self.automaticallyAdjustsScrollViewInsets = NO;
self.edgesForExtendedLayout = UIRectEdgeNone;
_webView = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0,UIScreenWidth, UIScreenHeight–64)];
self.automaticallyAdjustsScrollViewInsets = NO;
self.edgesForExtendedLayout = UIRectEdgeNone;
_webView = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0,UIScreenWidth, UIScreenHeight–64)];