// called when the recognition of one of gestureRecognizer or otherGestureRecognizer would be blocked by the other
// return YES to allow both to recognize simultaneously. the default implementation returns NO (by default no two gestures can be recognized simultaneously)
意思是说，返回yes的话，允许二者同时处理手势交互，（假如是webview的话，可以用添加个单击手势，但不会影响，webview的滚动手势），返回NO,不接受外部手势
//
// note: returning YES is guaranteed to allow simultaneous recognition. returning NO is not guaranteed to prevent simultaneous recognition, as the other gesture‘s delegate may return YES
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer;
//**例子
NSURL *url = [NSURL URLWithString:urlArray[idx]];
NSURLRequest *request = [NSURLRequest requestWithURL:url];
[webView loadRequest:request];
webView.userInteractionEnabled = YES;
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleWebView:)];
singleTap.delegate= self;
singleTap.cancelsTouchesInView =NO;
[webView addGestureRecognizer:singleTap];
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
return Yes; //返回yes,webView上的手势起作用。
return No ;返回No,或不调用这个方法webview上的手势不起作用。
}
原文：http://www.cnblogs.com/TheYouth/p/5758335.html