从AlertController文本字段获取字符串时出错

Question

I need to get the text from a textfield in an alertcontroller as an NSString, but when i try to return something i get the error "Incompatible block pointer types sending NSString"

I can get the value and make it show in the NSLog within the handler, but not outside of it.

    UIAlertAction *enterAction = [UIAlertAction
                              actionWithTitle:@"Enter"
                              style:UIAlertActionStyleDefault
                              handler:^(UIAlertAction *action) {
                                  NSLog(@"Enter Action");
                                  NSString *name = ((UITextField *)[alertController.textFields objectAtIndex:0]).text;
                                  NSString *time = ((UITextField *)[alertController.textFields objectAtIndex:1]).text;
                                  [alertController dismissViewControllerAnimated:YES completion:nil];
                                  NSLog(@"%@", name);
                                  NSLog(@"%@", time);
                                  return name;
                              }];

The full piece of code is here

- (void)textPopUp{

    UIAlertController * alertController = [UIAlertController
                                       alertControllerWithTitle:@"Attention!"
                                       message:@"Please enter project name, and time spent below"
                                       preferredStyle:UIAlertControllerStyleAlert];

    UIAlertAction *cancelAction = [UIAlertAction
                               actionWithTitle:@"Cancel"
                               style:UIAlertActionStyleCancel
                               handler:^(UIAlertAction *action){
                                   [alertController dismissViewControllerAnimated:YES completion:nil];
                                   NSLog(@"Cancel Action");
                               }];

    UIAlertAction *enterAction = [UIAlertAction
                              actionWithTitle:@"Enter"
                              style:UIAlertActionStyleDefault
                              handler:^(UIAlertAction *action) {
                                  NSLog(@"Enter Action");
                                  NSString *name = ((UITextField *)[alertController.textFields objectAtIndex:0]).text;
                                  NSString *time = ((UITextField *)[alertController.textFields objectAtIndex:1]).text;
                                  [alertController dismissViewControllerAnimated:YES completion:nil];
                                  NSLog(@"%@", name);
                                  NSLog(@"%@", time);
                                  return name;
                              }];

    [alertController addTextFieldWithConfigurationHandler:^(UITextField *textField) {
    textField.placeholder = NSLocalizedString(@"Name", @"Name");
    }];

    [alertController addTextFieldWithConfigurationHandler:^(UITextField *textField) {
    textField.placeholder = NSLocalizedString(@"Time", @"Time");
    }];

    [alertController addAction:cancelAction];
    [alertController addAction:enterAction];
    [self presentViewController:alertController animated:YES completion:nil];
}

Answer 1

This error shows because in UIAlertAction handler you return string. You can set textField text to controller like that:

__weak TableViewController *weakSelf = self;

UIAlertAction *enterAction = [UIAlertAction
                              actionWithTitle:@"Enter"
                              style:UIAlertActionStyleDefault
                              handler:^(UIAlertAction *action) {
                                  NSString *name = ((UITextField *)[alertController.textFields objectAtIndex:0]).text;
                                  NSString *time = ((UITextField *)[alertController.textFields objectAtIndex:1]).text;
                                  [alertController dismissViewControllerAnimated:YES completion:nil];
                                  weakSelf.result = name;
                              }];