Bug 180864 Change Allow Null option in Cascading Group.[0705]
Description: Change Allow Null option in Cascading Group. Build number:2.2.0.v20070404 Steps to reproduce: 1. New a cascading group and add sub parameter. Expected result: Is Required option in cascading group definition dialog. Actual result: Allow null value option in Cascading Group definition dialog Error log:N/A
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/CascadingParametersDialog.java
}
	/*
	 * set input for dialog
	 */
	public void setInput( Object input )
	{
		Assert.isNotNull( input );
		Assert.isLegal( input instanceof CascadingParameterGroupHandle );
		inputParameterGroup = (CascadingParameterGroupHandle) input;
	}
	
	protected boolean initDialog( )
	{
		cascadingNameEditor.setText( inputParameterGroup.getName( ) );
		promptTextEditor.setText( UIUtil.convertToGUIString( inputParameterGroup.getPromptText( ) ) );
		if ( DesignChoiceConstants.DATA_SET_MODE_MULTIPLE.equals( inputParameterGroup.getDataSetMode( ) ) )
		{
			multiDataSet.setSelection( true );
		}
		else
		{
			singleDataSet.setSelection( true );
		}
		valueTable.setInput( inputParameterGroup );
		refreshParameterProperties( );
		updateButtons( );
		return true;
	}
	
	protected void okPressed( )