TBR: Prepping Firebase for persistence abstraction
Switching from singleton to instantiatable with static configuration. It
turns setAndroidContext is idempotent; setPersistenceEnabled was causing
the exception on rotation, and that should be cheap enough to do in a
static initializer.
Change-Id: I604718c7c54809594157527af9092fa8dd7ab23d
diff --git a/projects/todos/app/src/main/java/io/v/todos/MainActivity.java b/projects/todos/app/src/main/java/io/v/todos/MainActivity.java
index e2229b8..0157f18 100644
--- a/projects/todos/app/src/main/java/io/v/todos/MainActivity.java
+++ b/projects/todos/app/src/main/java/io/v/todos/MainActivity.java
@@ -24,7 +24,8 @@
import com.firebase.client.Firebase;
import com.firebase.client.FirebaseError;
-import io.v.todos.persistence.FirebasePersistence;
+import io.v.todos.persistence.Persistence;
+import io.v.todos.persistence.PersistenceFactory;
/**
* MainActivity for Vanadium TODOs
@@ -38,7 +39,8 @@
*/
public class MainActivity extends Activity {
static final String FIREBASE_EXAMPLE_URL = "https://vivid-heat-7354.firebaseio.com/";
- private Firebase myFirebaseRef;
+ private Persistence mPersistence;
+ private Firebase myFirebaseRef; // TODO(rosswang): migrate
// Snackoos are the code name for the list of todos.
// These todos are backed up at the SNACKOOS child of the Firebase URL.
@@ -57,6 +59,7 @@
@Override
protected void onDestroy() {
myFirebaseRef.removeEventListener(snackoosEventListener);
+ mPersistence.close();
super.onDestroy();
}
@@ -101,7 +104,7 @@
}).attachToRecyclerView(recyclerView);
// Prepare our Firebase Reference and the primary listener (SNACKOOS).
- FirebasePersistence.getDatabase(this);
+ mPersistence = PersistenceFactory.getPersistence(this);
myFirebaseRef = new Firebase(FIREBASE_EXAMPLE_URL);
setUpSnackoos();
}
diff --git a/projects/todos/app/src/main/java/io/v/todos/TodoListActivity.java b/projects/todos/app/src/main/java/io/v/todos/TodoListActivity.java
index d049da2..00535a8 100644
--- a/projects/todos/app/src/main/java/io/v/todos/TodoListActivity.java
+++ b/projects/todos/app/src/main/java/io/v/todos/TodoListActivity.java
@@ -25,7 +25,8 @@
import com.firebase.client.FirebaseError;
import com.firebase.client.ValueEventListener;
-import io.v.todos.persistence.FirebasePersistence;
+import io.v.todos.persistence.Persistence;
+import io.v.todos.persistence.PersistenceFactory;
/**
* TodoListActivity for Vanadium TODOs
@@ -40,6 +41,7 @@
* @author alexfandrianto
*/
public class TodoListActivity extends Activity {
+ private Persistence mPersistence;
private Firebase myFirebaseRef;
private final static String SNACKOO_LISTS = "snackoo lists (Task)";
@@ -58,6 +60,7 @@
protected void onDestroy() {
myFirebaseRef.removeEventListener(snackooEventListener);
myFirebaseRef.removeEventListener(snackoosEventListener);
+ mPersistence.close();
super.onDestroy();
}
@@ -99,7 +102,7 @@
}).attachToRecyclerView(recyclerView);
// Prepare our Firebase Reference and the primary listener (SNACKOOS).
- FirebasePersistence.getDatabase(this);
+ mPersistence = PersistenceFactory.getPersistence(this);
myFirebaseRef = new Firebase(MainActivity.FIREBASE_EXAMPLE_URL);
setUpSnackoo();
setUpSnackoos();
diff --git a/projects/todos/app/src/main/java/io/v/todos/persistence/FirebasePersistence.java b/projects/todos/app/src/main/java/io/v/todos/persistence/FirebasePersistence.java
index 0e11636..cd208c0 100644
--- a/projects/todos/app/src/main/java/io/v/todos/persistence/FirebasePersistence.java
+++ b/projects/todos/app/src/main/java/io/v/todos/persistence/FirebasePersistence.java
@@ -9,30 +9,31 @@
import com.firebase.client.Firebase;
/**
- * TODO(alexfandrianto): We may want to shove a lot more into this singleton and have it subclass
+ * TODO(alexfandrianto): We may want to shove a lot more into this class and have it subclass
* a common interface with Syncbase. I want this to also manage data watches and changes.
*
* @author alexfandrianto
*/
-public class FirebasePersistence {
- private FirebasePersistence() {} // Marked private to prevent accidental instantiation.
-
- private static FirebasePersistence singleton;
+public class FirebasePersistence implements Persistence {
+ static {
+ // Set up Firebase to persist data locally even when offline. This must be set before
+ // Firebase is used.
+ Firebase.getDefaultConfig().setPersistenceEnabled(true);
+ }
/**
- * Obtain a database singleton that can be used to manipulate data.
+ * Instantiates a persistence object that can be used to manipulate data.
*
- * @param context An Android context, usually from an Android activity or application.
- * @return
+ * @param context an Android context, usually from an Android activity or application
*/
- public synchronized static FirebasePersistence getDatabase(Context context) {
- if (singleton == null) {
- singleton = new FirebasePersistence();
+ public FirebasePersistence(Context context) {
+ // This no-ops if the context has already been set, and calls getApplicationContext so we
+ // don't have to worry about leaking activity contexts.
+ Firebase.setAndroidContext(context);
+ }
- // Set up Firebase with the context and have it persist data locally even when offline.
- Firebase.setAndroidContext(context);
- Firebase.getDefaultConfig().setPersistenceEnabled(true);
- }
- return singleton;
+ @Override
+ public void close() {
+ // TODO(rosswang): Remove listeners.
}
}
diff --git a/projects/todos/app/src/main/java/io/v/todos/persistence/Persistence.java b/projects/todos/app/src/main/java/io/v/todos/persistence/Persistence.java
new file mode 100644
index 0000000..7b74e2d
--- /dev/null
+++ b/projects/todos/app/src/main/java/io/v/todos/persistence/Persistence.java
@@ -0,0 +1,9 @@
+// Copyright 2016 The Vanadium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io.v.todos.persistence;
+
+public interface Persistence extends AutoCloseable {
+ void close();
+}
diff --git a/projects/todos/app/src/main/java/io/v/todos/persistence/PersistenceFactory.java b/projects/todos/app/src/main/java/io/v/todos/persistence/PersistenceFactory.java
new file mode 100644
index 0000000..104c180
--- /dev/null
+++ b/projects/todos/app/src/main/java/io/v/todos/persistence/PersistenceFactory.java
@@ -0,0 +1,21 @@
+// Copyright 2016 The Vanadium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io.v.todos.persistence;
+
+import android.content.Context;
+
+public final class PersistenceFactory {
+ private PersistenceFactory(){}
+
+ /**
+ * Instantiates a persistence object that can be used to manipulate data.
+ *
+ * @param context an Android context, usually from an Android activity or application
+ */
+ public static Persistence getPersistence(Context context) {
+ // TODO(rosswang): Choose this by build variant.
+ return new FirebasePersistence(context);
+ }
+}
diff --git a/projects/todos/app/src/main/java/io/v/todos/persistence/SyncbasePersistence.java b/projects/todos/app/src/main/java/io/v/todos/persistence/SyncbasePersistence.java
index a6ea458..80c78b8 100644
--- a/projects/todos/app/src/main/java/io/v/todos/persistence/SyncbasePersistence.java
+++ b/projects/todos/app/src/main/java/io/v/todos/persistence/SyncbasePersistence.java
@@ -4,5 +4,8 @@
package io.v.todos.persistence;
-public class SyncbasePersistence {
+public class SyncbasePersistence implements Persistence {
+ @Override
+ public void close() {
+ }
}
