Perform Hilt Activity injection on a OnContextAvailableListener.

Delay Hilt activity injection to a OnContextAvailableListener to enable member injecting ViewModels with SavedStateHandle. Note that this means base Hilt classes should not rely on their fields being injected before their onCreate() since injection is moved into super.onCreate() as opposed to before. RELNOTES=Delay Hilt activity injection to a OnContextAvailableListener to enable member injecting ViewModels with SavedStateHandle. To use the ContextAware APIs androidx.activity, androidx.fragment and androidx.lifecycle dependencies are updated across the Dagger libraries. PiperOrigin-RevId: 357829271
google · Feb 17, 2021 · 623d3a6 · 623d3a6
1 parent 6778a01
commit 623d3a6
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Showing 3 changed files with 34 additions and 23 deletions.
diff --git a/WORKSPACE b/WORKSPACE
@@ -104,10 +104,10 @@ maven_install(
     artifacts = [
         "androidx.annotation:annotation:1.1.0",
         "androidx.appcompat:appcompat:1.2.0",
-        "androidx.activity:activity:1.1.0",
-        "androidx.fragment:fragment:1.2.5",
-        "androidx.lifecycle:lifecycle-viewmodel:2.2.0",
-        "androidx.lifecycle:lifecycle-viewmodel-savedstate:2.2.0",
+        "androidx.activity:activity:1.2.0",
+        "androidx.fragment:fragment:1.3.0",
+        "androidx.lifecycle:lifecycle-viewmodel:2.3.0",
+        "androidx.lifecycle:lifecycle-viewmodel-savedstate:2.3.0",
         "androidx.multidex:multidex:2.0.1",
         "androidx.savedstate:savedstate:1.0.0",
         "androidx.test:monitor:1.1.1",

diff --git a/java/dagger/hilt/android/processor/internal/AndroidClassNames.java b/java/dagger/hilt/android/processor/internal/AndroidClassNames.java
@@ -113,5 +113,10 @@ public final class AndroidClassNames {
   public static final ClassName SAVED_STATE_HANDLE =
       get("androidx.lifecycle", "SavedStateHandle");
 
+  public static final ClassName ON_CONTEXT_AVAILABLE_LISTENER =
+      get("androidx.activity.contextaware", "OnContextAvailableListener");
+  public static final ClassName INJECT_VIA_ON_CONTEXT_AVAILABLE_LISTENER =
+      get("dagger.hilt.android", "InjectViaOnContextAvailableListener");
+
   private AndroidClassNames() {}
 }
diff --git a/java/dagger/hilt/android/processor/internal/androidentrypoint/ActivityGenerator.java b/java/dagger/hilt/android/processor/internal/androidentrypoint/ActivityGenerator.java
@@ -17,9 +17,9 @@
 package dagger.hilt.android.processor.internal.androidentrypoint;
 
 import com.squareup.javapoet.ClassName;
+import com.squareup.javapoet.CodeBlock;
 import com.squareup.javapoet.JavaFile;
 import com.squareup.javapoet.MethodSpec;
-import com.squareup.javapoet.ParameterSpec;
 import com.squareup.javapoet.TypeSpec;
 import com.squareup.javapoet.TypeVariableName;
 import dagger.hilt.android.processor.internal.AndroidClassNames;
@@ -56,9 +56,9 @@ public void generate() throws IOException {
     Generators.addGeneratedBaseClassJavadoc(builder, AndroidClassNames.ANDROID_ENTRY_POINT);
     Processors.addGeneratedAnnotation(builder, env, getClass());
 
-      Generators.copyConstructors(metadata.baseElement(), builder);
-      builder.addMethod(onCreate());
-
+      Generators.copyConstructors(
+          metadata.baseElement(), CodeBlock.builder().addStatement("init()").build(), builder);
+      builder.addMethod(init());
 
     metadata.baseElement().getTypeParameters().stream()
         .map(TypeVariableName::get)
@@ -79,23 +79,29 @@ public void generate() throws IOException {
         .writeTo(env.getFiler());
   }
 
-  // @CallSuper
-  // @Override
-  // protected void onCreate(@Nullable Bundle savedInstanceState) {
-  //   inject();
-  //   super.onCreate(savedInstanceState);
+  // private void init() {
+  //   addOnContextAvailableListener(new OnContextAvailableListener() {
+  //     @Override
+  //     public void onContextAvailable(Context context) {
+  //       inject();
+  //     }
+  //   });
   // }
-  private MethodSpec onCreate() {
-    return MethodSpec.methodBuilder("onCreate")
-        .addAnnotation(AndroidClassNames.CALL_SUPER)
-        .addAnnotation(Override.class)
-        .addModifiers(Modifier.PROTECTED)
-        .addParameter(
-            ParameterSpec.builder(AndroidClassNames.BUNDLE, "savedInstanceState")
-                .addAnnotation(AndroidClassNames.NULLABLE)
+  private MethodSpec init() {
+    return MethodSpec.methodBuilder("init")
+        .addModifiers(Modifier.PRIVATE)
+        .addStatement(
+            "addOnContextAvailableListener($L)",
+            TypeSpec.anonymousClassBuilder("")
+                .addSuperinterface(AndroidClassNames.ON_CONTEXT_AVAILABLE_LISTENER)
+                .addMethod(
+                    MethodSpec.methodBuilder("onContextAvailable")
+                        .addAnnotation(Override.class)
+                        .addModifiers(Modifier.PUBLIC)
+                        .addParameter(AndroidClassNames.CONTEXT, "context")
+                        .addStatement("inject()")
+                        .build())
                 .build())
-        .addStatement("inject()")
-        .addStatement("super.onCreate(savedInstanceState)")
         .build();
   }