ios WKWebView js和OC交互

//
//  ViewController.m
//  oc_js_html
//
//  Created by apple on 2019/3/11.
//  Copyright © 2019年 suncere. All rights reserved.
//

#import "ViewController.h"
#import 
#import "Masonry.h"

@interface ViewController ()
@property(nonatomic,strong)WKWebView *webView;
@property(nonatomic,strong) WKWebViewConfiguration *wkWebConfig;

@end

@implementation ViewController

-(WKWebViewConfiguration *)wkWebConfig {
    if (!_wkWebConfig) {
        NSString *jScript = @"var meta = document.createElement('meta'); meta.setAttribute('name', 'viewport'); meta.setAttribute('content', 'width=device-width'); document.getElementsByTagName('head')[0].appendChild(meta);";
        WKUserScript *wkUScript = [[WKUserScript alloc] initWithSource:jScript injectionTime:WKUserScriptInjectionTimeAtDocumentEnd forMainFrameOnly:YES];
        
        WKUserContentController *wkUController = [[WKUserContentController alloc] init];
        [wkUController addUserScript:wkUScript];
        
        _wkWebConfig = [[WKWebViewConfiguration alloc] init];
        _wkWebConfig.userContentController = wkUController;
    }
    return _wkWebConfig;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    self.webView = [[WKWebView alloc] initWithFrame:CGRectZero configuration:self.wkWebConfig];
    [self loadWebView];
    
    self.webView.navigationDelegate = self;
    self.webView.UIDelegate = self;
    
    //开了支持滑动返回
    //self.webView.allowsBackForwardNavigationGestures = YES;
    [self.view addSubview:self.webView];
    
    [self.wkWebConfig.userContentController addScriptMessageHandler:self name:@"postMessage"];//添加js的方法
    
    [self.webView mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.right.top.bottom.equalTo(@0);
    }];
}

-(void)loadWebView {
    NSString *filePath = [[NSBundle mainBundle] pathForResource:@"index" ofType:@"html" inDirectory:@"www"];
    NSURL *pathURL = [NSURL fileURLWithPath:filePath];
    [self.webView loadRequest:[NSURLRequest requestWithURL:pathURL]];
}


#pragma mark - WKScriptMessageHandler

//实现js注入方法的协议方法
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message {
    if ([message.name isEqualToString:@"postMessage"]) {
        NSLog(@"%@", message.body);
    }
}

-(void)setLocation:(NSString *)str {
    NSString *jsStr = [NSString stringWithFormat:@"setLocation('%@')",str];
    [self.webView evaluateJavaScript:jsStr completionHandler:^(id _Nullable result, NSError * _Nullable error) {
        NSLog(@"%@----%@",result, error);
    }];
}

// 页面开始加载时调用
-(void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation{
    
}

// 当内容开始返回时调用
- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation{
    
}

// 页面加载完成之后调用
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{//这里修改导航栏的标题，动态改变
    //self.title = webView.title;

    NSString *injectionJSString = @"var script = document.createElement('meta');"
    "script.name = 'viewport';"
    "script.content=\"width=device-width, initial-scale=1.0,maximum-scale=1.0, minimum-scale=1.0, user-scalable=no\";"
    "document.getElementsByTagName('head')[0].appendChild(script);";
    [webView evaluateJavaScript:injectionJSString completionHandler:nil];
    [self setLocation:@"test"];
    
}

- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(null_unspecified WKNavigation *)navigation withError:(NSError *)error {
    NSLog(@"页面加载失败");
    //[SVProgressHUD showErrorWithStatus:@"页面加载失败,请重试..."];
    
}

// 接收到服务器跳转请求之后再执行
- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(WKNavigation *)navigation{
    
}

// 在收到响应后，决定是否跳转
- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler{
    
    WKNavigationResponsePolicy actionPolicy = WKNavigationResponsePolicyAllow;
    //这句是必须加上的，不然会异常
    decisionHandler(actionPolicy);
}

// 在发送请求之前，决定是否跳转
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler{
    WKNavigationActionPolicy actionPolicy = WKNavigationActionPolicyAllow;
    
    //这句是必须加上的，不然会异常
    decisionHandler(actionPolicy);
}

@end

js代码