Bug 155365 Can not set data type to "date time" when editing "Data Item"
Description: Can not set data type to "date time" when editing "Data Item" Steps to reproduce: 1. Insert a data item to the layout 2. Name it and set the expression to "a = new Date()" 3. Select the data type to date time 4. Press ok Actual result: An Birt Exception is thrown out. Expected result: No NPE thrown out
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ColumnBindingDialog.java
private static final String[] dataTypeDisplayNames = ChoiceSetFactory.getDisplayNamefromChoiceSet( DATA_TYPE_CHOICE_SET );
	private boolean canSelect = false;
	protected ReportItemHandle inputElement;
	
	
	private TableViewer bindingTable;
	private ExpressionCellEditor expressionCellEditor;
	private String selectedColumnName = null;
	private String NullChoice = null;
	private int selectIndex;
	private IStructuredContentProvider contentProvider = new IStructuredContentProvider( ) {
		public void dispose( )
		{
		}
		public void inputChanged( Viewer viewer, Object oldInput,
				Object newInput )
		{
		}
		public Object[] getElements( Object inputElement )
		{
			List elementsList = getBindingList( (DesignElementHandle) inputElement );
			
			return elementsList.toArray( );
		}
	};
	private ITableLabelProvider labelProvider = new ITableLabelProvider( ) {
		public Image getColumnImage( Object element, int columnIndex )
		{
			return null;
		}