I have a gallery that lists all the items, this can be filtered by date created with to and from range and then exported to CSV, At the moment the user need to tick each checkbox, but I'd like to add a select all button that would only select those visible from the filtered option.
Gallery Items
Sort(Filter(
colDWB,
(Due_x0020_Date >= DatePicker1.SelectedDate) && (Due_x0020_Date <= DatePicker2.SelectedDate)), ID, Descending)
Refresh button - OnSelect
ClearCollect(colDWB, AddColumns('Dont Walk By', "IsChosen", false))
Export to CSV button
Set(varDrop, DropColumns(Filter(colDWB, IsChosen), "Author", "Assigned_x0020_to", "Category", "Editor", "Manager", "Priority", "joim" , "{Thumbnail}", "Related_x0020_Issues"));
Set(varFormattedJSON, JSON(varDrop, JSONFormat.IndentFour));
ExportToCSV_Email.Run(varFormattedJSON)
OnCheck on checkbox
Patch(colDWB, ThisItem, {IsChosen: true})
OnUncheck of checkbox
Patch(colDWB, ThisItem, {IsChosen: false})
This works great each item that ticked can then be exported, but id like to add a select all option

Not sure who to do this without removing my already working and required export function.