Add support to backup the preferences on Froyo.

src/org/r3pek/pharmacies/MyPreferences.java

@@ -1,18 +1,37 @@
 package org.r3pek.pharmacies;
 
+import org.r3pek.pharmacies.backup.WrapBackupManager;
 import org.r3pek.pharmacies.widgets.SeekBarPreference;
 
 import android.os.Bundle;
 import android.preference.PreferenceActivity;
+import android.util.Log;
 
 public class MyPreferences extends PreferenceActivity {
+    private static boolean isRunningInFroyo;
+    /* establish whether the "new" class is available to us */
+    static {
+        try {
+            WrapBackupManager.isAvailable();
+            isRunningInFroyo = true;
+        } catch (Throwable t) {
+            isRunningInFroyo = false;
+        }
+    }
 
     public void onCreate(Bundle savedInstanceState) {
 		super.onCreate(savedInstanceState);
-
 		addPreferencesFromResource(R.xml.preferences);
 		
 		SeekBarPreference sbp = (SeekBarPreference) findPreference("pref_gen_maxdist");
 		sbp.setMin(1);
-    }    
+    }
+    
+    @Override
+    public void onStop() {
+        super.onStop();
+        
+        if (isRunningInFroyo)
+            WrapBackupManager.dataChanged(getPackageName());
+    }
 }

src/org/r3pek/pharmacies/backup/MyBackupAgent.java

@@ -0,0 +1,18 @@
+package org.r3pek.pharmacies.backup;
+
+import android.app.backup.BackupAgentHelper;
+import android.app.backup.SharedPreferencesBackupHelper;
+
+public class MyBackupAgent extends BackupAgentHelper {
+    // A key to uniquely identify the set of backup data
+    private static final String PREFS_BACKUP_KEY = "prefs";
+
+    public void onCreate() {
+        // Ugly hack, but I can't get the defaultSharedPreferences filename elsewhere
+        final String PREFS_NAME = getPackageName() + "_preferences"; 
+        
+        SharedPreferencesBackupHelper helper = new SharedPreferencesBackupHelper(this, PREFS_NAME);
+        addHelper(PREFS_BACKUP_KEY, helper);
+    }
+    
+}