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