When backing/restoring prefereneces, do not include preferences for

the current device session.

MyTracks/res/values/keys.xml

@@ -22,7 +22,6 @@ limitations under the License.
   <string name="ant_combined_bike_sensor_id_key">antCombinedBikeSensorId</string>
   <string name="ant_heart_rate_monitor_id_key">antHeartRateMonitorId</string>
   <string name="ant_speed_distance_monitor_id_key">antSpeedDistanceMonitorId</string>
-  <string name="auto_resume_track_current_retry_key">autoResumeTrackCurrentRetry</string>
   <string name="auto_resume_track_timeout_key">autoResumeTrackTimeout</string>
   <string name="bluetooth_sensor_key">bluetoothSensor</string>
   <string name="chart_by_distance_key">chartByDistance</string>
@@ -40,10 +39,7 @@ limitations under the License.
   <string name="min_recording_interval_key">minRecordingInterval</string>
   <string name="min_required_accuracy_key">minRequiredAccuracy</string>
   <string name="pick_existing_map_key">pickExistingMap</string>
-  <string name="recording_track_id_key">recordingTrackId</string>
-  <string name="recording_track_paused_key">recordingTrackPaused</string>
   <string name="report_speed_key">reportSpeed</string>
-  <string name="selected_track_id_key">selectedTrackId</string>
   <string name="send_to_docs_key">sendToDocs</string>
   <string name="send_to_fusion_tables_key">sendToFusionTables</string>
   <string name="send_to_maps_key">sendToMaps</string>
@@ -59,6 +55,13 @@ limitations under the License.
   <string name="track_color_mode_slow_key">trackColorModeSlow</string>
   <string name="track_color_mode_key">trackColorMode</string>
   <string name="track_name_key">trackName</string>
+  
+  <!-- Keys for persistend preferences. But they should not get backed up or restored. -->
+  <string name="auto_resume_track_current_retry_key">autoResumeTrackCurrentRetry</string>
+  <string name="recording_track_id_key">recordingTrackId</string>
+  <string name="recording_track_paused_key">recordingTrackPaused</string>
+  <string name="selected_track_id_key">selectedTrackId</string>
+
   <!-- Keys for non-persisted preferences. Sorted alphabetically. DO NOT TRANSLATE. -->
   <string name="settings_backup_key">settingsBackup</string>
   <string name="settings_backup_now_key">settingsBackupNow</string>

MyTracks/src/com/google/android/apps/mytracks/io/backup/ExternalFileBackup.java

@@ -150,7 +150,7 @@ class ExternalFileBackup {
         "Writing backup to file " + outputFile.getAbsolutePath());
 
     // Create all the auxiliary classes that will do the writing
-    PreferenceBackupHelper preferencesHelper = new PreferenceBackupHelper();
+    PreferenceBackupHelper preferencesHelper = new PreferenceBackupHelper(context);
     DatabaseDumper trackDumper = new DatabaseDumper(
         TracksColumns.COLUMNS,
         TracksColumns.COLUMN_TYPES,
@@ -223,7 +223,7 @@ class ExternalFileBackup {
     Log.d(Constants.TAG,
         "Restoring from file " + inputFile.getAbsolutePath());
 
-    PreferenceBackupHelper preferencesHelper = new PreferenceBackupHelper();
+    PreferenceBackupHelper preferencesHelper = new PreferenceBackupHelper(context);
     ContentResolver resolver = context.getContentResolver();
     DatabaseImporter trackImporter =
         new DatabaseImporter(TracksColumns.CONTENT_URI, resolver, false);

MyTracks/src/com/google/android/apps/mytracks/io/backup/MyTracksBackupAgent.java

@@ -59,7 +59,7 @@ public class MyTracksBackupAgent extends BackupAgent {
   }
 
   protected PreferenceBackupHelper createPreferenceBackupHelper() {
-    return new PreferenceBackupHelper();
+    return new PreferenceBackupHelper(this);
   }
 
   @Override

MyTracks/src/com/google/android/apps/mytracks/io/backup/PreferenceBackupHelper.java

@@ -17,7 +17,9 @@ package com.google.android.apps.mytracks.io.backup;
 
 import com.google.android.apps.mytracks.content.ContentTypeIds;
 import com.google.android.apps.mytracks.util.ApiAdapterFactory;
+import com.google.android.maps.mytracks.R;
 
+import android.content.Context;
 import android.content.SharedPreferences;
 import android.content.SharedPreferences.Editor;
 
@@ -26,26 +28,36 @@ import java.io.ByteArrayOutputStream;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
+import java.util.HashSet;
 import java.util.Map;
 
 /**
  * Helper for backing up and restoring shared preferences.
- *
+ * 
  * @author Rodrigo Damazio
  */
-class PreferenceBackupHelper {
+public class PreferenceBackupHelper {
 
   private static final int BUFFER_SIZE = 2048;
 
+  private final HashSet<String> doNotBackup;
+
+  public PreferenceBackupHelper(Context context) {
+    doNotBackup = new HashSet<String>();
+    doNotBackup.add(context.getString(R.string.auto_resume_track_current_retry_key));
+    doNotBackup.add(context.getString(R.string.recording_track_id_key));
+    doNotBackup.add(context.getString(R.string.recording_track_paused_key));
+    doNotBackup.add(context.getString(R.string.selected_track_id_key));
+  }
+
   /**
    * Exports all shared preferences from the given object as a byte array.
-   *
+   * 
    * @param preferences the preferences to export
    * @return the corresponding byte array
    * @throws IOException if there are any errors while writing to the byte array
    */
-  public byte[] exportPreferences(SharedPreferences preferences)
-      throws IOException {
+  public byte[] exportPreferences(SharedPreferences preferences) throws IOException {
     ByteArrayOutputStream bufStream = new ByteArrayOutputStream(BUFFER_SIZE);
     DataOutputStream outWriter = new DataOutputStream(bufStream);
     exportPreferences(preferences, outWriter);
@@ -56,16 +68,18 @@ class PreferenceBackupHelper {
   /**
    * Exports all shared preferences from the given object into the given output
    * stream.
-   *
+   * 
    * @param preferences the preferences to export
    * @param outWriter the stream to write them to
    * @throws IOException if there are any errors while writing the output
    */
-  public void exportPreferences(
-      SharedPreferences preferences,
-      DataOutputStream outWriter) throws IOException {
+  public void exportPreferences(SharedPreferences preferences, DataOutputStream outWriter)
+      throws IOException {
     Map<String, ?> values = preferences.getAll();
 
+    for (String name : doNotBackup) {
+      values.remove(name);
+    }
     outWriter.writeInt(values.size());
     for (Map.Entry<String, ?> entry : values.entrySet()) {
       writePreference(entry.getKey(), entry.getValue(), outWriter);
@@ -75,13 +89,12 @@ class PreferenceBackupHelper {
 
   /**
    * Imports all preferences from the given byte array.
-   *
+   * 
    * @param data the byte array to read preferences from
    * @param preferences the shared preferences to edit
    * @throws IOException if there are any errors while reading
    */
-  public void importPreferences(byte[] data, SharedPreferences preferences)
-      throws IOException {
+  public void importPreferences(byte[] data, SharedPreferences preferences) throws IOException {
     ByteArrayInputStream bufStream = new ByteArrayInputStream(data);
     DataInputStream reader = new DataInputStream(bufStream);
 
@@ -90,13 +103,13 @@ class PreferenceBackupHelper {
 
   /**
    * Imports all preferences from the given stream.
-   *
+   * 
    * @param reader the stream to read from
    * @param preferences the shared preferences to edit
    * @throws IOException if there are any errors while reading
    */
-  public void importPreferences(DataInputStream reader,
-      SharedPreferences preferences) throws IOException {
+  public void importPreferences(DataInputStream reader, SharedPreferences preferences)
+      throws IOException {
     Editor editor = preferences.edit();
     editor.clear();
 
@@ -111,37 +124,57 @@ class PreferenceBackupHelper {
 
   /**
    * Reads a single preference and sets it into the given editor.
-   *
+   * 
    * @param name the name of the preference to read
    * @param typeId the type ID of the preference to read
    * @param reader the reader to read from
    * @param editor the editor to set the preference in
    * @throws IOException if there are errors while reading
    */
-  private void readAndSetPreference(String name, byte typeId,
-      DataInputStream reader, Editor editor) throws IOException {
+  private void readAndSetPreference(String name, byte typeId, DataInputStream reader, Editor editor)
+      throws IOException {
+
+    boolean save = true;
+    if (doNotBackup.contains(name)) {
+      save = false;
+    }
     switch (typeId) {
       case ContentTypeIds.BOOLEAN_TYPE_ID:
-        editor.putBoolean(name, reader.readBoolean());
+        boolean booleanValue = reader.readBoolean();
+        if (save) {
+          editor.putBoolean(name, booleanValue);
+        }
         return;
       case ContentTypeIds.LONG_TYPE_ID:
-        editor.putLong(name, reader.readLong());
+        long longValue = reader.readLong();
+        if (save) {
+          editor.putLong(name, longValue);
+        }
         return;
       case ContentTypeIds.FLOAT_TYPE_ID:
-        editor.putFloat(name, reader.readFloat());
+        float floatValue = reader.readFloat();
+        if (save) {
+          editor.putFloat(name, floatValue);
+        }
         return;
       case ContentTypeIds.INT_TYPE_ID:
-        editor.putInt(name, reader.readInt());
+        int intValue = reader.readInt();
+        if (save) {
+          editor.putInt(name, intValue);
+        }
         return;
       case ContentTypeIds.STRING_TYPE_ID:
-        editor.putString(name, reader.readUTF());
+        String utfValue = reader.readUTF();
+        if (save) {
+          editor.putString(name, utfValue);
+        }
         return;
     }
   }
 
   /**
    * Writes a single preference.
-   *
+   * 
    * @param name the name of the preference to write
    * @param value the correctly-typed value of the preference
    * @param writer the writer to write to
@@ -167,8 +200,7 @@ class PreferenceBackupHelper {
       writer.writeByte(ContentTypeIds.STRING_TYPE_ID);
       writer.writeUTF((String) value);
     } else {
-      throw new IllegalArgumentException(
-          "Type " + value.getClass().getName() + " not supported");
+      throw new IllegalArgumentException("Type " + value.getClass().getName() + " not supported");
     }
   }
 }

MyTracksTest/src/com/google/android/apps/mytracks/io/backup/PreferenceBackupHelperTest.java

@@ -18,19 +18,18 @@ package com.google.android.apps.mytracks.io.backup;
 import android.annotation.TargetApi;
 import android.content.SharedPreferences;
 import android.content.SharedPreferences.Editor;
+import android.test.AndroidTestCase;
 
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
 
-import junit.framework.TestCase;
-
 /**
  * Tests for {@link PreferenceBackupHelper}.
  *
  * @author Rodrigo Damazio
  */
-public class PreferenceBackupHelperTest extends TestCase {
+public class PreferenceBackupHelperTest extends AndroidTestCase {
   private Map<String, ?> preferenceValues;
   private SharedPreferences preferences;
   private PreferenceBackupHelper preferenceBackupHelper;
@@ -173,7 +172,7 @@ public class PreferenceBackupHelperTest extends TestCase {
 
     preferenceValues = new HashMap<String, Object>();
     preferences = new MockPreferences();
-    preferenceBackupHelper = new PreferenceBackupHelper();
+    preferenceBackupHelper = new PreferenceBackupHelper(getContext());
   }
 
   @TargetApi(9)