Bug 198504 The same name aggregation should be hint in dialog[0001]
Description: The same name aggregation should be hint in dialog[0001] Step: 1.New a datasource, dataset, table and binding the dataset. 2.New a aggregation column binding on table named aggr1. 3.Drop a aggregation item into table and set the named as aggr1. 4.Click OK Actual result: Pop up an error message said that the name is exist. Expected result: It can hint in dialog when input the same name, but pop up an error dialog
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dialogs/BindingDialogHelper.java
ExpressionBuilder expression = new ExpressionBuilder( combo.getText( ) );
				expression.setExpressionProvier( expressionProvider );
				if ( expression.open( ) == Window.OK )
				{
					if ( expression.getResult( ) != null )
						combo.setText( expression.getResult( ) );
				}
			}
		} );
	}
	protected void setExpressionButtonImage( Button button )
	{
		String imageName;
		if ( button.isEnabled( ) )
		{
			imageName = IReportGraphicConstants.ICON_ENABLE_EXPRESSION_BUILDERS;
		}
		else
		{
			imageName = IReportGraphicConstants.ICON_DISABLE_EXPRESSION_BUILDERS;
		}
		Image image = ReportPlatformUIImages.getImage( imageName );
		GridData gd = new GridData( );
		gd.widthHint = 20;
		gd.heightHint = 20;
		button.setLayoutData( gd );
		button.setImage( image );
		if ( button.getImage( ) != null )
		{
			button.getImage( ).setBackground( button.getBackground( ) );