GridView containing Cards doesn’t calculate height correctly.
Your problem is that the tiles of GridView.count have a default aspect ratio of 1.0 (i.e. square), and it sounds like you want your tiles to be shorter than that.
A quick fix would be to hard code the childAspectRatio to a number you like. A more nuanced approach would be to implement a SliverGridDelegate that describes the layout you want and use GridView.custom. You could also just do a ListView of 2-element Row widgets and not use GridView at all.
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