Description Damian Biollo 2007-04-26 17:00:03 EDT

I think a few small changes to the StatusLineManager and the StatusLine classes would make it much easier to customize (instead of re-write) the status bar in RCP applications.

In my app, everything about the status bar is fine, except that I need to tweak the layout manager (for example, to make the message label smaller and another control bigger). Simply applying a new layout (such as RowLayout) to the existing StatusLine control doesn't quite work because their are some internal state variables in StatusLine (such as fProgressIsVisible and fCancelButtonIsVisible) which are required to correctly show or hide controls.

The other issue is with StatusLineManager, which makes it impossible to override createControl without re-implementing the entire class. The internal member "statusLine" is declared private and there is no way to assign it from a subclass.

As it is right now, I need to make a duplicate copy of both classes in order to make a small tweak to the layout. 


For my scenario, two simple changes would be sufficient to improve the extensibility of the status bar:

1. Make StatusLine public. Currently it is package protected.
2. Add a protected function createStatusLine to StatusLineManager and call it from createControl:

    public Control createControl(Composite parent, int style) {
        if (!statusLineExist() && parent != null) {
            statusLine = createStatusLine ();
            update(false);
        }
        return statusLine;
    }

protected StatusLine createStatusLine () {
   return new StatusLine(parent, style);
}


This would allow one to provide a subclass of StatusLine as the implementation control.