import com.owncloud.android.R;
 import com.owncloud.android.authentication.AccountUtils;
 import com.owncloud.android.authentication.AuthenticatorActivity;
+import com.owncloud.android.authentication.PinCheck;
 import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
 import com.owncloud.android.db.DbHandler;
 import com.owncloud.android.ui.RadioButtonPreference;
 import com.owncloud.android.utils.DisplayUtils;
 
-import java.io.File;
-
 
 /**
  * An Activity that allows the user to change the application's settings.
 
         // For adding content description tag to a title field in the action bar
         int actionBarTitleId = getResources().getIdentifier("action_bar_title", "id", "android");
-        getWindow().getDecorView().findViewById(actionBarTitleId).setContentDescription(getString(R.string.actionbar_settings));
+        View actionBarTitleView = getWindow().getDecorView().findViewById(actionBarTitleId);
+        if (actionBarTitleView != null) {    // it's null in Android 2.x
+            getWindow().getDecorView().findViewById(actionBarTitleId).
+                    setContentDescription(getString(R.string.actionbar_settings));
+        }
 
         // Load the accounts category for adding the list of accounts
         mAccountsPrefCategory = (PreferenceCategory) findPreference("accounts_category");
     @Override
     protected void onPause() {
         super.onPause();
+        
+        PinCheck.setUnlockTimestamp();
     }
 
     @Override
                                             FileDisplayActivity.class
                                     );
                                     i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
+                                    i.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
                                     startActivity(i);
                                 } else {
                                     finish();