WPF DataTrigger to display and hide grid column XAML

Question

I have an WPF application that contains a grid. The grid is split into 3 columns with the 3rd grid having zero width upon loading.

I have two datagrids in the other two

Answer 1

Using the correct DataTrigger, this is totally possible. First, add the Trigger to the UI element that you want to change... the ColumnDefinition, not the Grid:

Next, don't set the Width on the ColumnDefinition element, but in the Style instead. Otherwise the Width on the ColumnDefinition element will override the value set from the DataTrigger.