使用 AndroidX 增强 WebView 的能力

// Old code:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1) {
   WebView.startSafeBrowsing(appContext, callback);
}

// New code:
if (WebViewFeature.isFeatureSupported(WebViewFeature.START_SAFE_BROWSING)) {
   WebViewCompat.startSafeBrowsing(appContext, callback);
}

// WebViewCompat#startSafeBrowsing
public static void startSafeBrowsing(@NonNull Context context,
        @Nullable ValueCallback<Boolean> callback) {
    ApiFeature.O_MR1 feature = WebViewFeatureInternal.START_SAFE_BROWSING;
    if (feature.isSupportedByFramework()) {
        ApiHelperForOMR1.startSafeBrowsing(context, callback);
    } else if (feature.isSupportedByWebView()) {
        getFactory().getStatics().initSafeBrowsing(context, callback);
    } else {
        throw WebViewFeatureInternal.getUnsupportedOperationException();
    }
}

if (WebViewFeature.isFeatureSupported(WebViewFeature.PROXY_OVERRIDE)) {
    ProxyConfig proxyConfig = new ProxyConfig.Builder()
            .addProxyRule("localhost:7890") //添加要用于所有 URL 的代理
            .addProxyRule("localhost:1080") //优先级低于第一个代理，仅在上一个失败时应用
            .addDirect()                    //当前面的代理失败时，不使用代理直连
            .addBypassRule("www.baidu.com") //该网址不使用代理，直连服务
            .addBypassRule("*.cn")          //以.cn结尾的网址不使用代理
            .build();
    Executor executor = ...
    Runnable listener = ...
    ProxyController.getInstance().setProxyOverride(proxyConfig, executor, listener);
｝

// App (in Java)
WebMessageListener myListener = new WebMessageListener() {
  @Override
  public void onPostMessage(WebView view, WebMessageCompat message, Uri sourceOrigin,
           boolean isMainFrame, JavaScriptReplyProxy replyProxy) {
    // do something about view, message, sourceOrigin and isMainFrame.
    replyProxy.postMessage("Got it!");
  }
};

HashSet<String> allowedOriginRules = new HashSet<>(Arrays.asList("[https://example.com](https://example.com/)"));
// Add WebMessageListeners.

WebViewCompat.addWebMessageListener(webView, "replyObject", allowedOriginRules,myListener);

// Web page (in JavaScript)
myObject.onmessage = function(event) {
  // prints "Got it!" when we receive the app's response.
  console.log(event.data);
}
myObject.postMessage("I'm ready!");

// App (in Java)
WebMessageListener myListener = new WebMessageListener() {
  @Override
  public void onPostMessage(WebView view, WebMessageCompat message, Uri sourceOrigin,
           boolean isMainFrame, JavaScriptReplyProxy replyProxy) {
    // Communication is setup, send file data to web.
    if (WebViewFeature.isFeatureSupported(WebViewFeature.WEB_MESSAGE_ARRAY_BUFFER)) {
      // Suppose readFileData method is to read content from file.
      byte[] fileData = readFileData("myFile.dat");
      replyProxy.postMessage(fileData);
    }
  }
}

// Web page (in JavaScript)
myObject.onmessage = function(event) {
  if (event.data instanceof ArrayBuffer) {
    const data = event.data;  // Received file content from app.
    const dataView = new DataView(data);
    // Consume file content by using JavaScript DataView to access ArrayBuffer.
  }
}
myObject.postMessage("Setup!");

// Web page (in JavaScript)
const response = await fetch('example.jpg');
if (response.ok) {
    const imageData = await response.arrayBuffer();
    myObject.postMessage(imageData);
}

// App (in Java)
WebMessageListener myListener = new WebMessageListener() {
  @Override
  public void onPostMessage(WebView view, WebMessageCompat message, Uri sourceOrigin,
           boolean isMainFrame, JavaScriptReplyProxy replyProxy) {
    if (message.getType() == WebMessageCompat.TYPE_ARRAY_BUFFER) {
      byte[] imageData = message.getArrayBuffer();
      // do something like draw image on ImageView.
    }
  }
};

if(!JavaScriptSandbox.isSupported()){
return;
}
//连接到引擎
ListenableFuture<JavaScriptSandbox> jsSandboxFuture =
               JavaScriptSandbox.createConnectedInstanceAsync(context);
//创建上下文 上下文间有简单的数据隔离
JavaScriptIsolate jsIsolate = jsSandbox.createIsolate();
//执行函数 && 获取结果
final String code = "function sum(a, b) { let r = a + b; return r.toString(); }; sum(3, 4)";
ListenableFuture<String> resultFuture = jsIsolate.evaluateJavaScriptAsync(code);
String result = resultFuture.get(5, TimeUnit.SECONDS);
Futures.addCallback(resultFuture,
       new FutureCallback<String>() {
           @Override
           public void onSuccess(String result) {
               text.append(result);
           }
           @Override
           public void onFailure(Throwable t) {
               text.append(t.getMessage());
           }
       },
       mainThreadExecutor); //Wasm运行
final byte[] hello_world_wasm = {
   0x00 ,0x61 ,0x73 ,0x6d ,0x01 ,0x00 ,0x00 ,0x00 ,0x01 ,0x0a ,0x02 ,0x60 ,0x02 ,0x7f ,0x7f ,0x01,
   0x7f ,0x60 ,0x00 ,0x00 ,0x03 ,0x03 ,0x02 ,0x00 ,0x01 ,0x04 ,0x04 ,0x01 ,0x70 ,0x00 ,0x01 ,0x05,
   0x03 ,0x01 ,0x00 ,0x00 ,0x06 ,0x06 ,0x01 ,0x7f ,0x00 ,0x41 ,0x08 ,0x0b ,0x07 ,0x18 ,0x03 ,0x06,
   0x6d ,0x65 ,0x6d ,0x6f ,0x72 ,0x79 ,0x02 ,0x00 ,0x05 ,0x74 ,0x61 ,0x62 ,0x6c ,0x65 ,0x01 ,0x00,
   0x03 ,0x61 ,0x64 ,0x64 ,0x00 ,0x00 ,0x09 ,0x07 ,0x01 ,0x00 ,0x41 ,0x00 ,0x0b ,0x01 ,0x01 ,0x0a,
   0x0c ,0x02 ,0x07 ,0x00 ,0x20 ,0x00 ,0x20 ,0x01 ,0x6a ,0x0b ,0x02 ,0x00 ,0x0b,
};
final String jsCode = "android.consumeNamedDataAsArrayBuffer('wasm-1').then(" +
       "(value) => { return WebAssembly.compile(value).then(" +
       "(module) => { return new WebAssembly.Instance(module).exports.add(20, 22).toString(); }" +
       ")})";
boolean success = js.provideNamedData("wasm-1", hello_world_wasm);
if (success) {
    FluentFuture.from(js.evaluateJavaScriptAsync(jsCode))
           .transform(this::println, mainThreadExecutor)
           .catching(Throwable.class, e -> println(e.getMessage()), mainThreadExecutor);
} else {
   // the data chunk name has been used before, use a different name
}