Refactor Tasks for better testability

app/src/main/java/org/isoron/uhabits/tasks/BaseTask.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2016 Álinson Santos Xavier <isoron@gmail.com>
+ *
+ * This file is part of Loop Habit Tracker.
+ *
+ * Loop Habit Tracker is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * Loop Habit Tracker is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.isoron.uhabits.tasks;
+
+import android.os.AsyncTask;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+public class BaseTask extends AsyncTask<Void, Void, Void>
+{
+    private static CountDownLatch latch;
+    private static int activeTaskCount;
+
+    @Override
+    protected Void doInBackground(Void... params)
+    {
+        return null;
+    }
+
+    @Override
+    protected void onPreExecute()
+    {
+        activeTaskCount++;
+        latch = new CountDownLatch(activeTaskCount);
+    }
+
+    @Override
+    protected void onPostExecute(Void aVoid)
+    {
+        activeTaskCount--;
+        latch.countDown();
+    }
+
+    public static void waitForTasks(long timeout, TimeUnit unit)
+            throws TimeoutException, InterruptedException
+    {
+        if(activeTaskCount == 0) return;
+
+        boolean successful = latch.await(timeout, unit);
+        if(!successful) throw new TimeoutException();
+    }
+}

app/src/main/java/org/isoron/uhabits/tasks/ExportCSVTask.java

@@ -32,7 +32,7 @@ import java.io.File;
 import java.io.IOException;
 import java.util.List;
 
-public class ExportCSVTask extends AsyncTask<Void, Void, Void>
+public class ExportCSVTask extends BaseTask
 {
     public interface Listener
     {
@@ -58,6 +58,8 @@ public class ExportCSVTask extends AsyncTask<Void, Void, Void>
     @Override
     protected void onPreExecute()
     {
+        super.onPreExecute();
+
         if(progressBar != null)
         {
             progressBar.setIndeterminate(true);
@@ -73,6 +75,8 @@ public class ExportCSVTask extends AsyncTask<Void, Void, Void>
 
         if(progressBar != null)
             progressBar.setVisibility(View.GONE);
+
+        super.onPostExecute(null);
     }
 
     @Override

app/src/main/java/org/isoron/uhabits/tasks/ExportDBTask.java

@@ -29,7 +29,7 @@ import org.isoron.uhabits.helpers.DatabaseHelper;
 import java.io.File;
 import java.io.IOException;
 
-public class ExportDBTask extends AsyncTask<Void, Void, Void>
+public class ExportDBTask extends BaseTask
 {
     public interface Listener
     {
@@ -53,6 +53,8 @@ public class ExportDBTask extends AsyncTask<Void, Void, Void>
     @Override
     protected void onPreExecute()
     {
+        super.onPreExecute();
+
         if(progressBar != null)
         {
             progressBar.setIndeterminate(true);
@@ -68,6 +70,8 @@ public class ExportDBTask extends AsyncTask<Void, Void, Void>
         
         if(progressBar != null)
             progressBar.setVisibility(View.GONE);
+
+        super.onPostExecute(null);
     }
 
     @Override

app/src/main/java/org/isoron/uhabits/tasks/ImportDataTask.java

@@ -29,7 +29,7 @@ import org.isoron.uhabits.io.GenericImporter;
 
 import java.io.File;
 
-public class ImportDataTask extends AsyncTask<Void, Void, Void>
+public class ImportDataTask extends BaseTask
 {
     public static final int SUCCESS = 1;
     public static final int NOT_RECOGNIZED = 2;
@@ -65,6 +65,8 @@ public class ImportDataTask extends AsyncTask<Void, Void, Void>
     @Override
     protected void onPreExecute()
     {
+        super.onPreExecute();
+
         if(progressBar != null)
         {
             progressBar.setIndeterminate(true);
@@ -79,6 +81,8 @@ public class ImportDataTask extends AsyncTask<Void, Void, Void>
             progressBar.setVisibility(View.GONE);
 
         if(listener != null) listener.onImportFinished(result);
+
+        super.onPostExecute(null);
     }
 
     @Override

app/src/main/java/org/isoron/uhabits/views/ScrollableDataView.java

@@ -25,6 +25,7 @@ import android.util.AttributeSet;
 import android.view.GestureDetector;
 import android.view.MotionEvent;
 import android.view.View;
+import android.view.ViewParent;
 import android.widget.Scroller;
 
 public abstract class ScrollableDataView extends View implements GestureDetector.OnGestureListener,
@@ -89,7 +90,10 @@ public abstract class ScrollableDataView extends View implements GestureDetector
             return false;
 
         if(Math.abs(dx) > Math.abs(dy))
-            getParent().requestDisallowInterceptTouchEvent(true);
+        {
+            ViewParent parent = getParent();
+            if(parent != null) parent.requestDisallowInterceptTouchEvent(true);
+        }
 
         scroller.startScroll(scroller.getCurrX(), scroller.getCurrY(), (int) -dx, (int) dy, 0);
         scroller.computeScrollOffset();