diff --git a/android/build.gradle b/android/build.gradle
index ee6a0047..3fe16b1c 100644
--- a/android/build.gradle
+++ b/android/build.gradle
@@ -29,10 +29,21 @@ android {
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
 
         vectorDrawables.useSupportLibrary = true
+        consumerProguardFiles 'proguard-rules.pro'
     }
     lintOptions {
         disable 'InvalidPackage'
     }
+    buildTypes {
+        debug {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+        release {
+            minifyEnabled true
+            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
+        }
+    }
     dependencies {
         implementation 'androidx.webkit:webkit:1.0.0'
         implementation 'androidx.browser:browser:1.0.0'
diff --git a/android/proguard-rules.pro b/android/proguard-rules.pro
new file mode 100644
index 00000000..4930aa46
--- /dev/null
+++ b/android/proguard-rules.pro
@@ -0,0 +1,17 @@
+# WebView
+-keepattributes *JavascriptInterface*
+-keepclassmembers class * {
+    @android.webkit.JavascriptInterface <methods>;
+}
+-keepclassmembers class * extends android.webkit.WebViewClient {
+    public void *(android.webkit.WebView, java.lang.String, android.graphics.Bitmap);
+    public boolean *(android.webkit.WebView, java.lang.String);
+    public void *(android.webkit.webView, jav.lang.String);
+}
+-keepclassmembers class com.pichillilorenzo.flutter_inappbrowser$JavaScriptBridgeInterface {
+     <fields>;
+     <methods>;
+     public *;
+     private *;
+}
+-keep class com.pichillilorenzo.flutter_inappbrowser.** { *; }
\ No newline at end of file
diff --git a/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppBrowserFlutterPlugin.java b/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppBrowserFlutterPlugin.java
index a4247e05..f1faf117 100644
--- a/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppBrowserFlutterPlugin.java
+++ b/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppBrowserFlutterPlugin.java
@@ -1,6 +1,8 @@
 package com.pichillilorenzo.flutter_inappbrowser;
 
+import android.net.Uri;
 import android.os.Build;
+import android.webkit.ValueCallback;
 
 import io.flutter.plugin.common.MethodChannel;
 import io.flutter.plugin.common.PluginRegistry;
@@ -15,6 +17,8 @@ public class InAppBrowserFlutterPlugin implements FlutterPlugin {
   public static InAppBrowser inAppBrowser;
   public static MyCookieManager myCookieManager;
   public static CredentialDatabaseHandler credentialDatabaseHandler;
+  public static ValueCallback<Uri[]> uploadMessageArray;
+
 
   public InAppBrowserFlutterPlugin() {}
 
@@ -61,5 +65,6 @@ public class InAppBrowserFlutterPlugin implements FlutterPlugin {
       credentialDatabaseHandler.dispose();
       credentialDatabaseHandler = null;
     }
+    uploadMessageArray = null;
   }
 }
diff --git a/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppWebView/InAppWebViewChromeClient.java b/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppWebView/InAppWebViewChromeClient.java
index 750564e1..d181497c 100644
--- a/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppWebView/InAppWebViewChromeClient.java
+++ b/android/src/main/java/com/pichillilorenzo/flutter_inappbrowser/InAppWebView/InAppWebViewChromeClient.java
@@ -46,13 +46,11 @@ public class InAppWebViewChromeClient extends WebChromeClient implements PluginR
   private PluginRegistry.Registrar registrar;
   private FlutterWebView flutterWebView;
   private InAppBrowserActivity inAppBrowserActivity;
-  private ValueCallback<Uri[]> mUploadMessageArray;
   private ValueCallback<Uri> mUploadMessage;
   private final static int FILECHOOSER_RESULTCODE = 1;
 
   private View mCustomView;
   private WebChromeClient.CustomViewCallback mCustomViewCallback;
-  protected FrameLayout mFullscreenContainer;
   private int mOriginalOrientation;
   private int mOriginalSystemUiVisibility;
 
@@ -545,10 +543,8 @@ public class InAppWebViewChromeClient extends WebChromeClient implements PluginR
   }
 
   //For Android 5.0+
-  public boolean onShowFileChooser(
-          WebView webView, ValueCallback<Uri[]> filePathCallback,
-          FileChooserParams fileChooserParams) {
-    mUploadMessageArray = filePathCallback;
+  public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, FileChooserParams fileChooserParams) {
+    InAppBrowserFlutterPlugin.uploadMessageArray = filePathCallback;
     try {
       Intent contentSelectionIntent = new Intent(Intent.ACTION_GET_CONTENT);
       contentSelectionIntent.addCategory(Intent.CATEGORY_OPENABLE);
@@ -572,9 +568,9 @@ public class InAppWebViewChromeClient extends WebChromeClient implements PluginR
   @Override
   public boolean onActivityResult(int requestCode, int resultCode, Intent data) {
     if (requestCode == FILECHOOSER_RESULTCODE && (resultCode == RESULT_OK || resultCode == RESULT_CANCELED)) {
-      mUploadMessageArray.onReceiveValue(WebChromeClient.FileChooserParams.parseResult(resultCode, data));
+      InAppBrowserFlutterPlugin.uploadMessageArray.onReceiveValue(WebChromeClient.FileChooserParams.parseResult(resultCode, data));
     }
-    return false;
+    return true;
   }
 
   private MethodChannel getChannel() {