iphone - 在UIAlertView上出现一些错误

Question

我不知道为什么会这样。在我看来，这是正确的。我写了另一个UIAlertView，看起来还不错，一删除它，它就会错误处理我写的那个。我正在尝试遵循tutorial。

这是在我的viewcontroller.m中

- (void)messageComposeViewController:(MFMessageComposeViewController *)controller didFinishWithResult:(MessageComposeResult)result
{


switch (result) {
        case MessageComposeResultCancelled:
            NSLog(@"Cancelled");
            break;
        case MessageComposeResultFailed:
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Welcome To My App" message:@"This app will ... First you need to ..." delegate:self cancelButtonTitle:@"Ok" otherButtonTitles:nil];
            [alert show];
            [alert release];

        break;
    case MessageComposeResultSent:

        break;
    default:
        break;
}

[self dismissModalViewControllerAnimated:YES];
}

错误显示在错误的许多行上，例如:消息发送表达式开头缺少“[”。 (如果我把它放进去，它要在initWithTitle之后再放一个:)

下一个错误是:使用未声明的标识符“警报”(在演出和发行中这样说)

知道发生了什么吗？提前致谢。

Answer 1

尝试在包含多行的case语句中添加方括号。

- (void)messageComposeViewController:(MFMessageComposeViewController
*)controller didFinishWithResult:(MessageComposeResult)result {


switch (result) {
        case MessageComposeResultCancelled:
            NSLog(@"Cancelled");
            break;
        case MessageComposeResultFailed: {
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Welcome To My App" message:@"This app will ... First you need to ..." delegate:self cancelButtonTitle:@"Ok" otherButtonTitles:nil];
            [alert show];
            [alert release];

        break;
        }
    case MessageComposeResultSent:

        break;
    default:
        break; }

[self dismissModalViewControllerAnimated:YES]; }