene. Since the properties view only reacts on selection
changes, we never saw a change in the cameras position property. First I
thought we do something wrong but the matter is that we are firing an
element change event, not a selection change event.

I tested the behavior with a simple text file. Created a new one and
looked at the size property: 0kb. Okay I typed something and saved the
file but the properties didn't update until I selected the file in the
Resource navigator. IMHO this is irritating for a user who expects that
the size of the file changes even after he saved it.

This leads me to the proposal to define an extension point for custom
PropertySheetPages or an extension of the IPropertySource extension
point. In case of an extension of the IPropertySource the interface
needs API to give the PropertySheetPage the possibility to register with
the models element change events.

interface ISourceChangedListener {
  void sourceChanged();
}

interface IPropertySource {
  void addSourceChangedListener(ISourceChangedListener  listener);
  void removeSourceChangedListener(ISourceChangedListener listener);
}

class PropertySheetPage implements ISourceChangedListener {
  void sourceChanged()
  {
    //do necessary steps to update the view
  }
}

Is this the right place to discuss such proposals?
Regards, Kai