WARNING-[UIApplication delegate] 只能在主线程中使用

Question

我收到警告 [UIApplication delegate] must be used from main thread only in the below line of code

((AppDelegate *)[[UIApplication sharedApplication] delegate]).loginProfile.accessToken;

以下是我的代码。

+ (NSString *)accessTokenHashForDate:(NSDate *)date withParameters:(NSArray *)params{

    NSString *accessToken = ((AppDelegate *)[[UIApplication sharedApplication] delegate]).loginProfile.accessToken;

    NSString *paramsStr = [params componentsJoinedByString:@""];
    NSString *hashStr = [NSString stringWithFormat:@"%@%@%@%@", [CommonUtil IMEI], [date agileHashFormattedString], (!paramsStr) ? @"" : paramsStr, accessToken];
    return hashStr
}

谁能告诉我如何删除这个警告信息？

Answer 1

您必须通过放入下面的代码块在主线程中运行此代码，

dispatch_async(dispatch_get_main_queue(), ^{
    // Put your code here
})

你可以像这样使用这个块，

 + (NSString *)accessTokenHashForDate:(NSDate *)date withParameters:(NSArray *)params{
        NSString *hashStr = @"";
        dispatch_async(dispatch_get_main_queue(), ^{
            NSString *accessToken = ((AppDelegate *)[[UIApplication sharedApplication] delegate]).loginProfile.accessToken;
            NSString *paramsStr = [params componentsJoinedByString:@""];
            hashStr = [NSString stringWithFormat:@"%@%@%@%@", [CommonUtil IMEI], [date agileHashFormattedString], (!paramsStr) ? @"" : paramsStr, accessToken];
        });
        return hashStr;
    }

或者在dispatch_async块中调用accessTokenHashForDate function。

dispatch_async(dispatch_get_main_queue(), ^{
    // Call Function here
});

Answer 2

+ (NSString *)accessTokenHashForDate:(NSDate *)date withParameters:(NSArray *)params{
__block NSString *accessToken = NULL;
if ([NSThread isMainThread]) {
        accessToken = ((AppDelegate *)[[UIApplication sharedApplication] delegate]).loginProfile.accessToken;


} else {
    dispatch_semaphore_t semaphore = dispatch_semaphore_create(1);
    dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
    dispatch_async(dispatch_get_main_queue(), ^{
        accessToken = ((AppDelegate *)[[UIApplication sharedApplication] delegate]).loginProfile.accessToken;
        dispatch_semaphore_signal(semaphore);
    });
    dispatch_semaphore_wait(semaphore, DISPATCH_TIME_FOREVER);
    dispatch_semaphore_signal(semaphore);
}
NSString *paramsStr = [params componentsJoinedByString:@""];
           NSString *hashStr = [NSString stringWithFormat:@"%@%@%@%@", [CommonUtil IMEI], [date agileHashFormattedString], (!paramsStr) ? @"" : paramsStr, accessToken];
return hashStr;

}