How to wait for a thread to finish in Objective-C

Question

I\'m trying to use a method from a class I downloaded somewhere. The method executes in the background while program execution continues. I do not want to allow program exec

Answer 1

For such cases I usually using NSCondition class.

//this method executes in main thread/queue
- (void)waitForJob
{
    id __weak selfWeak = self;
    NSCondition *waitHandle = [NSCondition new];
    [waitHandle lock];
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), ^{
        [selfWeak doSomethingLongtime];
        [waitHandle signal];
    });
    //waiting for background thread finished
    [waitHandle waitUntilDate:[NSDate dateWithTimeIntervalSinceNow:60]];
}