解决 iOS 11 webview 顶部空白条的问题

在 iOS 11 使用 webview 发现顶部会有一个空白条，怎么也去不掉，通过设置 contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever 就可以解决了，具体的代码如下：

////  ViewController.m//  webView////  Created by exchen on 18/7/14.//  Copyright © 2018年 exchen. All rights reserved.// #import "ViewController.h" @interface ViewController ()  @property(nonatomic, strong) UIWebView* webView;@end @implementation ViewController - (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.        CGRect screen = [[UIScreen mainScreen] bounds];        //添加 UIWebView    self.webView = [[UIWebView alloc] initWithFrame: CGRectMake(0, 0, screen.size.width, screen.size.height)];        [self.view addSubview: self.webView];        NSURL * url = [NSURL URLWithString: @"https://www.exchen.net"];    NSURLRequest * request = [NSURLRequest requestWithURL:url];    [self.webView loadRequest:request];    self.webView.delegate = self;        //解决 iOS 11 屏幕顶部显示不全    if ([[UIDevice currentDevice].systemVersion floatValue] >= 11.0) {                self.webView.scrollView.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;    }    } - (void)didReceiveMemoryWarning {    [super didReceiveMemoryWarning];    // Dispose of any resources that can be recreated.} - (void)webViewDidStartLoad:(UIWebView *)webView {    NSLog(@"%@",NSStringFromSelector(_cmd));} //加载失败时调用- (void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error {    NSLog(@"%@",NSStringFromSelector(_cmd));    NSLog(@"error: %@",error);        UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"信息" message:@"连接服务器失败，请检查网络" preferredStyle:UIAlertControllerStyleAlert];        UIAlertAction *cancelAction = [UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleCancel handler:^(UIAlertAction *action){                exit(0);    }];        [alertController addAction:cancelAction];        [self presentViewController:alertController animated:YES completion:nil];} - (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{        return true;} @end

原文地址：https://www.exchen.net/%E8%A7%A3%E5%86%B3-ios-11-webview-%E9%A1%B6%E9%83%A8%E7%A9%BA%E7%99%BD%E6%9D%A1%E7%9A%84%E9%97%AE%E9%A2%98.html