ios如何从appdelegate发送refreshToken到视图控制器

Question

我是开发IOS应用程序的初学者。现在我想从AppDelegate中的方法向mainViewController发送一个refreshToken数据。 下载它时，我无法第一时间得到它。但第二次，我可以得到它。 我认为它需要一些时间，它创建第一次，它被存储后。 请帮助我，如何将数据从AppDelegate发送到ViewController。最终，我想将它存储到数据库并从服务器端向用户发送推送通知消息。 我使用下面的代码。

//AppDelegate.h

@class ViewController; 
#import <UIKit/UIKit.h> 
#import "ViewController.h" 
@interface AppDelegate : UIResponder <UIApplicationDelegate> 
@property (weak, nonatomic) ViewController *myViewController; 
@property (strong, nonatomic) UIWindow *window; 
@property (weak, nonatomic) IBOutlet UIWebView *webView;  
@end 

//AppDelegate.m

- (void)tokenRefreshCallback: (NSNotification *)notification { 
NSString *refreshToken = [[FIRInstanceID instanceID] token]; 
NSLog(@"InstanceID token: %@", refreshToken); 

// 
if(refreshToken){ 
    [[NSUserDefaults standardUserDefaults] setObject:refreshToken forKey:@"token"]; 
    [[NSUserDefaults standardUserDefaults] synchronize]; 
} 
// Connect to FCM since connection may have failed when attempted before having a token. 

[self connectToFirebase]; 

} 

//ViewController.h

#import <UIKit/UIKit.h> 
#import "AppDelegate.h" 
@interface ViewController : UIViewController 

@end 

//ViewController.m

- (void)viewDidLoad { 
[super viewDidLoad]; 

AppDelegate *appDelegate = [[UIApplication sharedApplication] delegate]; 
appDelegate.myViewController = self; 

//get tokenId 
NSString *token = [[NSUserDefaults standardUserDefaults] objectForKey:@"token"]; 
if(token){ 
    NSLog(@"i have token~!!!: %@ ", token); 
}else NSLog(@"no token!: %@ ", token); 
// Do any additional setup after loading the view, typically from a nib.  

} 

谢谢大家。

Answer 1

使用NSNotifiactionCenter

在当令牌可用后使用令牌通知您的appdelegate

NSDictionary* userInfo = @{@"token": @"YOUR_TOKEN"}; 

[[NSNotificationCenter defaultCenter] postNotificationName:@"refreshTokenAvailale" object:self userInfo:userInfo]; 

（在应用程序委托其中token可以添加以下代码），并把这个代码在你的主视图控制器

- (void) dealloc 
{ 
// If you don't remove yourself as an observer, the Notification Center 
// will continue to try and send notification objects to the deallocated 
// object. 
    [[NSNotificationCenter defaultCenter] removeObserver:self]; 

} 

- (id) init 
{ 

    [[NSNotificationCenter defaultCenter] addObserver:self 
    selector:@selector(receiveNotification:) 
    name:@"refreshTokenAvailale" 
    object:nil]; 

    return self; 
} 

- (void) receiveNotification:(NSNotification *) notification 
{ 

    if ([notification.name isEqualToString:@"refreshTokenAvailale"]) 
    { 
     NSDictionary* userInfo = notification.userInfo; 
     NSString* token = userInfo[@"token"]; 
    } 

}