- fixed dvb scan
[enigma2.git] / components.py
index 8ae4806..8015621 100644 (file)
@@ -1,5 +1,6 @@
 from enigma import *
 import time
+import sys
 
 # some helper classes first:
 class HTMLComponent:
@@ -20,12 +21,72 @@ class HTMLSkin:
                return res
 
 class GUISkin:
-       data = { }
+       def __init__(self):
+               self.data = { }
+       
        def createGUIScreen(self, parent):
                for (name, val) in self.items():
                        self.data[name] = { }
                        val.GUIcreate(self.data[name], parent, None)
+       
+       def deleteGUIScreen(self):
+               for (name, val) in self.items():
+                       w = self.data[name]["instance"]
+                       val.GUIdelete(self.data[name])
+                       del self.data[name]
+                       
+                       # note: you'll probably run into this assert. if this happens, don't panic!
+                       # yes, it's evil. I told you that programming in python is just fun, and 
+                       # suddently, you have to care about things you don't even know.
+                       #
+                       # but calm down, the solution is easy, at least on paper:
+                       #
+                       # Each Component, which is a GUIComponent, owns references to each
+                       # instantiated eWidget (namely in screen.data[name]["instance"], in case
+                       # you care.)
+                       # on deleteGUIscreen, all eWidget *must* (!) be deleted (otherwise,
+                       # well, problems appear. I don't want to go into details too much,
+                       # but this would be a memory leak anyway.)
+                       # The assert beyond checks for that. It asserts that the corresponding
+                       # eWidget is about to be removed (i.e., that the refcount becomes 0 after
+                       # running deleteGUIscreen).
+                       # (You might wonder why the refcount is checked for 2 and not for 1 or 0 -
+                       # one reference is still hold by the local variable 'w', another one is
+                       # hold be the function argument to sys.getrefcount itself. So only if it's
+                       # 2 at this point, the object will be destroyed after leaving deleteGUIscreen.)
+                       #
+                       # Now, how to fix this problem? You're holding a reference somewhere. (References
+                       # can only be hold from Python, as eWidget itself isn't related to the c++
+                       # way of having refcounted objects. So it must be in python.)
+                       #
+                       # It could be possible that you're calling deleteGUIscreen trough a call of
+                       # a PSignal. For example, you could try to call screen.doClose() in response
+                       # to a Button::click. This will fail. (It wouldn't work anyway, as you would
+                       # remove a dialog while running it. It never worked - enigma1 just set a 
+                       # per-mainloop variable on eWidget::close() to leave the exec()...)
+                       # That's why Session supports delayed closes. Just call Session.close() and
+                       # it will work.
+                       #
+                       # Another reason is that you just stored the data["instance"] somewhere. or
+                       # added it into a notifier list and didn't removed it.
+                       #
+                       # If you can't help yourself, just ask me. I'll be glad to help you out.
+                       # Sorry for not keeping this code foolproof. I really wanted to archive
+                       # that, but here I failed miserably. All I could do was to add this assert.
+                       assert sys.getrefcount(w) == 2, "too many refs hold to " + str(w)
+       
+       def close(self):
+               self.deleteGUIScreen()
+               del self.data
+
+# note: components can be used in multiple screens, so we have kind of
+# two contexts: first the per-component one (self), then the per-screen (i.e.:
+# per eWidget one), called "priv". In "priv", for example, the instance
+# of the eWidget is stored.
 
+
+# GUI components have a "notifier list" of associated eWidgets to one component
+# (as said - one component instance can be used at multiple screens)
 class GUIComponent:
        """ GUI component """
 
@@ -36,8 +97,20 @@ class GUIComponent:
                i = self.GUIcreateInstance(self, parent, skindata)
                priv["instance"] = i
                self.notifier.append(i)
-               if self.notifierAdded:
+               try:
                        self.notifierAdded(i)
+               except:
+                       pass
+       
+       # GUIdelete must delete *all* references to the current component!
+       def GUIdelete(self, priv):
+               g = priv["instance"]
+               self.notifier.remove(g)
+               self.GUIdeleteInstance(g)
+               del priv["instance"]
+
+       def GUIdeleteInstance(self, priv):
+               pass
 
 class VariableText:
        """VariableText can be used for components which have a variable text, based on any widget with setText call"""
@@ -107,19 +180,11 @@ class Button(HTMLComponent, GUIComponent, VariableText):
                self.setText(text)
                self.onClick = [ ]
        
-       def clicked(self):
+       def push(self):
                for x in self.onClick:
                        x()
                return 0
-
-       def GUIcreate(self, priv, parent, skindata):
-               GUIComponent.GUIcreate(self, priv,parent, skindata)
-               priv["instance"].selected.get().append(self.clicked)
        
-       def click(self):
-               for x in self.onClick:
-                       x()
-
 # html:        
        def produceHTML(self):
                return "<input type=\"submit\" text=\"" + self.getText() + "\">\n"
@@ -127,8 +192,11 @@ class Button(HTMLComponent, GUIComponent, VariableText):
 # GUI:
        def GUIcreateInstance(self, priv, parent, skindata):
                g = eButton(parent)
-#              g.clicked = [ self.click ]
+               g.selected.get().append(self.push)
                return g
+       
+       def GUIdeleteInstance(self, g):
+               g.selected.get().remove(self.push)
 
 class Header(HTMLComponent, GUIComponent, VariableText):
 
@@ -156,3 +224,36 @@ class VolumeBar(HTMLComponent, GUIComponent, VariableValue):
                g.setRange(0, 100)
                return g
 
+
+class MenuList(HTMLComponent, GUIComponent):
+       def __init__(self, list):
+               GUIComponent.__init__(self)
+               self.l = eListboxPythonStringContent()
+               self.l.setList(list)
+       
+       def getCurrent(self):
+               return self.l.getCurrentSelection()
+       
+       def GUIcreateInstance(self, priv, parent, skindata):
+               g = eListbox(parent)
+               g.setContent(self.l)
+               return g
+       
+       def GUIdeleteInstance(self, g):
+               g.setContent(None)
+
+class ServiceList(HTMLComponent, GUIComponent):
+       def __init__(self):
+               GUIComponent.__init__(self)
+               self.l = eListboxServiceContent()
+
+       def GUIcreateInstance(self, priv, parent, skindata):
+               g = eListbox(parent)
+               g.setContent(self.l)
+               return g
+       
+       def GUIdeleteInstance(self, g):
+               g.setContent(None)
+
+       def setRoot(self, root):
+               self.l.setRoot(root)