lib/python/Screens/Screen.py

   1 from Components.HTMLSkin import *
   2 from Components.GUISkin import *
   3 from Components.Sources.Source import Source
   4
   5 import sys
   6
   7 class Screen(dict, HTMLSkin, GUISkin):
   8
   9         ALLOW_SUSPEND = False
  10
  11         def __init__(self, session):
  12                 self.skinName = self.__class__.__name__
  13                 self.session = session
  14                 GUISkin.__init__(self)
  15
  16                 self.onClose = [ ]
  17                 self.onExecBegin = [ ]
  18                 self.onShown = [ ]
  19
  20                 self.onShow = [ ]
  21                 self.onHide = [ ]
  22
  23                 self.execing = False
  24                 self.shown = False
  25
  26                 # in order to support screens *without* a help,
  27                 # we need the list in every screen. how ironic.
  28                 self.helpList = [ ]
  29
  30         def execBegin(self):
  31                 self.active_components = [ ]
  32                 for x in self.onExecBegin:
  33                         x()
  34                         if self.session.current_dialog != self:
  35                                 return
  36
  37 #               assert self.session == None, "a screen can only exec once per time"
  38 #               self.session = session
  39
  40                 for val in self.values() + self.renderer:
  41                         val.execBegin()
  42                         if self.session.current_dialog != self:
  43                                 return
  44                         self.active_components.append(val)
  45
  46                 self.execing = True
  47
  48                 for x in self.onShown:
  49                         x()
  50
  51         def execEnd(self):
  52 #               for (name, val) in self.items():
  53                 for val in self.active_components:
  54                         val.execEnd()
  55                 del self.active_components
  56 #               assert self.session != None, "execEnd on non-execing screen!"
  57 #               self.session = None
  58                 self.execing = False
  59
  60         # never call this directly - it will be called from the session!
  61         def doClose(self):
  62                 self.hide()
  63                 for x in self.onClose:
  64                         x()
  65
  66                 # fixup circular references
  67                 del self.helpList
  68                 GUISkin.close(self)
  69
  70                 # first disconnect all render from their sources.
  71                 # we might split this out into a "unskin"-call,
  72                 # but currently we destroy the screen afterwards
  73                 # anyway.
  74                 for val in self.renderer:
  75                         val.disconnectAll()  # disconnected converter/sources and probably destroy them
  76
  77                 del self.session
  78                 for (name, val) in self.items():
  79                         val.destroy()
  80                         del self[name]
  81
  82                 for val in self.renderer:
  83                         val.destroy()
  84
  85                 self.renderer = [ ]
  86
  87                 # really delete all elements now
  88                 self.__dict__.clear()
  89
  90         def close(self, *retval):
  91                 self.session.close(self, *retval)
  92
  93         def setFocus(self, o):
  94                 self.instance.setFocus(o.instance)
  95
  96         def show(self):
  97                 if self.shown:
  98                         return
  99                 self.shown = True
 100                 self.instance.show()
 101                 for x in self.onShow:
 102                         x()
 103                 for val in self.values() + self.renderer:
 104                         if isinstance(val, GUIComponent) or isinstance(val, Source):
 105                                 val.onShow()
 106
 107         def hide(self):
 108                 if not self.shown:
 109                         return
 110                 self.shown = False
 111                 self.instance.hide()
 112                 for x in self.onHide:
 113                         x()
 114                 for val in self.values() + self.renderer:
 115                         if isinstance(val, GUIComponent) or isinstance(val, Source):
 116                                 val.onHide()
 117
 118         def __repr__(self):
 119                 return str(type(self))