Databinding model (airbnb#188)

epoxy-adapter/src/main/java/com/airbnb/epoxy/DiffPayload.java

@@ -16,7 +16,7 @@ public class DiffPayload {
   private final EpoxyModel<?> singleModel;
   private final LongSparseArray<EpoxyModel<?>> modelsById;
 
-  DiffPayload(List<EpoxyModel<?>> models) {
+  DiffPayload(List<? extends EpoxyModel<?>> models) {
     if (models.isEmpty()) {
       throw new IllegalStateException("Models must not be empty");
     }

epoxy-databinding/.gitignore

@@ -0,0 +1 @@
+/build

epoxy-databinding/build.gradle

@@ -0,0 +1,36 @@
+apply plugin: 'com.android.library'
+
+android {
+  compileSdkVersion rootProject.COMPILE_SDK_VERSION
+  buildToolsVersion rootProject.ANDROID_BUILD_TOOLS_VERSION
+
+  defaultConfig {
+    minSdkVersion rootProject.MIN_SDK_VERSION
+    targetSdkVersion rootProject.TARGET_SDK_VERSION
+  }
+
+  dataBinding {
+    enabled = true
+  }
+}
+
+configurations.all { strategy ->
+  strategy.resolutionStrategy.force rootProject.deps.androidAnnotations, rootProject.deps.androidRecyclerView,
+      rootProject.deps.androidDesignLibrary, rootProject.deps.androidSupportLibrary, rootProject.deps.junit,
+      rootProject.deps.robolectric, rootProject.deps.mockito
+}
+
+dependencies {
+  compile rootProject.deps.androidAnnotations
+  compile rootProject.deps.androidRecyclerView
+  compile rootProject.deps.androidDesignLibrary
+  compile rootProject.deps.androidSupportLibrary
+  compile project(':epoxy-annotations')
+  compile project(':epoxy-adapter')
+
+  testCompile rootProject.deps.junit
+  testCompile rootProject.deps.robolectric
+  testCompile rootProject.deps.mockito
+}
+
+apply from: rootProject.file('gradle/gradle-maven-push.gradle')

epoxy-databinding/gradle.properties

@@ -0,0 +1,3 @@
+POM_NAME=Epoxy Data Binding Support
+POM_ARTIFACT_ID=epoxy-databinding
+POM_PACKAGING=jar

epoxy-databinding/proguard-rules.pro

@@ -0,0 +1,25 @@
+# Add project specific ProGuard rules here.
+# By default, the flags in this file are appended to flags specified
+# in /Users/eli_hart/tools/sdk/tools/proguard/proguard-android.txt
+# You can edit the include path and order by changing the proguardFiles
+# directive in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# Add any project specific keep options here:
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

epoxy-databinding/src/main/AndroidManifest.xml

@@ -0,0 +1,10 @@
+<manifest package="com.airbnb.epoxy.databinding"
+
+    xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <application android:allowBackup="true" android:label="@string/app_name"
+        android:supportsRtl="true">
+
+    </application>
+
+</manifest>

epoxy-databinding/src/main/java/com/airbnb/epoxy/DataBindingEpoxyModel.java

@@ -0,0 +1,112 @@
+package com.airbnb.epoxy;
+
+import android.databinding.DataBindingUtil;
+import android.databinding.ViewDataBinding;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+
+import com.airbnb.epoxy.DataBindingEpoxyModel.DataBindingHolder;
+
+import java.util.List;
+
+/**
+ * A version of {@link com.airbnb.epoxy.EpoxyModel} that can be used with databinding. The layout
+ * resource used with this model must be a databinding layout. This class will create the
+ * databinding object from the layout and call the {@link #setDataBindingVariables} methods when the
+ * view needs binding to the model.
+ * <p>
+ * The easiest way to use this model is to have Epoxy generate a model to do all the binding work
+ * for you. To do this, create an abstract subclass of this model, annotate it with {@link
+ * EpoxyModelClass}, and pass your layout resource as the layout param. (You must pass the layout
+ * this way instead of implementing {@link #getDefaultLayout()}).
+ * <p>
+ * Then, make a field to represent each of the data variables in your layout and annotate each one
+ * with {@link EpoxyAttribute}. The name of each field must match the name of the variable in the
+ * layout exactly.
+ * <p>
+ * Epoxy will generate a subclass of your model at compile time that implements {@link
+ * #setDataBindingVariables(ViewDataBinding)} and {@link #setDataBindingVariables(ViewDataBinding,
+ * EpoxyModel)} for you. This will do all binding for you, and also only bind variables that change
+ * if you update your model (Note: The change optimization only works when used with {@link
+ * EpoxyController}).
+ */
+public abstract class DataBindingEpoxyModel extends EpoxyModelWithHolder<DataBindingHolder> {
+
+  @Override
+  View buildView(ViewGroup parent) {
+    LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
+    ViewDataBinding binding = DataBindingUtil.inflate(layoutInflater, getViewType(), parent, false);
+    View view = binding.getRoot();
+    view.setTag(binding);
+    return view;
+  }
+
+  @Override
+  public void bind(DataBindingHolder holder) {
+    setDataBindingVariables(holder.dataBinding);
+    holder.dataBinding.executePendingBindings();
+  }
+
+  @Override
+  public void bind(DataBindingHolder holder, EpoxyModel<?> previouslyBoundModel) {
+    setDataBindingVariables(holder.dataBinding, previouslyBoundModel);
+    holder.dataBinding.executePendingBindings();
+  }
+
+  @Override
+  public void bind(DataBindingHolder holder, List<Object> payloads) {
+    setDataBindingVariables(holder.dataBinding, payloads);
+    holder.dataBinding.executePendingBindings();
+  }
+
+  /**
+   * This is called when the model is bound to a view, and the view's variables should be updated
+   * with the model's data. {@link ViewDataBinding#executePendingBindings()} is called for you after
+   * this method is run.
+   * <p>
+   * If you leave your class abstract and have a model generated for you via annotations this will
+   * be implemented for you. However, you may choose to implement this manually if you like.
+   */
+  protected abstract void setDataBindingVariables(ViewDataBinding binding);
+
+  /**
+   * Similar to {@link #setDataBindingVariables(ViewDataBinding)}, but this method only binds
+   * variables that have changed. The changed model comes from {@link #bind(DataBindingHolder,
+   * EpoxyModel)}. This will only be called if the model is used in an {@link EpoxyController}
+   * <p>
+   * If you leave your class abstract and have a model generated for you via annotations this will
+   * be implemented for you. However, you may choose to implement this manually if you like.
+   */
+  protected void setDataBindingVariables(ViewDataBinding dataBinding,
+      EpoxyModel<?> previouslyBoundModel) {
+    setDataBindingVariables(dataBinding);
+  }
+
+  protected void setDataBindingVariables(ViewDataBinding dataBinding, List<Object> payloads) {
+    setDataBindingVariables(dataBinding);
+  }
+
+  @Override
+  public void unbind(DataBindingHolder holder) {
+    holder.dataBinding.unbind();
+  }
+
+  @Override
+  protected final DataBindingHolder createNewHolder() {
+    return new DataBindingHolder();
+  }
+
+  public static class DataBindingHolder extends EpoxyHolder {
+    private ViewDataBinding dataBinding;
+
+    public ViewDataBinding getDataBinding() {
+      return dataBinding;
+    }
+
+    @Override
+    protected void bindView(View itemView) {
+      dataBinding = (ViewDataBinding) itemView.getTag();
+    }
+  }
+}

epoxy-databinding/src/main/res/values/strings.xml

@@ -0,0 +1,3 @@
+<resources>
+    <string name="app_name">Epoxy DataBinding</string>
+</resources>

epoxy-integrationtest/build.gradle

@@ -1,18 +1,28 @@
-apply plugin: 'com.android.library'
+apply plugin: 'com.android.application'
 
 android {
+
   compileSdkVersion rootProject.COMPILE_SDK_VERSION
   buildToolsVersion rootProject.ANDROID_BUILD_TOOLS_VERSION
 
   defaultConfig {
+    applicationId "com.airbnb.android.epoxy"
     minSdkVersion rootProject.MIN_SDK_VERSION
     targetSdkVersion rootProject.TARGET_SDK_VERSION
+    vectorDrawables.useSupportLibrary = true
+    versionCode 1
+    versionName "1.0"
+  }
+
+  dataBinding {
+    enabled = true
   }
 }
 
 dependencies {
   compile project(':epoxy-adapter')
   compile project(':epoxy-annotations')
+  compile project(':epoxy-databinding')
   annotationProcessor project(':epoxy-processor')
 
   testCompile rootProject.deps.junit

epoxy-integrationtest/src/main/AndroidManifest.xml

@@ -1,7 +1,11 @@
-<manifest package="com.airbnb.epoxy" xmlns:android="http://schemas.android.com/apk/res/android">
+<?xml version="1.0" encoding="utf-8"?>
+<manifest package="com.airbnb.epoxy"
+    xmlns:android="http://schemas.android.com/apk/res/android">
 
-    <application android:allowBackup="true" android:label="@string/app_name"
-        android:supportsRtl="true">
+    <application
+        android:allowBackup="true"
+        android:label="@string/app_name"
+        android:theme="@style/Theme.AppCompat.Light">
 
     </application>
 

epoxy-integrationtest/src/main/java/com/airbnb/epoxy/AdapterWithFieldAssigned.java

@@ -0,0 +1,11 @@
+package com.airbnb.epoxy;
+
+class AdapterWithFieldAssigned extends EpoxyController {
+
+  @AutoModel Model_ model1 = new Model_();
+
+  @Override
+  protected void buildModels() {
+    add(model1);
+  }
+}

epoxy-integrationtest/src/main/java/com/airbnb/epoxy/AdapterWithIdChanged.java

@@ -0,0 +1,11 @@
+package com.airbnb.epoxy;
+
+class AdapterWithIdChanged extends EpoxyController {
+
+  @AutoModel Model_ model1 = new Model_();
+
+  @Override
+  protected void buildModels() {
+    add(model1.id(23));
+  }
+}

epoxy-integrationtest/src/main/java/com/airbnb/epoxy/BasicAutoModelsAdapter.java

@@ -0,0 +1,13 @@
+package com.airbnb.epoxy;
+
+class BasicAutoModelsAdapter extends EpoxyController {
+
+  @AutoModel Model_ model1;
+  @AutoModel Model_ model2;
+
+  @Override
+  protected void buildModels() {
+    add(model1.id(1));
+    add(model2.id(2));
+  }
+}

epoxy-integrationtest/src/main/java/com/airbnb/epoxy/ModelChangesDuringBind.java

@@ -0,0 +1,18 @@
+package com.airbnb.epoxy;
+
+import android.view.View;
+
+class ModelChangesDuringBind extends EpoxyModel<View> {
+  @EpoxyAttribute int value;
+
+  @Override
+  protected int getDefaultLayout() {
+    return R.layout.model_with_click_listener;
+  }
+
+  @Override
+  public void bind(View view) {
+    super.bind(view);
+    value = 3;
+  }
+}

epoxy-integrationtest/src/main/java/com/airbnb/epoxy/TestDataBindingModel.java

@@ -0,0 +1,6 @@
+package com.airbnb.epoxy;
+
+@EpoxyModelClass(layout = R.layout.model_with_data_binding)
+abstract class TestDataBindingModel extends DataBindingEpoxyModel {
+  @EpoxyAttribute String stringValue;
+}

epoxy-integrationtest/src/main/res/layout/model_with_data_binding.xml

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <data>
+
+        <variable
+            name="stringValue"
+            type="String" />
+    </data>
+
+    <Button
+        android:id="@+id/button"
+        android:layout_width="match_parent"
+        android:layout_height="40dp"
+        android:text="@{stringValue}" />
+
+</layout>