Disabling a particular row in list in thingworx

Hi,

I am trying to disable selection of a particular row in list widget(drop down) This option is not dependent on any functionality. That particular field should always be present on drop down menu but it should be unselectable.

Similarly, I am also trying to disable selection of a particular row in advanced grid.That particular field should always be present in advanced grid but it should be unselectable. 

Any lead on this is appreciable.

Regards,

MishiK