Bug 165677 folder is not opened by double click
Data explorer pane contains following tree: + Data Sources - Postgres + Data Sets - Header DS - Chart DS + Report Parameters - Id It is common then if you double click on menu item, that is folder for other menu items (submenu), that it is opened. But in BIRT I can click to Data Sources (Data Sets, Report Params) as many times as I want but it never opens the submenu. In other words, when I doubleclick Data Sets, I want to open it and see which data sets are defined.
UI/org.eclipse.birt.report.designer.ui.editors/src/org/eclipse/birt/report/designer/internal/ui/views/data/DataViewTreeViewerPage.java
dropListener.addDropConstraint( CascadingParameterGroupHandle.class,
				new IDropConstraint( ) {
					public int validate( Object transfer, Object target )
					{
						return RESULT_NO;
					}
				} );
		
		
		dropListener.addDropConstraint( ScalarParameterHandle.class,
				new IDropConstraint( ) {
					public int validate( Object transfer, Object target )
					{
						if ( target instanceof ScalarParameterHandle )
						{
							ScalarParameterHandle targetParameter = (ScalarParameterHandle) target;
							if ( targetParameter.getContainer( ) instanceof CascadingParameterGroupHandle )
								return RESULT_NO;
						}
						return RESULT_UNKNOW;
					}
				} );
		
		IDropConstraint cascadingParameterGroupChildrenConstraint = new IDropConstraint( ) {
			public int validate( Object transfer, Object target )
			{
				if ( transfer instanceof Object[]
						&& ( (Object[]) transfer ).length > 0
						&& ( (Object[]) transfer )[0] instanceof ScalarParameterHandle )
				{