Adding new datasource to existed form and linking with other data source

final class CITEcoResProductDetailsExtended_Extension
{

Created a view "ProductCategoryView"  and added link to existing data source using code.


    public void init()
    {
        QueryBuildDataSource  queryDataSourceLink;
        next init();   
        queryDataSourceLink  = this.query().datasourcetable(tablenum(ProductCategoryView));
        queryDataSourceLink.addlink(fieldNum(EcoResProductCategory,Category),fieldnum(ProductCategoryView,ChildRecId)); 
    }

}