diff --git a/xray_vision/qt_widgets/__init__.py b/xray_vision/qt_widgets/__init__.py
index 165290f..f6d8088 100644
--- a/xray_vision/qt_widgets/__init__.py
+++ b/xray_vision/qt_widgets/__init__.py
@@ -41,6 +41,7 @@
 import logging
 logger = logging.getLogger(__name__)
 
+
 class CrossSectionMainWindow(QtGui.QMainWindow):
     """
     MainWindow
@@ -100,6 +101,17 @@ def __init__(self, data_list, key_list,
         # trigger the image to draw
         self._messenger.sl_update_image(0)
 
+        self.key_list = key_list
+
+        def add_data(self, new_data, new_key_names):
+            old_length = len(self.key_list)
+            for key in new_key_names:
+                self.key_list.append(key)
+            for i in range(old_length, len(self.key_list)):
+                self._messenger._view._data_dict[self.key_list[i]] = new_data[i-old_length]
+            self._messenger._ctrl_widget._slider_img.setMaximum(len(self.key_list)-1)
+            self._messenger._ctrl_widget._spin_img.setMaximum(len(self.key_list)-1)
+
 
 class Stack1DMainWindow(QtGui.QMainWindow):
     """