WKWebView支持ios8之后，优点：
1.更多的支持HTML5的特性
2.官方宣称的高达60fps的滚动刷新率以及内置手势
3.Safari相同的JavaScript引擎
4.占用更少的内存
一、基本使用
WKWebView有两个delegate,WKUIDelegate和WKNavigationDelegate。WKNavigationDelegate主要处理一些跳转、加载处理操作，WKUIDelegate主要处理JS脚本，确认框，警告框等。因此WKNavigationDelegate更加常用。
1.导入头文件#import<WebKit/WebKit.h>
2.相对应的使用方法：
备注：WKWebViewConfiguration和WKPreferences中有很多属性可以对webview初始化进行设置
WKWebViewConfiguration *config = [[WKWebViewConfiguration alloc] init];
config.selectionGranularity = WKSelectionGranularityDynamic;
config.allowsInlineMediaPlayback = YES;
WKPreferences *preferences = [WKPreferences new];
//是否支持JavaScript
preferences.javaScriptEnabled = YES;
//不通过用户交互，是否可以打开窗口
preferences.javaScriptCanOpenWindowsAutomatically = YES;
config.preferences = preferences;
WKWebView *webview = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0, KScreenWidth, KScreenHeight - 64) configuration:config];
[self.view addSubview:webview];
/* 加载服务器url的方法*/
NSString *url = @"https://www.baidu.com";
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:url]];
[webview loadRequest:request];
webview.navigationDelegate = self;
webview.UIDelegate = self;
遵循的协议和实现的协议方法：
#pragma mark - WKNavigationDelegate
/* 页面开始加载 */
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation{
}
/* 开始返回内容 */
- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation{
}
/* 页面加载完成 */
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{
}
/* 页面加载失败 */
- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(WKNavigation *)navigation{
}
/* 在发送请求之前，决定是否跳转 */
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler{
//允许跳转
decisionHandler(WKNavigationActionPolicyAllow);
//不允许跳转
//decisionHandler(WKNavigationActionPolicyCancel);
}
/* 在收到响应后，决定是否跳转 */
- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler{
NSLog(@"%@",navigationResponse.response.URL.absoluteString);
//允许跳转
decisionHandler(WKNavigationResponsePolicyAllow);
//不允许跳转
//decisionHandler(WKNavigationResponsePolicyCancel);
}
#pragma mark - WKUIDelegate
// 创建一个新的WebView
- (WKWebView*)webView:(WKWebView*)webView createWebViewWithConfiguration:(WKWebViewConfiguration*)configuration forNavigationAction:(WKNavigationAction*)navigationAction windowFeatures:(WKWindowFeatures*)windowFeatures{
return[[WKWebViewalloc]init];
}
// 输入框
- (void)webView:(WKWebView*)webView runJavaScriptTextInputPanelWithPrompt:(NSString*)prompt defaultText:(nullableNSString*)defaultText initiatedByFrame:(WKFrameInfo*)frame completionHandler:(void(^)(NSString* __nullableresult))completionHandler{
completionHandler(@"http");
}// 确认框
- (void)webView:(WKWebView*)webView runJavaScriptConfirmPanelWithMessage:(NSString*)message initiatedByFrame:(WKFrameInfo*)frame completionHandler:(void(^)(BOOLresult))completionHandler{
completionHandler(YES);
}
// 警告框
- (void)webView:(WKWebView*)webView runJavaScriptAlertPanelWithMessage:(NSString*)message initiatedByFrame:(WKFrameInfo*)frame completionHandler:(void(^)(void))completionHandler{
NSLog(@"%@",message); completionHandler();
}
url中文处理
有时候我们加载的URL中可能会出现中文，需要我们手动进行转码，但是同时又要保证URL中的特殊字符保持不变，那么我们就可以使用下面的方法（方法放到了NSString中的分类中）：
- (NSURL *)url{
#pragma clang diagnostic push
#pragma clang diagnostic ignored"-Wdeprecated-declarations"
return [NSURL URLWithString:(NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, (CFStringRef)self, (CFStringRef)@"!$&'()*+,-./:;=?@_~%#[]", NULL,kCFStringEncodingUTF8))];
#pragma clang diagnostic pop
}
获取h5中的标题 和进度条
在初始化wenview时，添加两个观察者分别用来监听webview 的estimatedProgress和title属性：
webview.navigationDelegate = self;
webview.UIDelegate = self;
[webview addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew context:nil];
[webview addObserver:self forKeyPath:@"title" options:NSKeyValueObservingOptionNew context:NULL];
实现观察者的回调方法：
-(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context{
if ([keyPath isEqualToString:@"estimatedProgress"]) {
//进度条设置
if ([change[@"new"] floatValue] <[change[@"old"] floatValue]) {
return;
}
//进度条设置 if ([change[@"new"]floatValue] == 1.0) {
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
//进度条设置
});
}
}else if ([keyPath isEqualToString:@"title"]){
//标题设置
}
}
添加userAgent信息
在Appdelegate中添加一个WKWebview的属性，启动app时直接，为该属性添加userAgent：
- (void)setUserAgent {
_webView = [[WKWebView alloc] initWithFrame:CGRectZero];
[_webView evaluateJavaScript:@"navigator.userAgent" completionHandler:^(id result, NSError *error) {
if (error) { return; }
NSString *userAgent = result;
if (![userAgent containsString:@"/mobile-iOS"]) {
userAgent = [userAgent stringByAppendingString:@"/mobile-iOS"];
NSDictionary *dict = @{@"UserAgent": userAgent};
[TKUserDefaults registerDefaults:dict];
}
}];
}
原生JS交互
（一）JS调用原生方法
在WKWebView中实现与JS的交互还需要实现另外一个代理方法：WKScriptMessageHandler
#pragma mark - WKScriptMessageHandler
- (void)userContentController:(WKUserContentController *)userContentController
didReceiveScriptMessage:(WKScriptMessage *)message
备注：JS只能向原生传递一个参数，所以如果有多个参数需要传递，可以让JS传递对象或者JSON字符串即可。
（二）原生调用JS方法
[webview evaluateJavaScript:“JS语句” completionHandler:^(id _Nullable data, NSError * _Nullable error) {
}];
