自iOS8之后苹果推出了WKWebView,WKWebView相比于UIWebView性能更好，对于不需要支持iOS8的app,可以考虑将UIWebView切换到WKWebView.下面从四个方面介绍WKWebView的使用。
1.加载网页，加载网页比较简单，以加载本地网页为例：
WKWebView *webView = [[WKWebView alloc] initWithFrame:self.view.bounds configuration:configuration];
webView.navigationDelegate = self;
webView.UIDelegate = self;
//加载本地网页
NSString *path = [[NSBundle mainBundle] pathForResource:@"JSCallOC.html" ofType:nil];
NSURL *url = [[NSURL alloc] initFileURLWithPath:path];
[webView loadFileURL:url allowingReadAccessToURL:url];
2.webView加载的相关回调
#pragma WKNavigatonDelegate
// 1 页面开始加载
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation {
}
// 2 开始获取到网页内容时返回
- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation {
}
//3 页面加载完成之后调用
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation {
}
//4 页面加载失败之后调用
- (void)webView:(WKWebView *)webView didFailNavigation:(WKNavigation *)navigation withError:(NSError *)error {
}
// 5接收到服务器跳转请求之后调用
- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(WKNavigation *)navigation{
}
// 6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);
}
// 7在发送请求之前，决定是否跳转
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler{
// NSLog(@"%@",navigationAction.request.URL.absoluteString);
// //允许跳转
decisionHandler(WKNavigationActionPolicyAllow);
//不允许跳转
//decisionHandler(WKNavigationActionPolicyCancel);
}
#pragma WKUIDelegate
// 创建一个新的WebView
- (WKWebView *)webView:(WKWebView *)webView createWebViewWithConfiguration:(WKWebViewConfiguration *)configuration forNavigationAction:(WKNavigationAction *)navigationAction windowFeatures:(WKWindowFeatures *)windowFeatures{
return [[WKWebView alloc]init];
}
// 输入框
- (void)webView:(WKWebView *)webView runJavaScriptTextInputPanelWithPrompt:(NSString *)prompt defaultText:(nullable NSString *)defaultText initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(NSString * __nullable result))completionHandler{
completionHandler(@"http");
}
// 确认框
- (void)webView:(WKWebView *)webView runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(BOOL result))completionHandler{
completionHandler(YES);
}
// 警告框
- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler{
NSLog(@"%@",message);
completionHandler();
}
3.WKWebView的进度条显示
WKWebView自带一个属性estimatedProgress，我们可以通过监听它的改变来制作进度条，相比于UIWebView不带进度条要方便很多.
@interface ViewController ()
@property (nonatomic, weak) WKWebView *webView;
@property (nonatomic, weak) UIProgressView *progressBar;
@end
- (void)viewDidLoad {
[super viewDidLoad];
[self configWebView];
[self configProgressBar];
}
- (void)configWebView {
//配置环境
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc]init];
WKWebView *webView = [[WKWebView alloc] initWithFrame:self.view.bounds configuration:configuration];
webView.navigationDelegate = self;
webView.UIDelegate = self;
//加载本地网页
NSString *path = [[NSBundle mainBundle] pathForResource:@"JSCallOC.html" ofType:nil];
NSURL *url = [[NSURL alloc] initFileURLWithPath:path];
[webView loadFileURL:url allowingReadAccessToURL:url];
//webView的进度条
[webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew context:nil];
[self.view addSubview:webView];
self.webView = webView;
}
- (void)configProgressBar {
UIProgressView *progressgBar = [[UIProgressView alloc] init];
progressgBar.frame = CGRectMake(0, 0, self.view.frame.size.width, 3);
progressgBar.progress = 0.0;
progressgBar.tintColor = [UIColor blueColor];
[self.view addSubview:progressgBar];
self.progressBar = progressgBar;
}
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
if ([keyPath isEqual: @"estimatedProgress"]) {
self.progressBar.alpha = 1.0;
[self.progressBar setProgress:self.webView.estimatedProgress animated:true];
//进度条的值最大为1.0
if (self.webView.estimatedProgress >= 1) {
[UIView animateWithDuration:0.3 delay:0.1 options:UIViewAnimationOptionCurveEaseInOut animations:^{
self.progressBar.alpha = 0.0;
} completion:^(BOOL finished) {
self.progressBar.progress = 0;
}];
}
}
}
- (void)dealloc{
//这里需要注意，前面增加过的方法一定要remove掉。
[self.webView removeObserver:self forKeyPath:@"estimatedProgress"];
}
4.WKWebView与js交互
WKWebView与js的交互相比于UIWebView要简单一点，OC调用js方法只需要在- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation；的回调方法里面做就好了，比如我们的h5页面有个全局的js方法叫ocCallJs()，该方法返回一个字符串。因为js代码调用是异步的，所以使用block做为回调就可以拿到js方法返回的数据，这一点UIWebView是做不到的。只需要这么调用
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation {
[webView evaluateJavaScript:@"window.ocCallJs()" completionHandler:^(id _Nullable resualt, NSError * _Nullable error) {
NSLog(resualt);
}];
}
js调用OC在WKWebView中也是比较简单的，WKWebView提供了一个叫WKUserContentController类，我们只需要在创建WKWebView的时候，注册js需要回调的OC方法，然后初始化webView,遵循WKScriptMessageHandler，实现- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message ；方法即可，当js调用OC的方法时就会调用这个方法。比如我们的h5页面有个按钮，按钮点击回调OC的方法。
h5页面的js方法需要这样写
function call()
{
//前端需要用 window.webkit.messageHandlers.注册的方法名.postMessage({body:传输的数据} 来给native发送消息,jsCallOC就是我们开始注册的native函数，body里面传递我们想要的参数，如果是需要传递复杂数据，可以利用字典或者son格式传递。
window.webkit.messageHandlers.jsCallOC.postMessage({body: 'hello world!'});
alert("测试")
}
控制器里的完整代码这样写：
#import "ViewController.h"
#import
@interface ViewController ()
@property (nonatomic, weak) WKWebView *webView;
@property (nonatomic, weak) UIProgressView *progressBar;
@property (nonatomic, strong)WKUserContentController *userContentController;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[self configWebView];
[self configProgressBar];
}
- (void)configWebView {
//配置环境
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc]init];
self.userContentController =[[WKUserContentController alloc] init];
//注册方法
[self.userContentController addScriptMessageHandler:self name:@"jsCallOC"];//注册一个name为jsCallOC的js方法
configuration.userContentController = self.userContentController;
WKWebView *webView = [[WKWebView alloc] initWithFrame:self.view.bounds configuration:configuration];
webView.navigationDelegate = self;
webView.UIDelegate = self;
//加载本地网页
NSString *path = [[NSBundle mainBundle] pathForResource:@"JSCallOC.html" ofType:nil];
NSURL *url = [[NSURL alloc] initFileURLWithPath:path];
[webView loadFileURL:url allowingReadAccessToURL:url];
//webView的进度条
[webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew context:nil];
[self.view addSubview:webView];
self.webView = webView;
}
- (void)configProgressBar {
UIProgressView *progressgBar = [[UIProgressView alloc] init];
progressgBar.frame = CGRectMake(0, 0, self.view.frame.size.width, 3);
progressgBar.progress = 0.0;
progressgBar.tintColor = [UIColor blueColor];
[self.view addSubview:progressgBar];
self.progressBar = progressgBar;
}
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
if ([keyPath isEqual: @"estimatedProgress"]) {
self.progressBar.alpha = 1.0;
[self.progressBar setProgress:self.webView.estimatedProgress animated:true];
//进度条的值最大为1.0
if (self.webView.estimatedProgress >= 1) {
[UIView animateWithDuration:0.3 delay:0.1 options:UIViewAnimationOptionCurveEaseInOut animations:^{
self.progressBar.alpha = 0.0;
} completion:^(BOOL finished) {
self.progressBar.progress = 0;
}];
}
}
}
- (void)dealloc{
//这里需要注意，前面增加过的方法一定要remove掉。
[self.userContentController removeScriptMessageHandlerForName:@"jsCallOC"];
[self.webView removeObserver:self forKeyPath:@"estimatedProgress"];
}
#pragma WKNavigatonDelegate
// 1 页面开始加载
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation {
}
// 2 开始获取到网页内容时返回
- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation {
}
//3 页面加载完成之后调用
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation {
[webView evaluateJavaScript:@"window.ocCallJs()" completionHandler:^(id _Nullable resualt, NSError * _Nullable error) {
NSLog(resualt);
}];
}
//4 页面加载失败之后调用
- (void)webView:(WKWebView *)webView didFailNavigation:(WKNavigation *)navigation withError:(NSError *)error {
}
// 5接收到服务器跳转请求之后调用
- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(WKNavigation *)navigation{
}
// 6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);
}
// 7在发送请求之前，决定是否跳转
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler{
// NSLog(@"%@",navigationAction.request.URL.absoluteString);
// //允许跳转
decisionHandler(WKNavigationActionPolicyAllow);
//不允许跳转
//decisionHandler(WKNavigationActionPolicyCancel);
}
#pragma WKUIDelegate
// 创建一个新的WebView
- (WKWebView *)webView:(WKWebView *)webView createWebViewWithConfiguration:(WKWebViewConfiguration *)configuration forNavigationAction:(WKNavigationAction *)navigationAction windowFeatures:(WKWindowFeatures *)windowFeatures{
return [[WKWebView alloc]init];
}
// 输入框
- (void)webView:(WKWebView *)webView runJavaScriptTextInputPanelWithPrompt:(NSString *)prompt defaultText:(nullable NSString *)defaultText initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(NSString * __nullable result))completionHandler{
completionHandler(@"http");
}
// 确认框
- (void)webView:(WKWebView *)webView runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(BOOL result))completionHandler{
completionHandler(YES);
}
// 警告框
- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler{
NSLog(@"%@",message);
completionHandler();
}
#pragma WKWKScriptMessageHandler
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message {
NSLog(@"name:%@\\\\n body:%@\\\\n",message.name,message.body);
}
@end
以上就是WKWebView的基本使用，demo地址：https://github.com/MrZhaoCn/WKWebView.git