问题
I created a popup alert using alert controller and added two alert actions(ok and cancel) as below.
UIAlertController * alert= [UIAlertController
alertControllerWithTitle:@"Cycling"
message:@"Please enter title and description"
preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction* ok = [UIAlertAction
actionWithTitle:@"OK"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action)
{
[alert dismissViewControllerAnimated:YES completion:nil];
}];
UIAlertAction* cancel = [UIAlertAction
actionWithTitle:@"Cancel"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction * action)
{
[alert dismissViewControllerAnimated:YES completion:nil];
}];
[alert addAction:ok];
[alert addAction:cancel];
[self presentViewController:alert animated:YES completion:nil];
Now, i want add UITextView. Because I have two text field like title and description. For description i want to use UITextView for adding no.of lines. I tried i am not getting how to add it.
Please advice.
回答1:
Adding UITextView to UIAlertController:
https://gist.github.com/bennagar/c0cd618bcd23c4c2dadf
func showAlert() {
let saveAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
saveAction.enabled = false
let cancelAction = UIAlertAction(title: "Cancel", style: .Cancel, handler: nil)
alertController.view.addObserver(self, forKeyPath: "bounds", options: NSKeyValueObservingOptions.New, context: nil)
NSNotificationCenter.defaultCenter().addObserverForName(UITextViewTextDidChangeNotification, object: textView, queue: NSOperationQueue.mainQueue()) { (notification) in
saveAction.enabled = self.textView.text != ""
}
textView.backgroundColor = UIColor.greenColor()
alertController.view.addSubview(self.textView)
alertController.addAction(saveAction)
alertController.addAction(cancelAction)
self.presentViewController(alertController, animated: true, completion: nil)
}
override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer<Void>) {
if keyPath == "bounds"{
if let rect = (change?[NSKeyValueChangeNewKey] as? NSValue)?.CGRectValue(){
let margin:CGFloat = 8.0
textView.frame = CGRectMake(rect.origin.x + margin, rect.origin.y + margin, CGRectGetWidth(rect) - 2*margin, CGRectGetHeight(rect) / 2)
textView.bounds = CGRectMake(rect.origin.x + margin, rect.origin.y + margin, CGRectGetWidth(rect) - 2*margin, CGRectGetHeight(rect) / 2)
}
}
}
<script src="https://gist.github.com/bennagar/c0cd618bcd23c4c2dadf.js"></script>Still locking for way to get the height of the marked view, when I have it I can just replace the /2 with the correct height.
回答2:
With the above solutions my textview was not positioned correctly. This is how I got it to work:
// The \n is required so that the alertcontroller keeps space for the message. Add as many \n as you like your textview height to be
self.alertController = [UIAlertController alertControllerWithTitle:@"Some title"
message:@"\n\n\n\n\n\n\n\n"
preferredStyle:UIAlertControllerStyleAlert];
self.alertController.view.autoresizesSubviews = YES;
UITextView *textView = [[UITextView alloc] initWithFrame:CGRectZero];
textView.translatesAutoresizingMaskIntoConstraints = NO;
textView.editable = NO;
textView.dataDetectorTypes = UIDataDetectorTypeAll;
textView.text = @"Some really long text here";
textView.userInteractionEnabled = YES;
textView.backgroundColor = [UIColor clearColor];
// This will make the scroll view scrollable if the text is too long
textView.scrollEnabled = YES;
NSLayoutConstraint *leadConstraint = [NSLayoutConstraint constraintWithItem:self.alertController.view attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:textView attribute:NSLayoutAttributeLeading multiplier:1.0 constant:-8.0];
NSLayoutConstraint *trailConstraint = [NSLayoutConstraint constraintWithItem:self.alertController.view attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:textView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:8.0];
NSLayoutConstraint *topConstraint = [NSLayoutConstraint constraintWithItem:self.alertController.view attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:textView attribute:NSLayoutAttributeTop multiplier:1.0 constant:-64.0];
NSLayoutConstraint *bottomConstraint = [NSLayoutConstraint constraintWithItem:self.alertController.view attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:textView attribute:NSLayoutAttributeBottom multiplier:1.0 constant:64.0];
[self.retailerHelpAlertController.view addSubview:textView];
[NSLayoutConstraint activateConstraints:@[leadConstraint, trailConstraint, topConstraint, bottomConstraint]];
回答3:
Fantastic solutions above. Some needed some manipulation to work for Swift 4.2, here is the conversion for that. I've also added some padding in the TextView to make it athletically more pleasing.
let textView = UITextView(frame: CGRect.zero)
@IBAction func alert(_ sender: Any) {
let alertController = UIAlertController(title: "\n\n\n\n\n", message: nil, preferredStyle: .alert)
textView.textContainerInset = UIEdgeInsets.init(top: 8, left: 5, bottom: 8, right: 5)
let saveAction = UIAlertAction(title: "OK", style: .default) { (action) in
self.label.text = self.textView.text
alertController.view.removeObserver(self, forKeyPath: "bounds")
}
saveAction.isEnabled = false
let cancelAction = UIAlertAction.init(title: "Cancel", style: .default) { (action) in
alertController.view.removeObserver(self, forKeyPath: "bounds")
}
alertController.view.addObserver(self, forKeyPath: "bounds", options: NSKeyValueObservingOptions.new, context: nil)
NotificationCenter.default.addObserver(forName: UITextView.textDidChangeNotification, object: textView, queue: OperationQueue.main) { (notification) in
saveAction.isEnabled = self.textView.text != ""
}
textView.backgroundColor = UIColor.white
alertController.view.addSubview(self.textView)
alertController.addAction(saveAction)
alertController.addAction(cancelAction)
self.present(alertController, animated: true, completion: nil)
}
override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
if keyPath == "bounds"{
if let rect = (change?[NSKeyValueChangeKey.newKey] as? NSValue)?.cgRectValue {
let margin:CGFloat = 8.0
textView.frame = CGRect.init(x: rect.origin.x + margin, y: rect.origin.y + margin, width: rect.width - 2*margin, height: rect.height / 2)
textView.bounds = CGRect.init(x: rect.origin.x + margin, y: rect.origin.y + margin, width: rect.width - 2*margin, height: rect.height / 2)
}
}
}
回答4:
Swift 3
let alert = UIAlertController(title: nil, message: nil, preferredStyle: .alert)
let textView = UITextView()
textView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
let controller = UIViewController()
textView.frame = controller.view.frame
controller.view.addSubview(textView)
alert.setValue(controller, forKey: "contentViewController")
let height: NSLayoutConstraint = NSLayoutConstraint(item: alert.view, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: view.frame.height * 0.8)
alert.view.addConstraint(height)
present(alert, animated: true, completion: nil)
回答5:
Johno2110's solution worked best for me with a little cleanup and tweaking. Posting the code and a screenshot of the result here in case it helps anybody else out.
Confirmed working with Swift 5.
let textView = UITextView(frame: CGRect.zero)
@IBAction func sendFeedback(_ sender: Any) {
let alertController = UIAlertController(title: "Feedback \n\n\n\n\n", message: nil, preferredStyle: .alert)
let cancelAction = UIAlertAction.init(title: "Cancel", style: .default) { (action) in
alertController.view.removeObserver(self, forKeyPath: "bounds")
}
alertController.addAction(cancelAction)
let saveAction = UIAlertAction(title: "Submit", style: .default) { (action) in
let enteredText = self.textView.text
alertController.view.removeObserver(self, forKeyPath: "bounds")
}
alertController.addAction(saveAction)
alertController.view.addObserver(self, forKeyPath: "bounds", options: NSKeyValueObservingOptions.new, context: nil)
textView.backgroundColor = UIColor.white
textView.textContainerInset = UIEdgeInsets.init(top: 8, left: 5, bottom: 8, right: 5)
alertController.view.addSubview(self.textView)
self.present(alertController, animated: true, completion: nil)
}
override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
if keyPath == "bounds"{
if let rect = (change?[NSKeyValueChangeKey.newKey] as? NSValue)?.cgRectValue {
let margin: CGFloat = 8
let xPos = rect.origin.x + margin
let yPos = rect.origin.y + 54
let width = rect.width - 2 * margin
let height: CGFloat = 90
textView.frame = CGRect.init(x: xPos, y: yPos, width: width, height: height)
}
}
}
回答6:
Try this code I got from here: http://useyourloaf.com/blog/2014/09/05/uialertcontroller-changes-in-ios-8.html
UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"Title", message:@"Message", preferredStyle:UIAlertControllerStyleAlert];
[alertController addTextFieldWithConfigurationHandler:^(UITextField *textField) {
textField.placeholder = NSLocalizedString(@"LoginPlaceholder", @"Login");
}];
Then show it.
来源：https://stackoverflow.com/questions/28603060/how-to-use-uitextview-in-uialertcontroller