When is UIViewController viewDidUnload called?

Question

Note: This question is outdated—viewDidUnload is deprecated iOS 6.

When does UIViewController\'s viewDidUnload automatically get called? Yes I

Answer 1

In addition to manually issuing a memory warning in the simulator, you can issue one programatically with

- (void)_simulateLowMemoryWarning {
  // Send out MemoryWarningNotification
  [[NSNotificationCenter defaultCenter] postNotificationName:UIApplicationDidReceiveMemoryWarningNotification
                                                      object:[UIApplication sharedApplication]];
  // Manually call applicationDidReceiveMemoryWarning
  [[[UIApplication sharedApplication] delegate] applicationDidReceiveMemoryWarning:[UIApplication sharedApplication]];
}

You can then cause this to happen every 5 seconds using a timer

static NSTimer *gLowMemoryTimer = nil;

- (void)stopLowMemoryTimer {
  [gLowMemoryTimer invalidate];
  gLowMemoryTimer = nil;
}

- (void)startLowMemoryTimer {
  if (gLowMemoryTimer) {
    [self _stopLowMemoryTimer];
  }
  gLowMemoryTimer = [NSTimer scheduledTimerWithTimeInterval:5.0 target:self selector:@selector(_simulateLowMemoryWarning) userInfo:nil repeats:YES];
}