Handle the case that sync is active while deleting all tracks

MyTracks/src/com/google/android/apps/mytracks/DeleteAsyncTask.java

@@ -76,6 +76,16 @@ public class DeleteAsyncTask extends AsyncTask<Void, Integer, Boolean> {
     MyTracksProviderUtils myTracksProviderUtils = MyTracksProviderUtils.Factory.get(context);
 
     if (trackIds.length == 1 && trackIds[0] == -1L) {
+      try {
+        while (SyncUtils.isSyncActive(context)) {
+          if (isCancelled()) {
+            return false;
+          }
+          Thread.sleep(1000);
+        }
+      } catch (InterruptedException e) {
+        return false;
+      }
       PreferencesUtils.setBoolean(
           context, R.string.drive_sync_key, PreferencesUtils.DRIVE_SYNC_DEFAULT);
       SyncUtils.disableSync(context);
@@ -84,9 +94,10 @@ public class DeleteAsyncTask extends AsyncTask<Void, Integer, Boolean> {
       return true;
     } else {
       for (long id : trackIds) {
-        if (!isCancelled()) {
-          myTracksProviderUtils.deleteTrack(id);
+        if (isCancelled()) {
+          return false;
         }
+        myTracksProviderUtils.deleteTrack(id);
       }
       return true;
     }

MyTracks/src/com/google/android/apps/mytracks/io/sync/SyncAdapter.java

@@ -353,8 +353,12 @@ public class SyncAdapter extends AbstractThreadedSyncAdapter {
             long[] trackIds = kmlImporter.importFile(inputStream);
             if (trackIds.length == 1) {
               Track track = myTracksProviderUtils.getTrack(trackIds[0]);
-              SyncUtils.updateTrackWithDriveFileInfo(myTracksProviderUtils, track, driveFile);
-              Log.d(TAG, "Add from Google Drive " + track.getName());
+              if (track == null) {
+                Log.e(TAG, "Unable to insert new drive file for " + driveFile.getId());
+              } else {
+                SyncUtils.updateTrackWithDriveFileInfo(myTracksProviderUtils, track, driveFile);
+                Log.d(TAG, "Add from Google Drive " + track.getName());
+              } 
             } else {
               // Clean up if imported more than one track
               for (int i = 0; i < trackIds.length; i++) {
@@ -495,8 +499,12 @@ public class SyncAdapter extends AbstractThreadedSyncAdapter {
       long[] trackIds = kmlImporter.importFile(inputStream);
       if (trackIds.length == 1) {
         Track newTrack = myTracksProviderUtils.getTrack(trackIds[0]);
-        SyncUtils.updateTrackWithDriveFileInfo(myTracksProviderUtils, newTrack, driveFile);
-        return true;
+        if (newTrack == null) {
+          Log.e(TAG, "Unable to merge, imported track is null");
+        } else {
+          SyncUtils.updateTrackWithDriveFileInfo(myTracksProviderUtils, newTrack, driveFile);
+          return true;
+        }
       } else {
         Log.e(TAG, "Unable to merge, imported size is not 1");
       }

MyTracks/src/com/google/android/apps/mytracks/io/sync/SyncUtils.java

@@ -127,6 +127,21 @@ public class SyncUtils {
     }
   }
 
+  /**
+   * Returns true if sync is active.
+   * 
+   * @param context the context
+   */
+  public static boolean isSyncActive(Context context) {
+    Account[] accounts = AccountManager.get(context).getAccountsByType(Constants.ACCOUNT_TYPE);
+    for (Account account : accounts) {
+      if (ContentResolver.isSyncActive(account, SYNC_AUTHORITY)) {
+        return true;
+      }
+    }
+    return false;
+  }
+  
   /**
    * Enables sync.
    *