Added Dagger singleton

Attempting to fix casting exceptions in threaded sync adapter and NPE
in locale

src/googleplay/java/org/tasks/injection/InjectingAbstractThreadedSyncAdapter.java

@@ -11,8 +11,8 @@ public abstract class InjectingAbstractThreadedSyncAdapter extends AbstractThrea
     }
 
     private void inject(Context context) {
-        inject(((InjectingApplication) context.getApplicationContext())
-                .getComponent()
+        inject(Dagger.get(context)
+                .getApplicationComponent()
                 .plus(new SyncAdapterModule()));
     }
 

src/main/java/org/tasks/injection/Dagger.java

@@ -0,0 +1,45 @@
+package org.tasks.injection;
+
+import android.content.Context;
+
+import org.tasks.locale.Locale;
+
+import timber.log.Timber;
+
+class Dagger {
+
+    private static final Object lock = new Object();
+
+    private static Dagger instance;
+
+    public static Dagger get(Context context) {
+        if (instance == null) {
+            synchronized (lock) {
+                if (instance == null) {
+                    instance = new Dagger(context);
+                }
+            }
+        }
+        return instance;
+    }
+
+    private ApplicationComponent applicationComponent;
+
+    private Dagger(Context context) {
+        Context localeContext = context.getApplicationContext();
+        try {
+            localeContext = Locale.getInstance(localeContext)
+                    .createConfigurationContext(localeContext);
+        } catch (Exception e) {
+            Timber.e(e.getMessage(), e);
+        }
+
+        applicationComponent = DaggerApplicationComponent.builder()
+                .applicationModule(new ApplicationModule(localeContext))
+                .build();
+    }
+
+    ApplicationComponent getApplicationComponent() {
+        return applicationComponent;
+    }
+}

src/main/java/org/tasks/injection/InjectingApplication.java

@@ -15,9 +15,7 @@ public abstract class InjectingApplication extends BaseApplication {
 
         Context context = Locale.getInstance(this).createConfigurationContext(getApplicationContext());
 
-        applicationComponent = DaggerApplicationComponent.builder()
-                .applicationModule(new ApplicationModule(context))
-                .build();
+        applicationComponent = Dagger.get(context).getApplicationComponent();
 
         inject(applicationComponent);
     }

src/main/java/org/tasks/locale/Locale.java

@@ -28,11 +28,16 @@ public class Locale {
 
     public static Locale getInstance(Context context) {
         if (INSTANCE == null) {
-            SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
-            String language = prefs.getString(context.getString(R.string.p_language), null);
-            int directionOverride = Integer.parseInt(prefs.getString(context.getString(R.string.p_layout_direction), "-1"));
-            INSTANCE = new Locale(DEFAULT.getLocale(), language, directionOverride);
-            java.util.Locale.setDefault(INSTANCE.getLocale());
+            synchronized (DEFAULT) {
+                if (INSTANCE == null) {
+                    Context applicationContext = context.getApplicationContext();
+                    SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(applicationContext);
+                    String language = prefs.getString(applicationContext.getString(R.string.p_language), null);
+                    int directionOverride = Integer.parseInt(prefs.getString(applicationContext.getString(R.string.p_layout_direction), "-1"));
+                    INSTANCE = new Locale(DEFAULT.getLocale(), language, directionOverride);
+                    java.util.Locale.setDefault(INSTANCE.getLocale());
+                }
+            }
         }
 
         return getInstance();