DListView_Column:SetWidth
Example
Creates a DListView and populates it with two columns and two items, only one of which can be selected at a time.
The first column width is 15. The second column width is 350.
Output: 
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Creates a DListView and populates it with two columns and two items, only one of which can be selected at a time.
The first column width is 15. The second column width is 350.