iOS WKWebView基本使用

9 个月前

Kevin Chiang

WKWebView加载网络文件

在ViewController里面新建一个wkwebview属性，我们初始化它并且加入到视图中来，加载 https://www.baidu.com 这个URL。

- (void)viewDidLoad {
    [super viewDidLoad];
    self.title = @"WKWebview";
    self.webview = [[WKWebView alloc] initWithFrame:self.view.bounds];
    [self.view addSubview:self.webview];
    self.webview.navigationDelegate = self;
    NSURL *url = [NSURL URLWithString:@"https://www.baidu.com"];
    NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];
    [self.webview loadRequest:request];

WKWebView加载本地文件

如果是加载本地html文件，可以使用loadFileURL这个方法，写一个本地的html文件，命名比如custom.html，放到主工程中，使用以下代码加载这个custom.html文件。

- (void)viewDidLoad {
    [super viewDidLoad];
    self.title = @"WKWebview";
    self.webview = [[WKWebView alloc] initWithFrame:self.view.bounds];
    [self.view addSubview:self.webview];
    self.webview.navigationDelegate = self;
    NSString *htmlPath = [[NSBundle mainBundle] pathForResource:@"custom" ofType:@"html"];
    NSURL *fileUrl = [NSURL fileURLWithPath:htmlPath];
    [self.webview loadFileURL:fileUrl allowingReadAccessToURL:fileUrl];

WKWebView代理方法

可以看到我们设置了navigationDelegate为self，所以ViewController需要实现对应的协议方法。navigationDelegate是WKWebView提供的代理方法，包含了WKWebView在加载期间的各种回调。

//在网络加载前调用，用于前置拦截一些网络请求，WKNavigationActionPolicyAllow代表允许请求，WKNavigationActionPolicyCancel代表取消请求
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler
    NSLog(@"decidePolicyForNavigationAction");
    decisionHandler(WKNavigationActionPolicyAllow);
//网络请求开始的代理方法
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation
    NSLog(@"didStartProvisionalNavigation");
//在网络加载后调用，在收到网络响应后拦截，WKNavigationActionPolicyAllow代表允许网页加载，WKNavigationActionPolicyCancel代表取消网页加载
- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler
    NSLog(@"decidePolicyForNavigationResponse");
    decisionHandler(WKNavigationResponsePolicyAllow);
//网络请求开始的代理方法
- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation
    NSLog(@"didCommitNavigation");
//网络请求结束的代理方法，网络请求成功或者失败都会调用，需要在navigation里面获取response响应判断statusCode
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation
    NSLog(@"didFinishNavigation");
//网络请求结束的代理方法，这种情况对应的是网络传输的错误
- (void)webView:(WKWebView *)webView didFailNavigation:(WKNavigation *)navigation withError:(NSError *)error
    NSLog(@"didFailNavigation");
//网络请求结束的代理方法，这种情况对应的是请求没有到达服务端，比如请求的url不存在，在DNS解析的时候找不到IP地址
- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(WKNavigation *)navigation withError:(NSError *)error
    NSLog(@"didFailProvisionalNavigation");
//收到301或者302重定向请求的时候调用
- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(WKNavigation *)navigation
    NSLog(@"didReceiveServerRedirectForProvisionalNavigation");
//WKWebView进程被终止的时候调用
- (void)webViewWebContentProcessDidTerminate:(WKWebView *)webView
    NSLog(@"webViewWebContentProcessDidTerminate");