How to set two buttons to turn on/off vibration on iOS ?

Question

How to set two buttons to turn on/off vibration on iOS ?

This is what I was trying to do:

@property (nonatomic) BOOL vibeIsOn;

- (IBAction)startVibrating:(id)sender {
dispatch_queue_t vibeQueue = dispatch_queue_create("vibe", NULL);
dispatch_sync(vibeQueue, ^{

    for (;!self.vibeIsOn;)
    {
        AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);

    }
});
dispatch_release(vibeQueue);}

- (IBAction)stopVibrating:(id)sender {
self.vibeIsOn = YES;
AudioServicesRemoveSystemSoundCompletion(kSystemSoundID_Vibrate);}

Unfortunately, when I press the "staring vibrating" button, it just can not jump out of the for loop, but I did put the for loop in a thread, right?

Help!!! Is anything wrong with this code?

Answer 1

You dispatch the queue synchronously, so the calling thread waits until the execution finishes (which never happens because you for loop never stops). Use dispatch_async instead.