From c05e0e3963bd8d7be8348ce9dd22836fc2587231 Mon Sep 17 00:00:00 2001
From: Lorenzo Pichilli <pichillilorenzo@gmail.com>
Date: Thu, 12 Dec 2019 16:28:05 +0100
Subject: [PATCH] updated DropDown workaround: load it as soon as possible and
 load also for iframes where possibile (same origin)

---
 .idea/misc.xml                                |   2 +-
 .idea/workspace.xml                           | 131 +--
 README.md                                     |   2 +-
 .../InAppWebView/InAppWebView.java            | 834 +++++++++---------
 .../InAppWebView/InAppWebViewClient.java      |   7 +-
 lib/src/webview_options.dart                  |   1 +
 6 files changed, 491 insertions(+), 486 deletions(-)

diff --git a/.idea/misc.xml b/.idea/misc.xml
index bfa5e6bb..eac9d8a9 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -35,7 +35,7 @@
       </value>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" project-jdk-name="Android API 24 Platform" project-jdk-type="Android SDK" />
+  <component name="ProjectRootManager" version="2" project-jdk-name="Android API 28 Platform" project-jdk-type="Android SDK" />
   <component name="ProjectType">
     <option name="id" value="io.flutter" />
   </component>
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 85e1f47a..9995527d 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -16,9 +16,13 @@
   <component name="ChangeListManager">
     <list default="true" id="9b41f7a2-a71e-4923-91fb-249d7815b3e7" name="Default" comment="">
       <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/README.md" beforeDir="false" afterPath="$PROJECT_DIR$/README.md" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebView.java" beforeDir="false" afterPath="$PROJECT_DIR$/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebView.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebViewClient.java" beforeDir="false" afterPath="$PROJECT_DIR$/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebViewClient.java" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/example/ios/.symlinks/plugins/flutter_inappwebview/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/example/ios/.symlinks/plugins/flutter_inappwebview/.idea/workspace.xml" afterDir="false" />
       <change beforePath="$PROJECT_DIR$/example/ios/.symlinks/plugins/flutter_inappwebview/example/lib/main.dart" beforeDir="false" afterPath="$PROJECT_DIR$/example/ios/.symlinks/plugins/flutter_inappwebview/example/lib/main.dart" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/example/lib/main.dart" beforeDir="false" afterPath="$PROJECT_DIR$/example/lib/main.dart" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/lib/src/webview_options.dart" beforeDir="false" afterPath="$PROJECT_DIR$/lib/src/webview_options.dart" afterDir="false" />
     </list>
     <ignored path="$PROJECT_DIR$/.dart_tool/" />
     <ignored path="$PROJECT_DIR$/.idea/" />
@@ -35,14 +39,14 @@
   <component name="DefaultGradleProjectSettings">
     <option name="isMigrated" value="true" />
   </component>
-  <component name="ExecutionTargetManager" SELECTED_TARGET="Pixel_3_XL_API_24" />
+  <component name="ExecutionTargetManager" SELECTED_TARGET="LGH870776aa626" />
   <component name="FileEditorManager">
     <leaf SIDE_TABS_SIZE_LIMIT_KEY="300">
       <file pinned="false" current-in-tab="true">
         <entry file="file://$PROJECT_DIR$/example/lib/main.dart">
           <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="481">
-              <caret line="78" column="1" selection-start-line="78" selection-start-column="1" selection-end-line="78" selection-end-column="1" />
+            <state relative-caret-position="224">
+              <caret line="64" column="27" lean-forward="true" selection-start-line="64" selection-start-column="27" selection-end-line="64" selection-end-column="27" />
               <folding>
                 <element signature="e#0#20#0" expanded="true" />
               </folding>
@@ -65,8 +69,8 @@
       <file pinned="false" current-in-tab="false">
         <entry file="file://$PROJECT_DIR$/lib/src/webview_options.dart">
           <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="373">
-              <caret line="81" column="46" selection-start-line="81" selection-start-column="46" selection-end-line="81" selection-end-column="46" />
+            <state relative-caret-position="328">
+              <caret line="412" column="102" lean-forward="true" selection-start-line="412" selection-start-column="5" selection-end-line="412" selection-end-column="102" />
               <folding>
                 <element signature="e#0#17#0" expanded="true" />
               </folding>
@@ -98,7 +102,7 @@
       <file pinned="false" current-in-tab="false">
         <entry file="file://$PROJECT_DIR$/lib/src/in_app_browser.dart">
           <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="4575">
+            <state relative-caret-position="535">
               <caret line="315" column="50" selection-start-line="315" selection-start-column="50" selection-end-line="315" selection-end-column="50" />
               <folding>
                 <element signature="e#0#20#0" expanded="true" />
@@ -110,8 +114,13 @@
       <file pinned="false" current-in-tab="false">
         <entry file="file://$PROJECT_DIR$/README.md">
           <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="6180">
-              <caret line="412" column="3" selection-start-line="412" selection-start-column="3" selection-end-line="412" selection-end-column="21" />
+            <state relative-caret-position="48">
+              <caret line="412" column="372" selection-start-line="412" selection-start-column="372" selection-end-line="412" selection-end-column="372" />
+              <folding>
+                <element signature="e#0#20#0" expanded="true" />
+                <element signature="e#0#39#0" expanded="true" />
+                <element signature="e#0#39#0" expanded="true" />
+              </folding>
             </state>
           </provider>
         </entry>
@@ -137,7 +146,6 @@
   </component>
   <component name="FindInProjectRecents">
     <findStrings>
-      <find>_staticChannel</find>
       <find>defa</find>
       <find>InAppWebViewStatic</find>
       <find>removeFromSuperview</find>
@@ -167,6 +175,7 @@
       <find>\n</find>
       <find>dropDownWorkaroundEnabled</find>
       <find>debuggingEnabled</find>
+      <find>\n&quot; +</find>
     </findStrings>
     <replaceStrings>
       <replace>activity.getPreferences(0)</replace>
@@ -176,6 +185,7 @@
       <replace>Event fired</replace>
       <replace>flutterInAppWebViewPlatformReady</replace>
       <replace>flutter_inappwebview</replace>
+      <replace>&quot; +</replace>
     </replaceStrings>
     <dirStrings>
       <dir>$PROJECT_DIR$/example/android</dir>
@@ -254,39 +264,6 @@
       <foldersAlwaysOnTop value="true" />
     </navigator>
     <panes>
-      <pane id="ProjectPane">
-        <subPane>
-          <expand>
-            <path>
-              <item name="flutter_inappwebview" type="b2602c69:ProjectViewProjectNode" />
-              <item name="flutter_inappwebview" type="462c0819:PsiDirectoryNode" />
-            </path>
-            <path>
-              <item name="flutter_inappwebview" type="b2602c69:ProjectViewProjectNode" />
-              <item name="flutter_inappwebview" type="462c0819:PsiDirectoryNode" />
-              <item name="lib" type="462c0819:PsiDirectoryNode" />
-            </path>
-            <path>
-              <item name="flutter_inappwebview" type="b2602c69:ProjectViewProjectNode" />
-              <item name="flutter_inappwebview" type="462c0819:PsiDirectoryNode" />
-              <item name="lib" type="462c0819:PsiDirectoryNode" />
-              <item name="src" type="462c0819:PsiDirectoryNode" />
-            </path>
-          </expand>
-          <select />
-        </subPane>
-      </pane>
-      <pane id="Scope">
-        <subPane subId="Project Files">
-          <expand>
-            <path>
-              <item name="Root" type="cbb8eebc:String" user="Root" />
-              <item name="flutter_inappbrowser" type="cbb8eebc:String" user="flutter_inappbrowser" />
-            </path>
-          </expand>
-          <select />
-        </subPane>
-      </pane>
       <pane id="PackagesPane" />
       <pane id="AndroidView">
         <subPane>
@@ -317,6 +294,39 @@
           <select />
         </subPane>
       </pane>
+      <pane id="Scope">
+        <subPane subId="Project Files">
+          <expand>
+            <path>
+              <item name="Root" type="cbb8eebc:String" user="Root" />
+              <item name="flutter_inappbrowser" type="cbb8eebc:String" user="flutter_inappbrowser" />
+            </path>
+          </expand>
+          <select />
+        </subPane>
+      </pane>
+      <pane id="ProjectPane">
+        <subPane>
+          <expand>
+            <path>
+              <item name="flutter_inappwebview" type="b2602c69:ProjectViewProjectNode" />
+              <item name="flutter_inappwebview" type="462c0819:PsiDirectoryNode" />
+            </path>
+            <path>
+              <item name="flutter_inappwebview" type="b2602c69:ProjectViewProjectNode" />
+              <item name="flutter_inappwebview" type="462c0819:PsiDirectoryNode" />
+              <item name="lib" type="462c0819:PsiDirectoryNode" />
+            </path>
+            <path>
+              <item name="flutter_inappwebview" type="b2602c69:ProjectViewProjectNode" />
+              <item name="flutter_inappwebview" type="462c0819:PsiDirectoryNode" />
+              <item name="lib" type="462c0819:PsiDirectoryNode" />
+              <item name="src" type="462c0819:PsiDirectoryNode" />
+            </path>
+          </expand>
+          <select />
+        </subPane>
+      </pane>
     </panes>
   </component>
   <component name="PropertiesComponent">
@@ -466,7 +476,7 @@
     </todo-panel>
   </component>
   <component name="ToolWindowManager">
-    <frame x="0" y="23" width="1920" height="1057" extended-state="6" />
+    <frame x="0" y="23" width="1920" height="1057" extended-state="0" />
     <editor active="true" />
     <layout>
       <window_info content_ui="combo" id="Project" order="0" sideWeight="0.6177474" visible="true" weight="0.1368477" />
@@ -480,7 +490,7 @@
       <window_info id="Resources Explorer" order="8" />
       <window_info anchor="bottom" id="Message" order="0" />
       <window_info anchor="bottom" id="Find" order="1" weight="0.32745314" />
-      <window_info active="true" anchor="bottom" id="Run" order="2" sideWeight="0.49478307" visible="true" weight="0.44455957" />
+      <window_info active="true" anchor="bottom" id="Run" order="2" sideWeight="0.49478307" visible="true" weight="0.38445595" />
       <window_info anchor="bottom" id="Debug" order="3" weight="0.34196892" />
       <window_info anchor="bottom" id="Cvs" order="4" weight="0.25" />
       <window_info anchor="bottom" id="Inspection" order="5" weight="0.4" />
@@ -855,9 +865,16 @@
         </state>
       </provider>
     </entry>
+    <entry file="file://$PROJECT_DIR$/CHANGELOG.md">
+      <provider selected="true" editor-type-id="text-editor">
+        <state relative-caret-position="180">
+          <caret line="12" column="34" selection-start-line="12" selection-start-column="34" selection-end-line="12" selection-end-column="34" />
+        </state>
+      </provider>
+    </entry>
     <entry file="file://$PROJECT_DIR$/lib/src/in_app_browser.dart">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="4575">
+        <state relative-caret-position="535">
           <caret line="315" column="50" selection-start-line="315" selection-start-column="50" selection-end-line="315" selection-end-column="50" />
           <folding>
             <element signature="e#0#20#0" expanded="true" />
@@ -867,22 +884,20 @@
     </entry>
     <entry file="file://$PROJECT_DIR$/README.md">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="6180">
-          <caret line="412" column="3" selection-start-line="412" selection-start-column="3" selection-end-line="412" selection-end-column="21" />
-        </state>
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/CHANGELOG.md">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="180">
-          <caret line="12" column="34" selection-start-line="12" selection-start-column="34" selection-end-line="12" selection-end-column="34" />
+        <state relative-caret-position="48">
+          <caret line="412" column="372" selection-start-line="412" selection-start-column="372" selection-end-line="412" selection-end-column="372" />
+          <folding>
+            <element signature="e#0#20#0" expanded="true" />
+            <element signature="e#0#39#0" expanded="true" />
+            <element signature="e#0#39#0" expanded="true" />
+          </folding>
         </state>
       </provider>
     </entry>
     <entry file="file://$PROJECT_DIR$/lib/src/webview_options.dart">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="373">
-          <caret line="81" column="46" selection-start-line="81" selection-start-column="46" selection-end-line="81" selection-end-column="46" />
+        <state relative-caret-position="328">
+          <caret line="412" column="102" lean-forward="true" selection-start-line="412" selection-start-column="5" selection-end-line="412" selection-end-column="102" />
           <folding>
             <element signature="e#0#17#0" expanded="true" />
           </folding>
@@ -891,8 +906,8 @@
     </entry>
     <entry file="file://$PROJECT_DIR$/example/lib/main.dart">
       <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="481">
-          <caret line="78" column="1" selection-start-line="78" selection-start-column="1" selection-end-line="78" selection-end-column="1" />
+        <state relative-caret-position="224">
+          <caret line="64" column="27" lean-forward="true" selection-start-line="64" selection-start-column="27" selection-end-line="64" selection-end-column="27" />
           <folding>
             <element signature="e#0#20#0" expanded="true" />
           </folding>
diff --git a/README.md b/README.md
index 7e76340a..438c5c59 100644
--- a/README.md
+++ b/README.md
@@ -410,7 +410,7 @@ Instead, on the `onLoadStop` WebView event, you can use `callHandler` directly:
 * `hardwareAcceleration`: Boolean value to enable Hardware Acceleration in the WebView.
 * `supportMultipleWindows`: Sets whether the WebView whether supports multiple windows.
 * `regexToCancelSubFramesLoading`: Regular expression used by `shouldOverrideUrlLoading` event to cancel navigation for frames that are not the main frame. If the url request of a subframe matches the regular expression, then the request of that subframe is canceled.
-* `dropDownWorkaroundEnabled`: Enable a temporary workaround for html dropdowns (`<select>` tags) (available on Android 19+). It requires **JavaScript enabled**. It attempts to block click events for the dropdowns creating a custom `<div>` layer over the dropdown to intercept user's clicks. The default value is `false`.
+* `dropDownWorkaroundEnabled`: Enable a temporary workaround for html dropdowns (`<select>` tags) (available on Android 19+). It requires **JavaScript enabled**. It attempts to block click events for the dropdowns creating a custom `<div>` layer over the dropdown to intercept user's clicks. This workaround is applied as soon as the web page fires the `DOMContentLoaded` JavaScript event. The default value is `false`.
 
 ##### `InAppWebView` iOS-specific options
 
diff --git a/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebView.java b/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebView.java
index dcf390b9..f62047fa 100644
--- a/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebView.java
+++ b/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebView.java
@@ -515,455 +515,445 @@ final public class InAppWebView extends InputAwareWebView {
           "})(window.fetch);";
 
   // Android API 19+
+  // ResizeSensor: https://github.com/marcj/css-element-queries/blob/master/src/ResizeSensor.js
   static final String dropDownWorkaroundJS = "(function() {" +
-          "  var uuid = 0;" +
-          "  function prepare() {" +
-          "    if (typeof window === \"undefined\") {" +
-          "      return null;" +
-          "    }" +
-          "    var globalWindow =" +
-          "      typeof window != \"undefined\" && window.Math == Math" +
-          "        ? window" +
-          "        : typeof self != \"undefined\" && self.Math == Math" +
-          "        ? self" +
-          "        : Function(\"return this\")();" +
-          "    var requestAnimationFrame =" +
-          "      globalWindow.requestAnimationFrame ||" +
-          "      globalWindow.mozRequestAnimationFrame ||" +
-          "      globalWindow.webkitRequestAnimationFrame ||" +
-          "      function(fn) {" +
-          "        return globalWindow.setTimeout(fn, 20);" +
-          "      };" +
-          "    function forEachElement(elements, callback) {" +
-          "      var elementsType = Object.prototype.toString.call(elements);" +
-          "      var isCollectionTyped =" +
-          "        \"[object Array]\" === elementsType ||" +
-          "        \"[object NodeList]\" === elementsType ||" +
-          "        \"[object HTMLCollection]\" === elementsType ||" +
-          "        \"[object Object]\" === elementsType ||" +
-          "        (\"undefined\" !== typeof jQuery && elements instanceof jQuery) ||" +
-          "        (\"undefined\" !== typeof Elements && elements instanceof Elements);" +
-          "      var i = 0," +
-          "        j = elements.length;" +
-          "      if (isCollectionTyped) {" +
-          "        for (; i < j; i++) {" +
-          "          callback(elements[i]);" +
+          "  function dropDownWorkaround(window, document) {" +
+          "    var uuid = 0;" +
+          "    function prepare() {" +
+          "      if (typeof window === 'undefined') {" +
+          "        return null;" +
+          "      }" +
+          "      var globalWindow =" +
+          "        typeof window != 'undefined' && window.Math == Math" +
+          "          ? window" +
+          "          : typeof self != 'undefined' && self.Math == Math" +
+          "          ? self" +
+          "          : Function('return this')();" +
+          "      var requestAnimationFrame =" +
+          "        globalWindow.requestAnimationFrame ||" +
+          "        globalWindow.mozRequestAnimationFrame ||" +
+          "        globalWindow.webkitRequestAnimationFrame ||" +
+          "        function(fn) {" +
+          "          return globalWindow.setTimeout(fn, 20);" +
+          "        };" +
+          "      function forEachElement(elements, callback) {" +
+          "        var elementsType = Object.prototype.toString.call(elements);" +
+          "        var isCollectionTyped =" +
+          "          '[object Array]' === elementsType ||" +
+          "          '[object NodeList]' === elementsType ||" +
+          "          '[object HTMLCollection]' === elementsType ||" +
+          "          '[object Object]' === elementsType ||" +
+          "          ('undefined' !== typeof jQuery && elements instanceof jQuery) ||" +
+          "          ('undefined' !== typeof Elements && elements instanceof Elements);" +
+          "        var i = 0," +
+          "          j = elements.length;" +
+          "        if (isCollectionTyped) {" +
+          "          for (; i < j; i++) {" +
+          "            callback(elements[i]);" +
+          "          }" +
+          "        } else {" +
+          "          callback(elements);" +
           "        }" +
-          "      } else {" +
-          "        callback(elements);" +
           "      }" +
-          "    }" +
-          "    function getElementSize(element) {" +
-          "      if (!element.getBoundingClientRect) {" +
+          "      function getElementSize(element) {" +
+          "        if (!element.getBoundingClientRect) {" +
+          "          return {" +
+          "            width: element.offsetWidth," +
+          "            height: element.offsetHeight" +
+          "          };" +
+          "        }" +
+          "        var rect = element.getBoundingClientRect();" +
           "        return {" +
-          "          width: element.offsetWidth," +
-          "          height: element.offsetHeight" +
+          "          width: Math.round(rect.width)," +
+          "          height: Math.round(rect.height)" +
           "        };" +
           "      }" +
-          "" +
-          "      var rect = element.getBoundingClientRect();" +
-          "      return {" +
-          "        width: Math.round(rect.width)," +
-          "        height: Math.round(rect.height)" +
-          "      };" +
-          "    }" +
-          "    function setStyle(element, style) {" +
-          "      Object.keys(style).forEach(function(key) {" +
-          "        element.style[key] = style[key];" +
-          "      });" +
-          "    }" +
-          "    var ResizeSensor = function(element, callback) {" +
-          "      var lastAnimationFrame = 0;" +
-          "      function EventQueue() {" +
-          "        var q = [];" +
-          "        this.add = function(ev) {" +
-          "          q.push(ev);" +
-          "        };" +
-          "" +
-          "        var i, j;" +
-          "        this.call = function(sizeInfo) {" +
-          "          for (i = 0, j = q.length; i < j; i++) {" +
-          "            q[i].call(this, sizeInfo);" +
-          "          }" +
-          "        };" +
-          "" +
-          "        this.remove = function(ev) {" +
-          "          var newQueue = [];" +
-          "          for (i = 0, j = q.length; i < j; i++) {" +
-          "            if (q[i] !== ev) newQueue.push(q[i]);" +
-          "          }" +
-          "          q = newQueue;" +
-          "        };" +
-          "" +
-          "        this.length = function() {" +
-          "          return q.length;" +
-          "        };" +
+          "      function setStyle(element, style) {" +
+          "        Object.keys(style).forEach(function(key) {" +
+          "          element.style[key] = style[key];" +
+          "        });" +
           "      }" +
-          "      function attachResizeEvent(element, resized) {" +
-          "        if (!element) return;" +
-          "        if (element.resizedAttached) {" +
+          "      var ResizeSensor = function(element, callback) {" +
+          "        var lastAnimationFrame = 0;" +
+          "        function EventQueue() {" +
+          "          var q = [];" +
+          "          this.add = function(ev) {" +
+          "            q.push(ev);" +
+          "          };" +
+          "          var i, j;" +
+          "          this.call = function(sizeInfo) {" +
+          "            for (i = 0, j = q.length; i < j; i++) {" +
+          "              q[i].call(this, sizeInfo);" +
+          "            }" +
+          "          };" +
+          "          this.remove = function(ev) {" +
+          "            var newQueue = [];" +
+          "            for (i = 0, j = q.length; i < j; i++) {" +
+          "              if (q[i] !== ev) newQueue.push(q[i]);" +
+          "            }" +
+          "            q = newQueue;" +
+          "          };" +
+          "          this.length = function() {" +
+          "            return q.length;" +
+          "          };" +
+          "        }" +
+          "        function attachResizeEvent(element, resized) {" +
+          "          if (!element) return;" +
+          "          if (element.resizedAttached) {" +
+          "            element.resizedAttached.add(resized);" +
+          "            return;" +
+          "          }" +
+          "          element.resizedAttached = new EventQueue();" +
           "          element.resizedAttached.add(resized);" +
+          "          element.resizeSensor = document.createElement('div');" +
+          "          element.resizeSensor.dir = 'ltr';" +
+          "          element.resizeSensor.className = 'resize-sensor';" +
+          "          var style = {" +
+          "            pointerEvents: 'none'," +
+          "            position: 'absolute'," +
+          "            left: '0px'," +
+          "            top: '0px'," +
+          "            right: '0px'," +
+          "            bottom: '0px'," +
+          "            overflow: 'hidden'," +
+          "            zIndex: '-1'," +
+          "            visibility: 'hidden'," +
+          "            maxWidth: '100%'" +
+          "          };" +
+          "          var styleChild = {" +
+          "            position: 'absolute'," +
+          "            left: '0px'," +
+          "            top: '0px'," +
+          "            transition: '0s'" +
+          "          };" +
+          "          setStyle(element.resizeSensor, style);" +
+          "          var expand = document.createElement('div');" +
+          "          expand.className = 'resize-sensor-expand';" +
+          "          setStyle(expand, style);" +
+          "          var expandChild = document.createElement('div');" +
+          "          setStyle(expandChild, styleChild);" +
+          "          expand.appendChild(expandChild);" +
+          "          var shrink = document.createElement('div');" +
+          "          shrink.className = 'resize-sensor-shrink';" +
+          "          setStyle(shrink, style);" +
+          "          var shrinkChild = document.createElement('div');" +
+          "          setStyle(shrinkChild, styleChild);" +
+          "          setStyle(shrinkChild, { width: '200%', height: '200%' });" +
+          "          shrink.appendChild(shrinkChild);" +
+          "          element.resizeSensor.appendChild(expand);" +
+          "          element.resizeSensor.appendChild(shrink);" +
+          "          element.appendChild(element.resizeSensor);" +
+          "          var computedStyle = window.getComputedStyle(element);" +
+          "          var position = computedStyle" +
+          "            ? computedStyle.getPropertyValue('position')" +
+          "            : null;" +
+          "          if (" +
+          "            'absolute' !== position &&" +
+          "            'relative' !== position &&" +
+          "            'fixed' !== position &&" +
+          "            'sticky' !== position" +
+          "          ) {" +
+          "            element.style.position = 'relative';" +
+          "          }" +
+          "          var dirty, rafId;" +
+          "          var size = getElementSize(element);" +
+          "          var lastWidth = 0;" +
+          "          var lastHeight = 0;" +
+          "          var initialHiddenCheck = true;" +
+          "          lastAnimationFrame = 0;" +
+          "          var resetExpandShrink = function() {" +
+          "            var width = element.offsetWidth;" +
+          "            var height = element.offsetHeight;" +
+          "            expandChild.style.width = width + 10 + 'px';" +
+          "            expandChild.style.height = height + 10 + 'px';" +
+          "            expand.scrollLeft = width + 10;" +
+          "            expand.scrollTop = height + 10;" +
+          "            shrink.scrollLeft = width + 10;" +
+          "            shrink.scrollTop = height + 10;" +
+          "          };" +
+          "          var reset = function() {" +
+          "            if (initialHiddenCheck) {" +
+          "              var invisible =" +
+          "                element.offsetWidth === 0 && element.offsetHeight === 0;" +
+          "              if (invisible) {" +
+          "                if (!lastAnimationFrame) {" +
+          "                  lastAnimationFrame = requestAnimationFrame(function() {" +
+          "                    lastAnimationFrame = 0;" +
+          "                    reset();" +
+          "                  });" +
+          "                }" +
+          "                return;" +
+          "              } else {" +
+          "                initialHiddenCheck = false;" +
+          "              }" +
+          "            }" +
+          "            resetExpandShrink();" +
+          "          };" +
+          "          element.resizeSensor.resetSensor = reset;" +
+          "          var onResized = function() {" +
+          "            rafId = 0;" +
+          "            if (!dirty) return;" +
+          "            lastWidth = size.width;" +
+          "            lastHeight = size.height;" +
+          "            if (element.resizedAttached) {" +
+          "              element.resizedAttached.call(size);" +
+          "            }" +
+          "          };" +
+          "          var onScroll = function() {" +
+          "            size = getElementSize(element);" +
+          "            dirty = size.width !== lastWidth || size.height !== lastHeight;" +
+          "            if (dirty && !rafId) {" +
+          "              rafId = requestAnimationFrame(onResized);" +
+          "            }" +
+          "            reset();" +
+          "          };" +
+          "          var addEvent = function(el, name, cb) {" +
+          "            if (el.attachEvent) {" +
+          "              el.attachEvent('on' + name, cb);" +
+          "            } else {" +
+          "              el.addEventListener(name, cb);" +
+          "            }" +
+          "          };" +
+          "          addEvent(expand, 'scroll', onScroll);" +
+          "          addEvent(shrink, 'scroll', onScroll);" +
+          "          lastAnimationFrame = requestAnimationFrame(reset);" +
+          "        }" +
+          "        forEachElement(element, function(elem) {" +
+          "          attachResizeEvent(elem, callback);" +
+          "        });" +
+          "        this.detach = function(ev) {" +
+          "          if (!lastAnimationFrame) {" +
+          "            window.cancelAnimationFrame(lastAnimationFrame);" +
+          "            lastAnimationFrame = 0;" +
+          "          }" +
+          "          ResizeSensor.detach(element, ev);" +
+          "        };" +
+          "        this.reset = function() {" +
+          "          element.resizeSensor.resetSensor();" +
+          "        };" +
+          "      };" +
+          "      ResizeSensor.reset = function(element) {" +
+          "        forEachElement(element, function(elem) {" +
+          "          elem.resizeSensor.resetSensor();" +
+          "        });" +
+          "      };" +
+          "      ResizeSensor.detach = function(element, ev) {" +
+          "        forEachElement(element, function(elem) {" +
+          "          if (!elem) return;" +
+          "          if (elem.resizedAttached && typeof ev === 'function') {" +
+          "            elem.resizedAttached.remove(ev);" +
+          "            if (elem.resizedAttached.length()) return;" +
+          "          }" +
+          "          if (elem.resizeSensor) {" +
+          "            if (elem.contains(elem.resizeSensor)) {" +
+          "              elem.removeChild(elem.resizeSensor);" +
+          "            }" +
+          "            delete elem.resizeSensor;" +
+          "            delete elem.resizedAttached;" +
+          "          }" +
+          "        });" +
+          "      };" +
+          "      if (typeof MutationObserver !== 'undefined') {" +
+          "        var observer = new MutationObserver(function(mutations) {" +
+          "          for (var i in mutations) {" +
+          "            if (mutations.hasOwnProperty(i)) {" +
+          "              var items = mutations[i].addedNodes;" +
+          "              for (var j = 0; j < items.length; j++) {" +
+          "                if (items[j].resizeSensor) {" +
+          "                  ResizeSensor.reset(items[j]);" +
+          "                }" +
+          "              }" +
+          "            }" +
+          "          }" +
+          "        });" +
+          "        document.addEventListener('DOMContentLoaded', function(event) {" +
+          "          observer.observe(document.body, {" +
+          "            childList: true," +
+          "            subtree: true" +
+          "          });" +
+          "        });" +
+          "      }" +
+          "      return ResizeSensor;" +
+          "    }" +
+          "    var ResizeSensor = prepare();" +
+          "    function pseudoStyle(htmlElement, pseudoElement, styles) {" +
+          "      var _sheetId = 'pseudoStyles';" +
+          "      var _head = document.head || document.getElementsByTagName('head')[0];" +
+          "      var _sheet =" +
+          "        document.getElementById(_sheetId) || document.createElement('style');" +
+          "      _sheet.id = _sheetId;" +
+          "      var styleClass = htmlElement.className.split(' ').join('.');" +
+          "      if (styleClass.charAt(0) != '.') {" +
+          "        styleClass = '.' + styleClass;" +
+          "      }" +
+          "      _sheet.innerHTML += '\\n' + styleClass + ':' + pseudoElement + '{';" +
+          "      for (var key in styles) {" +
+          "        _sheet.innerHTML += key + ':' + styles[key] + ';\\n';" +
+          "      }" +
+          "      _sheet.innerHTML += '}';" +
+          "      _head.appendChild(_sheet);" +
+          "    }" +
+          "    function getIndexSelectValues(select) {" +
+          "      var result = [];" +
+          "      var options = select && select.options;" +
+          "      for (var i = 0, iLen = options.length; i < iLen; i++) {" +
+          "        var opt = options[i];" +
+          "        if (opt.selected) {" +
+          "          result.push(i);" +
+          "        }" +
+          "      }" +
+          "      return result;" +
+          "    }" +
+          "    function setMultipleValues(select, values) {" +
+          "      var options = select && select.options;" +
+          "      for (var i = 0, iLen = options.length; i < iLen; i++) {" +
+          "        var opt = options[i];" +
+          "        opt.selected = values.indexOf(opt.value) >= 0;" +
+          "      }" +
+          "    }" +
+          "    function addSpanWrapper(selectElement) {" +
+          "      var spanElement = document.createElement('span');" +
+          "      spanElement.flutterInAppWebViewSelect = selectElement;" +
+          "      new ResizeSensor(spanElement, function() {" +
+          "        var style =" +
+          "          selectElement.currentStyle || window.getComputedStyle(selectElement);" +
+          "        var xMargin =" +
+          "          parseFloat(style.marginLeft) + parseFloat(style.marginRight);" +
+          "        var yMargin =" +
+          "          parseFloat(style.marginTop) + parseFloat(style.marginBottom);" +
+          "        selectElement.style.width =" +
+          "          spanElement.getBoundingClientRect().width - xMargin + 'px';" +
+          "        selectElement.style.height =" +
+          "          spanElement.getBoundingClientRect().height - yMargin + 'px';" +
+          "      });" +
+          "      spanElement.className = 'flutterInAppWebViewSelect-' + uuid;" +
+          "      spanElement.style.padding = '0px';" +
+          "      spanElement.style.margin = '0px';" +
+          "      spanElement.style.border = '0px';" +
+          "      spanElement.style.display = 'inline-block';" +
+          "      spanElement.style.backgroundColor = 'transparent';" +
+          "      spanElement.style.position = 'relative';" +
+          "      pseudoStyle(spanElement, 'before', {" +
+          "        content: '\\' \\''," +
+          "        width: '100%'," +
+          "        height: '100%'," +
+          "        position: 'absolute'," +
+          "        top: '0'," +
+          "        left: '0'," +
+          "        'z-index': 99999999" +
+          "      });" +
+          "      selectElement.flutterInAppWebViewSpanWrapper = spanElement;" +
+          "      var clickEventListener = function(event) {" +
+          "        var self = this;" +
+          "        event.preventDefault();" +
+          "        var isDisabled = !!this.flutterInAppWebViewSelect.disabled;" +
+          "        if (isDisabled) {" +
           "          return;" +
           "        }" +
-          "" +
-          "        element.resizedAttached = new EventQueue();" +
-          "        element.resizedAttached.add(resized);" +
-          "" +
-          "        element.resizeSensor = document.createElement(\"div\");" +
-          "        element.resizeSensor.dir = \"ltr\";" +
-          "        element.resizeSensor.className = \"resize-sensor\";" +
-          "" +
-          "        var style = {" +
-          "          pointerEvents: \"none\"," +
-          "          position: \"absolute\"," +
-          "          left: \"0px\"," +
-          "          top: \"0px\"," +
-          "          right: \"0px\"," +
-          "          bottom: \"0px\"," +
-          "          overflow: \"hidden\"," +
-          "          zIndex: \"-1\"," +
-          "          visibility: \"hidden\"," +
-          "          maxWidth: \"100%\"" +
-          "        };" +
-          "        var styleChild = {" +
-          "          position: \"absolute\"," +
-          "          left: \"0px\"," +
-          "          top: \"0px\"," +
-          "          transition: \"0s\"" +
-          "        };" +
-          "" +
-          "        setStyle(element.resizeSensor, style);" +
-          "" +
-          "        var expand = document.createElement(\"div\");" +
-          "        expand.className = \"resize-sensor-expand\";" +
-          "        setStyle(expand, style);" +
-          "" +
-          "        var expandChild = document.createElement(\"div\");" +
-          "        setStyle(expandChild, styleChild);" +
-          "        expand.appendChild(expandChild);" +
-          "" +
-          "        var shrink = document.createElement(\"div\");" +
-          "        shrink.className = \"resize-sensor-shrink\";" +
-          "        setStyle(shrink, style);" +
-          "" +
-          "        var shrinkChild = document.createElement(\"div\");" +
-          "        setStyle(shrinkChild, styleChild);" +
-          "        setStyle(shrinkChild, { width: \"200%\", height: \"200%\" });" +
-          "        shrink.appendChild(shrinkChild);" +
-          "" +
-          "        element.resizeSensor.appendChild(expand);" +
-          "        element.resizeSensor.appendChild(shrink);" +
-          "        element.appendChild(element.resizeSensor);" +
-          "" +
-          "        var computedStyle = window.getComputedStyle(element);" +
-          "        var position = computedStyle" +
-          "          ? computedStyle.getPropertyValue(\"position\")" +
-          "          : null;" +
-          "        if (" +
-          "          \"absolute\" !== position &&" +
-          "          \"relative\" !== position &&" +
-          "          \"fixed\" !== position &&" +
-          "          \"sticky\" !== position" +
-          "        ) {" +
-          "          element.style.position = \"relative\";" +
+          "        this.flutterInAppWebViewSelect.focus();" +
+          "        var options = [];" +
+          "        var optionElements = this.flutterInAppWebViewSelect.querySelectorAll(" +
+          "          'option'" +
+          "        );" +
+          "        for (var i = 0; i < optionElements.length; i++) {" +
+          "          var optionElement = optionElements[i];" +
+          "          options.push({" +
+          "            key: optionElement.textContent," +
+          "            value: optionElement.value" +
+          "          });" +
           "        }" +
-          "" +
-          "        var dirty, rafId;" +
-          "        var size = getElementSize(element);" +
-          "        var lastWidth = 0;" +
-          "        var lastHeight = 0;" +
-          "        var initialHiddenCheck = true;" +
-          "        lastAnimationFrame = 0;" +
-          "" +
-          "        var resetExpandShrink = function() {" +
-          "          var width = element.offsetWidth;" +
-          "          var height = element.offsetHeight;" +
-          "" +
-          "          expandChild.style.width = width + 10 + \"px\";" +
-          "          expandChild.style.height = height + 10 + \"px\";" +
-          "" +
-          "          expand.scrollLeft = width + 10;" +
-          "          expand.scrollTop = height + 10;" +
-          "" +
-          "          shrink.scrollLeft = width + 10;" +
-          "          shrink.scrollTop = height + 10;" +
-          "        };" +
-          "" +
-          "        var reset = function() {" +
-          "          if (initialHiddenCheck) {" +
-          "            var invisible =" +
-          "              element.offsetWidth === 0 && element.offsetHeight === 0;" +
-          "            if (invisible) {" +
-          "              if (!lastAnimationFrame) {" +
-          "                lastAnimationFrame = requestAnimationFrame(function() {" +
-          "                  lastAnimationFrame = 0;" +
-          "" +
-          "                  reset();" +
-          "                });" +
+          "        var isMultiple = !!this.flutterInAppWebViewSelect.multiple;" +
+          "        window.flutter_inappwebview" +
+          "          .callHandler(" +
+          "            'flutterInAppWebViewDropDownWorkaround'," +
+          "            getIndexSelectValues(this.flutterInAppWebViewSelect)," +
+          "            isMultiple," +
+          "            options" +
+          "          )" +
+          "          .then(function(result) {" +
+          "            if (result != null && result.values != null) {" +
+          "              if (!isMultiple) {" +
+          "                if (result.values.length > 0) {" +
+          "                  self.flutterInAppWebViewSelect.value = result.values[0];" +
+          "                }" +
+          "              } else {" +
+          "                setMultipleValues(" +
+          "                  self.flutterInAppWebViewSelect," +
+          "                  result.values" +
+          "                );" +
           "              }" +
-          "" +
-          "              return;" +
-          "            } else {" +
-          "              initialHiddenCheck = false;" +
           "            }" +
-          "          }" +
-          "" +
-          "          resetExpandShrink();" +
-          "        };" +
-          "        element.resizeSensor.resetSensor = reset;" +
-          "" +
-          "        var onResized = function() {" +
-          "          rafId = 0;" +
-          "" +
-          "          if (!dirty) return;" +
-          "" +
-          "          lastWidth = size.width;" +
-          "          lastHeight = size.height;" +
-          "" +
-          "          if (element.resizedAttached) {" +
-          "            element.resizedAttached.call(size);" +
-          "          }" +
-          "        };" +
-          "" +
-          "        var onScroll = function() {" +
-          "          size = getElementSize(element);" +
-          "          dirty = size.width !== lastWidth || size.height !== lastHeight;" +
-          "" +
-          "          if (dirty && !rafId) {" +
-          "            rafId = requestAnimationFrame(onResized);" +
-          "          }" +
-          "" +
-          "          reset();" +
-          "        };" +
-          "" +
-          "        var addEvent = function(el, name, cb) {" +
-          "          if (el.attachEvent) {" +
-          "            el.attachEvent(\"on\" + name, cb);" +
-          "          } else {" +
-          "            el.addEventListener(name, cb);" +
-          "          }" +
-          "        };" +
-          "" +
-          "        addEvent(expand, \"scroll\", onScroll);" +
-          "        addEvent(shrink, \"scroll\", onScroll);" +
-          "" +
-          "        lastAnimationFrame = requestAnimationFrame(reset);" +
-          "      }" +
-          "" +
-          "      forEachElement(element, function(elem) {" +
-          "        attachResizeEvent(elem, callback);" +
-          "      });" +
-          "" +
-          "      this.detach = function(ev) {" +
-          "        if (!lastAnimationFrame) {" +
-          "          window.cancelAnimationFrame(lastAnimationFrame);" +
-          "          lastAnimationFrame = 0;" +
-          "        }" +
-          "        ResizeSensor.detach(element, ev);" +
+          "            var evt = document.createEvent('HTMLEvents');" +
+          "            evt.initEvent('change', false, true);" +
+          "            self.flutterInAppWebViewSelect.dispatchEvent(evt);" +
+          "            self.flutterInAppWebViewSelect.blur();" +
+          "          });" +
           "      };" +
-          "" +
-          "      this.reset = function() {" +
-          "        element.resizeSensor.resetSensor();" +
-          "      };" +
-          "    };" +
-          "" +
-          "    ResizeSensor.reset = function(element) {" +
-          "      forEachElement(element, function(elem) {" +
-          "        elem.resizeSensor.resetSensor();" +
+          "      spanElement.addEventListener('click', clickEventListener);" +
+          "      divWithEventListeners.push({" +
+          "        spanElement: spanElement," +
+          "        clickEvent: clickEventListener" +
           "      });" +
-          "    };" +
-          "" +
-          "    ResizeSensor.detach = function(element, ev) {" +
-          "      forEachElement(element, function(elem) {" +
-          "        if (!elem) return;" +
-          "        if (elem.resizedAttached && typeof ev === \"function\") {" +
-          "          elem.resizedAttached.remove(ev);" +
-          "          if (elem.resizedAttached.length()) return;" +
-          "        }" +
-          "        if (elem.resizeSensor) {" +
-          "          if (elem.contains(elem.resizeSensor)) {" +
-          "            elem.removeChild(elem.resizeSensor);" +
+          "      selectElement.parentNode.insertBefore(spanElement, selectElement);" +
+          "      spanElement.appendChild(selectElement);" +
+          "      uuid++;" +
+          "    }" +
+          "    function removeSpanWrapper(selectElement) {" +
+          "      if (selectElement.flutterInAppWebViewSpanWrapper) {" +
+          "        divWithEventListeners.splice(" +
+          "          divWithEventListeners.indexOf(" +
+          "            selectElement.flutterInAppWebViewSpanWrapper" +
+          "          )," +
+          "          1" +
+          "        );" +
+          "        document.body.removeChild(selectElement.flutterInAppWebViewSpanWrapper);" +
+          "      }" +
+          "    }" +
+          "    var selectElements = document.querySelectorAll('select');" +
+          "    var divWithEventListeners = [];" +
+          "    for (var selectElement of selectElements) {" +
+          "      addSpanWrapper(selectElement);" +
+          "    }" +
+          "    var mutationObserver = new MutationObserver(function(mutations) {" +
+          "      mutations.forEach(function(mutation) {" +
+          "        for (var nodeElement of mutation.addedNodes) {" +
+          "          if (nodeElement.tagName == 'SELECT') {" +
+          "            addSpanWrapper(nodeElement);" +
           "          }" +
-          "          delete elem.resizeSensor;" +
-          "          delete elem.resizedAttached;" +
           "        }" +
-          "      });" +
-          "    };" +
-          "" +
-          "    if (typeof MutationObserver !== \"undefined\") {" +
-          "      var observer = new MutationObserver(function(mutations) {" +
-          "        for (var i in mutations) {" +
-          "          if (mutations.hasOwnProperty(i)) {" +
-          "            var items = mutations[i].addedNodes;" +
-          "            for (var j = 0; j < items.length; j++) {" +
-          "              if (items[j].resizeSensor) {" +
-          "                ResizeSensor.reset(items[j]);" +
-          "              }" +
+          "        for (var nodeElement of mutation.removedNodes) {" +
+          "          if (nodeElement.tagName == 'SELECT') {" +
+          "            removeSpanWrapper(nodeElement);" +
+          "            if (nodeElement.mutationObserver) {" +
+          "              nodeElement.mutationObserver.disconnect();" +
           "            }" +
           "          }" +
           "        }" +
           "      });" +
-          "" +
-          "      document.addEventListener(\"DOMContentLoaded\", function(event) {" +
-          "        observer.observe(document.body, {" +
-          "          childList: true," +
-          "          subtree: true" +
-          "        });" +
-          "      });" +
-          "    }" +
-          "" +
-          "    return ResizeSensor;" +
-          "  }" +
-          "  var ResizeSensor = prepare();" +
-          "  function pseudoStyle(htmlElement, pseudoElement, styles) {" +
-          "    var _sheetId = \"pseudoStyles\";" +
-          "    var _head = document.head || document.getElementsByTagName(\"head\")[0];" +
-          "    var _sheet =" +
-          "      document.getElementById(_sheetId) || document.createElement(\"style\");" +
-          "    _sheet.id = _sheetId;" +
-          "    var styleClass = htmlElement.className.split(\" \").join(\".\");" +
-          "    if (styleClass.charAt(0) != \".\") {" +
-          "      styleClass = \".\" + styleClass;" +
-          "    }" +
-          "    _sheet.innerHTML += \"\n\" + styleClass + \":\" + pseudoElement + \"{\";" +
-          "    for (var key in styles) {" +
-          "      _sheet.innerHTML += key + \":\" + styles[key] + \";\n\";" +
-          "    }" +
-          "    _sheet.innerHTML += \"}\";" +
-          "    _head.appendChild(_sheet);" +
-          "  }" +
-          "  function getIndexSelectValues(select) {" +
-          "    var result = [];" +
-          "    var options = select && select.options;" +
-          "    for (var i = 0, iLen = options.length; i < iLen; i++) {" +
-          "      var opt = options[i];" +
-          "      if (opt.selected) {" +
-          "        result.push(i);" +
-          "      }" +
-          "    }" +
-          "    return result;" +
-          "  }" +
-          "  function setMultipleValues(select, values) {" +
-          "    var options = select && select.options;" +
-          "    for (var i = 0, iLen = options.length; i < iLen; i++) {" +
-          "      var opt = options[i];" +
-          "      opt.selected = values.indexOf(opt.value) >= 0;" +
-          "    }" +
-          "  }" +
-          "  function addSpanWrapper(selectElement) {" +
-          "    var spanElement = document.createElement(\"span\");" +
-          "    spanElement.flutterInAppWebViewSelect = selectElement;" +
-          "    new ResizeSensor(spanElement, function() {" +
-          "      var style = selectElement.currentStyle || window.getComputedStyle(selectElement);" +
-          "      var xMargin = parseFloat(style.marginLeft) + parseFloat(style.marginRight);" +
-          "      var yMargin = parseFloat(style.marginTop) + parseFloat(style.marginBottom);" +
-          "      selectElement.style.width = (spanElement.getBoundingClientRect().width - xMargin) + \"px\";" +
-          "      selectElement.style.height = (spanElement.getBoundingClientRect().height - yMargin) + \"px\";" +
           "    });" +
-          "    spanElement.className = \"flutterInAppWebViewSelect-\" + uuid;" +
-          "    spanElement.style.padding = \"0px\";" +
-          "    spanElement.style.margin = \"0px\";" +
-          "    spanElement.style.border = \"0px\";" +
-          "    spanElement.style.display = \"inline-block\";" +
-          "    spanElement.style.backgroundColor = \"transparent\";" +
-          "    spanElement.style.position = \"relative\";" +
-          "    pseudoStyle(spanElement, \"before\", {" +
-          "      content: \"' '\"," +
-          "      width: \"100%\"," +
-          "      height: \"100%\"," +
-          "      position: \"absolute\"," +
-          "      top: \"0\"," +
-          "      left: \"0\"," +
-          "      \"z-index\": 99999999" +
+          "    mutationObserver.observe(document.body, {" +
+          "      childList: true," +
+          "      subtree: true" +
           "    });" +
-          "    selectElement.flutterInAppWebViewSpanWrapper = spanElement;" +
-          "    var clickEventListener = function(event) {" +
-          "      var self = this;" +
-          "      event.preventDefault();" +
-          "      var isDisabled = !!this.flutterInAppWebViewSelect.disabled;" +
-          "      if (isDisabled) {" +
-          "        return;" +
-          "      }" +
-          "      this.flutterInAppWebViewSelect.focus();" +
-          "      var options = [];" +
-          "      var optionElements = this.flutterInAppWebViewSelect.querySelectorAll(" +
-          "        \"option\"" +
-          "      );" +
-          "      for (var i = 0; i < optionElements.length; i++) {" +
-          "        var optionElement = optionElements[i];" +
-          "        options.push({" +
-          "          key: optionElement.textContent," +
-          "          value: optionElement.value" +
-          "        });" +
-          "      }" +
-          "      var isMultiple = !!this.flutterInAppWebViewSelect.multiple;" +
-          "      window." + JavaScriptBridgeInterface.name + ".callHandler(" +
-          "          \"flutterInAppWebViewDropDownWorkaround\"," +
-          "          getIndexSelectValues(this.flutterInAppWebViewSelect)," +
-          "          isMultiple," +
-          "          options" +
-          "        )" +
-          "        .then(function(result) {" +
-          "          if (result != null && result.values != null) {" +
-          "            if (!isMultiple) {" +
-          "              if (result.values.length > 0) {" +
-          "                self.flutterInAppWebViewSelect.value = result.values[0];" +
-          "              }" +
-          "            } else {" +
-          "              setMultipleValues(self.flutterInAppWebViewSelect, result.values);" +
-          "            }" +
-          "          }" +
-          "          var evt = document.createEvent('HTMLEvents');" +
-          "          evt.initEvent('change', false, true);" +
-          "          self.flutterInAppWebViewSelect.dispatchEvent(evt);" +
-          "          self.flutterInAppWebViewSelect.blur();" +
-          "        });" +
-          "    };" +
-          "    spanElement.addEventListener('click', clickEventListener);" +
-          "    divWithEventListeners.push({" +
-          "      spanElement: spanElement," +
-          "      clickEvent: clickEventListener" +
-          "    });" +
-          "    selectElement.parentNode.insertBefore(spanElement, selectElement);" +
-          "    spanElement.appendChild(selectElement);" +
-          "    uuid++;" +
           "  }" +
-          "  function removeSpanWrapper(selectElement) {" +
-          "    if (selectElement.flutterInAppWebViewSpanWrapper) {" +
-          "      divWithEventListeners.splice(" +
-          "        divWithEventListeners.indexOf(" +
-          "          selectElement.flutterInAppWebViewSpanWrapper" +
-          "        )," +
-          "        1" +
-          "      );" +
-          "      document.body.removeChild(selectElement.flutterInAppWebViewSpanWrapper);" +
-          "    }" +
-          "  }" +
-          "  var selectElements = document.querySelectorAll('select');" +
-          "  var divWithEventListeners = [];" +
-          "  for (var selectElement of selectElements) {" +
-          "    addSpanWrapper(selectElement);" +
-          "  }" +
-          "  var mutationObserver = new MutationObserver(function(mutations) {" +
-          "    mutations.forEach(function(mutation) {" +
-          "      for (var nodeElement of mutation.addedNodes) {" +
-          "        if (nodeElement.tagName == 'SELECT') {" +
-          "          addSpanWrapper(nodeElement);" +
+          "  document.addEventListener('DOMContentLoaded', function() {" +
+          "    dropDownWorkaround(window, document);" +
+          "    var iframes = document.querySelectorAll('iframe');" +
+          "    for (var i = 0; i < iframes.length; i++) {" +
+          "      var iframe = iframes[i];" +
+          "      var frameDocument;" +
+          "      try {" +
+          "        frameDocument = iframe.contentDocument;" +
+          "        if (!frameDocument && iframe.contentWindow) {" +
+          "          frameDocument = iframe.contentWindow.document;" +
           "        }" +
-          "      }" +
-          "      for (var nodeElement of mutation.removedNodes) {" +
-          "        if (nodeElement.tagName == 'SELECT') {" +
-          "          removeSpanWrapper(nodeElement);" +
-          "          if (nodeElement.mutationObserver) {" +
-          "            nodeElement.mutationObserver.disconnect();" +
-          "          }" +
+          "        if (frameDocument != null) {" +
+          "          dropDownWorkaround(window, frameDocument);" +
           "        }" +
+          "      } catch (error) {" +
+          "        console.error(error);" +
           "      }" +
-          "    });" +
-          "  });" +
-          "  mutationObserver.observe(document.body, {" +
-          "    childList: true," +
-          "    subtree: true" +
+          "    }" +
           "  });" +
           "})();";
 
diff --git a/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebViewClient.java b/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebViewClient.java
index 84d4f583..ffe9a4ea 100644
--- a/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebViewClient.java
+++ b/android/src/main/java/com/pichillilorenzo/flutter_inappwebview/InAppWebView/InAppWebViewClient.java
@@ -180,6 +180,9 @@ public class InAppWebViewClient extends WebViewClient {
     if (webView.options.useOnLoadResource) {
       js += InAppWebView.resourceObserverJS.replaceAll("[\r\n]+", "");
     }
+    if (webView.options.dropDownWorkaroundEnabled && Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
+      js += InAppWebView.dropDownWorkaroundJS.replaceAll("[\r\n]+", "");
+    }
     js += InAppWebView.printJS.replaceAll("[\r\n]+", "");
 
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
@@ -226,10 +229,6 @@ public class InAppWebViewClient extends WebViewClient {
 
     String js = InAppWebView.platformReadyJS.replaceAll("[\r\n]+", "");
 
-    if (webView.options.dropDownWorkaroundEnabled) {
-      js += InAppWebView.dropDownWorkaroundJS.replaceAll("[\r\n]+", "");
-    }
-
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
       webView.evaluateJavascript(js, (ValueCallback<String>) null);
     } else {
diff --git a/lib/src/webview_options.dart b/lib/src/webview_options.dart
index 1109221e..5ff96069 100644
--- a/lib/src/webview_options.dart
+++ b/lib/src/webview_options.dart
@@ -410,6 +410,7 @@ class AndroidInAppWebViewOptions
 
   ///Enable a temporary workaround for html dropdowns (`<select>` tags). It requires **JavaScript enabled**.
   ///It attempts to block click events for the dropdowns creating a custom `<div>` layer over the dropdown to intercept user's clicks.
+  ///This workaround is applied as soon as the web page fires the `DOMContentLoaded` JavaScript event.
   ///The default value is `false`.
   ///
   ///**NOTE**: available on Android 19+.