Move both of activity and observer into a helper object.

0xZOne · 0xZOne · commit c52d2deb5f43 · 2021-10-28T10:17:41.000+08:00
diff --git a/packages/image_picker/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/ImagePickerPlugin.java b/packages/image_picker/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/ImagePickerPlugin.java
@@ -90,6 +90,24 @@ public void onActivityStopped(Activity activity) {
     }
   }
 
+  private class ActivityState {
+    private final Activity activity;
+    private final LifeCycleObserver observer;
+
+    ActivityState(final Activity activity) {
+      this.activity = activity;
+      observer = new LifeCycleObserver(activity);
+    }
+
+    final Activity getActivity() {
+      return activity;
+    }
+
+    final LifeCycleObserver getObserver() {
+      return observer;
+    }
+  }
+
   static final String METHOD_CALL_IMAGE = "pickImage";
   static final String METHOD_CALL_MULTI_IMAGE = "pickMultiImage";
   static final String METHOD_CALL_VIDEO = "pickVideo";
@@ -106,10 +124,9 @@ public void onActivityStopped(Activity activity) {
   private FlutterPluginBinding pluginBinding;
   private ActivityPluginBinding activityBinding;
   private Application application;
-  @VisibleForTesting /*package*/ Activity activity;
   // This is null when not using v2 embedding;
   private Lifecycle lifecycle;
-  @VisibleForTesting /*package*/ LifeCycleObserver observer;
+  private ActivityState activityState;
 
   @SuppressWarnings("deprecation")
   public static void registerWith(io.flutter.plugin.common.PluginRegistry.Registrar registrar) {
@@ -138,7 +155,7 @@ public ImagePickerPlugin() {}
   @VisibleForTesting
   ImagePickerPlugin(final ImagePickerDelegate delegate, final Activity activity) {
     this.delegate = delegate;
-    this.activity = activity;
+    activityState = new ActivityState(activity);
   }
 
   @Override
@@ -183,39 +200,37 @@ private void setup(
       final Activity activity,
       final PluginRegistry.Registrar registrar,
       final ActivityPluginBinding activityBinding) {
-    this.activity = activity;
     this.application = application;
-    this.delegate = constructDelegate(activity);
+    delegate = constructDelegate(activity);
+    activityState = new ActivityState(activity);
     channel = new MethodChannel(messenger, CHANNEL);
     channel.setMethodCallHandler(this);
-    observer = new LifeCycleObserver(activity);
     if (registrar != null) {
       // V1 embedding setup for activity listeners.
-      application.registerActivityLifecycleCallbacks(observer);
+      application.registerActivityLifecycleCallbacks(activityState.getObserver());
       registrar.addActivityResultListener(delegate);
       registrar.addRequestPermissionsResultListener(delegate);
     } else {
       // V2 embedding setup for activity listeners.
       activityBinding.addActivityResultListener(delegate);
       activityBinding.addRequestPermissionsResultListener(delegate);
       lifecycle = FlutterLifecycleAdapter.getActivityLifecycle(activityBinding);
-      lifecycle.addObserver(observer);
+      lifecycle.addObserver(activityState.getObserver());
     }
   }
 
   private void tearDown() {
     activityBinding.removeActivityResultListener(delegate);
     activityBinding.removeRequestPermissionsResultListener(delegate);
     activityBinding = null;
-    lifecycle.removeObserver(observer);
+    lifecycle.removeObserver(activityState.getObserver());
     lifecycle = null;
     delegate = null;
     channel.setMethodCallHandler(null);
     channel = null;
-    application.unregisterActivityLifecycleCallbacks(observer);
+    application.unregisterActivityLifecycleCallbacks(activityState.getObserver());
     application = null;
-    activity = null;
-    observer = null;
+    activityState = null;
   }
 
   @VisibleForTesting
@@ -228,6 +243,11 @@ final ImagePickerDelegate constructDelegate(final Activity setupActivity) {
     return new ImagePickerDelegate(setupActivity, externalFilesDirectory, imageResizer, cache);
   }
 
+  @VisibleForTesting
+  final ActivityState getActivityState() {
+    return activityState;
+  }
+
   // MethodChannel.Result wrapper that responds on the platform thread.
   private static class MethodResultWrapper implements MethodChannel.Result {
     private MethodChannel.Result methodResult;
@@ -275,7 +295,7 @@ public void run() {
 
   @Override
   public void onMethodCall(MethodCall call, MethodChannel.Result rawResult) {
-    if (activity == null) {
+    if (activityState.getActivity() == null) {
       rawResult.error("no_activity", "image_picker plugin requires a foreground activity.", null);
       return;
     }
diff --git a/packages/image_picker/image_picker/android/src/test/java/io/flutter/plugins/imagepicker/ImagePickerPluginTest.java b/packages/image_picker/image_picker/android/src/test/java/io/flutter/plugins/imagepicker/ImagePickerPluginTest.java
@@ -82,12 +82,10 @@ public void onDetachedFromActivity_ShouldReleaseActivity() {
 
     plugin.onAttachedToEngine(mockPluginBinding);
     plugin.onAttachedToActivity(mockActivityBinding);
-    assertNotNull(plugin.activity);
-    assertNotNull(plugin.observer);
+    assertNotNull(plugin.getActivityState());
 
     plugin.onDetachedFromActivity();
-    assertNull(plugin.activity);
-    assertNull(plugin.observer);
+    assertNull(plugin.getActivityState());
   }
 
   @Test
