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
{
			btnDel.setEnabled( true );
			if ( btnEdit != null )
				btnEdit.setEnabled( true );
		}
		else
		{
			btnDel.setEnabled( false );
			if ( btnEdit != null )
				btnEdit.setEnabled( false );
		}
		bindingTable.getTable( ).select( selectIndex );
	}
	private ComputedColumnHandle getSelectColumnHandle( )
	{
		if ( selectedColumnName != null )
		{
			for ( int i = 0; i < bindingTable.getTable( ).getItemCount( ); i++ )
			{
				ComputedColumnHandle handle = (ComputedColumnHandle) bindingTable.getElementAt( i );
				if ( selectedColumnName.equals( handle.getName( ) ) )
				{
					return handle;
				}
			}
		}
		return null;
	}
	private void updateSelection( )
	{