When scrolling down, the GridCellNumericRenderer will never called. The "ReadOnly" formatted cells there are only "a copy of the first cells" but do not match to the "ReadOnly" information in the corresponding column.
JGJai Ganesh S Syncfusion Team January 5, 2017 06:30 PM UTC
We have analyzed your query with your sample. In that you have displayed the disabled cells through OnInitializeDisplayElement of GridCellNumericRenderer and also you have applied the disabled style for TextBlock not GridCell. Hence the issues occurred. However, you can achieve this requirement by using CellTempateSelector and CurrentCelBeginEdit event. We have already prepared a sample for this in the forums #128088, #127476.