frontends (xmlui): new widget_value dict to get first value of widget by name

frontends/src/tools/xmlui.py

@@ -313,6 +313,20 @@ class XMLUIBase(object):
         raise NotImplementedError
 
 
+class ValueGetter(object):
+    """dict like object which return values of widgets"""
+
+    def __init__(self, widgets, attr='value'):
+        self.attr = attr
+        self.widgets = widgets
+
+    def __getitem__(self, name):
+        return getattr(self.widgets[name], self.attr)
+
+    def __getattr__(self, name):
+        return self.__getitem__(name)
+
+
 class XMLUIPanel(XMLUIBase):
     """XMLUI Panel
 
@@ -323,9 +337,14 @@ class XMLUIPanel(XMLUIBase):
     widget_factory = None
 
     def __init__(self, host, parsed_dom, title=None, flags=None, callback=None, profile=C.PROF_KEY_NONE):
+        """
+        @property widgets(dict): widget name => widget map
+        @property widget_value(ValueGetter): retrieve widget value from it's name
+        """
         super(XMLUIPanel, self).__init__(host, parsed_dom, title=title, flags=flags, callback=callback, profile=profile)
         self.ctrl_list = {}  # input widget, used mainly for forms
         self.widgets = {}  # allow to access any named widgets
+        self.widget_value = ValueGetter(self.widgets)
         self._main_cont = None
         self.constructUI(parsed_dom)