components.py

   1 from enigma import *
   2 import time
   3 import sys
   4
   5 # some helper classes first:
   6 class HTMLComponent:
   7         def produceHTML(self):
   8                 return ""
   9
  10 class HTMLSkin:
  11         order = ()
  12
  13         def __init__(self, order):
  14                 self.order = order
  15
  16         def produceHTML(self):
  17                 res = "<html>\n"
  18                 for name in self.order:
  19                         res += self[name].produceHTML()
  20                 res += "</html>\n";
  21                 return res
  22
  23 class GUISkin:
  24         def __init__(self):
  25                 self.data = { }
  26
  27         def createGUIScreen(self, parent):
  28                 for (name, val) in self.items():
  29                         self.data[name] = { }
  30                         val.GUIcreate(self.data[name], parent, None)
  31
  32         def deleteGUIScreen(self):
  33                 for (name, val) in self.items():
  34                         w = self.data[name]["instance"]
  35                         val.GUIdelete(self.data[name])
  36                         del self.data[name]
  37
  38                         # note: you'll probably run into this assert. if this happens, don't panic!
  39                         # yes, it's evil. I told you that programming in python is just fun, and
  40                         # suddently, you have to care about things you don't even know.
  41                         #
  42                         # but calm down, the solution is easy, at least on paper:
  43                         #
  44                         # Each Component, which is a GUIComponent, owns references to each
  45                         # instantiated eWidget (namely in screen.data[name]["instance"], in case
  46                         # you care.)
  47                         # on deleteGUIscreen, all eWidget *must* (!) be deleted (otherwise,
  48                         # well, problems appear. I don't want to go into details too much,
  49                         # but this would be a memory leak anyway.)
  50                         # The assert beyond checks for that. It asserts that the corresponding
  51                         # eWidget is about to be removed (i.e., that the refcount becomes 0 after
  52                         # running deleteGUIscreen).
  53                         # (You might wonder why the refcount is checked for 2 and not for 1 or 0 -
  54                         # one reference is still hold by the local variable 'w', another one is
  55                         # hold be the function argument to sys.getrefcount itself. So only if it's
  56                         # 2 at this point, the object will be destroyed after leaving deleteGUIscreen.)
  57                         #
  58                         # Now, how to fix this problem? You're holding a reference somewhere. (References
  59                         # can only be hold from Python, as eWidget itself isn't related to the c++
  60                         # way of having refcounted objects. So it must be in python.)
  61                         #
  62                         # It could be possible that you're calling deleteGUIscreen trough a call of
  63                         # a PSignal. For example, you could try to call screen.doClose() in response
  64                         # to a Button::click. This will fail. (It wouldn't work anyway, as you would
  65                         # remove a dialog while running it. It never worked - enigma1 just set a
  66                         # per-mainloop variable on eWidget::close() to leave the exec()...)
  67                         # That's why Session supports delayed closes. Just call Session.close() and
  68                         # it will work.
  69                         #
  70                         # Another reason is that you just stored the data["instance"] somewhere. or
  71                         # added it into a notifier list and didn't removed it.
  72                         #
  73                         # If you can't help yourself, just ask me. I'll be glad to help you out.
  74                         # Sorry for not keeping this code foolproof. I really wanted to archive
  75                         # that, but here I failed miserably. All I could do was to add this assert.
  76                         assert sys.getrefcount(w) == 2, "too many refs hold to " + str(w)
  77
  78         def close(self):
  79                 self.deleteGUIScreen()
  80                 del self.data
  81
  82 # note: components can be used in multiple screens, so we have kind of
  83 # two contexts: first the per-component one (self), then the per-screen (i.e.:
  84 # per eWidget one), called "priv". In "priv", for example, the instance
  85 # of the eWidget is stored.
  86
  87
  88 # GUI components have a "notifier list" of associated eWidgets to one component
  89 # (as said - one component instance can be used at multiple screens)
  90 class GUIComponent:
  91         """ GUI component """
  92
  93         def __init__(self):
  94                 self.notifier = [ ]
  95
  96         def GUIcreate(self, priv, parent, skindata):
  97                 i = self.GUIcreateInstance(self, parent, skindata)
  98                 priv["instance"] = i
  99                 self.notifier.append(i)
 100                 try:
 101                         self.notifierAdded(i)
 102                 except:
 103                         pass
 104
 105         # GUIdelete must delete *all* references to the current component!
 106         def GUIdelete(self, priv):
 107                 g = priv["instance"]
 108                 self.notifier.remove(g)
 109                 self.GUIdeleteInstance(g)
 110                 del priv["instance"]
 111
 112         def GUIdeleteInstance(self, priv):
 113                 pass
 114
 115 class VariableText:
 116         """VariableText can be used for components which have a variable text, based on any widget with setText call"""
 117
 118         def __init__(self):
 119                 self.message = ""
 120
 121         def notifierAdded(self, notifier):
 122                 notifier.setText(self.message)
 123
 124         def setText(self, text):
 125                 if self.message != text:
 126                         self.message = text
 127                         for x in self.notifier:
 128                                 x.setText(self.message)
 129
 130         def getText(self):
 131                 return self.message
 132
 133 class VariableValue:
 134         """VariableValue can be used for components which have a variable value (like eSlider), based on any widget with setValue call"""
 135
 136         def __init__(self):
 137                 self.value = 0
 138
 139         def notifierAdded(self, notifier):
 140                 notifier.setValue(self.value)
 141
 142         def setValue(self, value):
 143                 if self.value != value:
 144                         self.value = value
 145                         for x in self.notifier:
 146                                 x.setValue(self.value)
 147
 148         def getValue(self):
 149                 return self.value
 150
 151 # now some "real" components:
 152
 153 class Clock(HTMLComponent, GUIComponent, VariableText):
 154         def __init__(self):
 155                 VariableText.__init__(self)
 156                 GUIComponent.__init__(self)
 157                 self.doClock()
 158
 159                 self.clockTimer = eTimer()
 160                 self.clockTimer.timeout.get().append(self.doClock)
 161                 self.clockTimer.start(1000)
 162
 163 # "funktionalitaet"
 164         def doClock(self):
 165                 self.setText("clock: " + time.asctime())
 166
 167 # realisierung als GUI
 168         def GUIcreateInstance(self, priv, parent, skindata):
 169                 g = eLabel(parent)
 170                 return g
 171
 172 # ...und als HTML:
 173         def produceHTML(self):
 174                 return self.getText()
 175
 176 class Button(HTMLComponent, GUIComponent, VariableText):
 177         def __init__(self, text=""):
 178                 GUIComponent.__init__(self)
 179                 VariableText.__init__(self)
 180                 self.setText(text)
 181                 self.onClick = [ ]
 182
 183         def push(self):
 184                 for x in self.onClick:
 185                         x()
 186                 return 0
 187
 188 # html:
 189         def produceHTML(self):
 190                 return "<input type=\"submit\" text=\"" + self.getText() + "\">\n"
 191
 192 # GUI:
 193         def GUIcreateInstance(self, priv, parent, skindata):
 194                 g = eButton(parent)
 195                 g.selected.get().append(self.push)
 196                 return g
 197
 198         def GUIdeleteInstance(self, g):
 199                 g.selected.get().remove(self.push)
 200
 201 class Header(HTMLComponent, GUIComponent, VariableText):
 202
 203         def __init__(self, message):
 204                 GUIComponent.__init__(self)
 205                 VariableText.__init__(self)
 206                 self.setText(message)
 207
 208         def produceHTML(self):
 209                 return "<h2>" + self.getText() + "</h2>\n"
 210
 211         def GUIcreateInstance(self, priv, parent, skindata):
 212                 g = eLabel(parent)
 213                 g.setText(self.message)
 214                 return g
 215
 216 class VolumeBar(HTMLComponent, GUIComponent, VariableValue):
 217
 218         def __init__(self):
 219                 GUIComponent.__init__(self)
 220                 VariableValue.__init__(self)
 221
 222         def GUIcreateInstance(self, priv, parent, skindata):
 223                 g = eSlider(parent)
 224                 g.setRange(0, 100)
 225                 return g
 226
 227
 228 class MenuList(HTMLComponent, GUIComponent):
 229         def __init__(self, list):
 230                 GUIComponent.__init__(self)
 231                 self.l = eListboxPythonStringContent()
 232                 self.l.setList(list)
 233
 234         def getCurrent(self):
 235                 return self.l.getCurrentSelection()
 236
 237         def GUIcreateInstance(self, priv, parent, skindata):
 238                 g = eListbox(parent)
 239                 g.setContent(self.l)
 240                 return g
 241
 242         def GUIdeleteInstance(self, g):
 243                 g.setContent(None)
 244
 245 class ServiceList(HTMLComponent, GUIComponent):
 246         def __init__(self):
 247                 GUIComponent.__init__(self)
 248                 self.l = eListboxServiceContent()
 249
 250         def GUIcreateInstance(self, priv, parent, skindata):
 251                 g = eListbox(parent)
 252                 g.setContent(self.l)
 253                 return g
 254
 255         def GUIdeleteInstance(self, g):
 256                 g.setContent(None)
 257
 258         def setRoot(self, root):
 259                 self.l.setRoot(root)