Bug 166015 Refactor designer actions to eclipse command framework
Eclipse command framework provide a more explicit way to manage UI actions contributions, we can take it's advantage to make our actions code more clean and maintainable.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/editors/schematic/actions/AddStyleAction.java
public AddStyleAction( IWorkbenchPart part )
	{
		super( part );
		setId( ID );
		setText( ACTION_MSG_ADD_STYLE_RULE );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.gef.ui.actions.WorkbenchPartAction#calculateEnabled()
	 */
	protected boolean calculateEnabled( )
	{
		return true;
	}
	/**
	 * Runs action.
	 * 
	 */
	public void run( )
	{
		if ( Policy.TRACING_ACTIONS )
		{
			System.out.println( "Add Style rule action >> Run ..." ); 
		}
		CommandStack stack = getActiveCommandStack( );
		stack.startTrans( STACK_MSG_ADD_STYLE );
		ModuleHandle reportDesignHandle = SessionHandleAdapter.getInstance( )
				.getReportDesignHandle( );