It's not clear to me why the column headers disappear when the view bar is hidden.
Also, the sort utility seems a bit out of place in the view bar since all the other items are filters. Perhaps a better way would be to implement sorting by clicking on the column headers. Not only would that be a bit more of a standard approach, but it would allow for sort direction to be toggled (like Finder windows in list mode). Ideally, the user would be able to specify which columns appear in the view and drag them to arrange their order.
Also, the sort utility seems a bit out of place in the view bar since all the other items are filters. Perhaps a better way would be to implement sorting by clicking on the column headers. Not only would that be a bit more of a standard approach, but it would allow for sort direction to be toggled (like Finder windows in list mode). Ideally, the user would be able to specify which columns appear in the view and drag them to arrange their order.
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