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Query#:- But when i add dropdownbutton using ng-template for each row than it make my page unresponsive.
We can reproduce the reported problem at our end. While using large number of records with Template column, it will take time to render cell with Templates while on rendering TreeGrid. To overcome this problem, we suggest you enable Paging for TreeGrid. Please find the below sample link
Could you please check the above sample, If the above solution doesn’t meet your requirement, Share us the purpose of rendering the large number records in single Page.