How to wrap an asynchronous method that takes a block and turn it synchronous in Objective-C

Question

I want to wrap an async API that look like this:

[someObject completeTaskWithCompletionHandler:^(NSString *result) {

}];

into a synchronous m

Answer 1

Using an NSRunLoop is the easiest to do here.

__block NSString* result = nil;
[self completeTaskWithCompletionHandler:^(NSString *resultstring) {
    result = resultstring;
}];
while (!result) {
    [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantFuture]];
}