Merge pull request #1471 from matham/toggle_behavior

Add a ToggleButton type behavior

kivy/uix/behaviors.py

@@ -19,10 +19,11 @@ do::
 
 '''
 
-__all__ = ('ButtonBehavior', )
+__all__ = ('ButtonBehavior', 'ToggleButtonBehavior')
 
 from kivy.clock import Clock
-from kivy.properties import OptionProperty
+from kivy.properties import OptionProperty, ObjectProperty
+from weakref import ref
 
 
 class ButtonBehavior(object):
@@ -44,7 +45,6 @@ class ButtonBehavior(object):
     :data:`state` is an :class:`~kivy.properties.OptionProperty`.
     '''
 
-
     def __init__(self, **kwargs):
         self.register_event_type('on_press')
         self.register_event_type('on_release')
@@ -106,6 +106,7 @@ class ButtonBehavior(object):
         '''
         self._do_press()
         self.dispatch('on_press')
+
         def trigger_release(dt):
             self._do_release()
             self.dispatch('on_release')
@@ -114,3 +115,92 @@ class ButtonBehavior(object):
         else:
             Clock.schedule_once(trigger_release, duration)
 
+
+class ToggleButtonBehavior(ButtonBehavior):
+    '''ToggleButton behavior, see ToggleButton module documentation for more
+    information.
+
+    .. versionadded:: 1.8.0
+    '''
+
+    __groups = {}
+
+    group = ObjectProperty(None, allownone=True)
+    '''Group of the button. If None, no group will be used (button is
+    independent). If specified, :data:`group` must be a hashable object, like
+    a string. Only one button in a group can be in 'down' state.
+
+    :data:`group` is a :class:`~kivy.properties.ObjectProperty`
+    '''
+
+    def __init__(self, **kwargs):
+        self._previous_group = None
+        super(ToggleButtonBehavior, self).__init__(**kwargs)
+
+    def on_group(self, *largs):
+        groups = ToggleButtonBehavior.__groups
+        if self._previous_group:
+            group = groups[self._previous_group]
+            for item in group[:]:
+                if item() is self:
+                    group.remove(item)
+                    break
+        group = self._previous_group = self.group
+        if group not in groups:
+            groups[group] = []
+        r = ref(self, ToggleButtonBehavior._clear_groups)
+        groups[group].append(r)
+
+    def _release_group(self, current):
+        if self.group is None:
+            return
+        group = self.__groups[self.group]
+        for item in group[:]:
+            widget = item()
+            if widget is None:
+                group.remove(item)
+            if widget is current:
+                continue
+            widget.state = 'normal'
+
+    def _do_press(self):
+        self._release_group(self)
+        self.state = 'normal' if self.state == 'down' else 'down'
+
+    def _do_release(self):
+        pass
+
+    @staticmethod
+    def _clear_groups(wk):
+        # auto flush the element when the weak reference have been deleted
+        groups = ToggleButtonBehavior.__groups
+        for group in list(groups.values()):
+            if wk in group:
+                group.remove(wk)
+                break
+
+    @staticmethod
+    def get_widgets(groupname):
+        '''Return the widgets contained in a specific group. If the group
+        doesn't exist, an empty list will be returned.
+
+        .. important::
+
+            Always release the result of this method! In doubt, do::
+
+                l = ToggleButtonBehavior.get_widgets('mygroup')
+                # do your job
+                del l
+
+        .. warning::
+
+            It's possible that some widgets that you have previously deleted are
+            still in the list. Garbage collector might need more elements before
+            flushing it. The return of this method is informative, you've been
+            warned!
+        '''
+        groups = ToggleButtonBehavior.__groups
+        if groupname not in groups:
+            return []
+        return [x() for x in groups[groupname] if x()][:]
+

kivy/uix/togglebutton.py

@@ -23,95 +23,13 @@ for a Button class.
 
 __all__ = ('ToggleButton', )
 
-from weakref import ref
 from kivy.uix.button import Button
-from kivy.properties import ObjectProperty
+from kivy.uix.behaviors import ToggleButtonBehavior
 
 
-class ToggleButton(Button):
+class ToggleButton(ToggleButtonBehavior, Button):
     '''Toggle button class, see module documentation for more information.
     '''
 
-    __groups = {}
-
-    group = ObjectProperty(None, allownone=True)
-    '''Group of the button. If None, no group will be used (button is
-    independent). If specified, :data:`group` must be a hashable object, like
-    a string. Only one button in a group can be in 'down' state.
-
-    :data:`group` is a :class:`~kivy.properties.ObjectProperty`
-    '''
-
-    def __init__(self, **kwargs):
-        self._previous_group = None
-        super(ToggleButton, self).__init__(**kwargs)
-
-    def on_group(self, *largs):
-        groups = ToggleButton.__groups
-        if self._previous_group:
-            group = groups[self._previous_group]
-            for item in group[:]:
-                if item() is self:
-                    group.remove(item)
-                    break
-        group = self._previous_group = self.group
-        if group not in groups:
-            groups[group] = []
-        r = ref(self, ToggleButton._clear_groups)
-        groups[group].append(r)
-
-    def _release_group(self, current):
-        if self.group is None:
-            return
-        group = self.__groups[self.group]
-        for item in group[:]:
-            widget = item()
-            if widget is None:
-                group.remove(item)
-            if widget is current:
-                continue
-            widget.state = 'normal'
-
-    def _do_press(self):
-        self._release_group(self)
-        self.state = 'normal' if self.state == 'down' else 'down'
-
-    def _do_release(self):
-        pass
-
-    @staticmethod
-    def _clear_groups(wk):
-        # auto flush the element when the weak reference have been deleted
-        groups = ToggleButton.__groups
-        for group in list(groups.values()):
-            if wk in group:
-                group.remove(wk)
-                break
-
-    @staticmethod
-    def get_widgets(groupname):
-        '''Return the widgets contained in a specific group. If the group
-        doesn't exist, an empty list will be returned.
-
-        .. important::
-
-            Always release the result of this method! In doubt, do::
-
-                l = ToggleButton.get_widgets('mygroup')
-                # do your job
-                del l
-
-        .. warning::
-
-            It's possible that some widgets that you have previously deleted are
-            still in the list. Garbage collector might need more elements before
-            flushing it. The return of this method is informative, you've been
-            warned!
-
-        .. versionadded:: 1.3.0
-        '''
-        groups = ToggleButton.__groups
-        if groupname not in groups:
-            return []
-        return [x() for x in groups[groupname] if x()][:]
+    pass