AlertView with password

1. setAlertViewStyle:UIAlertViewStyleSecureTextInput

UIAlertView *alertView = [[UIAlertView alloc]
    initWithTitle:@"Password"
    message:@"Please enter your password:"
    delegate:self
    cancelButtonTitle:@"Cancel"
    otherButtonTitles:@"Ok", nil];

[alertView setAlertViewStyle:UIAlertViewStyleSecureTextInput];
[alertView show];

2. setAlertViewStyle:UIAlertViewStyleLoginAndPasswordInput

...
[alertView setAlertViewStyle:UIAlertViewStyleLoginAndPasswordInput];
...