creator-webview与Android交互

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title: creator-webview与Android交互
categories: Cocos2dx
tags: [cocos2dx, creator, webview, 交互]
date: 2024-03-23 13:17:20
comments: false
mathjax: true
toc: true

creator-webview与Android交互

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前篇

• Android：你要的WebView与 JS 交互方式 都在这里了 - https://cloud.tencent.com/developer/article/1394361

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java 调用 js

• 使用 WebView.evaluateJavascript 执行 js 代码

  String callStr = String.format("window['java2js'](`%s`, `%s`)", funcName, jsonMsg);
  WebViewIns.evaluateJavascript(callStr, null);
  

  如果要透传数据结构或 json, 最好用 base64 加密一下, 然后在 js 中再解密出来, 以保证这些数据不会破会 js 代码的结构

  一般跨语言的交互中, 我都会使用 base64 去加密数据使之变成正常的字符串

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js 调用 java

1. 使用 WebView.addJavascriptInterface(Object, String); 映射对象和方法到 js 中一个变量, 例如:

   public static class JsUtils {@JavascriptInterfacepublic void call(String funcName, String jsonMsg) { // 具体多少个参数对上 js 即可...}
   }WebViewIns.addJavascriptInterface(new JsUtils(), "gJavaObj");
   

2. 直接使用 gJavaObj 对象即可

   gJavaObj.call(funcName, jsonMsg);
   

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加载 js 代码

• 使用 WebView.loadUrl

  String bdg = "js 代码";
  WebView.loadUrl("javascript:" + bdg);
  

• js 代码书写有严格的要求, 例如:

  // 1. 一定要以这种 执行方法 的方式初始化
  // 2. 语句结尾要加 ;, 不然报错 Invalid left-hand side expression in postfix operation
  // 3. 注释必须清楚掉
  (function() {window.cm = {};window.java2js = function(f, m) {var oldCb = window.cm[f];if (oldCb) oldCb(window.atob(m));window.cm[f] = null;};window.WebViewJavascriptBridge = {init: function() { },registerHandler: function() { },callHandler: function(f, m, c) {window.cm[f] = c;gJavaObj.call(f, m);},};document.dispatchEvent(new Event("WebViewJavascriptBridgeReady"));
  })()

  • 可以使用 uglyjs 把代码压缩成一行

    String bdg = "window.cm={},window.java2js=function(f,m){var oldCb=window.cm[f];oldCb&&oldCb(window.atob(m)),window.cm[f]=null},window.WebViewJavascriptBridge={init:function(){},registerHandler:function(){},callHandler:function(f,m,c){window.cm[f]=c,gJavaObj.call(f,m)}},document.dispatchEvent(new Event(\"WebViewJavascriptBridgeReady\"));"

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完整的 java, html 代码

java

• 代码

  import android.annotation.SuppressLint;
  import android.app.Activity;
  import android.app.AlertDialog;
  import android.net.http.SslError;
  import android.util.Base64;
  import android.view.ViewGroup;
  import android.webkit.JavascriptInterface;
  import android.webkit.SslErrorHandler;
  import android.webkit.WebResourceRequest;
  import android.webkit.WebResourceResponse;
  import android.webkit.WebSettings;
  import android.webkit.WebView;
  import android.webkit.WebViewClient;
  import android.widget.LinearLayout;
  import android.widget.RelativeLayout;import java.io.ByteArrayInputStream;
  import java.nio.charset.StandardCharsets;
  import java.util.Date;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.function.Consumer;public class WebviewHelper {public static WebviewHelper instance = null;private RelativeLayout mLayoutRoot;private WebView mWebview;private static Map<String, BridgeHandler> mJsCb = new HashMap<>();public static void showWebview(final Activity activity, final String url, final ActivityMgr.CodeRunnable task) {closeWebview(activity, () -> {instance = new WebviewHelper();instance.show(activity, url);if (task != null) {task.run(ActivityMgr.Ok, "");}});}public static void closeWebview(final Activity activity, final Runnable task) {activity.runOnUiThread(() -> {if (instance != null) {instance.destroy();}if (task != null) {task.run();}});}public static boolean goBack() {ActivityMgr.Act.moveTaskToBack(true);return false;}@SuppressLint("SetJavaScriptEnabled")public void show(Activity activity, final String url) {final RelativeLayout rLayout = new RelativeLayout(activity);mLayoutRoot = rLayout;RelativeLayout.LayoutParams rParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.MATCH_PARENT);LinearLayout.LayoutParams lParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);final WebView wv = new WebView(activity);wv.setWebViewClient(new WebviewClientHelper());mWebview = wv;wv.setLayoutParams(lParams);rLayout.addView(wv);activity.addContentView(rLayout, rParams);mWebview.addJavascriptInterface(new JsUtils(), "gJavaObj");//AndroidtoJS类对象映射到js的test对象wv.loadUrl(url);// 设置webviewWebSettings settings = wv.getSettings();settings.setJavaScriptCanOpenWindowsAutomatically(true);settings.setJavaScriptEnabled(true);settings.setDomStorageEnabled(true);settings.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK); // 有缓存就使用缓存settings.setSupportZoom(false);settings.setBuiltInZoomControls(true);}public static void regHandler(String name, BridgeHandler bh) {mJsCb.put(name, bh);}private void destroy() {if (mWebview != null) {mWebview.destroy();mWebview = null;}if (mLayoutRoot != null) {ViewGroup vg = (ViewGroup) mLayoutRoot.getParent();vg.removeView(mLayoutRoot);mLayoutRoot = null;}instance = null;}public interface BridgeHandler {void handler(String var1, Consumer<String> var2);}public static class JsUtils {@JavascriptInterfacepublic void call(String funcName, String jsonMsg) {BridgeHandler bh = mJsCb.get(funcName);if (bh == null) {ActivityMgr.E("no func: %s", funcName);return;}bh.handler(jsonMsg, (result) -> {try {// 交互是需要 base64 处理一下result = Base64.encodeToString((result != null ? result : "").getBytes(StandardCharsets.UTF_8), Base64.DEFAULT);String callStr = String.format("window['java2js'](`%s`, `%s`)", funcName, result);instance.mWebview.evaluateJavascript(callStr, null);} catch (Exception e) {e.printStackTrace();}});}}public static class WebviewClientHelper extends WebViewClient {public boolean isLoadBdg = false;@Overridepublic void onPageFinished(WebView view, String url) {if (!isLoadBdg) {String bdg = "window.cm={},window.java2js=function(f,m){var oldCb=window.cm[f];oldCb&&oldCb(window.atob(m)),window.cm[f]=null},window.WebViewJavascriptBridge={init:function(){},registerHandler:function(){},callHandler:function(f,m,c){window.cm[f]=c,gJavaObj.call(f,m)}},document.dispatchEvent(new Event(\"WebViewJavascriptBridgeReady\"));";view.loadUrl("javascript:" + bdg);isLoadBdg = true;}super.onPageFinished(view, url);}}
  }
  

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html

• 代码

  <!DOCTYPE html>
  <html>
  <head><script>document.addEventListener('WebViewJavascriptBridgeReady', function() {console.log("--- WebViewJavascriptBridgeReady");},false);function js2java() {console.log("--- js2java");// gJavaObj.hello("Hello Terry")var funcName = "StartInfo"var jsonMsg = "World 002"window.WebViewJavascriptBridge.callHandler(funcName, jsonMsg, function(responseData) {console.log("--- responseData:", responseData);})}console.log("--- web loaded");</script><title>Test Webview</title>
  </head><body><div id="mydiv"><br /><br /><button onclick="js2java()"> js2java </button></div>
  </body>
  </html>
  

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