UIAlertControllerのアクションをどのように処理するのですか？

Question

objective-cを使用してUIAlertController警告アクションボタンとアクションハンドラをリンクするにはどうすればよいですか？私はXcode 7.1を使用しています。私はあなたがそれを意味だと思う

UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"Title" message:@"text mssg" preferredStyle:UIAlertControllerStyleAlert]; 
UIAlertAction *okAction = [UIAlertAction actionWithTitle:@"Ok" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action){ 
    // Ok action example 
}]; 
UIAlertAction *otherAction = [UIAlertAction actionWithTitle:@"Other" style:UIAlertActionStyleDefault handler:^(UIAlertAction * action){ 
    // Other action 
}]; 
[alert addAction:okAction]; 
[alert addAction:otherAction]; 
[self presentViewController:alert animated:YES completion:nil]; 

：

- (IBAction)selectbtn:(UIButton *)sender { 

    UIAlertController *alert=[ UIAlertController alertControllerWithTitle:@"NEW" message:@"button pressed" preferredStyle:UIAlertControllerStyleActionSheet]; 
    UIAlertAction *cameraaction=[UIAlertAction actionWithTitle:@"From camera" style:UIAlertActionStyleDefault handler:nil ]; 
    [alert addAction:cameraaction]; 
    UIAlertAction *libraryaction=[UIAlertAction actionWithTitle:@"From photo library" style:UIAlertActionStyleDefault handler:nil ]; 
    [alert addAction:libraryaction]; 
    UIAlertAction *cancelaction=[UIAlertAction actionWithTitle:@"cancel" style:UIAlertActionStyleDestructive handler:nil]; 
    [alert addAction:cancelaction]; 
    [self presentViewController:alert animated:YES 
        completion:nil]; 
    } 

Answer 1

のObjective-Cこのように動作しますUIAlertController

：

は、ここに私のコードです。

スウィフト3.0/4.0

let myalert = UIAlertController(title: "Titulo mensaje", message: "Mi mensaje.", preferredStyle: UIAlertControllerStyle.alert) 

myalert.addAction(UIAlertAction(title: "Aceptar", style: .default) { (action:UIAlertAction!) in 
     print("Selected") 
    }) 
myalert.addAction(UIAlertAction(title: "Cancelar", style: .cancel) { (action:UIAlertAction!) in 
     print("Cancel") 
    }) 

    self.present(myalert, animated: true) 

Answer 2

あなたは、サンプルコードは、このようにすることができ、あなたはアクションメソッドのハンドラにしたい任意のコードを追加することができます

@interface ViewController() <UIImagePickerControllerDelegate, UINavigationControllerDelegate> 
@property (weak, nonatomic) IBOutlet UIImageView *imageView; 
@property (strong, nonatomic) UIAlertController *alertCtrl; 
@property (strong, nonatomic) UIImagePickerController *imagePicker; 
@end 

@implementation ViewController 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    [self setupAlertCtrl]; 
} 

- (void) setupAlertCtrl 
{ 
    self.alertCtrl = [UIAlertController alertControllerWithTitle:@"Select Image" 
                 message:nil 
                preferredStyle:UIAlertControllerStyleActionSheet]; 
    //Create an action 
    UIAlertAction *camera = [UIAlertAction actionWithTitle:@"From camera" 
                style:UIAlertActionStyleDefault 
                handler:^(UIAlertAction *action) 
                { 
                 [self handleCamera]; 
                }]; 
    UIAlertAction *imageGallery = [UIAlertAction actionWithTitle:@"From Photo Library" 
                style:UIAlertActionStyleDefault 
                handler:^(UIAlertAction *action) 
                { 
                 [self handleImageGallery]; 
                }]; 
    UIAlertAction *cancel = [UIAlertAction actionWithTitle:@"Cancel" 
                  style:UIAlertActionStyleCancel 
                 handler:^(UIAlertAction *action) 
            { 
             [self dismissViewControllerAnimated:YES completion:nil]; 
            }]; 


    //Add action to alertCtrl 
    [self.alertCtrl addAction:camera]; 
    [self.alertCtrl addAction:imageGallery]; 
    [self.alertCtrl addAction:cancel]; 


} 

- (IBAction)selectImagePressed:(UIButton *)sender 
{ 
    [self presentViewController:self.alertCtrl animated:YES completion:nil]; 
} 

- (void)handleCamera 
{ 
#if TARGET_IPHONE_SIMULATOR 
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"Error" 
                    message:@"Camera is not available on simulator" 
                  preferredStyle:UIAlertControllerStyleAlert]; 

    UIAlertAction *ok = [UIAlertAction actionWithTitle:@"OK" 
               style:UIAlertActionStyleDefault 
               handler:^(UIAlertAction *action) 
               { 
                [self dismissViewControllerAnimated:YES completion:nil]; 
               }]; 

    [alert addAction:ok]; 
    [self presentViewController:alert animated:YES completion:nil]; 
#elif TARGET_OS_IPHONE 
    //Some code for iPhone 
    self.imagePicker = [[UIImagePickerController alloc] init]; 
    self.imagePicker.delegate = self; 
    self.imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera; 
    [self presentViewController:self.imagePicker animated:YES completion:nil]; 

#endif 
} 

- (void)handleImageGallery 
{ 
    self.imagePicker = [[UIImagePickerController alloc] init]; 
    self.imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary; 
    self.imagePicker.delegate = self; 
    [self presentViewController:self.imagePicker animated:YES completion:nil]; 
} 

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info 
{ 
    NSData *dataImage = UIImageJPEGRepresentation([info objectForKey:@"UIImagePickerControllerOriginalImage"],1); 
    UIImage *img = [[UIImage alloc] initWithData:dataImage]; 
    [self.imageView setImage:img]; 
    [self.imagePicker dismissViewControllerAnimated:YES completion:nil]; 

} 

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