ios - 如何知道推送通知权限警报是否已经显示

Question

我想实现一个自定义屏幕，通知我的用户我为什么要请求推送通知权限。在他们按下自定义屏幕中的按钮后，我使用 [[UIApplication sharedApplication] registerForRemoteNotificationTypes:

显示 iOS 推送通知权限对话框

如果用户还没有看到推送通知权限对话框，我只想显示此自定义屏幕一次。我不能使用 [[UIApplication sharedApplication] enabledRemoteNotificationTypes] == UIRemoteNotificationTypeNone，因为如果用户决定不允许推送通知，这也会返回“无”。

有什么想法吗？

Answer 1

你可以使用 NSUserDefaults :

#define kPushNotificationRequestAlreadySeen @"PushNotificationRequestAlreadySeen"

if(![[NSUserDefaults standardUserDefaults] boolForKey:kPushNotificationRequestAlreadySeen]) {

    // Notify the user why you want to have push notifications
    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:... delegate:self ...];
    [alertView show];

    [[NSUserDefaults standardUserDefaults] setBool:YES forKey:kPushNotificationRequestAlreadySeen];
}
else {
    // Already allowed -> register without notifying the user
    [[UIApplication sharedApplication] registerForRemoteNotificationTypes:UIRemoteNotificationTypeAlert | UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeSound];
}

和

- (void)alertView:(UIAlertView*)alertView didDismissWithButtonIndex:(NSInteger)index {
    // Actually registering to push notifications
    [[UIApplication sharedApplication] registerForRemoteNotificationTypes:UIRemoteNotificationTypeAlert | UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeSound];
}