Question

I used the codes below to execute my program

for(int i=0;i<100000000000000000000;i++)
{
//dosomething
}

I want to make the computer still respond to user interaction when processing to avoid a system block.

Answer 1

You can use Grand Central Dispatch. It’s like BackgroundWorker/Task in .NET. Ray Wenderlich also has a great tutorial.

Eg:

dispatch_queue_t q = dispatch_get_global_queue(0, 0);
dispatch_queue_t main = dispatch_get_main_queue();
dispatch_async(q, ^{
    // long running database operation
    dispatch_async(main, ^{

   });
});