Merge "Improve EmailAsyncTask"

emailcommon/src/com/android/emailcommon/utility/EmailAsyncTask.java

@@ -18,14 +18,16 @@ package com.android.emailcommon.utility;
 
 import android.os.AsyncTask;
 
+import java.util.ArrayList;
 import java.util.LinkedList;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executor;
 
 /**
  * {@link AsyncTask} substitution for the email app.
  *
  * Modeled after {@link AsyncTask}; the basic usage is the same, with extra features:
- * - Bulk cancellation of multiple tasks.  This is mainly used by UI to cancell pending tasks
+ * - Bulk cancellation of multiple tasks.  This is mainly used by UI to cancel pending tasks
  *   in onDestroy() or similar places.
  * - More features to come...
  *
@@ -33,6 +35,9 @@ import java.util.concurrent.ExecutionException;
  * {@link AsyncTask#onProgressUpdate}.  Add these when necessary.
  */
 public abstract class EmailAsyncTask<Params, Progress, Result> {
+    private static final Executor SERIAL_EXECUTOR = AsyncTask.SERIAL_EXECUTOR;
+    private static final Executor PARALLEL_EXECUTOR = AsyncTask.THREAD_POOL_EXECUTOR;
+
     /**
      * Tracks {@link EmailAsyncTask}.
      *
@@ -66,9 +71,34 @@ public abstract class EmailAsyncTask<Params, Progress, Result> {
             }
         }
 
+        /**
+         * Cancel all instances of the same class as {@code current} other than
+         * {@code current} itself.
+         */
+        /* package */ void cancelOthers(EmailAsyncTask<?, ?, ?> current) {
+            final Class<?> clazz = current.getClass();
+            synchronized (mTasks) {
+                final ArrayList<EmailAsyncTask<?, ?, ?>> toRemove =
+                        new ArrayList<EmailAsyncTask<?, ?, ?>>();
+                for (EmailAsyncTask<?, ?, ?> task : mTasks) {
+                    if ((task != current) && task.getClass().equals(clazz)) {
+                        task.cancel(true);
+                        toRemove.add(task);
+                    }
+                }
+                for (EmailAsyncTask<?, ?, ?> task : toRemove) {
+                    mTasks.remove(task);
+                }
+            }
+        }
+
         /* package */ int getTaskCountForTest() {
             return mTasks.size();
         }
+
+        /* package */ boolean containsTaskForTest(EmailAsyncTask<?, ?, ?> task) {
+            return mTasks.contains(task);
+        }
     }
 
     private final Tracker mTracker;
@@ -109,46 +139,127 @@ public abstract class EmailAsyncTask<Params, Progress, Result> {
         mInnerTask = new InnerTask<Params, Progress, Result>(this);
     }
 
-    /* package */ void unregisterSelf() {
+    /* package */ final void unregisterSelf() {
         if (mTracker != null) {
             mTracker.remove(this);
         }
     }
 
+    /** @see AsyncTask#doInBackground */
     protected abstract Result doInBackground(Params... params);
 
+
+    /** @see AsyncTask#cancel(boolean) */
     public final boolean cancel(boolean mayInterruptIfRunning) {
         return mInnerTask.cancel(mayInterruptIfRunning);
     }
 
+    /** @see AsyncTask#onCancelled */
     protected void onCancelled(Result result) {
     }
 
+    /** @see AsyncTask#onPostExecute */
     protected void onPostExecute(Result result) {
     }
 
-    public final EmailAsyncTask<Params, Progress, Result> execute(Params... params) {
+    /**
-        mInnerTask.execute(params);
+     * execute on {@link #PARALLEL_EXECUTOR}
+     *
+     * @see AsyncTask#execute
+     */
+    public final EmailAsyncTask<Params, Progress, Result> executeParallel(Params... params) {
+        return executeInternal(PARALLEL_EXECUTOR, false, params);
+    }
+
+    /**
+     * execute on {@link #SERIAL_EXECUTOR}
+     *
+     * @see AsyncTask#execute
+     */
+    public final EmailAsyncTask<Params, Progress, Result> executeSerial(Params... params) {
+        return executeInternal(SERIAL_EXECUTOR, false, params);
+    }
+
+    /**
+     * Cancel all previously created instances of the same class tracked by the same
+     * {@link Tracker}, and then {@link #executeParallel}.
+     */
+    public final EmailAsyncTask<Params, Progress, Result> cancelPreviousAndExecuteParallel(
+            Params... params) {
+        return executeInternal(PARALLEL_EXECUTOR, true, params);
+    }
+
+    /**
+     * Cancel all previously created instances of the same class tracked by the same
+     * {@link Tracker}, and then {@link #executeSerial}.
+     */
+    public final EmailAsyncTask<Params, Progress, Result> cancelPreviousAndExecuteSerial(
+            Params... params) {
+        return executeInternal(SERIAL_EXECUTOR, true, params);
+    }
+
+    private final EmailAsyncTask<Params, Progress, Result> executeInternal(Executor executor,
+            boolean cancelPrevious, Params... params) {
+        if (cancelPrevious) {
+            if (mTracker == null) {
+                throw new IllegalStateException();
+            } else {
+                mTracker.cancelOthers(this);
+            }
+        }
+        mInnerTask.executeOnExecutor(executor, params);
         return this;
     }
 
-    public final Result get() throws InterruptedException, ExecutionException {
+    /**
-        return mInnerTask.get();
+     * Runs a {@link Runnable} in a bg thread, using {@link #PARALLEL_EXECUTOR}.
+     */
+    public static EmailAsyncTask<Void, Void, Void> runAsyncParallel(Runnable runnable) {
+        return runAsyncInternal(PARALLEL_EXECUTOR, runnable);
     }
 
+    /**
+     * Runs a {@link Runnable} in a bg thread, using {@link #SERIAL_EXECUTOR}.
+     */
+    public static EmailAsyncTask<Void, Void, Void> runAsyncSerial(Runnable runnable) {
+        return runAsyncInternal(SERIAL_EXECUTOR, runnable);
+    }
+
+    private static EmailAsyncTask<Void, Void, Void> runAsyncInternal(Executor executor,
+            final Runnable runnable) {
+        EmailAsyncTask<Void, Void, Void> task = new EmailAsyncTask<Void, Void, Void>(null) {
+            @Override
+            protected Void doInBackground(Void... params) {
+                runnable.run();
+                return null;
+            }
+        };
+        return task.executeInternal(executor, false, (Void[]) null);
+    }
+
+    /**
+     * Wait until {@link #doInBackground} finishes.
+     *
+     * @see AsyncTask#get
+     */
+    public final void waitForFinish() throws InterruptedException, ExecutionException {
+        mInnerTask.get();
+    }
+
+    /** @see AsyncTask#isCancelled */
     public final boolean isCancelled() {
         return mInnerTask.isCancelled();
     }
 
-    /* package */ Result callDoInBackgroundForTest(Params... params) {
+    /* package */ final Result callDoInBackgroundForTest(Params... params) {
         return mInnerTask.doInBackground(params);
     }
 
-    /* package */ void callOnCancelledForTest(Result result) {
+    /* package */ final void callOnCancelledForTest(Result result) {
         mInnerTask.onCancelled(result);
     }
 
-    /* package */ void callOnPostExecuteForTest(Result result) {
+    /* package */ final void callOnPostExecuteForTest(Result result) {
         mInnerTask.onPostExecute(result);
     }
 }

emailcommon/src/com/android/emailcommon/utility/Utility.java

@@ -573,14 +573,18 @@ public class Utility {
      * Run {@code r} on a worker thread, returning the AsyncTask
      * @return the AsyncTask; this is primarily for use by unit tests, which require the
      * result of the task
+     *
+     * @deprecated use {@link EmailAsyncTask#runAsyncParallel} or
+     *     {@link EmailAsyncTask#runAsyncSerial}
      */
+    @Deprecated
     public static AsyncTask<Void, Void, Void> runAsync(final Runnable r) {
         return new AsyncTask<Void, Void, Void>() {
             @Override protected Void doInBackground(Void... params) {
                 r.run();
                 return null;
             }
-        }.execute();
+        }.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
     }
 
     /**

src/com/android/email/activity/AccountShortcutPicker.java

@@ -19,12 +19,11 @@ package com.android.email.activity;
 import com.android.email.R;
 import com.android.emailcommon.provider.EmailContent;
 import com.android.emailcommon.provider.EmailContent.Account;
-import com.android.emailcommon.utility.Utility;
+import com.android.emailcommon.utility.EmailAsyncTask;
 
 import android.app.ListActivity;
 import android.content.Intent;
 import android.database.Cursor;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Parcelable;
 import android.view.View;
@@ -43,7 +42,7 @@ import android.widget.SimpleCursorAdapter;
 public class AccountShortcutPicker extends ListActivity
         implements OnClickListener, OnItemClickListener {
 
-    private AccountTask mAccountTask;
+    private final EmailAsyncTask.Tracker mTaskTracker = new EmailAsyncTask.Tracker();
 
     /**
      * Support for list adapter
@@ -74,16 +73,14 @@ public class AccountShortcutPicker extends ListActivity
         listView.setOnItemClickListener(this);
         listView.setItemsCanFocus(false);
 
-        mAccountTask = new AccountTask();
+        new AccountTask().executeParallel();
-        mAccountTask.execute();
     }
 
     @Override
     public void onDestroy() {
         super.onDestroy();
         // Cleanup running async task (if any)
-        Utility.cancelTaskInterrupt(mAccountTask);
+        mTaskTracker.cancellAllInterrupt();
-        mAccountTask = null;
         // Cleanup accounts cursor (if any)
         SimpleCursorAdapter adapter = (SimpleCursorAdapter) getListAdapter();
         if (adapter != null) {
@@ -114,7 +111,10 @@ public class AccountShortcutPicker extends ListActivity
     /**
      * Load the accounts and create the adapter.
      */
-    private class AccountTask extends AsyncTask<Void, Void, Cursor> {
+    private class AccountTask extends EmailAsyncTask<Void, Void, Cursor> {
+        public AccountTask() {
+            super(mTaskTracker);
+        }
 
         @Override
         protected Cursor doInBackground(Void... params) {

src/com/android/email/activity/MessageCompose.java

@@ -34,6 +34,7 @@ import com.android.emailcommon.provider.EmailContent.BodyColumns;
 import com.android.emailcommon.provider.EmailContent.Message;
 import com.android.emailcommon.provider.EmailContent.MessageColumns;
 import com.android.emailcommon.utility.AttachmentUtilities;
+import com.android.emailcommon.utility.EmailAsyncTask;
 import com.android.emailcommon.utility.Utility;
 
 import android.app.ActionBar;
@@ -48,7 +49,6 @@ import android.content.Intent;
 import android.content.pm.ActivityInfo;
 import android.database.Cursor;
 import android.net.Uri;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Parcelable;
 import android.provider.OpenableColumns;
@@ -157,8 +157,7 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
     private Controller mController;
     private boolean mDraftNeedsSaving;
     private boolean mMessageLoaded;
-    private AsyncTask<Long, Void, Attachment[]> mLoadAttachmentsTask;
+    private final EmailAsyncTask.Tracker mTaskTracker = new EmailAsyncTask.Tracker();
-    private AsyncTask<Void, Void, Object[]> mLoadMessageTask;
 
     private EmailAddressAdapter mAddressAdapterTo;
     private EmailAddressAdapter mAddressAdapterCc;
@@ -336,7 +335,7 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
             // Otherwise, handle the internal cases (Message Composer invoked from within app)
             long messageId = draftId != -1 ? draftId : intent.getLongExtra(EXTRA_MESSAGE_ID, -1);
             if (messageId != -1) {
-                mLoadMessageTask = new LoadMessageTask(messageId).execute();
+                new LoadMessageTask(messageId).executeParallel();
             } else {
                 setAccount(intent);
                 // Since this is a new message, we don't need to call LoadMessageTask.
@@ -394,10 +393,7 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
         mQuotedText.destroy();
         mQuotedText = null;
 
-        Utility.cancelTaskInterrupt(mLoadAttachmentsTask);
+        mTaskTracker.cancellAllInterrupt();
-        mLoadAttachmentsTask = null;
-        Utility.cancelTaskInterrupt(mLoadMessageTask);
-        mLoadMessageTask = null;
 
         if (mAddressAdapterTo != null) {
             mAddressAdapterTo.close();
@@ -608,10 +604,11 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
         mAddressAdapterBcc = new EmailAddressAdapter(this);
     }
 
-    private class LoadMessageTask extends AsyncTask<Void, Void, Object[]> {
+    private class LoadMessageTask extends EmailAsyncTask<Void, Void, Object[]> {
         private final long mMessageId;
 
         public LoadMessageTask(long messageId) {
+            super(mTaskTracker);
             mMessageId = messageId;
         }
 
@@ -686,7 +683,7 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
                 } else {
                     mSource = message;
                 }
-                mLoadAttachmentsTask = new AsyncTask<Long, Void, Attachment[]>() {
+                new EmailAsyncTask<Long, Void, Attachment[]>(mTaskTracker) {
                     @Override
                     protected Attachment[] doInBackground(Long... messageIds) {
                         return Attachment.restoreAttachmentsWithMessageId(MessageCompose.this,
@@ -716,7 +713,7 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
                             addAttachment(attachment, allowDelete);
                         }
                     }
-                }.execute(message.mId);
+                }.executeParallel(message.mId);
             } else if (ACTION_REPLY.equals(mAction) || ACTION_REPLY_ALL.equals(mAction)) {
                 mSource = message;
             } else if (Email.LOGD) {
@@ -909,10 +906,11 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
         }
     }
 
-    private class SendOrSaveMessageTask extends AsyncTask<Void, Void, Void> {
+    private class SendOrSaveMessageTask extends EmailAsyncTask<Void, Void, Void> {
         private final boolean mSend;
 
         public SendOrSaveMessageTask(boolean send) {
+            super(null /* DO NOT cancel in onDestroy */);
             if (send && ActivityManager.isUserAMonkey()) {
                 Log.d(Logging.LOG_TAG, "Inhibiting send while monkey is in charge.");
                 send = false;
@@ -994,9 +992,6 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
                 sSaveInProgress = false;
                 sSaveInProgressCondition.notify();
             }
-            if (isCancelled()) {
-                return;
-            }
             // Don't display the toast if the user is just changing the orientation
             if (!mSend && (getChangingConfigurations() & ActivityInfo.CONFIG_ORIENTATION) == 0) {
                 Toast.makeText(MessageCompose.this, R.string.message_saved_toast,
@@ -1020,7 +1015,7 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
         synchronized (sSaveInProgressCondition) {
             sSaveInProgress = true;
         }
-        new SendOrSaveMessageTask(send).execute();
+        new SendOrSaveMessageTask(send).executeParallel();
    }
 
     private void saveIfNeeded() {
@@ -1252,16 +1247,13 @@ public class MessageCompose extends Activity implements OnClickListener, OnFocus
         mAttachments.removeView(attachmentView);
         updateAttachmentContainer();
         if (attachment.mMessageKey == mDraft.mId && attachment.isSaved()) {
-            // The following async task for deleting attachments:
+            final long attachmentId = attachment.mId;
-            // - can be started multiple times in parallel (to delete multiple attachments).
+            EmailAsyncTask.runAsyncParallel(new Runnable() {
-            // - need not be interrupted on activity exit, instead should run to completion.
-            new AsyncTask<Long, Void, Void>() {
                 @Override
-                protected Void doInBackground(Long... attachmentIds) {
+                public void run() {
-                    mController.deleteAttachment(attachmentIds[0]);
+                    mController.deleteAttachment(attachmentId);
-                    return null;
                 }
-            }.execute(attachment.mId);
+            });
         }
         setDraftNeedsSaving(true);
     }

src/com/android/email/activity/MessageListFragment.java

@@ -28,6 +28,7 @@ import com.android.emailcommon.provider.EmailContent;
 import com.android.emailcommon.provider.EmailContent.Account;
 import com.android.emailcommon.provider.EmailContent.Mailbox;
 import com.android.emailcommon.provider.EmailContent.Message;
+import com.android.emailcommon.utility.EmailAsyncTask;
 import com.android.emailcommon.utility.Utility;
 import com.android.emailcommon.utility.Utility.ListStateSaver;
 
@@ -42,13 +43,11 @@ import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.database.Cursor;
 import android.graphics.Canvas;
-import android.graphics.Paint;
 import android.graphics.Point;
 import android.graphics.PointF;
 import android.graphics.Rect;
 import android.graphics.Typeface;
 import android.graphics.drawable.Drawable;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Parcel;
 import android.os.Parcelable;
@@ -160,7 +159,7 @@ public class MessageListFragment extends ListFragment
 
     private Utility.ListStateSaver mSavedListState;
 
-    private MessageOpenTask mMessageOpenTask;
+    private final EmailAsyncTask.Tracker mTaskTracker = new EmailAsyncTask.Tracker();
 
     /**
      * Callback interface that owning activities must implement
@@ -306,8 +305,7 @@ public class MessageListFragment extends ListFragment
         if (Email.DEBUG_LIFECYCLE && Email.DEBUG) {
             Log.d(Logging.LOG_TAG, "MessageListFragment onDestroy");
         }
-        Utility.cancelTaskInterrupt(mMessageOpenTask);
+        mTaskTracker.cancellAllInterrupt();
-        mMessageOpenTask = null;
         mRefreshManager.unregisterListener(mRefreshListener);
         super.onDestroy();
     }
@@ -637,19 +635,18 @@ public class MessageListFragment extends ListFragment
      * @param messageId ID of the msesage to open.
      */
     private void onMessageOpen(final long messageMailboxId, final long messageId) {
-        Utility.cancelTaskInterrupt(mMessageOpenTask);
+        new MessageOpenTask(messageMailboxId, messageId).cancelPreviousAndExecuteParallel();
-        mMessageOpenTask = new MessageOpenTask(messageMailboxId, messageId);
-        mMessageOpenTask.execute();
     }
 
     /**
      * Task to look up the mailbox type for a message, and kicks the callback.
      */
-    private class MessageOpenTask extends AsyncTask<Void, Void, Integer> {
+    private class MessageOpenTask extends EmailAsyncTask<Void, Void, Integer> {
         private final long mMessageMailboxId;
         private final long mMessageId;
 
         public MessageOpenTask(long messageMailboxId, long messageId) {
+            super(mTaskTracker);
             mMessageMailboxId = messageMailboxId;
             mMessageId = messageId;
         }

src/com/android/email/activity/MessageListXL.java

@@ -30,6 +30,7 @@ import com.android.emailcommon.Logging;
 import com.android.emailcommon.mail.MessagingException;
 import com.android.emailcommon.provider.EmailContent.Account;
 import com.android.emailcommon.provider.EmailContent.Mailbox;
+import com.android.emailcommon.utility.EmailAsyncTask;
 import com.android.emailcommon.utility.Utility;
 
 import android.app.ActionBar;
@@ -39,7 +40,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.Loader;
 import android.database.Cursor;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Handler;
 import android.text.TextUtils;
@@ -88,7 +88,7 @@ public class MessageListXL extends Activity implements
     private final MessageOrderManagerCallback mMessageOrderManagerCallback
             = new MessageOrderManagerCallback();
 
-    private RefreshTask mRefreshTask;
+    private final EmailAsyncTask.Tracker mTaskTracker = new EmailAsyncTask.Tracker();
 
     private BannerController mBannerController;
     private TextView mErrorMessageView;
@@ -264,7 +264,7 @@ public class MessageListXL extends Activity implements
         if (Email.DEBUG_LIFECYCLE && Email.DEBUG) Log.d(Logging.LOG_TAG, "MessageListXL onDestroy");
         mIsCreated = false;
         mController.removeResultCallback(mControllerResult);
-        Utility.cancelTaskInterrupt(mRefreshTask);
+        mTaskTracker.cancellAllInterrupt();
         mRefreshManager.unregisterListener(mMailRefreshManagerListener);
         mFragmentManager.onDestroy();
         super.onDestroy();
@@ -561,7 +561,7 @@ public class MessageListXL extends Activity implements
      * Call this when getting a connection error.
      */
     private void showErrorMessage(final String rawMessage, final long accountId) {
-        new AsyncTask<Void, Void, String>() {
+        new EmailAsyncTask<Void, Void, String>(mTaskTracker) {
             @Override
             protected String doInBackground(Void... params) {
                 Account account = Account.restoreAccountWithId(MessageListXL.this, accountId);
@@ -570,9 +570,6 @@ public class MessageListXL extends Activity implements
 
             @Override
             protected void onPostExecute(String accountName) {
-                if (!mIsCreated) {
-                    return; // activity destroyed.
-                }
                 final String message;
                 if (TextUtils.isEmpty(accountName)) {
                     message = rawMessage;
@@ -585,8 +582,7 @@ public class MessageListXL extends Activity implements
                     mLastErrorAccountId = accountId;
                 }
             }
-        }.execute();
+        }.executeParallel();
-
     }
 
     /**
@@ -776,10 +772,8 @@ public class MessageListXL extends Activity implements
 
     private void onRefresh() {
         // Cancel previously running instance if any.
-        Utility.cancelTaskInterrupt(mRefreshTask);
+        new RefreshTask(mTaskTracker, this, mFragmentManager.getActualAccountId(),
-        mRefreshTask = new RefreshTask(this, mFragmentManager.getActualAccountId(),
+                mFragmentManager.getMailboxId()).cancelPreviousAndExecuteParallel();
-                mFragmentManager.getMailboxId());
-        mRefreshTask.execute();
     }
 
     /**
@@ -795,7 +789,7 @@ public class MessageListXL extends Activity implements
      *       {@link #INBOX_AUTO_REFRESH_MIN_INTERVAL}.
      * </ul>
      */
-    /* package */ static class RefreshTask extends AsyncTask<Void, Void, Boolean> {
+    /* package */ static class RefreshTask extends EmailAsyncTask<Void, Void, Boolean> {
         private final Clock mClock;
         private final Context mContext;
         private final long mAccountId;
@@ -803,13 +797,15 @@ public class MessageListXL extends Activity implements
         private final RefreshManager mRefreshManager;
         /* package */ long mInboxId;
 
-        public RefreshTask(Context context, long accountId, long mailboxId) {
+        public RefreshTask(EmailAsyncTask.Tracker tracker, Context context, long accountId,
-            this(context, accountId, mailboxId, Clock.INSTANCE,
+                long mailboxId) {
+            this(tracker, context, accountId, mailboxId, Clock.INSTANCE,
                     RefreshManager.getInstance(context));
         }
 
-        /* package */ RefreshTask(Context context, long accountId, long mailboxId, Clock clock,
+        /* package */ RefreshTask(EmailAsyncTask.Tracker tracker, Context context, long accountId,
-                RefreshManager refreshManager) {
+                long mailboxId, Clock clock, RefreshManager refreshManager) {
+            super(tracker);
             mClock = clock;
             mContext = context;
             mRefreshManager = refreshManager;

src/com/android/email/activity/MessageViewFragmentBase.java

@@ -56,7 +56,6 @@ import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.media.MediaScannerConnection;
 import android.net.Uri;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Environment;
 import android.os.Handler;
@@ -137,11 +136,6 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
     private long mMessageId = -1;
     private Message mMessage;
 
-    private LoadMessageTask mLoadMessageTask;
-    private ReloadMessageTask mReloadMessageTask;
-    private LoadBodyTask mLoadBodyTask;
-    private LoadAttachmentsTask mLoadAttachmentsTask;
-
     private Controller mController;
     private ControllerResultUiThreadWrapper<ControllerResults> mControllerCallback;
 
@@ -206,8 +200,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
 
     private boolean mRestoredPictureLoaded;
 
-    private final EmailAsyncTask.Tracker mUpdatePreviewIconTaskTracker
+    private final EmailAsyncTask.Tracker mTaskTracker = new EmailAsyncTask.Tracker();
-            = new EmailAsyncTask.Tracker();
 
     /**
      * Zoom scales for webview.  Values correspond to {@link Preferences#TEXT_ZOOM_TINY}..
@@ -427,15 +420,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
 
     private void cancelAllTasks() {
         mMessageObserver.unregister();
-        mUpdatePreviewIconTaskTracker.cancellAllInterrupt();
+        mTaskTracker.cancellAllInterrupt();
-        Utility.cancelTaskInterrupt(mLoadMessageTask);
-        mLoadMessageTask = null;
-        Utility.cancelTaskInterrupt(mReloadMessageTask);
-        mReloadMessageTask = null;
-        Utility.cancelTaskInterrupt(mLoadBodyTask);
-        mLoadBodyTask = null;
-        Utility.cancelTaskInterrupt(mLoadAttachmentsTask);
-        mLoadAttachmentsTask = null;
     }
 
     /**
@@ -483,8 +468,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
         mLoadWhenResumed = false;
         cancelAllTasks();
         resetView();
-        mLoadMessageTask = new LoadMessageTask(true);
+        new LoadMessageTask(true).executeParallel();
-        mLoadMessageTask.execute();
     }
 
     /**
@@ -816,7 +800,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
             // assume the download won't start right away, and we make the cancel button visible
             attachment.cancelButton.setVisibility(View.GONE);
             // Create the timed task that will change the button state
-            new AsyncTask<Void, Void, Void>() {
+            new EmailAsyncTask<Void, Void, Void>(mTaskTracker) {
                 @Override
                 protected Void doInBackground(Void... params) {
                     try {
@@ -831,7 +815,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
                         attachment.cancelButton.setVisibility(View.VISIBLE);
                     }
                 }
-            }.execute();
+            }.executeParallel();
         } else {
             attachment.cancelButton.setVisibility(View.VISIBLE);
         }
@@ -966,7 +950,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
     /**
      * Async task for loading a single message outside of the UI thread
      */
-    private class LoadMessageTask extends AsyncTask<Void, Void, Message> {
+    private class LoadMessageTask extends EmailAsyncTask<Void, Void, Message> {
 
         private final boolean mOkToFetch;
         private int mMailboxType;
@@ -975,6 +959,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
          * Special constructor to cache some local info
          */
         public LoadMessageTask(boolean okToFetch) {
+            super(mTaskTracker);
             mOkToFetch = okToFetch;
         }
 
@@ -1015,7 +1000,11 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
     /**
      * Kicked by {@link MessageObserver}.  Reload the message and update the views.
      */
-    private class ReloadMessageTask extends AsyncTask<Void, Void, Message> {
+    private class ReloadMessageTask extends EmailAsyncTask<Void, Void, Message> {
+        public ReloadMessageTask() {
+            super(mTaskTracker);
+        }
+
         @Override
         protected Message doInBackground(Void... params) {
             if (!isMessageSpecified()) { // just in case
@@ -1060,7 +1049,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
     /**
      * Async task for loading a single message body outside of the UI thread
      */
-    private class LoadBodyTask extends AsyncTask<Void, Void, String[]> {
+    private class LoadBodyTask extends EmailAsyncTask<Void, Void, String[]> {
 
         private long mId;
         private boolean mErrorLoadingMessageBody;
@@ -1069,6 +1058,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
          * Special constructor to cache some local info
          */
         public LoadBodyTask(long messageId) {
+            super(mTaskTracker);
             mId = messageId;
         }
 
@@ -1112,7 +1102,11 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
      * this implementation is incomplete, as it will fail to refresh properly if the message is
      * partially loaded at this time.
      */
-    private class LoadAttachmentsTask extends AsyncTask<Long, Void, Attachment[]> {
+    private class LoadAttachmentsTask extends EmailAsyncTask<Long, Void, Attachment[]> {
+        public LoadAttachmentsTask() {
+            super(mTaskTracker);
+        }
+
         @Override
         protected Attachment[] doInBackground(Long... messageIds) {
             return Attachment.restoreAttachmentsWithMessageId(mContext, messageIds[0]);
@@ -1419,8 +1413,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
         } else {
             mControllerCallback.getWrappee().setWaitForLoadMessageId(-1);
             // Ask for body
-            mLoadBodyTask = new LoadBodyTask(message.mId);
+            new LoadBodyTask(message.mId).executeParallel();
-            mLoadBodyTask.execute();
         }
     }
 
@@ -1560,8 +1553,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
         setMessageHtml(text);
 
         // Ask for attachments after body
-        mLoadAttachmentsTask = new LoadAttachmentsTask();
+        new LoadAttachmentsTask().executeParallel(mMessage.mId);
-        mLoadAttachmentsTask.execute(mMessage.mId);
 
         mIsMessageLoadedForTest = true;
     }
@@ -1626,8 +1618,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
                         // reload UI and reload everything else too
                         // pass false to LoadMessageTask to prevent looping here
                         cancelAllTasks();
-                        mLoadMessageTask = new LoadMessageTask(false);
+                        new LoadMessageTask(false).executeParallel();
-                        mLoadMessageTask.execute();
                         break;
                     default:
                         // do nothing - we don't have a progress bar at this time
@@ -1748,14 +1739,12 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
             if (!isMessageSpecified()) {
                 return;
             }
-            Utility.cancelTaskInterrupt(mReloadMessageTask);
+            new ReloadMessageTask().cancelPreviousAndExecuteParallel();
-            mReloadMessageTask = new ReloadMessageTask();
-            mReloadMessageTask.execute();
         }
     }
 
     private void updatePreviewIcon(MessageViewAttachmentInfo attachmentInfo) {
-        new UpdatePreviewIconTask(attachmentInfo).execute();
+        new UpdatePreviewIconTask(attachmentInfo).executeParallel();
     }
 
     private class UpdatePreviewIconTask extends EmailAsyncTask<Void, Void, Bitmap> {
@@ -1764,7 +1753,7 @@ public abstract class MessageViewFragmentBase extends Fragment implements View.O
         private final MessageViewAttachmentInfo mAttachmentInfo;
 
         public UpdatePreviewIconTask(MessageViewAttachmentInfo attachmentInfo) {
-            super(mUpdatePreviewIconTaskTracker);
+            super(mTaskTracker);
             mContext = getActivity();
             mAttachmentInfo = attachmentInfo;
         }

tests/src/com/android/email/activity/MessageListXLRefreshTaskTest.java

@@ -57,8 +57,8 @@ public class MessageListXLRefreshTaskTest extends AndroidTestCase {
         final long ACCOUNT_ID = 5;
         final long MAILBOX_ID = 10;
 
-        MessageListXL.RefreshTask task = new MessageListXL.RefreshTask(getContext(), ACCOUNT_ID,
+        MessageListXL.RefreshTask task = new MessageListXL.RefreshTask(null, getContext(),
-                MAILBOX_ID, mClock, mRefreshManager);
+                ACCOUNT_ID, MAILBOX_ID, mClock, mRefreshManager);
 
         mRefreshManager.mExpectedAccountId = ACCOUNT_ID;
 
@@ -100,8 +100,8 @@ public class MessageListXLRefreshTaskTest extends AndroidTestCase {
         final long ACCOUNT_ID = 5;
         final long MAILBOX_ID = 10;
 
-        MessageListXL.RefreshTask task = new MessageListXL.RefreshTask(getContext(), ACCOUNT_ID,
+        MessageListXL.RefreshTask task = new MessageListXL.RefreshTask(null, getContext(),
-                MAILBOX_ID, mClock, mRefreshManager);
+                ACCOUNT_ID, MAILBOX_ID, mClock, mRefreshManager);
 
         mRefreshManager.mExpectedAccountId = ACCOUNT_ID;
 

tests/src/com/android/emailcommon/utility/EmailAsyncTaskTests.java

@@ -16,6 +16,8 @@
 
 package com.android.emailcommon.utility;
 
+import com.android.emailcommon.utility.EmailAsyncTask.Tracker;
+
 import android.test.AndroidTestCase;
 import android.test.MoreAsserts;
 
@@ -82,6 +84,37 @@ public class EmailAsyncTaskTests extends AndroidTestCase {
         task1.unregisterSelf();
     }
 
+    /**
+     * Test for {@link EmailAsyncTask.Tracker#cancelOthers}
+     */
+    public void testCancellOthers() {
+        final EmailAsyncTask.Tracker tracker = new EmailAsyncTask.Tracker();
+
+        final MyTask task1 = new MyTask(tracker);
+        final MyTask task2 = new MyTask(tracker);
+        final MyTask task3 = new MyTask(tracker);
+
+        final MyTask sub1 = new MyTaskSubClass(tracker);
+        final MyTask sub2 = new MyTaskSubClass(tracker);
+        final MyTask sub3 = new MyTaskSubClass(tracker);
+
+        // All should be in the tracker.
+        assertEquals(6, tracker.getTaskCountForTest());
+
+        // This should remove task1, task2, but not task3 itself.
+        tracker.cancelOthers(task3);
+
+        assertEquals(4, tracker.getTaskCountForTest());
+        assertTrue(tracker.containsTaskForTest(task3));
+
+        // Same for sub1.
+        tracker.cancelOthers(sub1);
+
+        assertEquals(2, tracker.getTaskCountForTest());
+        assertTrue(tracker.containsTaskForTest(task3));
+        assertTrue(tracker.containsTaskForTest(sub1));
+    }
+
     private static class MyTask extends EmailAsyncTask<String, String, String> {
         public String[] mDoInBackgroundArg;
         public String mDoInBackgroundResult;
@@ -108,4 +141,10 @@ public class EmailAsyncTaskTests extends AndroidTestCase {
             mOnPostExecuteArg = result;
         }
     }
+
+    private static class MyTaskSubClass extends MyTask {
+        public MyTaskSubClass(Tracker tracker) {
+            super(tracker);
+        }
+    }
 }