iOS WebViewJavascriptBridge的使用

主要作用

OC引用

pod "WebViewJavascriptBridge"

OC中的代码示例

- (void)viewDidLoad {
[super viewDidLoad];

UIWebView *webView = [[UIWebView alloc] initWithFrame:self.view.bounds];
[self.view addSubview:webView];

NSString *htmlPath = [[NSBundle mainBundle] pathForResource:@"test" ofType:@"html"];
NSString *appHtml = [NSString stringWithContentsOfFile:htmlPath encoding:NSUTF8StringEncoding error:nil];
NSURL *baseURL = [NSURL fileURLWithPath:htmlPath];
[webView loadHTMLString:appHtml baseURL:baseURL];

// 开启日志
[WebViewJavascriptBridge enableLogging];

// 给哪个webview建立JS与OjbC的沟通桥梁
self.bridge = [WebViewJavascriptBridge bridgeForWebView:webView];
[self.bridge setWebViewDelegate:self];
[self renderButtons:webView];

// JS主动调用OjbC的方法
// 这是JS会调用getUserIdFromObjC方法，这是OC注册给JS调用的
// JS需要回调，当然JS也可以传参数过来。data就是JS所传的参数，不一定需要传
// OC端通过responseCallback回调JS端，JS就可以得到所需要的数据
[self.bridge registerHandler:@"getUserIdFromObjC" handler:^(id data, WVJBResponseCallback responseCallback) {
NSLog(@"js call getUserIdFromObjC, data from js is ncsjndjsn%@", data);
if (responseCallback) {
// 反馈给JS
responseCallback(@{@"userId": @"123456"});
}
}];
[self.bridge registerHandler:@"getBlogNameFromObjC" handler:^(id data, WVJBResponseCallback responseCallback) {
NSLog(@"js call getBlogNameFromObjC, data from js is %@", data);
if (responseCallback) {
// 反馈给JS
responseCallback(@{@"blogName": @"标哥的技术博客"});
}
}];

[self.bridge callHandler:@"getUserInfos" data:@{@"name": @"标哥"} responseCallback:^(id responseData) {
NSLog(@"from js: %@", responseData);
}];
}
- (void)webViewDidStartLoad:(UIWebView *)webView {
NSLog(@"webViewDidStartLoad");
}
- (void)webViewDidFinishLoad:(UIWebView *)webView {
NSLog(@"webViewDidFinishLoad");
}
- (void)renderButtons:(UIWebView*)webView {
UIFont* font = [UIFont fontWithName:@"HelveticaNeue" size:12.0];

UIButton *callbackButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[callbackButton setTitle:@"打开博文" forState:UIControlStateNormal];
[callbackButton addTarget:self action:@selector(onOpenBlogArticle:) forControlEvents:UIControlEventTouchUpInside];
[self.view insertSubview:callbackButton aboveSubview:webView];
callbackButton.frame = CGRectMake(10, 400, 100, 35);
callbackButton.titleLabel.font = font;

UIButton* reloadButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[reloadButton setTitle:@"刷新webview" forState:UIControlStateNormal];
[reloadButton addTarget:webView action:@selector(reload) forControlEvents:UIControlEventTouchUpInside];
[self.view insertSubview:reloadButton aboveSubview:webView];
reloadButton.frame = CGRectMake(110, 400, 100, 35);
reloadButton.titleLabel.font = font;
}
- (void)onOpenBlogArticle:(id)sender {
// 调用打开本demo的博文
[self.bridge callHandler:@"openWebviewBridgeArticle" data:nil];
}

JS中的调用

/*这段代码是固定的，必须要放到js中*/
function setupWebViewJavascriptBridge(callback) {
if (window.WebViewJavascriptBridge) { return callback(WebViewJavascriptBridge); }
if (window.WVJBCallbacks) { return window.WVJBCallbacks.push(callback); }
window.WVJBCallbacks = [callback];
var WVJBIframe = document.createElement('iframe');
WVJBIframe.style.display = 'none';
WVJBIframe.src = 'wvjbscheme://__BRIDGE_LOADED__';
document.documentElement.appendChild(WVJBIframe);
setTimeout(function() { document.documentElement.removeChild(WVJBIframe) }, 0)
}
/*与OC交互的所有JS方法都要放在此处注册，才能调用通过JS调用OC或者让OC调用这里的JS*/
setupWebViewJavascriptBridge(function(bridge) {
var uniqueId = 1
function log(message, data) {
var log = document.getElementById('log')
var el = document.createElement('div')
el.className = 'logLine'
el.innerHTML = uniqueId++ + '. ' + message + ':<br/>' + JSON.stringify(data)
if (log.children.length) {
log.insertBefore(el, log.children[0])
} else {
log.appendChild(el)
}
}
/* Initialize your app here */

/*我们在这注册一个js调用OC的方法，不带参数，且不用ObjC端反馈结果给JS：打开本demo对应的博文*/
bridge.registerHandler('openWebviewBridgeArticle', function() {
log("openWebviewBridgeArticle was called with by ObjC")
})
/*JS给ObjC提供公开的API，在ObjC端可以手动调用JS的这个API。接收ObjC传过来的参数，且可以回调ObjC*/
bridge.registerHandler('getUserInfos', function(data, responseCallback) {
log("Get user information from ObjC: ", data)
responseCallback({'userId': '123456', 'blog': '标哥的技术博客'})
})

/*JS给ObjC提供公开的API，ObjC端通过注册，就可以在JS端调用此API时，得到回调。ObjC端可以在处理完成后，反馈给JS，这样写就是在载入页面完成时就先调用*/
bridge.callHandler('getUserIdFromObjC', function(responseData) {
log("JS call ObjC's getUserIdFromObjC function, and js received response:", responseData)
})

document.getElementById('blogId').onclick = function (e) {
log('js call objc: getBlogNameFromObjC')
bridge.callHandler('getBlogNameFromObjC', {'blogURL': 'http://www.henishuo.com'}, function(response) {
log('JS got response', response)
})
}
})