2019-03-22

iOS WKWebView 远端h5优先加载本地资源

前言：UIWebView调用远端h5页面，优先加载本地图片、js、css等资源，解决办法就是对请求进行拦截。

服务端代码放在本文后面

客户端需要对NSURLProtocol 的自定义类进行注册，那么所有的webview 对http请求都会被他拦截到；

首先自定义NSURLProtocol类

#import <Foundation/Foundation.h>

#import <CoreFoundation/CoreFoundation.h>

#import <MobileCoreServices/MobileCoreServices.h>

@interface NSURLProtocolCustom : NSURLProtocol

@end

#import "NSURLProtocolCustom.h"

static NSString* const FilteredKey = @"FilteredKey";

@implementation NSURLProtocolCustom

+ (BOOL)canInitWithRequest:(NSURLRequest *)request

{

NSString *extension = request.URL.pathExtension;

BOOL isSource = [@[@"png", @"jpeg", @"gif", @"jpg", @"js", @"css"] indexOfObjectPassingTest:^BOOL(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {

return [extension compare:obj options:NSCaseInsensitiveSearch] == NSOrderedSame;

}] != NSNotFound;

return [NSURLProtocol propertyForKey:FilteredKey inRequest:request] == nil && isSource;

}

+ (NSURLRequest *)canonicalRequestForRequest:(NSURLRequest *)request

{

return request;

}

- (void)startLoading

{

NSString *fileName = [super.request.URL.absoluteString componentsSeparatedByString:@"/"].lastObject;

NSLog(@"fileName is %@",fileName);

//这里是获取本地资源路径如:png,js等

NSString *path = [[NSBundle mainBundle] pathForResource:fileName ofType:nil];

if (!path) {

[self sendResponseWithData:[NSData data] mimeType:nil];

return;

}

//根据路径获取MIMEType

CFStringRef pathExtension = (__bridge_retained CFStringRef)[path pathExtension];

CFStringRef type = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, pathExtension, NULL);

CFRelease(pathExtension);

//The UTI can be converted to a mime type:

NSString *mimeType = (__bridge_transfer NSString *)UTTypeCopyPreferredTagWithClass(type, kUTTagClassMIMEType);

if (type != NULL)

CFRelease(type);

//加载本地资源

NSData *data = [NSData dataWithContentsOfFile:path];

[self sendResponseWithData:data mimeType:mimeType];

}

- (void)stopLoading

{

NSLog(@"stopLoading, something went wrong!");

}

- (void)sendResponseWithData:(NSData *)data mimeType:(nullable NSString *)mimeType

{

// 这里需要用到MIMEType

NSURLResponse *response = [[NSURLResponse alloc] initWithURL:super.request.URL

MIMEType:mimeType

expectedContentLength:-1

textEncodingName:nil];

//硬编码开始嵌入本地资源到web中

[[self client] URLProtocol:self didReceiveResponse:response cacheStoragePolicy:NSURLCacheStorageNotAllowed];

[[self client] URLProtocol:self didLoadData:data];

[[self client] URLProtocolDidFinishLoading:self];

}

@end

其次实现对类的注册

#import "CSWebView.h"

#import <WebKit/WebKit.h>

#import "NSURLProtocolCustom.h"

@interface CSWebView ()<WKNavigationDelegate,WKUIDelegate,WKScriptMessageHandler>

@property (nonatomic, strong) WKWebView *wkWebView;

@end

@implementation CSWebView

- (void)viewDidLoad {

[super viewDidLoad];

//1.设置背景颜色

self.view.backgroundColor = [UIColor whiteColor];

//2.注册

[NSURLProtocol registerClass:[NSURLProtocolCustom class]];

//3.实现拦截功能，这个是核心

Class cls = NSClassFromString(@"WKBrowsingContextController");

SEL sel = NSSelectorFromString(@"registerSchemeForCustomProtocol:");

if ([(id)cls respondsToSelector:sel]) {

#pragma clang diagnostic push

#pragma clang diagnostic ignored "-Warc-performSelector-leaks"

[(id)cls performSelector:sel withObject:@"http"];

[(id)cls performSelector:sel withObject:@"https"];

#pragma clang diagnostic pop

}

//4.添加WKWebView

[self addWKWebView];

}

#pragma mark - WKWebView(IOS8以上使用)

#pragma mark 添加WKWebView

- (void)addWKWebView

{

//1.创建配置项

WKWebViewConfiguration *config = [[WKWebViewConfiguration alloc] init];

config.selectionGranularity = WKSelectionGranularityDynamic;

//1.1 设置偏好

config.preferences = [[WKPreferences alloc] init];

config.preferences.minimumFontSize = 10;

config.preferences.javaScriptEnabled = YES;

//1.1.1 默认是不能通过JS自动打开窗口的，必须通过用户交互才能打开

config.preferences.javaScriptCanOpenWindowsAutomatically = NO;

config.processPool = [[WKProcessPool alloc] init];

//1.2 通过JS与webview内容交互配置

config.userContentController = [[WKUserContentController alloc] init];

[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;

//2.添加WKWebView

WKWebView *wkWebView = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0, [UIApplication sharedApplication].keyWindow.bounds.size.width, [UIApplication sharedApplication].keyWindow.bounds.size.height) configuration:config];

wkWebView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth ;

wkWebView.UIDelegate = self;

wkWebView.navigationDelegate = self;

_urlStr = [_urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSURL *url = [NSURL URLWithString:_urlStr];

[wkWebView loadRequest:[NSURLRequest requestWithURL:url]];

//[wkWebView loadRequest: [[NSURLRequest alloc] initWithURL:[NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"app" ofType:@"html"]]]];

[self.view addSubview:wkWebView];

_wkWebView = wkWebView;

//3.注册js方法

[config.userContentController addScriptMessageHandler:self name:@"webViewApp"];

}

- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{

//接受传过来的消息从而决定app调用的方法

NSDictionary *dict = message.body;

NSString *method = [dict objectForKey:@"method"];

if ([method isEqualToString:@"hello"]) {

[self hello:[dict objectForKey:@"param1"]];

}else if ([method isEqualToString:@"Call JS"]){

[self callJS];

}else if ([method isEqualToString:@"Call JS Msg"]){

[self callJSMsg:[dict objectForKey:@"param1"]];

}

- (void)hello:(NSString *)param{

NSLog(@"hello");

}

- (void)callJS{

NSLog(@"callJS");

}

- (void)callJSMsg:(NSString *)msg{

NSLog(@"callJSMsg");

}

//WKNavigationDelegate

// 页面开始加载时调用

- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation {// 类似UIWebView的 -webViewDidStartLoad:

NSLog(@"didStartProvisionalNavigation");

[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;

}

// 当内容开始返回时调用

- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation {

NSLog(@"didCommitNavigation");

}

// 页面加载完成之后调用

- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation { // 类似UIWebView 的－webViewDidFinishLoad:

NSLog(@"didFinishNavigation");

//[self resetControl];

if (webView.title.length > 0) {

self.title = webView.title;

}

// 页面加载失败时调用

- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(WKNavigation *)navigation withError:(NSError *)error {

// 类似 UIWebView 的- webView:didFailLoadWithError:

NSLog(@"didFailProvisionalNavigation");

}

// 在收到响应后，决定是否跳转

- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler {

decisionHandler(WKNavigationResponsePolicyAllow);

}

// 在发送请求之前，决定是否跳转

- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction*)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler {

// 类似 UIWebView 的 -webView: shouldStartLoadWithRequest: navigationType:

NSLog(@"decidePolicyForNavigationAction %@",navigationAction.request);

// NSString *url = [navigationAction.request.URL.absoluteString stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

// NSString *url = navigationAction.request.URL.absoluteString;

decisionHandler(WKNavigationActionPolicyAllow);

}

// 接收到服务器跳转请求之后调用

- (void)webView:(WKWebView *)webView didReceiveServerRedirectForProvisionalNavigation:(WKNavigation *)navigation{

NSLog(@"didReceiveServerRedirectForProvisionalNavigation");

}

//- (void)webView:(WKWebView *)webView didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition, NSURLCredential *))completionHandler {

// completionHandler(NSURLSessionAuthChallengePerformDefaultHandling,internal);

//}

//WKUIDelegate

- (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

//[self createNewWebViewWithURL:webView.URL.absoluteString config:Web];

return _wkWebView;

}

- (void)webView:(WKWebView *)webView runJavaScriptAlertPanelWithMessage:(NSString *)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(void))completionHandler

{ // js 里面的alert实现，如果不实现，网页的alert函数无效

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:message

message:nil

preferredStyle:UIAlertControllerStyleAlert];

[alertController addAction:[UIAlertAction actionWithTitle:@"确定"

style:UIAlertActionStyleCancel

handler:^(UIAlertAction *action) {

completionHandler();

}]];

[self presentViewController:alertController animated:YES completion:^{

}];

}

// js 里面的alert实现，如果不实现，网页的alert函数无效

- (void)webView:(WKWebView *)webView runJavaScriptConfirmPanelWithMessage:(NSString*)message initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(BOOL))completionHandler {

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:message

message:nil

preferredStyle:UIAlertControllerStyleAlert];

[alertController addAction:[UIAlertAction actionWithTitle:@"确定"

style:UIAlertActionStyleDefault

handler:^(UIAlertAction *action) {

completionHandler(YES);

}]];

[alertController addAction:[UIAlertAction actionWithTitle:@"取消"

style:UIAlertActionStyleCancel

handler:^(UIAlertAction *action){

completionHandler(NO);

}]];

[self presentViewController:alertController animated:YES completion:^{}];

}

- (void)webView:(WKWebView *)webView runJavaScriptTextInputPanelWithPrompt:(NSString *)prompt defaultText:(NSString *)defaultText initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void(^)(NSString *))completionHandler {

completionHandler(@"Client Not handler");

}

- (void)showAlert:(NSString *)content Title:(NSString *)title{

UIAlertController *alertController = [UIAlertController alertControllerWithTitle:title

message:content

preferredStyle:UIAlertControllerStyleAlert];

[alertController addAction:[UIAlertAction actionWithTitle:@"确定"

style:UIAlertActionStyleCancel

handler:^(UIAlertAction *action) {

[self.navigationController popToRootViewControllerAnimated:YES];

}]];

[self presentViewController:alertController animated:YES completion:^{

}];

}

@end

服务端代码

<!DOCTYPE html>

<html>

<head>

<title>测试iOS与JS之间的互调</title>

{

font-size: 40px;

}

</style>

</head>

<body>

<h1>Test how to use Objective-C call js</h1>

</div>

<div>

</div>

<div>

</div>

</body>

</html>

本地js文件

function calliOS(Msg) {

var message = {

'method' : 'hello',

'param1' : Msg,

};

window.webkit.messageHandlers.webViewApp.postMessage(message);

}

function callJS() {

var message = {

'method' : 'Call JS',

};

window.webkit.messageHandlers.webViewApp.postMessage(message);

}

function callJSMsg(Msg) {

var message = {

'method' : 'Call JS Msg',

'param1' : Msg,

};

window.webkit.messageHandlers.webViewApp.postMessage(message);

}

function jsFunc() {

alert('Hello World');

}

iOS WKWebView 远端h5优先加载本地资源_IOS开发-织梦者

WKWebView实现网页静态资源优先从本地加载 - JackLee18 - CSDN博客

iOS WKWebView 远端h5优先加载本地资源 - AFun_day的博客 - CSDN博客