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.onFirstExecBegin = [ ]
  18                 self.onExecBegin = [ ]
  19                 self.onShown = [ ]
  20
  21                 self.onShow = [ ]
  22                 self.onHide = [ ]
  23
  24                 self.execing = False
  25                 self.shown = True
  26
  27                 self.renderer = [ ]
  28
  29                 # in order to support screens *without* a help,
  30                 # we need the list in every screen. how ironic.
  31                 self.helpList = [ ]
  32
  33                 self.close_on_next_exec = None
  34
  35                 # stand alone screens (for example web screens)
  36                 # don't care about having or not having focus.
  37                 self.stand_alone = False
  38
  39         def execBegin(self):
  40                 self.active_components = [ ]
  41                 if self.close_on_next_exec is not None:
  42                         tmp = self.close_on_next_exec
  43                         self.close_on_next_exec = None
  44                         self.execing = True
  45                         self.close(tmp)
  46                 else:
  47                         single = self.onFirstExecBegin
  48                         self.onFirstExecBegin = []
  49                         for x in self.onExecBegin + single:
  50                                 x()
  51                                 if not self.stand_alone and self.session.current_dialog != self:
  52                                         return
  53
  54 #                       assert self.session == None, "a screen can only exec once per time"
  55 #                       self.session = session
  56
  57                         for val in self.values() + self.renderer:
  58                                 val.execBegin()
  59                                 if not self.stand_alone and self.session.current_dialog != self:
  60                                         return
  61                                 self.active_components.append(val)
  62
  63                         self.execing = True
  64
  65                         for x in self.onShown:
  66                                 x()
  67
  68         def execEnd(self):
  69 #               for (name, val) in self.items():
  70                 for val in self.active_components:
  71                         val.execEnd()
  72                 del self.active_components
  73 #               assert self.session != None, "execEnd on non-execing screen!"
  74 #               self.session = None
  75                 self.execing = False
  76
  77         # never call this directly - it will be called from the session!
  78         def doClose(self):
  79                 self.hide()
  80                 for x in self.onClose:
  81                         x()
  82
  83                 # fixup circular references
  84                 del self.helpList
  85                 GUISkin.close(self)
  86
  87                 # first disconnect all render from their sources.
  88                 # we might split this out into a "unskin"-call,
  89                 # but currently we destroy the screen afterwards
  90                 # anyway.
  91                 for val in self.renderer:
  92                         val.disconnectAll()  # disconnected converter/sources and probably destroy them
  93
  94                 del self.session
  95                 for (name, val) in self.items():
  96                         val.destroy()
  97                         del self[name]
  98
  99                 for val in self.renderer:
 100                         val.destroy()
 101
 102                 self.renderer = [ ]
 103
 104                 # really delete all elements now
 105                 self.__dict__.clear()
 106
 107         def close(self, *retval):
 108                 if not self.execing:
 109                         self.close_on_next_exec = retval
 110                 else:
 111                         self.session.close(self, *retval)
 112
 113         def setFocus(self, o):
 114                 self.instance.setFocus(o.instance)
 115
 116         def show(self, force = False):
 117                 if (self.shown and not force) or not self.instance:
 118                         return
 119                 self.shown = True
 120                 self.instance.show()
 121                 for x in self.onShow:
 122                         x()
 123                 for val in self.values() + self.renderer:
 124                         if isinstance(val, GUIComponent) or isinstance(val, Source):
 125                                 val.onShow()
 126
 127         def hide(self):
 128                 if not self.shown or not self.instance:
 129                         return
 130                 self.shown = False
 131                 self.instance.hide()
 132                 for x in self.onHide:
 133                         x()
 134                 for val in self.values() + self.renderer:
 135                         if isinstance(val, GUIComponent) or isinstance(val, Source):
 136                                 val.onHide()
 137
 138         def __repr__(self):
 139                 return str(type(self))