added single checkbox widget that can substitute for Toggle

kabuki/widgets.py

@@ -0,0 +1,28 @@
+from bokeh.models import CheckboxGroup
+from .buki import Object
+from .utils import adjust_margin
+
+
+class Checkbox(Object):
+
+    def __init__(self, *args, label=None, **kwargs):
+        labels = [label] if label is not None else None
+        cg = CheckboxGroup(*args, labels=labels, **kwargs)
+        adjust_margin(cg, left=5)
+        super().__init__(cg)
+
+    @property
+    def active(self):
+        return bool(self.layout.active)
+
+    @active.setter
+    def active(self, value):
+        self.layout.active = [0] if value else []
+
+    def on_click(self, handler):
+        def wrapper(state):
+            handler(bool(state))
+        self.layout.on_click(wrapper)
+
+
+