python/rox/Menu.py

   1 """The Menu widget provides an easy way to create menus that allow the user to
   2 define keyboard shortcuts, and saves the shortcuts automatically. You only define
   3 each Menu once, and attach it to windows as required.
   4
   5 Example:
   6
   7 from rox.Menu import Menu, set_save_name
   8
   9 set_save_name('Edit')
  10
  11 menu = Menu('main', [
  12         ('/File',               '',             '<Branch>'),
  13         ('/File/Save',          'save',         ''),
  14         ('/File/Open Parent',   'up',           ''),
  15         ('/File/Close',         'close',        ''),
  16         ('/File/',              '',             '<Separator>'),
  17         ('/File/New',           'new',          ''),
  18         ('/Edit',               '',             '<Branch>'),
  19         ('/Edit/Undo',          'undo',         ''),
  20         ('/Edit/Redo',          'redo',         ''),
  21         ('/Edit/',              '',             '<Separator>'),
  22         ('/Edit/Search...',     'search',       ''),
  23         ('/Edit/Goto line...',  'goto',         ''),
  24         ('/Edit/',              '',             '<Separator>'),
  25         ('/Edit/Process...',    'process',      ''),
  26         ('/Options',            'show_options', ''),
  27         ('/Help',               'help',         '<StockItem>',  'F1', g.STOCK_HELP),
  28         ])
  29 """
  30
  31 import rox
  32 from rox import g
  33 import choices
  34
  35 _save_name = None
  36 def set_save_name(prog, leaf = 'menus'):
  37         """Set the directory/leafname (see choices) used to save the menu keys.
  38         Call this before creating any menus."""
  39         global _save_name
  40         _save_name = (prog, leaf)
  41
  42 class Menu:
  43         def __init__(self, name, items):
  44                 """names should be unique (eg, 'popup', 'main', etc).
  45                 items is a list of menu items:
  46                 [(name, callback_name, type, key), ...].
  47                 'name' is the item's path.
  48                 'callback_name' is the NAME of a method to call.
  49                 'type' is as for g.ItemFactory.
  50                 'key' is only used if no bindings are in Choices."""
  51                 if not _save_name:
  52                         raise Exception('Call rox.Menu.set_save_name() first!')
  53
  54                 ag = g.AccelGroup()
  55                 self.accel_group = ag
  56                 factory = g.ItemFactory(g.Menu, '<%s>' % name, ag)
  57
  58                 program, save_leaf = _save_name
  59                 path = choices.load(program, save_leaf)
  60
  61                 out = []
  62                 self.fns = []
  63                 for item  in items:
  64                         stock = None
  65                         key = None
  66                         if len(item) == 3:
  67                                 (label, fn, type) = item
  68                         elif len(item) == 4:
  69                                 (label, fn, type, key) = item
  70                         else:
  71                                 (label, fn, type, key, stock) = item
  72                         if fn:
  73                                 self.fns.append(fn)
  74                                 cb = self._activate
  75                         else:
  76                                 cb = None
  77                         if stock:
  78                                 out.append((label, key, cb, len(self.fns) - 1, type, stock))
  79                         else:
  80                                 out.append((label, key, cb, len(self.fns) - 1, type))
  81
  82                 factory.create_items(out)
  83                 self.factory = factory
  84
  85                 if path:
  86                         g.accel_map_load(path)
  87
  88                 self.caller = None      # Caller of currently open menu
  89                 self.menu = factory.get_widget('<%s>' % name)
  90
  91                 def keys_changed(*unused):
  92                         program, name = _save_name
  93                         path = choices.save(program, name)
  94                         if path:
  95                                 try:
  96                                         g.accel_map_save(path)
  97                                 except AttributeError:
  98                                         print "Error saving keybindings to", path
  99                 ag.connect('accel_changed', keys_changed)
 100
 101         def attach(self, window, object):
 102                 """Keypresses on this window will be treated as menu shortcuts
 103                 for this object, calling 'object.<callback_name>' when used."""
 104                 def kev(w, k):
 105                         self.caller = object
 106                         return 0
 107                 window.connect('key-press-event', kev)
 108                 window.add_accel_group(self.accel_group)
 109
 110         def _position(self, menu):
 111                 x, y, mods = g.gdk.get_default_root_window().get_pointer()
 112                 width, height = menu.size_request()
 113                 return (x - width * 3 / 4, y - 16, True)
 114
 115         def popup(self, caller, event, position_fn = None):
 116                 """Display the menu. Call 'caller.<callback_name>' when an item is chosen.
 117                 For applets, position_fn should be my_applet.position_menu)."""
 118                 self.caller = caller
 119                 if event:
 120                         self.menu.popup(None, None, position_fn or self._position, event.button, event.time)
 121                 else:
 122                         self.menu.popup(None, None, position_fn or self._position, 0, 0)
 123
 124         def _activate(self, action, widget):
 125                 if self.caller:
 126                         try:
 127                                 getattr(self.caller, self.fns[action])()
 128                         except:
 129                                 rox.report_exception()
 130                 else:
 131                         raise Exception("No caller for menu!")