lib/python/Screens/Screen.py

   1 from Tools.Profile import profile
   2
   3 profile("LOAD:GUISkin")
   4 from Components.GUISkin import GUISkin
   5 profile("LOAD:Source")
   6 from Components.Sources.Source import Source
   7 profile("LOAD:GUIComponent")
   8 from Components.GUIComponent import GUIComponent
   9
  10 class Screen(dict, GUISkin):
  11
  12         ALLOW_SUSPEND = False
  13
  14         global_screen = None
  15
  16         def __init__(self, session, parent = None):
  17                 self.skinName = self.__class__.__name__
  18                 self.session = session
  19                 self.parent = parent
  20                 GUISkin.__init__(self)
  21
  22                 self.onClose = [ ]
  23                 self.onFirstExecBegin = [ ]
  24                 self.onExecBegin = [ ]
  25                 self.onShown = [ ]
  26
  27                 self.onShow = [ ]
  28                 self.onHide = [ ]
  29
  30                 self.execing = False
  31
  32                 self.shown = True
  33                 # already shown is false until the screen is really shown (after creation)
  34                 self.already_shown = False
  35
  36                 self.renderer = [ ]
  37
  38                 # in order to support screens *without* a help,
  39                 # we need the list in every screen. how ironic.
  40                 self.helpList = [ ]
  41
  42                 self.close_on_next_exec = None
  43
  44                 # stand alone screens (for example web screens)
  45                 # don't care about having or not having focus.
  46                 self.stand_alone = False
  47
  48         def execBegin(self):
  49                 self.active_components = [ ]
  50                 if self.close_on_next_exec is not None:
  51                         tmp = self.close_on_next_exec
  52                         self.close_on_next_exec = None
  53                         self.execing = True
  54                         self.close(*tmp)
  55                 else:
  56                         single = self.onFirstExecBegin
  57                         self.onFirstExecBegin = []
  58                         for x in self.onExecBegin + single:
  59                                 x()
  60                                 if not self.stand_alone and self.session.current_dialog != self:
  61                                         return
  62
  63 #                       assert self.session == None, "a screen can only exec once per time"
  64 #                       self.session = session
  65
  66                         for val in self.values() + self.renderer:
  67                                 val.execBegin()
  68                                 if not self.stand_alone and self.session.current_dialog != self:
  69                                         return
  70                                 self.active_components.append(val)
  71
  72                         self.execing = True
  73
  74                         for x in self.onShown:
  75                                 x()
  76
  77         def execEnd(self):
  78                 active_components = self.active_components
  79 #               for (name, val) in self.items():
  80                 self.active_components = None
  81                 for val in active_components:
  82                         val.execEnd()
  83 #               assert self.session != None, "execEnd on non-execing screen!"
  84 #               self.session = None
  85                 self.execing = False
  86
  87         # never call this directly - it will be called from the session!
  88         def doClose(self):
  89                 self.hide()
  90                 for x in self.onClose:
  91                         x()
  92
  93                 # fixup circular references
  94                 del self.helpList
  95                 GUISkin.close(self)
  96
  97                 # first disconnect all render from their sources.
  98                 # we might split this out into a "unskin"-call,
  99                 # but currently we destroy the screen afterwards
 100                 # anyway.
 101                 for val in self.renderer:
 102                         val.disconnectAll()  # disconnected converter/sources and probably destroy them. Sources will not be destroyed.
 103
 104                 del self.session
 105                 for (name, val) in self.items():
 106                         val.destroy()
 107                         del self[name]
 108
 109                 self.renderer = [ ]
 110
 111                 # really delete all elements now
 112                 self.__dict__.clear()
 113
 114         def close(self, *retval):
 115                 if not self.execing:
 116                         self.close_on_next_exec = retval
 117                 else:
 118                         self.session.close(self, *retval)
 119
 120         def setFocus(self, o):
 121                 self.instance.setFocus(o.instance)
 122
 123         def show(self):
 124                 if (self.shown and self.already_shown) or not self.instance:
 125                         return
 126                 self.shown = True
 127                 self.already_shown = True
 128                 self.instance.show()
 129                 for x in self.onShow:
 130                         x()
 131                 for val in self.values() + self.renderer:
 132                         if isinstance(val, GUIComponent) or isinstance(val, Source):
 133                                 val.onShow()
 134
 135         def hide(self):
 136                 if not self.shown or not self.instance:
 137                         return
 138                 self.shown = False
 139                 self.instance.hide()
 140                 for x in self.onHide:
 141                         x()
 142                 for val in self.values() + self.renderer:
 143                         if isinstance(val, GUIComponent) or isinstance(val, Source):
 144                                 val.onHide()
 145
 146         def __repr__(self):
 147                 return str(type(self))
 148
 149         def getRelatedScreen(self, name):
 150                 if name == "session":
 151                         return self.session.screen
 152                 elif name == "parent":
 153                         return self.parent
 154                 elif name == "global":
 155                         return self.global_screen
 156                 else:
 157                         return None