wkwebview 代理介绍
iOS 8引入了一个新的框架——WebKit，之后变得好起来了。在WebKit框架中，有WKWebView可以替换UIKit的UIWebView和AppKit的WebView，而且提供了在两个平台可以一致使用的接口。
WebKit框架使得开发者可以在原生App中使用Nitro来提高网页的性能和表现，Nitro就是Safari的JavaScript引擎。下面举个🌰
代码中有详细的注释
//
// ViewController.m
// WKWebView01
//
// Created by njdby on 16/7/8.
// Copyright © 2016年 njdby. All rights reserved.
//
#import "ViewController.h"
#import <WebKit/WebKit.h>
@interface ViewController ()<WKUIDelegate, WKNavigationDelegate,WKScriptMessageHandler>
@property (nonatomic, strong) WKWebView *webView;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
WKWebViewConfiguration *config = [[WKWebViewConfiguration alloc] init];
// 设置偏好设置
config.preferences = [[WKPreferences alloc] init];
// 默认为0
config.preferences.minimumFontSize = 10;
// 默认认为YES
config.preferences.javaScriptEnabled = YES;
// 在iOS上默认为NO，表示不能自动通过窗口打开
config.preferences.javaScriptCanOpenWindowsAutomatically = NO;
// web内容处理池，由于没有属性可以设置，也没有方法可以调用，不用手动创建
config.processPool = [[WKProcessPool alloc] init];
// 通过JS与webview内容交互
config.userContentController = [[WKUserContentController alloc] init];
// 注入JS对象名称AppModel，当JS通过AppModel来调用时，
// 我们可以在WKScriptMessageHandler代理中接收到
[config.userContentController addScriptMessageHandler:self name:@"AppModel"];
self.webView = [[WKWebView alloc] initWithFrame:self.view.bounds
configuration:config];
[self.view addSubview:self.webView];
// 导航代理
self.webView.navigationDelegate = self;
// 与webview UI交互代理
self.webView.UIDelegate = self;
// [self.webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"https://www.baidu.com"]]];
NSURL *path = [[NSBundle mainBundle] URLForResource:@"test" withExtension:@"html"];
[self.webView loadRequest:[NSURLRequest requestWithURL:path]];
// 添加KVO监听
[self.webView addObserver:self
forKeyPath:@"loading"
options:NSKeyValueObservingOptionNew
context:nil];
[self.webView addObserver:self
forKeyPath:@"title"
options:NSKeyValueObservingOptionNew
context:nil];
[self.webView addObserver:self
forKeyPath:@"estimatedProgress"
options:NSKeyValueObservingOptionNew
context:nil];
}
#pragma mark - WKUIDelegate
#if __IPHONE_OS_VERSION_MAX_ALLOWED > __IPHONE_9_0
- (void)webViewDidClose:(WKWebView *)webView {
NSLog(@"%s", __FUNCTION__);
}
#endif
// 创建一个新的WebView（标签带有 target='_blank' 时，导致WKWebView无法加载点击后的网页的问题。）
- (WKWebView *)webView:(WKWebView *)webView createWebViewWithConfiguration:(WKWebViewConfiguration *)configuration forNavigationAction:(WKNavigationAction *)navigationAction windowFeatures:(WKWindowFeatures *)windowFeatures {
// 接口的作用是打开新窗口委托
WKFrameInfo *frameInfo = navigationAction.targetFrame;
if (![frameInfo isMainFrame]) {
[webView loadRequest:navigationAction.request];
}
return nil;
}
// 在JS端调用alert函数时，会触发此代理方法。
// JS端调用alert时所传的数据可以通过message拿到
// 在原生得到结果后，需要回调JS，是通过completionHandler回调
- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler {
NSLog(@"%s", __FUNCTION__);
UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"alert" message:@"JS调用alert" preferredStyle:UIAlertControllerStyleAlert];
[alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
completionHandler();
}]];
[self presentViewController:alert animated:YES completion:NULL];
NSLog(@"%@", message);
}
// JS端调用confirm函数时，会触发此方法
// 通过message可以拿到JS端所传的数据
// 在iOS端显示原生alert得到YES/NO后
// 通过completionHandler回调给JS端
- (void)webView:(WKWebView *)webView runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(BOOL result))completionHandler {
NSLog(@"%s", __FUNCTION__);
UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"confirm" message:@"JS调用confirm" preferredStyle:UIAlertControllerStyleAlert];
[alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
completionHandler(YES);
}]];
[alert addAction:[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
completionHandler(NO);
}]];
[self presentViewController:alert animated:YES completion:NULL];
NSLog(@"%@", message);
}
// JS端调用prompt函数时，会触发此方法
// 要求输入一段文本
// 在原生输入得到文本内容后，通过completionHandler回调给JS
- (void)webView:(WKWebView *)webView runJavaScriptTextInputPanelWithPrompt:(NSString *)prompt defaultText:(nullable NSString *)defaultText initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(NSString * __nullable result))completionHandler {
NSLog(@"%s", __FUNCTION__);
NSLog(@"%@", prompt);
UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"textinput" message:@"JS调用输入框" preferredStyle:UIAlertControllerStyleAlert];
[alert addTextFieldWithConfigurationHandler:^(UITextField * _Nonnull textField) {
textField.textColor = [UIColor redColor];
}];
[alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
completionHandler([[alert.textFields lastObject] text]);
}]];
[self presentViewController:alert animated:YES completion:NULL];
}
#pragma mark - WKNavigationDelegate
#pragma mark - WKNavigationDelegate
/**
* 在发送请求之前，决定是否跳转
*
* @param webView 实现该代理的
* @param navigationAction 当前navigation
* @param decisionHandler 是否调转block
*/
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {
NSString *hostname = navigationAction.request.URL.host.lowercaseString;
if (navigationAction.navigationType == WKNavigationTypeLinkActivated
&& ![hostname containsString:@".baidu.com"]) {
// 对于跨域，需要手动跳转
[[UIApplication sharedApplication] openURL:navigationAction.request.URL];
// 不允许web内跳转
decisionHandler(WKNavigationActionPolicyCancel);
} else {
self.progressView.alpha = 1.0;
decisionHandler(WKNavigationActionPolicyAllow);
}
NSLog(@"%s", __FUNCTION__);
}
/**
* 在收到响应后，决定是否跳转
*
* @param webView 实现该代理的webview
* @param navigationResponse 当前navigation
* @param decisionHandler 是否跳转block
*/
- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler {
// NSLog(@"%@",navigationResponse.response);
// 如果响应的地址是百度，则允许跳转
// if ([navigationResponse.response.URL.host.lowercaseString isEqual:@"www.baidu.com"]) {
//
// // 允许跳转
// decisionHandler(WKNavigationResponsePolicyAllow);
// return;
// }
// // 不允许跳转
// decisionHandler(WKNavigationResponsePolicyCancel);
decisionHandler(WKNavigationResponsePolicyAllow);
}
/**
* 页面开始加载时调用
*
* @param webView 实现该代理的webview
* @param navigation 当前navigation
*/
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(null_unspecified WKNavigation *)navigation {
NSLog(@"%s", __FUNCTION__);
}
/**
* 接收到服务器跳转请求之后调用
*
* @param webView 实现该代理的webview
* @param navigation 当前navigation
*/
- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(null_unspecified WKNavigation *)navigation {
NSLog(@"%s", __FUNCTION__);
}
/**
* 加载失败时调用
*
* @param webView 实现该代理的webview
* @param navigation 当前navigation
* @param error 错误
*/
- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(null_unspecified WKNavigation *)navigation withError:(NSError *)error {
NSLog(@"%s", __FUNCTION__);
}
/**
* 当内容开始返回时调用
*
* @param webView 实现该代理的webview
* @param navigation 当前navigation
*/
- (void)webView:(WKWebView *)webView didCommitNavigation:(null_unspecified WKNavigation *)navigation {