iOS 13.5.1: UIActivityViewController not showing on iPad

The following code works fine on an iPhone on iOS 13.5.1 and an iPad on iOS 12.4.7, but nothing happens when it's triggered on an iPad on iOS 13.5.1:

- (void)notificationFired:(NSNotification *)notification {
    if (notification != (id)[NSNull null] && [[notification name] isEqualToString:@"OpenActionSheet"]) {
        NSString *path = [notification userInfo][@"path"];
        
        printf("Received path: %s", path.UTF8String);

        NSURL *url = [NSURL fileURLWithPath:path];
        
        UIActivityViewController *controller = [[UIActivityViewController alloc] initWithActivityItems:@[url] applicationActivities:nil];
        [controller setCompletionWithItemsHandler:^(NSString *activityType, BOOL completed, NSArray *returnedItems, NSError *activityError) {
            printf("%s", "Share sheet closed");
            UnitySendMessage("ShareListener", "Complete", path.UTF8String);
        }];
        
        if (IDIOM == IPAD)
            controller.modalPresentationStyle = UIModalPresentationPopover

        [self.window.rootViewController presentViewController:controller animated:YES completion:nil];
        
        if (IDIOM == IPAD) {
            UIPopoverPresentationController *popover = controller.popoverPresentationController;
            popover.sourceView = self.window.rootViewController.view;
        }
    }
}

I've also tried

if ([controller respondsToSelector:@selector(popoverPresentationController)])
    controller.popoverPresentationController.sourceView = self.rootView;
        
[self.window.rootViewController presentViewController:controller animated:YES completion:nil];

instead of the IDIOM == IPAD blocks, but that has the same results. What am I missing?

Solution

Instead of just assigning sourceView, you should also assigning sourceRect

popover.sourceRect = CGRectMake(0, 0, 100, 100) // change the rect to the frame you want the view to appear

I hope it'll fix your problem. Tested in iPad Pro (12.9-inch) (4th generation) XCode 11.5.