Bug 166315 Combo box doesn't allow blank when set string type in parameter editor
Combo box doesn't allow blank when set string type in parameter editor Steps to reproduce: 1.New a parameter, display type is Combo Box 2.Select data type as String Expected result: "Allow blank values" is enable. Actual result: "Allow blank values" is gray and can't be checked.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
if ( oldList.length != dataSetList.size( ) )
		{
			dataSetChooser.setItems( (String[]) dataSetList.toArray( new String[]{} ) );
			if ( StringUtil.isBlank( selectedDataSetName ) )
			{
				dataSetChooser.select( 0 );
				refreshColumns( false );
			}
			else
			{
				dataSetChooser.setText( selectedDataSetName );
			}
		}
	}
	private void refreshColumns( boolean onlyFilter )
	{
		if ( columnChooser == null )
		{
			return;
		}
		if ( !onlyFilter )
		{
			DataSetHandle dataSetHandle = inputParameter.getModuleHandle( )
					.findDataSet( dataSetChooser.getText( ) );
			try
			{
				columnList = DataUtil.getColumnList( dataSetHandle );
			}
			catch ( SemanticException e )
			{