feat(android): Use addWebMessageListener where available

android/capacitor/build.gradle

@@ -4,6 +4,7 @@ ext {
     androidxCoordinatorLayoutVersion = project.hasProperty('androidxCoordinatorLayoutVersion') ? rootProject.ext.androidxCoordinatorLayoutVersion : '1.2.0'
     androidxCoreVersion = project.hasProperty('androidxCoreVersion') ? rootProject.ext.androidxCoreVersion : '1.8.0'
     androidxFragmentVersion = project.hasProperty('androidxFragmentVersion') ? rootProject.ext.androidxFragmentVersion : '1.4.1'
+    androidxWebkitVersion = project.hasProperty('androidxWebkitVersion') ? rootProject.ext.androidxWebkitVersion : '1.4.0'
     junitVersion = project.hasProperty('junitVersion') ? rootProject.ext.junitVersion : '4.13.2'
     androidxJunitVersion = project.hasProperty('androidxJunitVersion') ? rootProject.ext.androidxJunitVersion : '1.1.3'
     androidxEspressoCoreVersion = project.hasProperty('androidxEspressoCoreVersion') ? rootProject.ext.androidxEspressoCoreVersion : '3.4.0'
@@ -64,6 +65,7 @@ dependencies {
     implementation "androidx.activity:activity:$androidxActivityVersion"
     implementation "androidx.fragment:fragment:$androidxFragmentVersion"
     implementation "androidx.coordinatorlayout:coordinatorlayout:$androidxCoordinatorLayoutVersion"
+    implementation "androidx.webkit:webkit:$androidxWebkitVersion"
     testImplementation "junit:junit:$junitVersion"
     androidTestImplementation "androidx.test.ext:junit:$androidxJunitVersion"
     androidTestImplementation "androidx.test.espresso:espresso-core:$androidxEspressoCoreVersion"

android/capacitor/src/main/assets/native-bridge.js

@@ -384,10 +384,18 @@ const nativeBridge = (function (exports) {
                 }
                 return null;
             };
+            if (win === null || win === void 0 ? void 0 : win.androidBridge) {
+                win.androidBridge.onmessage = function (event) {
+                    returnResult(JSON.parse(event.data));
+                };
+            }
             /**
              * Process a response from the native layer.
              */
             cap.fromNative = result => {
+                returnResult(result);
+            };
+            const returnResult = (result) => {
                 var _a, _b;
                 if (cap.isLoggingEnabled && result.pluginId !== 'Console') {
                     cap.logFromNative(result);

android/capacitor/src/main/java/com/getcapacitor/Bridge.java

@@ -40,9 +40,11 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import org.apache.cordova.ConfigXmlParser;
 import org.apache.cordova.CordovaPreferences;
 import org.apache.cordova.CordovaWebView;
@@ -97,6 +99,7 @@ public class Bridge {
     private String appUrl;
     private String appUrlConfig;
     private HostMask appAllowNavigationMask;
+    private Set<String> allowedOriginRules = new HashSet<String>();
     // A reference to the main WebView for the app
     private final WebView webView;
     public final MockCordovaInterfaceImpl cordovaInterface;
@@ -186,6 +189,7 @@ private Bridge(
 
         // Initialize web view and message handler for it
         this.initWebView();
+        this.setAllowedOriginRules();
         this.msgHandler = new MessageHandler(this, webView, pluginManager);
 
         // Grab any intent info that our app was launched with
@@ -198,6 +202,25 @@ private Bridge(
         this.loadWebView();
     }
 
+    private void setAllowedOriginRules() {
+        String[] appAllowNavigationConfig = this.config.getAllowNavigation();
+        String authority = this.getHost();
+        String scheme = this.getScheme();
+        allowedOriginRules.add(scheme + "://" + authority);
+        if (this.getServerUrl() != null) {
+            allowedOriginRules.add(this.getServerUrl());
+        }
+        if (appAllowNavigationConfig != null) {
+            for (String allowNavigation : appAllowNavigationConfig) {
+                if (!allowNavigation.startsWith("http")) {
+                    allowedOriginRules.add("https://" + allowNavigation);
+                } else {
+                    allowedOriginRules.add(allowNavigation);
+                }
+            }
+        }
+    }
+
     public App getApp() {
         return app;
     }
@@ -207,14 +230,13 @@ private void loadWebView() {
         String[] appAllowNavigationConfig = this.config.getAllowNavigation();
 
         ArrayList<String> authorities = new ArrayList<>();
+
         if (appAllowNavigationConfig != null) {
             authorities.addAll(Arrays.asList(appAllowNavigationConfig));
         }
         this.appAllowNavigationMask = HostMask.Parser.parse(appAllowNavigationConfig);
-
         String authority = this.getHost();
         authorities.add(authority);
-
         String scheme = this.getScheme();
 
         localUrl = scheme + "://" + authority;
@@ -241,7 +263,6 @@ private void loadWebView() {
         if (appUrlPath != null && !appUrlPath.trim().isEmpty()) {
             appUrl += appUrlPath;
         }
-
         final boolean html5mode = this.config.isHTML5Mode();
 
         // Start the local web server
@@ -1267,6 +1288,10 @@ public HostMask getAppAllowNavigationMask() {
         return appAllowNavigationMask;
     }
 
+    public Set<String> getAllowedOriginRules() {
+        return allowedOriginRules;
+    }
+
     public BridgeWebViewClient getWebViewClient() {
         return this.webViewClient;
     }

android/capacitor/src/main/java/com/getcapacitor/MessageHandler.java

@@ -1,7 +1,12 @@
 package com.getcapacitor;
 
+import android.net.Uri;
 import android.webkit.JavascriptInterface;
 import android.webkit.WebView;
+import androidx.webkit.JavaScriptReplyProxy;
+import androidx.webkit.WebMessageCompat;
+import androidx.webkit.WebViewCompat;
+import androidx.webkit.WebViewFeature;
 import org.apache.cordova.PluginManager;
 
 /**
@@ -13,13 +18,31 @@ public class MessageHandler {
     private Bridge bridge;
     private WebView webView;
     private PluginManager cordovaPluginManager;
+    private JavaScriptReplyProxy javaScriptReplyProxy;
 
     public MessageHandler(Bridge bridge, WebView webView, PluginManager cordovaPluginManager) {
         this.bridge = bridge;
         this.webView = webView;
         this.cordovaPluginManager = cordovaPluginManager;
 
-        webView.addJavascriptInterface(this, "androidBridge");
+        WebViewCompat.WebMessageListener capListener = (view, message, sourceOrigin, isMainFrame, replyProxy) -> {
+            if (isMainFrame) {
+                postMessage(message.getData());
+                javaScriptReplyProxy = replyProxy;
+            } else {
+                Logger.warn("Plugin execution is allowed in Main Frame only");
+            }
+        };
+
+        if (WebViewFeature.isFeatureSupported(WebViewFeature.WEB_MESSAGE_LISTENER)) {
+            try {
+                WebViewCompat.addWebMessageListener(webView, "androidBridge", bridge.getAllowedOriginRules(), capListener);
+            } catch (Exception ex) {
+                webView.addJavascriptInterface(this, "androidBridge");
+            }
+        } else {
+            webView.addJavascriptInterface(this, "androidBridge");
+        }
     }
 
     /**
@@ -100,9 +123,13 @@ public void sendResponseMessage(PluginCall call, PluginResult successResult, Plu
 
             boolean isValidCallbackId = !call.getCallbackId().equals(PluginCall.CALLBACK_ID_DANGLING);
             if (isValidCallbackId) {
-                final String runScript = "window.Capacitor.fromNative(" + data.toString() + ")";
-                final WebView webView = this.webView;
-                webView.post(() -> webView.evaluateJavascript(runScript, null));
+                if (WebViewFeature.isFeatureSupported(WebViewFeature.WEB_MESSAGE_LISTENER) && javaScriptReplyProxy != null) {
+                    javaScriptReplyProxy.postMessage(data.toString());
+                } else {
+                    final String runScript = "window.Capacitor.fromNative(" + data.toString() + ")";
+                    final WebView webView = this.webView;
+                    webView.post(() -> webView.evaluateJavascript(runScript, null));
+                }
             } else {
                 bridge.getApp().fireRestoredResult(data);
             }

core/native-bridge.ts

@@ -457,10 +457,20 @@ const initBridge = (w: any): void => {
       return null;
     };
 
+    if (win?.androidBridge) {
+      win.androidBridge.onmessage = function (event) {
+        returnResult(JSON.parse(event.data));
+      };
+    }
+
     /**
      * Process a response from the native layer.
      */
     cap.fromNative = result => {
+      returnResult(result);
+    };
+
+    const returnResult = (result: any) => {
       if (cap.isLoggingEnabled && result.pluginId !== 'Console') {
         cap.logFromNative(result);
       }

core/src/definitions-internal.ts

@@ -188,6 +188,7 @@ export interface WindowCapacitor {
   WEBVIEW_SERVER_URL?: string;
   androidBridge?: {
     postMessage(data: string): void;
+    onmessage?: (event: { data: string }) => void;
   };
   webkit?: {
     messageHandlers?: {

ios/Capacitor/Capacitor/assets/native-bridge.js

@@ -384,10 +384,18 @@ const nativeBridge = (function (exports) {
                 }
                 return null;
             };
+            if (win === null || win === void 0 ? void 0 : win.androidBridge) {
+                win.androidBridge.onmessage = function (event) {
+                    returnResult(JSON.parse(event.data));
+                };
+            }
             /**
              * Process a response from the native layer.
              */
             cap.fromNative = result => {
+                returnResult(result);
+            };
+            const returnResult = (result) => {
                 var _a, _b;
                 if (cap.isLoggingEnabled && result.pluginId !== 'Console') {
                     cap.logFromNative(result);