         let alert = UIAlertController(
             title: "Size",
             message: nil,
-            preferredStyle: .alert
+            preferredStyle: .actionSheet
         )
         alert.addAction(
             UIAlertAction(title: "Cancel", style: .cancel, handler: {

        let alert = UIAlertController(
            title: "FrontColor",
            message: nil,
            preferredStyle: .alert
        )
        alert.addAction(
            UIAlertAction(title: "Cancel", style: .cancel, handler: {

            ) {
            self.present(ShowController(image: tryImage), animated: true, completion: nil)
        } else {
            let alert = UIAlertController(title: "Warning", message: "Create QRCode failed!", preferredStyle: .actionSheet)
            alert.addAction(UIAlertAction(title: "OK", style: .cancel, handler: nil))
            self.present(alert, animated: true, completion: nil)
        }
