如何在ViewController中共享用户设备令牌

Question

我试图找到一种方法让用户可以找到他们的设备令牌（出于调试原因）。

---

我试过这个：

AppDelegate.h

...
@interface MyAppDelegate : UIResponder <UIApplicationDelegate> {
    NSString *token;
}
@property (nonatomic, retain) NSString *token;
...

AppDelegate.m

...

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {
    _token = [[deviceToken description] stringByTrimmingCharactersInSet: [NSCharacterSet characterSetWithCharactersInString:@"<>"]];
    _token = [_token stringByReplacingOccurrencesOfString:@" " withString:@""];
    NSUInteger lenthtotes = [_token length];
    NSUInteger req = 64;

    if (lenthtotes == req){
        NSLog(@"uploaded token: %@", _token);
        upload_token = _token;
    } else {
        _token = @"";
    }
    ...

ViewController.m

NSString *token;
- (void)viewDidLoad
{
    [super viewDidLoad];
    MyAppDelegate *appDelegate = (MyAppDelegate*)[[UIApplication sharedApplication] delegate];
    token = appDelegate.token;
    NSLog(token);
...

AppDelegate中的日志正常工作并返回设备令牌。 但是ViewController里面的日志什么都没有回来？

Answer 1

您无法以这种方式检索令牌是正常的，因为在您的视图控制器的viewDidLoad方法中，您还没有获得令牌。 您应该推送，而不是从AppDelegate 检索。我会使用一个通知：

AppDelegate.m

- (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {
    NSString *token = [[deviceToken description] stringByTrimmingCharactersInSet: [NSCharacterSet characterSetWithCharactersInString:@"<>"]];
    token = [_token stringByReplacingOccurrencesOfString:@" " withString:@""];
    NSUInteger lenthtotes = [_token length];
    NSUInteger req = 64;
    if (lenthtotes == req) {
        NSLog(@"uploaded token: %@", token);
        NSNotification *notif = [NSNotification notificationWithName:@"NEW_TOKEN_AVAILABLE" object:token];
        [[NSNotificationCenter defaultCenter] postNotification:notif];
    }
    ...
}

ViewController.m

- (void)viewDidLoad {
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(tokenAvailableNotification:)
                                                 name:@"NEW_TOKEN_AVAILABLE"
                                               object:nil];
}

- (void)tokenAvailableNotification:(NSNotification *)notification {
    NSString *token = (NSString *)notification.object;
    NSLog(@"new token available : %@", token);
}

- (void)dealloc {
    [NSNotificationCenter defaultCenter] removeObserver:self];
}

Answer 2

最简单的方法是从通知委托方法中获取它：

@interface MyAppDelegate : UIResponder <UIApplicationDelegate>
{
    // No need to define backing variables
}

@property (nonatomic, retain) NSString *token;

- (void)application:(UIApplication *)app didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken 
{
    NSString *token = [[deviceToken description] stringByTrimmingCharactersInSet: [NSCharacterSet characterSetWithCharactersInString:@"<>"]];
    self.token = [token stringByReplacingOccurrencesOfString:@" " withString:@""];
} 

请注意，您必须使用与启用APNS的应用ID相关联的配置文件进行编译。如果未正确配置APNS，则可能无法收到令牌。

作为旁注，在使用属性时无需定义实例变量。编译器将处理设置后备变量，并管理所有这些变量;你只需定义@property并通过预定义的setter和getters（self.variableName）访问它。