In an Windows Forms app you can customize SaveFileDialog with checkboxes and buttons etc
How can I do the same with the FileSavePicker in an UWP app? Is there any way to add custom UI controls to the FileSavePicker dialog?
FilePicker does have some options to add file type filters and customize its options : https://learn.microsoft.com/en-us/uwp/api/windows.storage.pickers.filesavepicker
but it does not provide a way to actually change its UI o some deep customization, but if you really want this feature in a future SDK you can request for it on uservoice : https://wpdev.uservoice.com/forums/110705-universal-windows-platform
FilePicker does have some options to add file type filters and customize its options : https://learn.microsoft.com/en-us/uwp/api/windows.storage.pickers.filesavepicker
but it does not provide a way to actually change its UI o some deep customization, but if you really want this feature in a future SDK you can request for it on uservoice : https://wpdev.uservoice.com/forums/110705-universal-windows-platform