- split of Components into different files

[vuplus_dvbapp] / lib / python / Components / GUISkin.py

diff --git a/lib/python/Components/GUISkin.py b/lib/python/Components/GUISkin.py
new file mode 100644 (file)
index 0000000..b918e90
--- /dev/null
+++ b/lib/python/Components/GUISkin.py
@@ -0,0 +1,65 @@
+from GUIComponent import *
+
+class GUISkin:
+       def __init__(self):
+               pass
+       
+       def createGUIScreen(self, parent):
+               for (name, val) in self.items():
+                       if isinstance(val, GUIComponent):
+                               val.GUIcreate(parent, None)
+       
+       def deleteGUIScreen(self):
+               for (name, val) in self.items():
+                       if isinstance(val, GUIComponent):
+                               val.GUIdelete()
+                       try:
+                               val.fix()
+                       except:
+                               pass
+                       
+                       # DIESER KOMMENTAR IST NUTZLOS UND MITTLERWEILE VERALTET! (glaub ich)
+                       # BITTE NICHT LESEN!
+                       # 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()
+