[webview_flutter_android] Fix Android lint warnings

packages/webview_flutter/webview_flutter_android/CHANGELOG.md

@@ -1,7 +1,9 @@
-## NEXT
+## 3.4.6
 
 * Bumps androidx.webkit:webkit from 1.6.0 to 1.6.1.
 * Fixes common typos in tests and documentation.
+* Updates pigeon dev dependency to `9.2.4`.
+* Fixes Android lint warnings.
 
 ## 3.4.5
 

packages/webview_flutter/webview_flutter_android/android/build.gradle

@@ -33,7 +33,6 @@ android {
         checkAllWarnings true
         warningsAsErrors true
         disable 'AndroidGradlePluginVersion', 'InvalidPackage', 'GradleDependency'
-        baseline file("lint-baseline.xml")
     }
 
     dependencies {

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

@@ -6,10 +6,12 @@
 
 import android.os.Build;
 import android.webkit.CookieManager;
+import androidx.annotation.NonNull;
+import io.flutter.plugins.webviewflutter.GeneratedAndroidWebView.CookieManagerHostApi;
 
-class CookieManagerHostApiImpl implements GeneratedAndroidWebView.CookieManagerHostApi {
+class CookieManagerHostApiImpl implements CookieManagerHostApi {
   @Override
-  public void clearCookies(GeneratedAndroidWebView.Result<Boolean> result) {
+  public void clearCookies(@NonNull GeneratedAndroidWebView.Result<Boolean> result) {
     CookieManager cookieManager = CookieManager.getInstance();
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
       cookieManager.removeAllCookies(result::success);
@@ -19,7 +21,7 @@ public void clearCookies(GeneratedAndroidWebView.Result<Boolean> result) {
   }
 
   @Override
-  public void setCookie(String url, String value) {
+  public void setCookie(@NonNull String url, @NonNull String value) {
     CookieManager.getInstance().setCookie(url, value);
   }
 

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

@@ -6,7 +6,6 @@
 
 import static android.hardware.display.DisplayManager.DisplayListener;
 
-import android.annotation.TargetApi;
 import android.hardware.display.DisplayManager;
 import android.os.Build;
 import android.util.Log;
@@ -39,7 +38,6 @@
  * first initialization of a webview within the process the difference between the lists is the
  * webview's display listener.
  */
-@TargetApi(Build.VERSION_CODES.KITKAT)
 class DisplayListenerProxy {
   private static final String TAG = "DisplayListenerProxy";
 

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

@@ -5,6 +5,7 @@
 package io.flutter.plugins.webviewflutter;
 
 import android.webkit.DownloadListener;
+import androidx.annotation.NonNull;
 import io.flutter.plugin.common.BinaryMessenger;
 import io.flutter.plugins.webviewflutter.GeneratedAndroidWebView.DownloadListenerFlutterApi;
 
@@ -23,20 +24,20 @@ public class DownloadListenerFlutterApiImpl extends DownloadListenerFlutterApi {
    * @param instanceManager maintains instances stored to communicate with Dart objects
    */
   public DownloadListenerFlutterApiImpl(
-      BinaryMessenger binaryMessenger, InstanceManager instanceManager) {
+      @NonNull BinaryMessenger binaryMessenger, @NonNull InstanceManager instanceManager) {
     super(binaryMessenger);
     this.instanceManager = instanceManager;
   }
 
   /** Passes arguments from {@link DownloadListener#onDownloadStart} to Dart. */
   public void onDownloadStart(
-      DownloadListener downloadListener,
-      String url,
-      String userAgent,
-      String contentDisposition,
-      String mimetype,
+      @NonNull DownloadListener downloadListener,
+      @NonNull String url,
+      @NonNull String userAgent,
+      @NonNull String contentDisposition,
+      @NonNull String mimetype,
       long contentLength,
-      Reply<Void> callback) {
+      @NonNull Reply<Void> callback) {
     onDownloadStart(
         getIdentifierForListener(downloadListener),
         url,

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

@@ -35,10 +35,10 @@ public DownloadListenerImpl(@NonNull DownloadListenerFlutterApiImpl flutterApi)
 
     @Override
     public void onDownloadStart(
-        String url,
-        String userAgent,
-        String contentDisposition,
-        String mimetype,
+        @NonNull String url,
+        @NonNull String userAgent,
+        @NonNull String contentDisposition,
+        @NonNull String mimetype,
         long contentLength) {
       flutterApi.onDownloadStart(
           this, url, userAgent, contentDisposition, mimetype, contentLength, reply -> {});
@@ -53,7 +53,9 @@ public static class DownloadListenerCreator {
      * @param flutterApi handles sending messages to Dart
      * @return the created {@link DownloadListenerImpl}
      */
-    public DownloadListenerImpl createDownloadListener(DownloadListenerFlutterApiImpl flutterApi) {
+    @NonNull
+    public DownloadListenerImpl createDownloadListener(
+        @NonNull DownloadListenerFlutterApiImpl flutterApi) {
       return new DownloadListenerImpl(flutterApi);
     }
   }
@@ -66,16 +68,16 @@ public DownloadListenerImpl createDownloadListener(DownloadListenerFlutterApiImp
    * @param flutterApi handles sending messages to Dart
    */
   public DownloadListenerHostApiImpl(
-      InstanceManager instanceManager,
-      DownloadListenerCreator downloadListenerCreator,
-      DownloadListenerFlutterApiImpl flutterApi) {
+      @NonNull InstanceManager instanceManager,
+      @NonNull DownloadListenerCreator downloadListenerCreator,
+      @NonNull DownloadListenerFlutterApiImpl flutterApi) {
     this.instanceManager = instanceManager;
     this.downloadListenerCreator = downloadListenerCreator;
     this.flutterApi = flutterApi;
   }
 
   @Override
-  public void create(Long instanceId) {
+  public void create(@NonNull Long instanceId) {
     final DownloadListener downloadListener =
         downloadListenerCreator.createDownloadListener(flutterApi);
     instanceManager.addDartCreatedInstance(downloadListener, instanceId);

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

@@ -6,6 +6,7 @@
 
 import android.os.Build;
 import android.webkit.WebChromeClient;
+import androidx.annotation.NonNull;
 import androidx.annotation.RequiresApi;
 import io.flutter.plugin.common.BinaryMessenger;
 import java.util.Arrays;
@@ -28,7 +29,7 @@ public class FileChooserParamsFlutterApiImpl
    * @param instanceManager maintains instances stored to communicate with Dart objects
    */
   public FileChooserParamsFlutterApiImpl(
-      BinaryMessenger binaryMessenger, InstanceManager instanceManager) {
+      @NonNull BinaryMessenger binaryMessenger, @NonNull InstanceManager instanceManager) {
     super(binaryMessenger);
     this.instanceManager = instanceManager;
   }
@@ -58,7 +59,8 @@ private static GeneratedAndroidWebView.FileChooserModeEnumData toFileChooserEnum
    * Stores the FileChooserParams instance and notifies Dart to create a new FileChooserParams
    * instance that is attached to this one.
    */
-  public void create(WebChromeClient.FileChooserParams instance, Reply<Void> callback) {
+  public void create(
+      @NonNull WebChromeClient.FileChooserParams instance, @NonNull Reply<Void> callback) {
     if (!instanceManager.containsInstance(instance)) {
       create(
           instanceManager.addHostCreatedInstance(instance),

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

@@ -11,6 +11,7 @@
 import java.io.IOException;
 
 /** Provides access to the assets registered as part of the App bundle. */
+@SuppressWarnings({"deprecation", "DeprecatedIsStillUsed"})
 abstract class FlutterAssetManager {
   final AssetManager assetManager;
 

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

@@ -5,6 +5,7 @@
 package io.flutter.plugins.webviewflutter;
 
 import android.webkit.WebView;
+import androidx.annotation.NonNull;
 import io.flutter.plugins.webviewflutter.GeneratedAndroidWebView.FlutterAssetManagerHostApi;
 import java.io.IOException;
 import java.util.ArrayList;
@@ -20,12 +21,13 @@ public class FlutterAssetManagerHostApiImpl implements FlutterAssetManagerHostAp
   final FlutterAssetManager flutterAssetManager;
 
   /** Constructs a new instance of {@link FlutterAssetManagerHostApiImpl}. */
-  public FlutterAssetManagerHostApiImpl(FlutterAssetManager flutterAssetManager) {
+  public FlutterAssetManagerHostApiImpl(@NonNull FlutterAssetManager flutterAssetManager) {
     this.flutterAssetManager = flutterAssetManager;
   }
 
+  @NonNull
   @Override
-  public List<String> list(String path) {
+  public List<String> list(@NonNull String path) {
     try {
       String[] paths = flutterAssetManager.list(path);
 
@@ -39,8 +41,9 @@ public List<String> list(String path) {
     }
   }
 
+  @NonNull
   @Override
-  public String getAssetFilePathByName(String name) {
+  public String getAssetFilePathByName(@NonNull String name) {
     return flutterAssetManager.getAssetFilePathByName(name);
   }
 }

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

@@ -5,6 +5,8 @@
 package io.flutter.plugins.webviewflutter;
 
 import android.content.Context;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import io.flutter.plugin.common.StandardMessageCodec;
 import io.flutter.plugin.platform.PlatformView;
 import io.flutter.plugin.platform.PlatformViewFactory;
@@ -17,9 +19,15 @@ class FlutterWebViewFactory extends PlatformViewFactory {
     this.instanceManager = instanceManager;
   }
 
+  @NonNull
   @Override
-  public PlatformView create(Context context, int id, Object args) {
-    final PlatformView view = (PlatformView) instanceManager.getInstance((Integer) args);
+  public PlatformView create(Context context, int viewId, @Nullable Object args) {
+    final Integer identifier = (Integer) args;
+    if (identifier == null) {
+      throw new IllegalStateException("An identifier is required to retrieve WebView instance.");
+    }
+
+    final PlatformView view = instanceManager.getInstance(identifier);
     if (view == null) {
       throw new IllegalStateException("Unable to find WebView instance: " + args);
     }