Use loader to load single alarm

app/src/main/java/com/philliphsu/clock2/OnBootUpAlarmScheduler.java

@@ -4,11 +4,10 @@ import android.app.IntentService;
 import android.content.Context;
 import android.content.Intent;
 
+import com.philliphsu.clock2.model.AlarmDatabaseHelper.AlarmCursor;
 import com.philliphsu.clock2.model.DatabaseManager;
 import com.philliphsu.clock2.util.AlarmUtils;
 
-import java.util.List;
-
 /**
  * An {@link IntentService} subclass for handling asynchronous task requests in
  * a service on a separate handler thread.
@@ -60,12 +59,15 @@ public class OnBootUpAlarmScheduler extends IntentService {
     @Override
     protected void onHandleIntent(Intent intent) {
         if (intent != null) {
-            List<Alarm> alarms = DatabaseManager.getInstance(this).getAlarms();
+            // IntentService already works in a background thread, so we don't need to use a loader.
-            for (Alarm a : alarms) {
+            AlarmCursor cursor = DatabaseManager.getInstance(this).queryAlarms();
-                if (a.isEnabled()) {
+            while (cursor.moveToNext()) {
-                    AlarmUtils.scheduleAlarm(this, a, false);
+                Alarm alarm = cursor.getAlarm();
+                if (alarm.isEnabled()) {
+                    AlarmUtils.scheduleAlarm(this, alarm, false);
                 }
             }
+            cursor.close();
 
 /*            final String action = intent.getAction();
             if (ACTION_FOO.equals(action)) {

app/src/main/java/com/philliphsu/clock2/editalarm/EditAlarmActivity.java

@@ -5,6 +5,8 @@ import android.media.RingtoneManager;
 import android.net.Uri;
 import android.os.Bundle;
 import android.support.annotation.StringRes;
+import android.support.v4.app.LoaderManager;
+import android.support.v4.content.Loader;
 import android.support.v7.app.ActionBar;
 import android.support.v7.widget.SwitchCompat;
 import android.text.SpannableString;
@@ -28,6 +30,7 @@ import com.philliphsu.clock2.BaseActivity;
 import com.philliphsu.clock2.DaysOfWeek;
 import com.philliphsu.clock2.R;
 import com.philliphsu.clock2.SharedPreferencesHelper;
+import com.philliphsu.clock2.model.AlarmLoader;
 import com.philliphsu.clock2.model.DatabaseManager;
 import com.philliphsu.clock2.ringtone.RingtoneActivity;
 import com.philliphsu.clock2.util.AlarmUtils;
@@ -51,7 +54,8 @@ import static com.philliphsu.clock2.util.Preconditions.checkNotNull;
 public class EditAlarmActivity extends BaseActivity implements AlarmNumpad.KeyListener,
         EditAlarmContract.View, // TODO: Remove @Override from the methods
         AlarmUtilsHelper,
-        SharedPreferencesHelper {
+        SharedPreferencesHelper,
+        LoaderManager.LoaderCallbacks<Alarm> {
     private static final String TAG = "EditAlarmActivity";
     public static final String EXTRA_ALARM_ID = "com.philliphsu.clock2.editalarm.extra.ALARM_ID";
     private static final RelativeSizeSpan AMPM_SIZE_SPAN = new RelativeSizeSpan(0.5f);
@@ -59,6 +63,7 @@ public class EditAlarmActivity extends BaseActivity implements AlarmNumpad.KeyLi
     private static final int REQUEST_PICK_RINGTONE = 0;
     private static final int ID_MENU_ITEM = 0;
 
+    private long mOldAlarmId;
     private Uri mSelectedRingtoneUri;
     private Alarm mOldAlarm;
     private DatabaseManager mDatabaseManager;
@@ -80,7 +85,17 @@ public class EditAlarmActivity extends BaseActivity implements AlarmNumpad.KeyLi
         setWeekDaysText();
         mNumpad.setKeyListener(this);
         mDatabaseManager = DatabaseManager.getInstance(this); // MUST be before loading alarm
-        loadAlarm(getIntent().getLongExtra(EXTRA_ALARM_ID, -1));
+        mOldAlarmId = getIntent().getLongExtra(EXTRA_ALARM_ID, -1);
+        if (mOldAlarmId != -1) {
+            // getLoaderManager() for support fragments by default returns the
+            // support version of LoaderManager. However, since this is an Activity,
+            // we have both the native getLoaderManager() and getSupportLoaderManager().
+            // Use the latter to remain consistent with the rest of our current code base.
+            getSupportLoaderManager().initLoader(0, null, this);
+        } else {
+            // Nothing to load, so show default values
+            showDetails();
+        }
         setTimeTextHint(); // TODO: private access
     }
 
@@ -503,11 +518,22 @@ public class EditAlarmActivity extends BaseActivity implements AlarmNumpad.KeyLi
         return AlarmUtils.readPreference(this, key, defaultValue);
     }
 
-    private void loadAlarm(long alarmId) {
+    @Override
-        mOldAlarm = alarmId > -1 ? mDatabaseManager.getAlarm(alarmId) : null;
+    public Loader<Alarm> onCreateLoader(int id, Bundle args) {
+        return new AlarmLoader(this, mOldAlarmId);
+    }
+
+    @Override
+    public void onLoadFinished(Loader<Alarm> loader, Alarm data) {
+        mOldAlarm = data;
         showDetails();
     }
 
+    @Override
+    public void onLoaderReset(Loader<Alarm> loader) {
+        // nothing to reset
+    }
+
     // TODO: Privatize access of each method called here.
     private void showDetails() {
         if (mOldAlarm != null) {

app/src/main/java/com/philliphsu/clock2/model/AlarmLoader.java

@@ -0,0 +1,23 @@
+package com.philliphsu.clock2.model;
+
+import android.content.Context;
+
+import com.philliphsu.clock2.Alarm;
+
+/**
+ * Created by Phillip Hsu on 6/30/2016.
+ */
+public class AlarmLoader extends DataLoader<Alarm> {
+
+    private long mAlarmId;
+
+    public AlarmLoader(Context context, long alarmId) {
+        super(context);
+        mAlarmId = alarmId;
+    }
+
+    @Override
+    public Alarm loadInBackground() {
+        return DatabaseManager.getInstance(getContext()).getAlarm(mAlarmId);
+    }
+}

app/src/main/java/com/philliphsu/clock2/model/DataLoader.java

@@ -0,0 +1,34 @@
+package com.philliphsu.clock2.model;
+
+import android.content.Context;
+import android.support.v4.content.AsyncTaskLoader;
+
+/**
+ * Created by Phillip Hsu on 6/30/2016.
+ */
+public abstract class DataLoader<D> extends AsyncTaskLoader<D> {
+
+    private D mData;
+
+    public DataLoader(Context context) {
+        super(context);
+    }
+
+    @Override
+    protected void onStartLoading() {
+        if (mData != null) {
+            deliverResult(mData);
+        } else {
+            forceLoad();
+        }
+    }
+
+    @Override
+    public void deliverResult(D data) {
+        mData = data;
+        if (isStarted()) {
+            super.deliverResult(data);
+        }
+    }
+
+}

app/src/main/java/com/philliphsu/clock2/util/AlarmUtils.java

@@ -21,7 +21,6 @@ import static android.app.PendingIntent.FLAG_CANCEL_CURRENT;
 import static android.app.PendingIntent.FLAG_NO_CREATE;
 import static android.app.PendingIntent.getActivity;
 import static com.philliphsu.clock2.util.DateFormatUtils.formatTime;
-import static com.philliphsu.clock2.util.Preconditions.checkNotNull;
 import static java.util.concurrent.TimeUnit.HOURS;
 
 /**
@@ -75,12 +74,16 @@ public final class AlarmUtils {
         AlarmManager am = (AlarmManager) c.getSystemService(Context.ALARM_SERVICE);
 
         PendingIntent pi = alarmIntent(c, a, true);
-        am.cancel(pi);
+        if (pi != null) {
-        pi.cancel();
+            am.cancel(pi);
+            pi.cancel();
+        }
 
         pi = notifyUpcomingAlarmIntent(c, a, true);
-        am.cancel(pi);
+        if (pi != null) {
-        pi.cancel();
+            am.cancel(pi);
+            pi.cancel();
+        }
 
         removeUpcomingAlarmNotification(c, a);
 
@@ -159,9 +162,13 @@ public final class AlarmUtils {
                 .putExtra(RingtoneActivity.EXTRA_ITEM_ID, alarm.id());
         int flag = retrievePrevious ? FLAG_NO_CREATE : FLAG_CANCEL_CURRENT;
         PendingIntent pi = getActivity(context, alarm.intId(), intent, flag);
+        // Even when we try to retrieve a previous instance that actually did exist,
+        // null can be returned for some reason.
+/*
         if (retrievePrevious) {
             checkNotNull(pi);
         }
+*/
         return pi;
     }
 
@@ -176,9 +183,13 @@ public final class AlarmUtils {
         }
         int flag = retrievePrevious ? FLAG_NO_CREATE : FLAG_CANCEL_CURRENT;
         PendingIntent pi = PendingIntent.getBroadcast(context, alarm.intId(), intent, flag);
+        // Even when we try to retrieve a previous instance that actually did exist,
+        // null can be returned for some reason.
+/*
         if (retrievePrevious) {
             checkNotNull(pi);
         }
+*/
         return pi;
     }