iOS ~ WKWebView 页面：加载HTML或其他

上面的导航栏是使用UIView写的，不是真正的 navigationBar
返回键和标题分别是一个UIButton和UILabel。

• 使用方法：

    WKWebViewController *userAgreementVC = [[WKWebViewController alloc] init];
    // HTML链接地址：
    [userAgreementVC loadWebURLSring:@"https://resource.policy.html"];
    // 标题title
    userAgreementVC.titleStr = @"高尔夫会员用户协议";

    [self.viewController.navigationController pushViewController:userAgreementVC animated:NO];

1、.h文件

//  github链接:https://github.com/XFIOSXiaoFeng/WKWebView

#import "GWBaseViewController.h"

@interface WKWebViewController : GWBaseViewController

/** 是否显示Nav */
@property (nonatomic,assign) BOOL isNavHidden;

/** 左上角返回键: NO 白色（基类颜色），YES 黑色 */
@property (nonatomic,assign) BOOL isLeftReturnColor;

/** 标题 */
@property (nonatomic,strong) NSString* titleStr;
/**
 加载纯外部链接网页

 @param string URL地址
 */
- (void)loadWebURLSring:(NSString *)string;

/**
 加载本地网页
 
 @param string 本地HTML文件名
 */
- (void)loadWebHTMLSring:(NSString *)string;

/**
 加载外部链接POST请求(注意检查 XFWKJSPOST.html 文件是否存在 )
 postData请求块 注意格式：@"\"username\":\"xxxx\",\"password\":\"xxxx\""
 
 @param string 需要POST的URL地址
 @param postData post请求块
 */
- (void)POSTWebURLSring:(NSString *)string postData:(NSString *)postData;


@end

2、.m文件

//
//  WKWebViewController.m
//  WKWebViewOC
//
//  Created by XiaoFeng on 2016/11/24.
//  Copyright © 2016年 XiaoFeng. All rights reserved.
//  QQ群: 384089763 欢迎加入
//  github链接: https://github.com/XFIOSXiaoFeng/WKWebView


#import "WKWebViewController.h"

#import <WebKit/WKWebView.h>
#import <WebKit/WebKit.h>

typedef enum{
    loadWebURLString = 0,
    loadWebHTMLString,
    POSTWebURLString,
}wkWebLoadType;

static void *WkwebBrowserContext = &WkwebBrowserContext;

@interface WKWebViewController ()<WKNavigationDelegate,WKUIDelegate,WKScriptMessageHandler,UINavigationControllerDelegate,UINavigationBarDelegate>

@property (nonatomic, strong) WKWebView *wkWebView;
//设置加载进度条
@property (nonatomic,strong) UIProgressView *progressView;
//仅当第一次的时候加载本地JS
@property(nonatomic,assign) BOOL needLoadJSPOST;
//网页加载的类型
@property(nonatomic,assign) wkWebLoadType loadType;
//保存的网址链接
@property (nonatomic, copy) NSString *URLString;
//保存POST请求体
@property (nonatomic, copy) NSString *postData;
//保存请求链接
@property (nonatomic)NSMutableArray* snapShotsArray;
//返回按钮
@property (nonatomic)UIBarButtonItem* customBackBarItem;
//关闭按钮
@property (nonatomic)UIBarButtonItem* closeButtonItem;

@end

@implementation WKWebViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    self.isNavHidden =NO;
    
    //加载web页面
    [self webViewloadURLType];
    
    //添加到主控制器上
    [self.view addSubview:self.wkWebView];
    
    //添加进度条
    [self.view addSubview:self.progressView];
    
    //添加右边刷新按钮
    UIBarButtonItem *roadLoad = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRefresh target:self action:@selector(roadLoadClicked)];
    self.navigationItem.rightBarButtonItem = roadLoad;
}

- (void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    
    if (_isNavHidden == YES) {
        self.navigationController.navigationBarHidden = YES;
        //创建一个高20的假状态栏
        UIView *statusBarView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.bounds.size.width, 20)];
        //设置成绿色
        statusBarView.backgroundColor=[UIColor whiteColor];
        // 添加到 navigationBar 上
        [self.view addSubview:statusBarView];
    }else{
        self.navigationController.navigationBarHidden = NO;
    }
}


- (void)roadLoadClicked{
    [self.wkWebView reload];
}

-(void)customBackItemClicked{
    if (self.wkWebView.goBack) {
        [self.wkWebView goBack];
    }else{
        [self.navigationController popViewControllerAnimated:YES];
    }
}
-(void)closeItemClicked{
    [self.navigationController popViewControllerAnimated:YES];
}

#pragma mark ================ 加载方式 ================

- (void)webViewloadURLType{
    switch (self.loadType) {
        case loadWebURLString:{
            //创建一个NSURLRequest 的对象
            NSURLRequest * Request_zsj = [NSURLRequest requestWithURL:[NSURL URLWithString:self.URLString] cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10];
            //加载网页
            [self.wkWebView loadRequest:Request_zsj];
            break;
        }
        case loadWebHTMLString:{
            [self loadHostPathURL:self.URLString];
            break;
        }
        case POSTWebURLString:{
            // JS发送POST的Flag，为真的时候会调用JS的POST方法
            self.needLoadJSPOST = YES;
            //POST使用预先加载本地JS方法的html实现，请确认WKJSPOST存在
            [self loadHostPathURL:@"WKJSPOST"];
            break;
        }
    }
}

- (void)loadHostPathURL:(NSString *)url{
    //获取JS所在的路径
    NSString *path = [[NSBundle mainBundle] pathForResource:url ofType:@"html"];
    //获得html内容
    NSString *html = [[NSString alloc] initWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil];
    //加载js
    [self.wkWebView loadHTMLString:html baseURL:[[NSBundle mainBundle] bundleURL]];
}

// 调用JS发送POST请求
- (void)postRequestWithJS {
    // 拼装成调用JavaScript的字符串
    NSString *jscript = [NSString stringWithFormat:@"post('%@',{%@});", self.URLString, self.postData];
    // 调用JS代码
    [self.wkWebView evaluateJavaScript:jscript completionHandler:^(id object, NSError * _Nullable error) {
    }];
}


- (void)loadWebURLSring:(NSString *)string{
    self.URLString = string;
    self.loadType = loadWebURLString;
}

- (void)loadWebHTMLSring:(NSString *)string{
    self.URLString = string;
    self.loadType = loadWebHTMLString;
}

- (void)POSTWebURLSring:(NSString *)string postData:(NSString *)postData{
    self.URLString = string;
    self.postData = postData;
    self.loadType = POSTWebURLString;
}

#pragma mark ================ 自定义返回/关闭按钮 ================

-(void)updateNavigationItems{
    if (self.wkWebView.canGoBack) {
        UIBarButtonItem *spaceButtonItem = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
        spaceButtonItem.width = -6.5;

        [self.navigationItem setLeftBarButtonItems:@[spaceButtonItem,self.customBackBarItem,self.closeButtonItem] animated:NO];
    }else{
        self.navigationController.interactivePopGestureRecognizer.enabled = YES;
        [self.navigationItem setLeftBarButtonItems:@[self.customBackBarItem]];
    }
}
//请求链接处理
-(void)pushCurrentSnapshotViewWithRequest:(NSURLRequest*)request{
    //    NSLog(@"push with request %@",request);
    NSURLRequest* lastRequest = (NSURLRequest*)[[self.snapShotsArray lastObject] objectForKey:@"request"];
    
    //如果url是很奇怪的就不push
    if ([request.URL.absoluteString isEqualToString:@"about:blank"]) {
        //        NSLog(@"about blank!! return");
        return;
    }
    //如果url一样就不进行push
    if ([lastRequest.URL.absoluteString isEqualToString:request.URL.absoluteString]) {
        return;
    }
    UIView* currentSnapShotView = [self.wkWebView snapshotViewAfterScreenUpdates:YES];
    [self.snapShotsArray addObject:
     @{@"request":request,@"snapShotView":currentSnapShotView}];
}

#pragma mark ================ WKNavigationDelegate ================

//这个是网页加载完成，导航的变化
-(void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{
    /*
     主意：这个方法是当网页的内容全部显示（网页内的所有图片必须都正常显示）的时候调用（不是出现的时候就调用），，否则不显示，或则部分显示时这个方法就不调用。
     */
    // 判断是否需要加载（仅在第一次加载）
    if (self.needLoadJSPOST) {
        // 调用使用JS发送POST请求的方法
        [self postRequestWithJS];
        // 将Flag置为NO（后面就不需要加载了）
        self.needLoadJSPOST = NO;
    }
    // 获取加载网页的标题
    self.titleLabel.text = self.titleStr;
    
    if (self.isLeftReturnColor) {
        [self.leftButton setImage:[UIImage imageNamed:@"web_back"] forState:UIControlStateNormal];
    }

    [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO];
//    [self updateNavigationItems];
}

//开始加载
-(void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation{
    //开始加载的时候，让加载进度条显示
    self.progressView.hidden = NO;
}

//内容返回时调用
-(void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation{}

//服务器请求跳转的时候调用
-(void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(WKNavigation *)navigation{}

//服务器开始请求的时候调用
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {
    
    switch (navigationAction.navigationType) {
        case WKNavigationTypeLinkActivated: {
            [self pushCurrentSnapshotViewWithRequest:navigationAction.request];
            break;
        }
        case WKNavigationTypeFormSubmitted: {
            [self pushCurrentSnapshotViewWithRequest:navigationAction.request];
            break;
        }
        case WKNavigationTypeBackForward: {
            break;
        }
        case WKNavigationTypeReload: {
            break;
        }
        case WKNavigationTypeFormResubmitted: {
            break;
        }
        case WKNavigationTypeOther: {
            [self pushCurrentSnapshotViewWithRequest:navigationAction.request];
            break;
        }
        default: {
            break;
        }
    }
    [self updateNavigationItems];
    decisionHandler(WKNavigationActionPolicyAllow);
}

// 内容加载失败时候调用
-(void)webView:(WKWebView *)webView didFailProvisionalNavigation:(WKNavigation *)navigation withError:(NSError *)error{
    NSLog(@"页面加载超时");
}

//跳转失败的时候调用
-(void)webView:(WKWebView *)webView didFailNavigation:(WKNavigation *)navigation withError:(NSError *)error{}

//进度条
-(void)webViewWebContentProcessDidTerminate:(WKWebView *)webView{}

#pragma mark ================ WKUIDelegate ================

// 获取js 里面的提示
-(void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler{
    
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"提示" message:message preferredStyle:UIAlertControllerStyleAlert];
    [alert addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
        completionHandler();
    }]];
    
    [self presentViewController:alert animated:YES completion:NULL];
}

// js 信息的交流
-(void)webView:(WKWebView *)webView runJavaScriptConfirmPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(BOOL))completionHandler{
    UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"提示" message:message 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];
}

// 交互。可输入的文本。
-(void)webView:(WKWebView *)webView runJavaScriptTextInputPanelWithPrompt:(NSString *)prompt defaultText:(NSString *)defaultText initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(NSString * _Nullable))completionHandler{
    
    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];
    
}

//KVO监听进度条
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
    
    if ([keyPath isEqualToString:NSStringFromSelector(@selector(estimatedProgress))] && object == self.wkWebView) {
        [self.progressView setAlpha:1.0f];
        BOOL animated = self.wkWebView.estimatedProgress > self.progressView.progress;
        [self.progressView setProgress:self.wkWebView.estimatedProgress animated:animated];
        
        // Once complete, fade out UIProgressView
        if(self.wkWebView.estimatedProgress >= 1.0f) {
            [UIView animateWithDuration:0.3f delay:0.3f options:UIViewAnimationOptionCurveEaseOut animations:^{
                [self.progressView setAlpha:0.0f];
            } completion:^(BOOL finished) {
                [self.progressView setProgress:0.0f animated:NO];
            }];
        }
    }
    else {
        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
    }
}

#pragma mark ================ WKScriptMessageHandler ================

//拦截执行网页中的JS方法
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{

    //服务器固定格式写法 window.webkit.messageHandlers.名字.postMessage(内容);
    //客户端写法 message.name isEqualToString:@"名字"]
    if ([message.name isEqualToString:@"WXPay"]) {
        NSLog(@"%@", message.body);
        //调用微信支付方法
//        [self WXPayWithParam:message.body];
    }
}

#pragma mark ================ 懒加载 ================

- (WKWebView *)wkWebView{
    if (!_wkWebView) {
        //设置网页的配置文件
        WKWebViewConfiguration * Configuration = [[WKWebViewConfiguration alloc]init];
        //允许视频播放
        Configuration.allowsAirPlayForMediaPlayback = YES;
        // 允许在线播放
        Configuration.allowsInlineMediaPlayback = YES;
        // 允许可以与网页交互，选择视图
        Configuration.selectionGranularity = YES;
        // web内容处理池
        Configuration.processPool = [[WKProcessPool alloc] init];
        //自定义配置,一般用于 js调用oc方法(OC拦截URL中的数据做自定义操作)
        WKUserContentController * UserContentController = [[WKUserContentController alloc]init];
        // 添加消息处理，注意：self指代的对象需要遵守WKScriptMessageHandler协议，结束时需要移除
        [UserContentController addScriptMessageHandler:self name:@"WXPay"];
        // 是否支持记忆读取
        Configuration.suppressesIncrementalRendering = YES;
        // 允许用户更改网页的设置
        Configuration.userContentController = UserContentController;
        _wkWebView = [[WKWebView alloc] initWithFrame:CGRectMake(0, k_Height_NavBar, SCREEN_WIDTH, SCREEN_HEIGHT) configuration:Configuration];
        _wkWebView.backgroundColor = [UIColor colorWithRed:240.0/255 green:240.0/255 blue:240.0/255 alpha:1.0];
        // 设置代理
        _wkWebView.navigationDelegate = self;
        _wkWebView.UIDelegate = self;
        //kvo 添加进度监控
        [_wkWebView addObserver:self forKeyPath:NSStringFromSelector(@selector(estimatedProgress)) options:0 context:WkwebBrowserContext];
        //开启手势触摸
        _wkWebView.allowsBackForwardNavigationGestures = YES;
        // 设置 可以前进 和 后退
        //适应你设定的尺寸
        [_wkWebView sizeToFit];
    }
    return _wkWebView;
}

-(UIBarButtonItem*)customBackBarItem{
    if (!_customBackBarItem) {
        UIImage* backItemImage = [[UIImage imageNamed:@"backItemImage"] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
        UIImage* backItemHlImage = [[UIImage imageNamed:@"backItemImage-hl"] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
        
        UIButton* backButton = [[UIButton alloc] init];
        [backButton setTitle:@"返回" forState:UIControlStateNormal];
        [backButton setTitleColor:self.navigationController.navigationBar.tintColor forState:UIControlStateNormal];
        [backButton setTitleColor:[self.navigationController.navigationBar.tintColor colorWithAlphaComponent:0.5] forState:UIControlStateHighlighted];
        [backButton.titleLabel setFont:[UIFont systemFontOfSize:17]];
        [backButton setImage:backItemImage forState:UIControlStateNormal];
        [backButton setImage:backItemHlImage forState:UIControlStateHighlighted];
        [backButton sizeToFit];
        
        [backButton addTarget:self action:@selector(customBackItemClicked) forControlEvents:UIControlEventTouchUpInside];
        _customBackBarItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];
    }
    return _customBackBarItem;
}

- (UIProgressView *)progressView{
    if (!_progressView) {
        _progressView = [[UIProgressView alloc]initWithProgressViewStyle:UIProgressViewStyleDefault];
        if (_isNavHidden == YES) {
            _progressView.frame = CGRectMake(0, 20, self.view.bounds.size.width, 3);
        }else{
            _progressView.frame = CGRectMake(0, k_Height_NavBar, self.view.bounds.size.width, 3);
        }
        // 设置进度条的色彩
        [_progressView setTrackTintColor:[UIColor colorWithRed:240.0/255 green:240.0/255 blue:240.0/255 alpha:1.0]];
        _progressView.progressTintColor = [UIColor greenColor];
    }
    return _progressView;
}

-(UIBarButtonItem*)closeButtonItem{
    if (!_closeButtonItem) {
        _closeButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"关闭" style:UIBarButtonItemStylePlain target:self action:@selector(closeItemClicked)];
    }
    return _closeButtonItem;
}

-(NSMutableArray*)snapShotsArray{
    if (!_snapShotsArray) {
        _snapShotsArray = [NSMutableArray array];
    }
    return _snapShotsArray;
}

-(void)viewWillDisappear:(BOOL)animated{
    [self.wkWebView.configuration.userContentController removeScriptMessageHandlerForName:@"WXPay"];
    [self.wkWebView setNavigationDelegate:nil];
    [self.wkWebView setUIDelegate:nil];
}

//注意，观察的移除
-(void)dealloc{
    [self.wkWebView removeObserver:self forKeyPath:NSStringFromSelector(@selector(estimatedProgress))];
}

@end