主要实现两个功能
1.拦截http和https的请求并替换成缓存资源(兼容IOS10)
2.js<->Native的带参交互，参数可以直接是字典、数组、和字符串
1.拦截原理：
通过私有类WKBrowsingContextController 和让http和https执行私有API registerSchemeForCustomProtocol，
-(void)filtHTTP{
Class cls = NSClassFromString(@"WKBrowsingContextController");
SEL sel = NSSelectorFromString(@"registerSchemeForCustomProtocol:");
if ([(id)cls respondsToSelector:sel]) {
[(id)cls performSelector:sel withObject:@"http"];
[(id)cls performSelector:sel withObject:@"https"];
}
}
通过NSURLProtocol注册NSURLProtocol的派生类UrlRedirectionProtocol
[NSURLProtocol registerClass:[UrlRedirectionProtocol class]];
//适当时机并卸载以防止泄漏和不需要拦截时依然被拦截
[NSURLProtocol unregisterClass:[UrlRedirectionProtocol class]];
并在派生类实现url拦截并重定向本地url
+ (NSURLRequest *)canonicalRequestForRequest:(NSURLRequest *)request{
// NSLog(@"截获url : %@",request.URL.absoluteString);
__block NSMutableURLRequest *mutableReqeust = [request mutableCopy];
//截取重定向
[[UrlFiltManager shareInstance].urlFiltSet enumerateObjectsUsingBlock:^(NSString *host, BOOL * _Nonnull stop) {
if ([request.URL.absoluteString hasPrefix:host])
{
NSURL* proxyURL = [NSURL URLWithString:[UrlRedirectionProtocol generateProxyPath: request.URL.absoluteString host:host]];
// NSLog(@"替换为url : %@",proxyURL.absoluteString);
if ([[NSFileManager defaultManager]fileExistsAtPath:proxyURL.absoluteString]) {
mutableReqeust = [NSMutableURLRequest requestWithURL: proxyURL];
*stop = YES;
}
}
}];
return mutableReqeust;
}
重写startLoading方法实现本地资源重载
- (void)startLoading {
NSMutableURLRequest *mutableReqeust = [[self request] mutableCopy];
// 标识该request已经处理过了，防止无限循环
[NSURLProtocol setProperty:@YES forKey:FilteredKey inRequest:mutableReqeust];
if ([self checkNeedLoadingLocalData]) {
__weak __typeof(&*self)weakSelf = self;
dispatch_async(dispatch_get_global_queue(0, 0), ^{
__strong __typeof(&*weakSelf)strongSelf = weakSelf;
NSFileHandle *file = [NSFileHandle fileHandleForReadingAtPath:strongSelf.request.URL.absoluteString];
NSData *data = [file readDataToEndOfFile];
[file closeFile];
//3.拼接响应Response
NSInteger dataLength = data.length?:3;
NSString *mimeType = [strongSelf getMIMETypeWithCAPIAtFilePath:strongSelf.request.URL.absoluteString];
NSHTTPURLResponse *response = [strongSelf jointResponseWithData:data
dataLength:dataLength
mimeType:mimeType
requestUrl:strongSelf.request.URL
statusCode:dataLength?200:404
httpVersion:@"HTTP/1.1"];
//4.响应
[[strongSelf client] URLProtocol:strongSelf didReceiveResponse:response cacheStoragePolicy:NSURLCacheStorageNotAllowed];
[[strongSelf client] URLProtocol:strongSelf didLoadData:data];
[[strongSelf client] URLProtocolDidFinishLoading:strongSelf];
});
}
else {
self.connection = [NSURLConnection connectionWithRequest:mutableReqeust delegate:self];
}
}
2.js交互原理：
通过向WKUserContentController的handler添加方法以供js调用
-(void)registOCMethods:(NSSet *)methods{
for (NSString *method in methods) {
[self.userContentController addScriptMessageHandler:self name:method];
}
}
/*js调用oc方法通过回调执行，oc收到回调可以解析WKScriptMessage中的name(被js调用的oc方法名)和body（js传到oc消息提）并转换成oc方法
*/
#pragma mark -- WKScriptMessageHandler
-(void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{
SEL selector =NSSelectorFromString([message.name stringByAppendingString:@":"]);
IMP imp = [self methodForSelector:selector];
void (*func)(id, SEL,id) = (void *)imp;
if ([self respondsToSelector:selector]) {
func(self, selector,message.body);
}
}
js通过window.webkit.messageHandlers.方法名.postMessage(消息体)调用oc并传参
//js中的方法，js调oc的getAppEnv方法
function getAppInfo()
{
//获取app的运行环境
alert("获取appinfo");
window.webkit.messageHandlers.getAppEnv.postMessage("");
}
//oc中的方法 js调oc 的getAppEnv方法
- (void)getAppEnv:(NSString *)env{
NSString *version = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleShortVersionString"];
NSString *shareResult = [NSString stringWithFormat:@"appEnvResult('%@')",version];
//OC调用JS返回结果
[self.wkWebView evaluateJavaScript:shareResult completionHandler:^(id _Nullable result, NSError * _Nullable error) {
NSLog(@"%@", error);
}];
}
//js中的方法，js接收到oc调用appEnvResult方法和appEnv参数
function appEnvResult(appEnv)
{
//获取到app的运行环境是 appEnv
var content = "app回调数据" + appEnv;
alert(content);
}
//oc调js通过wkwebview的api调用js
- (void)evaluateJavaScript:(NSString *)javaScriptString completionHandler:(void (^ _Nullable)(_Nullable id, NSError * _Nullable error))completionHandler;
[self.wkWebView evaluateJavaScript:@"js方法名('参数1','参数2','参数3',参数4)" completionHandler:^(id _Nullable result, NSError * _Nullable error) {
NSLog(@"%@", error);
}];
-（void)ocCallJs{
NSString *version = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleShortVersionString"];
NSString *shareResult = [NSString stringWithFormat:@"appEnvResult('%@')",version];
//OC调用JS
[self.wkWebView evaluateJavaScript:shareResult completionHandler:^(id _Nullable result, NSError * _Nullable error) {
NSLog(@"%@", error);
}];
}
//oc调js传对象，可以讲字典和数组转换成json并替换"""成"'"传给js，js可以接受不了到的就直接是js对象了
//js中的方法 调用app分享并带一个字典参数
function callShare() {
var shareInfo ={"title": "标题", "content": "内容", "shareUrl": "http://www.xxx.com","shareIco":"http://upload/xxxx"};
// Joy.share(shareInfo)
window.webkit.messageHandlers.Share.postMessage(shareInfo);
}
//oc中的方法“share”被js调用传回参数dic字典对象
- (void)Share:(NSDictionary *)dic{
if (![dic isKindOfClass:[NSDictionary class]]) {
return;
}
NSString *title = [dic objectForKey:@"title"];
NSString *content = [dic objectForKey:@"content"];
NSString *url = [dic objectForKey:@"shareUrl"];
//在这里写分享操作的代码
NSLog(@"要分享了哦😯");
//OC反馈给JS分享结果
NSError * error = nil;
NSData * jsonData = [NSJSONSerialization dataWithJSONObject:dic options:NSJSONWritingPrettyPrinted error:&error];
NSString * jsonStr = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
NSString *replaceStr = [jsonStr stringByReplacingOccurrencesOfString:@"\"" withString:@"\'"];
NSString *JSResult = [NSString stringWithFormat:@"shareResult('%@','%@','%@',%@)",title,content,url,replaceStr];
//OC调用JS
[self.wkWebView evaluateJavaScript:JSResult completionHandler:^(id _Nullable result, NSError * _Nullable error) {
NSLog(@"%@", error);
}];
//js接收oc方法并收到3个字符串参数和一个dic字典对象
function shareResult(channel_id,share_channel,share_url,dic) {
// var content = "app回调数据" + channel_id+","+share_channel+","+share_url;
var content = dic['title'] + dic['content'] + dic['shareUrl'];
alert(content);
document.getElementById("shareResult").value = content;
}
我们可以把js调用oc和oc调用js的函数写成一个或多个category以实现不同模块的js<->native调用
比如我的wkwebview放到了一个WebVC的控制器里,然后把交互事件放到不同的category里，然后根据实际需要使用
@interface WebVC (JSNative)
@end
@implementation WebVC (JSNative)
- (void)Share:(NSDictionary *)dic{
}
- (void)ShareVideo:(NSDictionary *)dic{
}
@end
@interface WebVC (Media)
@end
@implementation WebVC (Media)
- (void)openAlbum:(NSDictionary *)dic{
}
- (void) openCamera:(NSDictionary *)dic{
}
- (void) openQRScan:(NSDictionary *)dic{
}
@end
测试，可以搭建一个简易服务器并把资源文件放进去以供下载解压使用，这里用python
cd /Users/joymake/Desktop/h5service
//启动服务器，这里默认启动8000端口
python -m SimpleHTTPServer
//如果是模拟器地址用http://127.0.0.1:8000(demo里用的这个地址)就可以了，如果用的真机而资源包放在服务器上，那么地址需要改成服务器地址
ifconfig可用来查看当前服务器ip地址
启动本地服务.png
截图不知道为什么传上去后变这么大，知道的可以告诉我一下
demo文件结构
image.png
image.png
flutter资源
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