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, Action, Separator, SubMenu
   8
   9 set_save_name('Edit')
  10
  11 menu = Menu('main', [
  12         SubMenu('File', Menu([
  13           Action('Save',                'save'),
  14           Action('Open Parent',         'up'),
  15           Action('Close',               'close'),
  16           Separator(),
  17           Action('New',                 'new')
  18         ])),
  19         SubMenu('/Edit', Menu([
  20           Action('Undo',                'undo'),
  21           Action('Redo',                'redo'),
  22           Separator(),
  23           Action('Search...',           'search'),
  24           Action('Goto line...',        'goto'),
  25           Separator(),
  26           Action('Process...',          'process'),
  27         ])),
  28         Action('Options',               'show_options'),
  29         Action('Quit',                  'show_options', 'F1', stock=g.STOCK_HELP),
  30         ])
  31
  32 There is also an older syntax, where you pass tuples of strings
  33 to the Menu constructor. This has not been required since 1.9.13.
  34 """
  35
  36 from __future__ import generators
  37
  38 import os
  39 import rox
  40 from rox import g
  41 import choices, basedir
  42
  43 import warnings
  44 warnings.filterwarnings('ignore', 'use gtk.UIManager', DeprecationWarning,
  45                         'rox')
  46
  47 _save_name = None
  48 def set_save_name(prog, leaf = 'menus', site = None):
  49         """Set the directory/leafname (see choices) used to save the menu keys.
  50         Call this before creating any menus.
  51         If 'site' is given, the basedir module is used for saving bindings (the
  52         new system). Otherwise, the deprecated choices module is used."""
  53         global _save_name
  54         _save_name = (site, prog, leaf)
  55
  56 class MenuItem:
  57         """Base class for menu items. You should normally use one of the subclasses..."""
  58         def __init__(self, label, callback_name, type = '', key = None, stock = None):
  59                 if label and label[0] == '/':
  60                         self.label = label[1:]
  61                 else:
  62                         self.label = label
  63                 self.fn = callback_name
  64                 self.type = type
  65                 self.key = key
  66                 self.stock = stock
  67
  68         def activate(self, caller):
  69                 getattr(caller, self.fn)()
  70
  71 class Action(MenuItem):
  72         """A leaf menu item, possibly with a stock icon, which calls a method when clicked."""
  73         def __init__(self, label, callback_name, key = None, stock = None, values = ()):
  74                 """object.callback(*values) is called when the item is activated."""
  75                 if stock:
  76                         MenuItem.__init__(self, label, callback_name, '<StockItem>', key, stock)
  77                 else:
  78                         MenuItem.__init__(self, label, callback_name, '', key)
  79                 self.values = values
  80
  81         def activate(self, caller):
  82                 getattr(caller, self.fn)(*self.values)
  83
  84 class ToggleItem(MenuItem):
  85         """A menu item that has a check icon and toggles state each time it is activated."""
  86         def __init__(self, label, property_name):
  87                 """property_name is a boolean property on the caller object. You can use
  88                 the built-in Python class property() if you want to perform calculations when
  89                 getting or setting the value."""
  90                 MenuItem.__init__(self, label, property_name, '<ToggleItem>')
  91                 self.updating = False
  92
  93         def update(self, menu, widget):
  94                 """Called when then menu is opened."""
  95                 self.updating = True
  96                 state = getattr(menu.caller, self.fn)
  97                 widget.set_active(state)
  98                 self.updating = False
  99
 100         def activate(self, caller):
 101                 if not self.updating:
 102                         setattr(caller, self.fn, not getattr(caller, self.fn))
 103
 104 class SubMenu(MenuItem):
 105         """A branch menu item leading to a submenu."""
 106         def __init__(self, label, submenu):
 107                 MenuItem.__init__(self, label, None, '<Branch>')
 108                 self.submenu = submenu
 109
 110 class Separator(MenuItem):
 111         """A line dividing two parts of the menu."""
 112         def __init__(self):
 113                 MenuItem.__init__(self, '', None, '<Separator>')
 114
 115 def _walk(items):
 116         for x in items:
 117                 yield "/" + x.label, x
 118                 if isinstance(x, SubMenu):
 119                         for l, y in _walk(x.submenu):
 120                                 yield "/" + x.label + l, y
 121
 122 class Menu:
 123         """A popup menu. This wraps GtkMenu. It handles setting, loading and saving of
 124         keyboard-shortcuts, applies translations, and has a simpler API."""
 125         fns = None              # List of MenuItem objects which can be activated
 126         update_callbacks = None # List of functions to call just before popping up the menu
 127         accel_group = None
 128         menu = None             # The actual GtkMenu
 129
 130         def __init__(self, name, items):
 131                 """names should be unique (eg, 'popup', 'main', etc).
 132                 items is a list of menu items:
 133                 [(name, callback_name, type, key), ...].
 134                 'name' is the item's path.
 135                 'callback_name' is the NAME of a method to call.
 136                 'type' is as for g.ItemFactory.
 137                 'key' is only used if no bindings are in Choices."""
 138                 if not _save_name:
 139                         raise Exception('Call rox.Menu.set_save_name() first!')
 140
 141                 ag = g.AccelGroup()
 142                 self.accel_group = ag
 143                 factory = g.ItemFactory(g.Menu, '<%s>' % name, ag)
 144
 145                 site, program, save_leaf = _save_name
 146                 if site:
 147                         accel_path = basedir.load_first_config(site, program, save_leaf)
 148                 else:
 149                         accel_path = choices.load(program, save_leaf)
 150
 151                 out = []
 152                 self.fns = []
 153
 154                 # Convert old-style list of tuples to new classes
 155                 if items and not isinstance(items[0], MenuItem):
 156                         items = [MenuItem(*t) for t in items]
 157
 158                 items_with_update = []
 159                 for path, item in _walk(items):
 160                         if item.fn:
 161                                 self.fns.append(item)
 162                                 cb = self._activate
 163                         else:
 164                                 cb = None
 165                         if item.stock:
 166                                 out.append((path, item.key, cb, len(self.fns) - 1, item.type, item.stock))
 167                         else:
 168                                 out.append((path, item.key, cb, len(self.fns) - 1, item.type))
 169                         if hasattr(item, 'update'):
 170                                 items_with_update.append((path, item))
 171
 172                 factory.create_items(out)
 173                 self.factory = factory
 174
 175                 self.update_callbacks = []
 176                 for path, item in items_with_update:
 177                         widget = factory.get_widget(path)
 178                         fn = item.update
 179                         self.update_callbacks.append(lambda f = fn, w = widget: f(self, w))
 180
 181                 if accel_path:
 182                         g.accel_map_load(accel_path)
 183
 184                 self.caller = None      # Caller of currently open menu
 185                 self.menu = factory.get_widget('<%s>' % name)
 186
 187                 def keys_changed(*unused):
 188                         site, program, name = _save_name
 189                         if site:
 190                                 d = basedir.save_config_path(site, program)
 191                                 path = os.path.join(d, name)
 192                         else:
 193                                 path = choices.save(program, name)
 194                         if path:
 195                                 try:
 196                                         g.accel_map_save(path)
 197                                 except AttributeError:
 198                                         print "Error saving keybindings to", path
 199                 # GtkAccelGroup has its own (unrelated) connect method,
 200                 # so the obvious approach doesn't work.
 201                 #ag.connect('accel_changed', keys_changed)
 202                 import gobject
 203                 gobject.GObject.connect(ag, 'accel_changed', keys_changed)
 204
 205         def attach(self, window, object):
 206                 """Keypresses on this window will be treated as menu shortcuts
 207                 for this object, calling 'object.<callback_name>' when used."""
 208                 def kev(w, k):
 209                         self.caller = object
 210                         return 0
 211                 window.connect('key-press-event', kev)
 212                 window.add_accel_group(self.accel_group)
 213
 214         def _position(self, menu):
 215                 x, y, mods = g.gdk.get_default_root_window().get_pointer()
 216                 width, height = menu.size_request()
 217                 return (x - width * 3 / 4, y - 16, True)
 218
 219         def popup(self, caller, event, position_fn = None):
 220                 """Display the menu. Call 'caller.<callback_name>' when an item is chosen.
 221                 For applets, position_fn should be my_applet.position_menu)."""
 222                 self.caller = caller
 223                 map(apply, self.update_callbacks) # Update toggles, etc
 224                 if event:
 225                         self.menu.popup(None, None, position_fn or self._position, event.button, event.time)
 226                 else:
 227                         self.menu.popup(None, None, position_fn or self._position, 0, 0)
 228
 229         def _activate(self, action, widget):
 230                 if self.caller:
 231                         try:
 232                                 self.fns[action].activate(self.caller)
 233                         except:
 234                                 rox.report_exception()
 235                 else:
 236                         raise Exception("No caller for menu!")