文本字段位于时不调用 UIAlertView clickedButtonAtIndex

Question

当我有以下代码时，将调用 clickedButtonAtIndex 委托方法：

UIAlertView * alertTextField = [[UIAlertView alloc] initWithTitle:@"Post To Facebook" message:@"What would you like the post to say?" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Continue", nil];
        alertTextField.tag = 2;
        [alertTextField show];

但是当我在 UIAlertViewStylePlainTextInput 中添加时，委托方法没有被调用。

 UIAlertView * alertTextField = [[UIAlertView alloc] initWithTitle:@"Post To Facebook" message:@"What would you like the post to say?" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Continue", nil];
        [alertTextField setAlertViewStyle:UIAlertViewStylePlainTextInput];
        alertTextField.tag = 2;
        [alertTextField show];

这是为什么？

Answer 1

确保您在视图控制器中添加了 <UIAlertViewDelegate> 而您忘记添加 alertTextField.delegate = self; 然后实现委托以接收事件。

UIAlertView * alertTextField = [[UIAlertView alloc] initWithTitle:@"Post To Facebook" message:@"What would you like the post to say?" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Continue", nil];
[alertTextField setAlertViewStyle:UIAlertViewStylePlainTextInput];
alertTextField.delegate = self; // you forget to add this line 
alertTextField.tag = 2;
[alertTextField show];


-(void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
    if (buttonIndex == 0) {
      NSString *test = [[alertView textFieldAtIndex:0] text];
    }
 }

UIAlertView no longer available/support in iOS 8 and above so in this place use UIAlertViewController, example for how to use UIAlertViewController see this tutorial

文本字段位于时不调用 UIAlertView clickedButtonAtIndex

UIAlertView clickedButtonAtIndex not called when text field is in

delegates

uialertview

ios