Prevent conflict GestureEvent

In Google map, scroll event is already set up.
I would like to use UIPanGestureRecognizer in UIWebView but, cannot first.
To prevent this, we need one technique

Prepare GestureRecognizerDelegate

@interface TestController : UIViewController<UIGestureRecognizer>
@end

Implement gestureRecognizer methods

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
     if ([otherGestureRecognizer isKindOfClass:[UIGestureRecognizer class]]) {
         return YES;
     }
     return NO;
}
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneousWithGestureRecognizer(UIGestureRecognizer *)otherGestureRecognizer {
     return YES;
}