Swift: Getting 'Snapshotting a view that has not been rendered..' error when trying to open a URL in safari from my app

Question

One of the specifications of my app is that on tapping a tableView cell, the user will be redirected to the website associated with the cell. Here is the code:

Answer 1

It might not be the same problem as me, but I just solved the same warning in my logs.

I'm showing a UIAlertController as an actionSheet popover on an iPad, and I had exactly the same warning 8 times in a row every time I tried to show the alert controller.

To make the warning disappear all I had to do was to layout the alert controller view as in the following code:

let alertController = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)

    ...            

alertController.view.layoutIfNeeded() //avoid Snapshotting error
self.presentViewController(alertController, animated: true, completion: nil)

I hope this helps you or any other person having the same warning.

Answer 2

I'm triggering a UIAlertControllerStyleActionSheet UIAlertController after the user clicks a UITableViewRowAction, and I got the same error message repeated 8 times after presenting the UIAlertController.

On the iPad Pro Simulator for iOS 9.3, I tried Saliom's answer, and I went from eight log messages to one.

As anorskdev suggested, I put my call to -[UIView layoutIfNeeded] after my -[UIViewController presentViewController:animated:completion:] call, and all the warnings disappeared:

- (NSArray<UITableViewRowAction *> *)tableView:(UITableView *)tableView editActionsForRowAtIndexPath:(NSIndexPath *)indexPath
{
  UITableViewRowAction *moreAction =
  [UITableViewRowAction rowActionWithStyle:UITableViewRowActionStyleDefault
                                     title:@"More"
                                   handler:^(UITableViewRowAction * _Nonnull action,
                                             NSIndexPath * _Nonnull moreIndexPath)
  {
    UIAlertController *alertController = 
    [UIAlertController alertControllerWithTitle:name 
                                        message:nil
                                 preferredStyle:UIAlertControllerStyleActionSheet];
    UIAlertAction *deleteAlertAction = 
    [UIAlertAction actionWithTitle:@"Delete"
                             style:UIAlertActionStyleDestructive
                           handler:deleteAction];
    [alertController addAction:deleteAlertAction];

    UIAlertAction *cancelAlertAction = 
    [UIAlertAction actionWithTitle:@"Cancel"
                             // totally ok to use the proper
                             // UIAlertActionStyleCancel
                             style:UIAlertActionStyleCancel
                           handler:cancelAction];
    [alertController addAction:cancelAlertAction];

    CGRect sourceRect = [self.tableView rectForRowAtIndexPath:moreIndexPath];

    // You must specify a sourceRect and sourceView
    // or a barButtonItem or presenting a
    // UIAlertControllerStyleActionSheet UIAlertController
    // will crash on iPad.
    alertController.popoverPresentationController.sourceRect = sourceRect;
    alertController.popoverPresentationController.sourceView = self.tableView;
    // first, present the alertController
    [self presentViewController:alertController
                       animated:YES
                     completion:nil];
    // then -layoutIfNeeded
    [alertController.view layoutIfNeeded];
  }
  return @[
          moreAction,
          ];
}

Notice that it wasn't necessary to use Patrick's solution of using UIAlertActionStyleDefault for cancelAlertAction or nurider's solution of eliminating it altogether on iPads.