add disconnect to elements, and disconnect renderer from sources on screen close
[enigma2.git] / lib / python / Components / Element.py
index 6f812b2..fc70913 100644 (file)
@@ -25,6 +25,24 @@ class Element:
                self.connectUpstream(upstream)
                upstream.connectDownstream(self)
 
+       # we disconnect from down to up
+       def disconnectAll(self):
+               # we should not disconnect from upstream if
+               # there are still elements depending on us.
+               assert len(self.downstream_elements) == 0, "there are still downstream elements left"
+               
+               # disconnect all upstream elements from us
+               for upstream in self.upstream_elements:
+                       upstream.disconnectDownstream(self)
+       
+       def disconnectDownstream(self, downstream):
+               self.downstream_elements.remove(downstream)
+               if self.master == downstream:
+                       self.master = None
+               
+               if len(self.downstream_elements) == 0:
+                       self.disconnectAll()
+
        # default action: push downstream
        def changed(self):
                self.downstream_elements.changed()