当我尝试通过我的应用程序发送短信时，消息屏幕会自动取消

Question

我要求我的应用程序接受用户输入来格式化文本消息，以便他们可以通过文本以正确的格式连接到外部设备。我有初始设置文本消息，但如果用户希望删除地理围栏(初始文本消息负责设置它(，他们需要发送不同的文本消息，但是消息屏幕在调用时会自动取消。

@IBAction func addGeoFencePushed(_ sender: Any) {
if(!geoFenceIsEnabled()){
let alertController = UIAlertController(title: nil, message: "How large would you like the geofence to be?", preferredStyle: .alert)
let confirmAction = UIAlertAction(title: "Confirm", style: .default) { (_) in
if let field = alertController.textFields?[0] {
// store your data
ALGlobal.sharedInstance.globalDefaults.set(field.text! as String, forKey: "geoFenceSize")
let rad = Double(field.text!)
ALGlobal.sharedInstance.geoFenceRadius = rad!
self.buttonSetting = 1
self.toggleButton()
self.drawGeoFence(radius: rad!)
self.turnOnFenceText(radius: Int(rad!))
} else {
// user did not fill field
}
}
let cancelAction = UIAlertAction(title: "Cancel", style: .cancel) { (_) in }
alertController.addTextField { (textField) in
textField.placeholder = "Feet"
textField.keyboardType = .numberPad
}
alertController.addAction(confirmAction)
alertController.addAction(cancelAction)
self.present(alertController, animated: true, completion: nil)
}
else{
// create the alert
let alert = UIAlertController(title: "Confirm", message: "Are you sure you want to remove the geo-fence?", preferredStyle: UIAlertControllerStyle.alert)
let confirmAction = UIAlertAction(title: "Confirm", style: .default) { (_) in
alert.dismiss(animated: true, completion: nil)
self.removeGeoFence()
}
alert.addAction(confirmAction)
alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
// show the alert
self.present(alert, animated: true, completion: nil)
}
}

这是负责确定要显示的文本消息的内容。

func removeGeoFence(){
self.turnOffFenceText()
ALGlobal.sharedInstance.globalDefaults.removeObject(forKey: "geoFenceSize")
ALGlobal.sharedInstance.geoFenceRadius = 0
self.buttonSetting = 0
self.toggleButton()
self.clearMap()
}
func turnOnFenceText(radius: Int){
let radiusConverted = Int(radius / 3)
messageVC.body = "G1,1,0,(radiusConverted)M"
messageVC.recipients = [ALGlobal.sharedInstance.globalDefaults.object(forKey: "devicePhoneNumber") as! String]
self.present(messageVC, animated: true, completion: nil)
}
func turnOffFenceText(){
messageVC.body = "G1,0"
messageVC.recipients = [ALGlobal.sharedInstance.globalDefaults.object(forKey: "devicePhoneNumber") as! String]
self.present(messageVC, animated: true, completion: nil)
}
func messageComposeViewController(_ controller: MFMessageComposeViewController, didFinishWith result: MessageComposeResult) {
switch (result.rawValue) {
case MessageComposeResult.cancelled.rawValue:
print("Message was cancelled")
messageVC.dismiss(animated: true, completion: nil)
case MessageComposeResult.failed.rawValue:
print("Message failed")
messageVC.dismiss(animated: true, completion: nil)
case MessageComposeResult.sent.rawValue:
print("Message was sent")
messageVC.dismiss(animated: true, completion: nil)
//self.dismiss(animated: true, completion: nil)
default:
break;
}
}

这些是消息控制器。当调用 removeGeoFence(( 时，控制台会打印出"消息已取消"，并且消息应用程序永远不会打开，我不知道为什么。

Answer 1

您需要在关闭消息VC后重新创建它，否则您尝试重新打开已关闭的视图并导致黑屏，因此在turnOnFenceText((和turnOffFenceText((中我重新初始化了消息VC：

func turnOnFenceText(radius: Int){
messageVC = MFMessageComposeViewController()
messageVC.messageComposeDelegate = self;
let radiusConverted = Int(radius / 3)
messageVC.body = "G1,1,0,(radiusConverted)M"
messageVC.recipients = [ALGlobal.sharedInstance.globalDefaults.object(forKey: "devicePhoneNumber") as! String]
self.present(messageVC, animated: true, completion: nil)
}
func turnOffFenceText(){
messageVC = MFMessageComposeViewController()
messageVC.messageComposeDelegate = self;
messageVC.body = "G1,0"
messageVC.recipients = [ALGlobal.sharedInstance.globalDefaults.object(forKey: "devicePhoneNumber") as! String]
self.present(messageVC, animated: true, completion: nil)
}

解决了问题