UIAlertController

- (IBAction)onClickAmount:(id)sender {

    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"" message:@"" preferredStyle:UIAlertControllerStyleAlert];

    [alertController addTextFieldWithConfigurationHandler:^(UITextField * _Nonnull textField) {

        textField.placeholder = @"물량을 입력하세요";

        textField.secureTextEntry = NO;

        textField.keyboardType = UIKeyboardTypeNumberPad;

    }];

    UIAlertAction *confirmAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {

        NSLog(@"물량을 입력하세요 %@", [[alertController textFields][0] text]);

        //compare the current password and do action here

 

    }];

    [alertController addAction:confirmAction];

    UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"Cancel" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {

        NSLog(@"Canelled");

    }];

    [alertController addAction:cancelAction];

    [self presentViewController:alertController animated:YES completion:nil];

}