[webview_flutter] Added possibility to activate the zoom webview Android - no-op on IOS (Android)

packages/webview_flutter/android/src/main/java/io/flutter/plugins/webviewflutter/FlutterWebView.java

@@ -195,6 +195,9 @@ private void applySettings(Map<String, Object> settings) {
 
           webView.setWebViewClient(webViewClient);
           break;
+        case "zoomEnabled":
+          updateZoomMode((boolean) settings.get(key));
+          break;
         default:
           throw new IllegalArgumentException("Unknown WebView setting: " + key);
       }
@@ -214,6 +217,14 @@ private void updateJsMode(int mode) {
     }
   }
 
+  private void updateZoomMode(boolean mode) {
+    webView.getSettings().setLoadWithOverviewMode(true);
+    webView.getSettings().setUseWideViewPort(true);
+    // Pop-up zoom controls disabled. This is a temporary stop because dialog is not responding to touch events.
+    webView.getSettings().setDisplayZoomControls(false);
+    webView.getSettings().setBuiltInZoomControls(mode);
+  }
+
   private void registerJavaScriptChannelNames(List<String> channelNames) {
     for (String channelName : channelNames) {
       webView.addJavascriptInterface(

packages/webview_flutter/example/lib/main.dart

@@ -44,6 +44,7 @@ class WebViewExample extends StatelessWidget {
       body: Builder(builder: (BuildContext context) {
         return WebView(
           initialUrl: 'https://flutter.dev',
+          zoomEnabled: true,
           javascriptMode: JavascriptMode.unrestricted,
           onWebViewCreated: (WebViewController webViewController) {
             _controller.complete(webViewController);

packages/webview_flutter/lib/webview_flutter.dart

@@ -117,6 +117,7 @@ class WebView extends StatefulWidget {
     this.navigationDelegate,
     this.gestureRecognizers,
     this.onPageFinished,
+    this.zoomEnabled = false,
   })  : assert(javascriptMode != null),
         super(key: key);
 
@@ -204,6 +205,10 @@ class WebView extends StatefulWidget {
   /// directly in the HTML has been loaded and code injected with
   /// [WebViewController.evaluateJavascript] can assume this.
   final PageFinishedCallback onPageFinished;
+
+  /// Enable/Disable zoom
+  /// Note: no-op on IOS
+  final bool zoomEnabled;
 
   @override
   State<StatefulWidget> createState() => _WebViewState();
@@ -324,22 +329,26 @@ class _WebSettings {
   _WebSettings({
     this.javascriptMode,
     this.hasNavigationDelegate,
+    this.zoomEnabled,
   });
 
   static _WebSettings fromWidget(WebView widget) {
     return _WebSettings(
       javascriptMode: widget.javascriptMode,
       hasNavigationDelegate: widget.navigationDelegate != null,
+      zoomEnabled: widget.zoomEnabled,
     );
   }
 
   final JavascriptMode javascriptMode;
   final bool hasNavigationDelegate;
+  final bool zoomEnabled;
 
   Map<String, dynamic> toMap() {
     return <String, dynamic>{
       'jsMode': javascriptMode.index,
       'hasNavigationDelegate': hasNavigationDelegate,
+      'zoomEnabled': zoomEnabled,
     };
   }
 
@@ -351,6 +360,9 @@ class _WebSettings {
     if (hasNavigationDelegate != newSettings.hasNavigationDelegate) {
       updates['hasNavigationDelegate'] = newSettings.hasNavigationDelegate;
     }
+    if (zoomEnabled != newSettings.zoomEnabled) {
+      updates['zoomEnabled'] = newSettings.zoomEnabled;
+    }
     return updates;
   }
 }