如何让 NSOperationQueue(或其他任何东西)等待两个带有回调的异步网络调用?流程需要看起来像这样
Block Begins {
Network call with call back/block begins {
first network call is done
}
}
Second Block Begins {
Network call with call back/block begins {
second network call is done
}
}
Only run this block once the NETWORK CALLS are done {
blah
}
这是我目前所拥有的。
NSOperationQueue *queue = [[NSOperationQueue alloc] init];
__block NSString *var;
[queue addOperation:[NSBlockOperation blockOperationWithBlock:^{
[AsyncReq get:^{
code
} onError:^(NSError *error) {
code
}];
}]];
[queue addOperation:[NSBlockOperation blockOperationWithBlock:^{
[AsyncReq get:^{
code
} onError:^(NSError *error) {
code
}];
}]];
[queue waitUntilAllOperationsAreFinished];
//do something with both of the responses
最佳答案
你必须使用NSOperation Queue
吗?以下是使用调度组执行此操作的方法:
dispatch_group_t group = dispatch_group_create();
dispatch_group_enter(group);
[AsyncReq get:^{
code
dispatch_group_leave(group);
} onError:^(NSError *error) {
code
dispatch_group_leave(group);
}];
dispatch_group_enter(group);
[AsyncReq get:^{
code
dispatch_group_leave(group);
} onError:^(NSError *error) {
code
dispatch_group_leave(group);
}];
dispatch_group_notify(group, dispatch_get_main_queue(), ^{
NSLog(@"Both operations completed!")
});
关于ios - NSOperationQueue 如何等待两个异步操作?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/27259570/