jpayne@69: """
jpayne@69: MultiCall - a class which inherits its methods from a Tkinter widget (Text, for
jpayne@69: example), but enables multiple calls of functions per virtual event - all
jpayne@69: matching events will be called, not only the most specific one. This is done
jpayne@69: by wrapping the event functions - event_add, event_delete and event_info.
jpayne@69: MultiCall recognizes only a subset of legal event sequences. Sequences which
jpayne@69: are not recognized are treated by the original Tk handling mechanism. A
jpayne@69: more-specific event will be called before a less-specific event.
jpayne@69: 
jpayne@69: The recognized sequences are complete one-event sequences (no emacs-style
jpayne@69: Ctrl-X Ctrl-C, no shortcuts like <3>), for all types of events.
jpayne@69: Key/Button Press/Release events can have modifiers.
jpayne@69: The recognized modifiers are Shift, Control, Option and Command for Mac, and
jpayne@69: Control, Alt, Shift, Meta/M for other platforms.
jpayne@69: 
jpayne@69: For all events which were handled by MultiCall, a new member is added to the
jpayne@69: event instance passed to the binded functions - mc_type. This is one of the
jpayne@69: event type constants defined in this module (such as MC_KEYPRESS).
jpayne@69: For Key/Button events (which are handled by MultiCall and may receive
jpayne@69: modifiers), another member is added - mc_state. This member gives the state
jpayne@69: of the recognized modifiers, as a combination of the modifier constants
jpayne@69: also defined in this module (for example, MC_SHIFT).
jpayne@69: Using these members is absolutely portable.
jpayne@69: 
jpayne@69: The order by which events are called is defined by these rules:
jpayne@69: 1. A more-specific event will be called before a less-specific event.
jpayne@69: 2. A recently-binded event will be called before a previously-binded event,
jpayne@69:    unless this conflicts with the first rule.
jpayne@69: Each function will be called at most once for each event.
jpayne@69: """
jpayne@69: import re
jpayne@69: import sys
jpayne@69: 
jpayne@69: import tkinter
jpayne@69: 
jpayne@69: # the event type constants, which define the meaning of mc_type
jpayne@69: MC_KEYPRESS=0; MC_KEYRELEASE=1; MC_BUTTONPRESS=2; MC_BUTTONRELEASE=3;
jpayne@69: MC_ACTIVATE=4; MC_CIRCULATE=5; MC_COLORMAP=6; MC_CONFIGURE=7;
jpayne@69: MC_DEACTIVATE=8; MC_DESTROY=9; MC_ENTER=10; MC_EXPOSE=11; MC_FOCUSIN=12;
jpayne@69: MC_FOCUSOUT=13; MC_GRAVITY=14; MC_LEAVE=15; MC_MAP=16; MC_MOTION=17;
jpayne@69: MC_MOUSEWHEEL=18; MC_PROPERTY=19; MC_REPARENT=20; MC_UNMAP=21; MC_VISIBILITY=22;
jpayne@69: # the modifier state constants, which define the meaning of mc_state
jpayne@69: MC_SHIFT = 1<<0; MC_CONTROL = 1<<2; MC_ALT = 1<<3; MC_META = 1<<5
jpayne@69: MC_OPTION = 1<<6; MC_COMMAND = 1<<7
jpayne@69: 
jpayne@69: # define the list of modifiers, to be used in complex event types.
jpayne@69: if sys.platform == "darwin":
jpayne@69:     _modifiers = (("Shift",), ("Control",), ("Option",), ("Command",))
jpayne@69:     _modifier_masks = (MC_SHIFT, MC_CONTROL, MC_OPTION, MC_COMMAND)
jpayne@69: else:
jpayne@69:     _modifiers = (("Control",), ("Alt",), ("Shift",), ("Meta", "M"))
jpayne@69:     _modifier_masks = (MC_CONTROL, MC_ALT, MC_SHIFT, MC_META)
jpayne@69: 
jpayne@69: # a dictionary to map a modifier name into its number
jpayne@69: _modifier_names = dict([(name, number)
jpayne@69:                          for number in range(len(_modifiers))
jpayne@69:                          for name in _modifiers[number]])
jpayne@69: 
jpayne@69: # In 3.4, if no shell window is ever open, the underlying Tk widget is
jpayne@69: # destroyed before .__del__ methods here are called.  The following
jpayne@69: # is used to selectively ignore shutdown exceptions to avoid
jpayne@69: # 'Exception ignored' messages.  See http://bugs.python.org/issue20167
jpayne@69: APPLICATION_GONE = "application has been destroyed"
jpayne@69: 
jpayne@69: # A binder is a class which binds functions to one type of event. It has two
jpayne@69: # methods: bind and unbind, which get a function and a parsed sequence, as
jpayne@69: # returned by _parse_sequence(). There are two types of binders:
jpayne@69: # _SimpleBinder handles event types with no modifiers and no detail.
jpayne@69: # No Python functions are called when no events are binded.
jpayne@69: # _ComplexBinder handles event types with modifiers and a detail.
jpayne@69: # A Python function is called each time an event is generated.
jpayne@69: 
jpayne@69: class _SimpleBinder:
jpayne@69:     def __init__(self, type, widget, widgetinst):
jpayne@69:         self.type = type
jpayne@69:         self.sequence = '<'+_types[type][0]+'>'
jpayne@69:         self.widget = widget
jpayne@69:         self.widgetinst = widgetinst
jpayne@69:         self.bindedfuncs = []
jpayne@69:         self.handlerid = None
jpayne@69: 
jpayne@69:     def bind(self, triplet, func):
jpayne@69:         if not self.handlerid:
jpayne@69:             def handler(event, l = self.bindedfuncs, mc_type = self.type):
jpayne@69:                 event.mc_type = mc_type
jpayne@69:                 wascalled = {}
jpayne@69:                 for i in range(len(l)-1, -1, -1):
jpayne@69:                     func = l[i]
jpayne@69:                     if func not in wascalled:
jpayne@69:                         wascalled[func] = True
jpayne@69:                         r = func(event)
jpayne@69:                         if r:
jpayne@69:                             return r
jpayne@69:             self.handlerid = self.widget.bind(self.widgetinst,
jpayne@69:                                               self.sequence, handler)
jpayne@69:         self.bindedfuncs.append(func)
jpayne@69: 
jpayne@69:     def unbind(self, triplet, func):
jpayne@69:         self.bindedfuncs.remove(func)
jpayne@69:         if not self.bindedfuncs:
jpayne@69:             self.widget.unbind(self.widgetinst, self.sequence, self.handlerid)
jpayne@69:             self.handlerid = None
jpayne@69: 
jpayne@69:     def __del__(self):
jpayne@69:         if self.handlerid:
jpayne@69:             try:
jpayne@69:                 self.widget.unbind(self.widgetinst, self.sequence,
jpayne@69:                         self.handlerid)
jpayne@69:             except tkinter.TclError as e:
jpayne@69:                 if not APPLICATION_GONE in e.args[0]:
jpayne@69:                     raise
jpayne@69: 
jpayne@69: # An int in range(1 << len(_modifiers)) represents a combination of modifiers
jpayne@69: # (if the least significant bit is on, _modifiers[0] is on, and so on).
jpayne@69: # _state_subsets gives for each combination of modifiers, or *state*,
jpayne@69: # a list of the states which are a subset of it. This list is ordered by the
jpayne@69: # number of modifiers is the state - the most specific state comes first.
jpayne@69: _states = range(1 << len(_modifiers))
jpayne@69: _state_names = [''.join(m[0]+'-'
jpayne@69:                         for i, m in enumerate(_modifiers)
jpayne@69:                         if (1 << i) & s)
jpayne@69:                 for s in _states]
jpayne@69: 
jpayne@69: def expand_substates(states):
jpayne@69:     '''For each item of states return a list containing all combinations of
jpayne@69:     that item with individual bits reset, sorted by the number of set bits.
jpayne@69:     '''
jpayne@69:     def nbits(n):
jpayne@69:         "number of bits set in n base 2"
jpayne@69:         nb = 0
jpayne@69:         while n:
jpayne@69:             n, rem = divmod(n, 2)
jpayne@69:             nb += rem
jpayne@69:         return nb
jpayne@69:     statelist = []
jpayne@69:     for state in states:
jpayne@69:         substates = list(set(state & x for x in states))
jpayne@69:         substates.sort(key=nbits, reverse=True)
jpayne@69:         statelist.append(substates)
jpayne@69:     return statelist
jpayne@69: 
jpayne@69: _state_subsets = expand_substates(_states)
jpayne@69: 
jpayne@69: # _state_codes gives for each state, the portable code to be passed as mc_state
jpayne@69: _state_codes = []
jpayne@69: for s in _states:
jpayne@69:     r = 0
jpayne@69:     for i in range(len(_modifiers)):
jpayne@69:         if (1 << i) & s:
jpayne@69:             r |= _modifier_masks[i]
jpayne@69:     _state_codes.append(r)
jpayne@69: 
jpayne@69: class _ComplexBinder:
jpayne@69:     # This class binds many functions, and only unbinds them when it is deleted.
jpayne@69:     # self.handlerids is the list of seqs and ids of binded handler functions.
jpayne@69:     # The binded functions sit in a dictionary of lists of lists, which maps
jpayne@69:     # a detail (or None) and a state into a list of functions.
jpayne@69:     # When a new detail is discovered, handlers for all the possible states
jpayne@69:     # are binded.
jpayne@69: 
jpayne@69:     def __create_handler(self, lists, mc_type, mc_state):
jpayne@69:         def handler(event, lists = lists,
jpayne@69:                     mc_type = mc_type, mc_state = mc_state,
jpayne@69:                     ishandlerrunning = self.ishandlerrunning,
jpayne@69:                     doafterhandler = self.doafterhandler):
jpayne@69:             ishandlerrunning[:] = [True]
jpayne@69:             event.mc_type = mc_type
jpayne@69:             event.mc_state = mc_state
jpayne@69:             wascalled = {}
jpayne@69:             r = None
jpayne@69:             for l in lists:
jpayne@69:                 for i in range(len(l)-1, -1, -1):
jpayne@69:                     func = l[i]
jpayne@69:                     if func not in wascalled:
jpayne@69:                         wascalled[func] = True
jpayne@69:                         r = l[i](event)
jpayne@69:                         if r:
jpayne@69:                             break
jpayne@69:                 if r:
jpayne@69:                     break
jpayne@69:             ishandlerrunning[:] = []
jpayne@69:             # Call all functions in doafterhandler and remove them from list
jpayne@69:             for f in doafterhandler:
jpayne@69:                 f()
jpayne@69:             doafterhandler[:] = []
jpayne@69:             if r:
jpayne@69:                 return r
jpayne@69:         return handler
jpayne@69: 
jpayne@69:     def __init__(self, type, widget, widgetinst):
jpayne@69:         self.type = type
jpayne@69:         self.typename = _types[type][0]
jpayne@69:         self.widget = widget
jpayne@69:         self.widgetinst = widgetinst
jpayne@69:         self.bindedfuncs = {None: [[] for s in _states]}
jpayne@69:         self.handlerids = []
jpayne@69:         # we don't want to change the lists of functions while a handler is
jpayne@69:         # running - it will mess up the loop and anyway, we usually want the
jpayne@69:         # change to happen from the next event. So we have a list of functions
jpayne@69:         # for the handler to run after it finishes calling the binded functions.
jpayne@69:         # It calls them only once.
jpayne@69:         # ishandlerrunning is a list. An empty one means no, otherwise - yes.
jpayne@69:         # this is done so that it would be mutable.
jpayne@69:         self.ishandlerrunning = []
jpayne@69:         self.doafterhandler = []
jpayne@69:         for s in _states:
jpayne@69:             lists = [self.bindedfuncs[None][i] for i in _state_subsets[s]]
jpayne@69:             handler = self.__create_handler(lists, type, _state_codes[s])
jpayne@69:             seq = '<'+_state_names[s]+self.typename+'>'
jpayne@69:             self.handlerids.append((seq, self.widget.bind(self.widgetinst,
jpayne@69:                                                           seq, handler)))
jpayne@69: 
jpayne@69:     def bind(self, triplet, func):
jpayne@69:         if triplet[2] not in self.bindedfuncs:
jpayne@69:             self.bindedfuncs[triplet[2]] = [[] for s in _states]
jpayne@69:             for s in _states:
jpayne@69:                 lists = [ self.bindedfuncs[detail][i]
jpayne@69:                           for detail in (triplet[2], None)
jpayne@69:                           for i in _state_subsets[s]       ]
jpayne@69:                 handler = self.__create_handler(lists, self.type,
jpayne@69:                                                 _state_codes[s])
jpayne@69:                 seq = "<%s%s-%s>"% (_state_names[s], self.typename, triplet[2])
jpayne@69:                 self.handlerids.append((seq, self.widget.bind(self.widgetinst,
jpayne@69:                                                               seq, handler)))
jpayne@69:         doit = lambda: self.bindedfuncs[triplet[2]][triplet[0]].append(func)
jpayne@69:         if not self.ishandlerrunning:
jpayne@69:             doit()
jpayne@69:         else:
jpayne@69:             self.doafterhandler.append(doit)
jpayne@69: 
jpayne@69:     def unbind(self, triplet, func):
jpayne@69:         doit = lambda: self.bindedfuncs[triplet[2]][triplet[0]].remove(func)
jpayne@69:         if not self.ishandlerrunning:
jpayne@69:             doit()
jpayne@69:         else:
jpayne@69:             self.doafterhandler.append(doit)
jpayne@69: 
jpayne@69:     def __del__(self):
jpayne@69:         for seq, id in self.handlerids:
jpayne@69:             try:
jpayne@69:                 self.widget.unbind(self.widgetinst, seq, id)
jpayne@69:             except tkinter.TclError as e:
jpayne@69:                 if not APPLICATION_GONE in e.args[0]:
jpayne@69:                     raise
jpayne@69: 
jpayne@69: # define the list of event types to be handled by MultiEvent. the order is
jpayne@69: # compatible with the definition of event type constants.
jpayne@69: _types = (
jpayne@69:     ("KeyPress", "Key"), ("KeyRelease",), ("ButtonPress", "Button"),
jpayne@69:     ("ButtonRelease",), ("Activate",), ("Circulate",), ("Colormap",),
jpayne@69:     ("Configure",), ("Deactivate",), ("Destroy",), ("Enter",), ("Expose",),
jpayne@69:     ("FocusIn",), ("FocusOut",), ("Gravity",), ("Leave",), ("Map",),
jpayne@69:     ("Motion",), ("MouseWheel",), ("Property",), ("Reparent",), ("Unmap",),
jpayne@69:     ("Visibility",),
jpayne@69: )
jpayne@69: 
jpayne@69: # which binder should be used for every event type?
jpayne@69: _binder_classes = (_ComplexBinder,) * 4 + (_SimpleBinder,) * (len(_types)-4)
jpayne@69: 
jpayne@69: # A dictionary to map a type name into its number
jpayne@69: _type_names = dict([(name, number)
jpayne@69:                      for number in range(len(_types))
jpayne@69:                      for name in _types[number]])
jpayne@69: 
jpayne@69: _keysym_re = re.compile(r"^\w+$")
jpayne@69: _button_re = re.compile(r"^[1-5]$")
jpayne@69: def _parse_sequence(sequence):
jpayne@69:     """Get a string which should describe an event sequence. If it is
jpayne@69:     successfully parsed as one, return a tuple containing the state (as an int),
jpayne@69:     the event type (as an index of _types), and the detail - None if none, or a
jpayne@69:     string if there is one. If the parsing is unsuccessful, return None.
jpayne@69:     """
jpayne@69:     if not sequence or sequence[0] != '<' or sequence[-1] != '>':
jpayne@69:         return None
jpayne@69:     words = sequence[1:-1].split('-')
jpayne@69:     modifiers = 0
jpayne@69:     while words and words[0] in _modifier_names:
jpayne@69:         modifiers |= 1 << _modifier_names[words[0]]
jpayne@69:         del words[0]
jpayne@69:     if words and words[0] in _type_names:
jpayne@69:         type = _type_names[words[0]]
jpayne@69:         del words[0]
jpayne@69:     else:
jpayne@69:         return None
jpayne@69:     if _binder_classes[type] is _SimpleBinder:
jpayne@69:         if modifiers or words:
jpayne@69:             return None
jpayne@69:         else:
jpayne@69:             detail = None
jpayne@69:     else:
jpayne@69:         # _ComplexBinder
jpayne@69:         if type in [_type_names[s] for s in ("KeyPress", "KeyRelease")]:
jpayne@69:             type_re = _keysym_re
jpayne@69:         else:
jpayne@69:             type_re = _button_re
jpayne@69: 
jpayne@69:         if not words:
jpayne@69:             detail = None
jpayne@69:         elif len(words) == 1 and type_re.match(words[0]):
jpayne@69:             detail = words[0]
jpayne@69:         else:
jpayne@69:             return None
jpayne@69: 
jpayne@69:     return modifiers, type, detail
jpayne@69: 
jpayne@69: def _triplet_to_sequence(triplet):
jpayne@69:     if triplet[2]:
jpayne@69:         return '<'+_state_names[triplet[0]]+_types[triplet[1]][0]+'-'+ \
jpayne@69:                triplet[2]+'>'
jpayne@69:     else:
jpayne@69:         return '<'+_state_names[triplet[0]]+_types[triplet[1]][0]+'>'
jpayne@69: 
jpayne@69: _multicall_dict = {}
jpayne@69: def MultiCallCreator(widget):
jpayne@69:     """Return a MultiCall class which inherits its methods from the
jpayne@69:     given widget class (for example, Tkinter.Text). This is used
jpayne@69:     instead of a templating mechanism.
jpayne@69:     """
jpayne@69:     if widget in _multicall_dict:
jpayne@69:         return _multicall_dict[widget]
jpayne@69: 
jpayne@69:     class MultiCall (widget):
jpayne@69:         assert issubclass(widget, tkinter.Misc)
jpayne@69: 
jpayne@69:         def __init__(self, *args, **kwargs):
jpayne@69:             widget.__init__(self, *args, **kwargs)
jpayne@69:             # a dictionary which maps a virtual event to a tuple with:
jpayne@69:             #  0. the function binded
jpayne@69:             #  1. a list of triplets - the sequences it is binded to
jpayne@69:             self.__eventinfo = {}
jpayne@69:             self.__binders = [_binder_classes[i](i, widget, self)
jpayne@69:                               for i in range(len(_types))]
jpayne@69: 
jpayne@69:         def bind(self, sequence=None, func=None, add=None):
jpayne@69:             #print("bind(%s, %s, %s)" % (sequence, func, add),
jpayne@69:             #      file=sys.__stderr__)
jpayne@69:             if type(sequence) is str and len(sequence) > 2 and \
jpayne@69:                sequence[:2] == "<<" and sequence[-2:] == ">>":
jpayne@69:                 if sequence in self.__eventinfo:
jpayne@69:                     ei = self.__eventinfo[sequence]
jpayne@69:                     if ei[0] is not None:
jpayne@69:                         for triplet in ei[1]:
jpayne@69:                             self.__binders[triplet[1]].unbind(triplet, ei[0])
jpayne@69:                     ei[0] = func
jpayne@69:                     if ei[0] is not None:
jpayne@69:                         for triplet in ei[1]:
jpayne@69:                             self.__binders[triplet[1]].bind(triplet, func)
jpayne@69:                 else:
jpayne@69:                     self.__eventinfo[sequence] = [func, []]
jpayne@69:             return widget.bind(self, sequence, func, add)
jpayne@69: 
jpayne@69:         def unbind(self, sequence, funcid=None):
jpayne@69:             if type(sequence) is str and len(sequence) > 2 and \
jpayne@69:                sequence[:2] == "<<" and sequence[-2:] == ">>" and \
jpayne@69:                sequence in self.__eventinfo:
jpayne@69:                 func, triplets = self.__eventinfo[sequence]
jpayne@69:                 if func is not None:
jpayne@69:                     for triplet in triplets:
jpayne@69:                         self.__binders[triplet[1]].unbind(triplet, func)
jpayne@69:                     self.__eventinfo[sequence][0] = None
jpayne@69:             return widget.unbind(self, sequence, funcid)
jpayne@69: 
jpayne@69:         def event_add(self, virtual, *sequences):
jpayne@69:             #print("event_add(%s, %s)" % (repr(virtual), repr(sequences)),
jpayne@69:             #      file=sys.__stderr__)
jpayne@69:             if virtual not in self.__eventinfo:
jpayne@69:                 self.__eventinfo[virtual] = [None, []]
jpayne@69: 
jpayne@69:             func, triplets = self.__eventinfo[virtual]
jpayne@69:             for seq in sequences:
jpayne@69:                 triplet = _parse_sequence(seq)
jpayne@69:                 if triplet is None:
jpayne@69:                     #print("Tkinter event_add(%s)" % seq, file=sys.__stderr__)
jpayne@69:                     widget.event_add(self, virtual, seq)
jpayne@69:                 else:
jpayne@69:                     if func is not None:
jpayne@69:                         self.__binders[triplet[1]].bind(triplet, func)
jpayne@69:                     triplets.append(triplet)
jpayne@69: 
jpayne@69:         def event_delete(self, virtual, *sequences):
jpayne@69:             if virtual not in self.__eventinfo:
jpayne@69:                 return
jpayne@69:             func, triplets = self.__eventinfo[virtual]
jpayne@69:             for seq in sequences:
jpayne@69:                 triplet = _parse_sequence(seq)
jpayne@69:                 if triplet is None:
jpayne@69:                     #print("Tkinter event_delete: %s" % seq, file=sys.__stderr__)
jpayne@69:                     widget.event_delete(self, virtual, seq)
jpayne@69:                 else:
jpayne@69:                     if func is not None:
jpayne@69:                         self.__binders[triplet[1]].unbind(triplet, func)
jpayne@69:                     triplets.remove(triplet)
jpayne@69: 
jpayne@69:         def event_info(self, virtual=None):
jpayne@69:             if virtual is None or virtual not in self.__eventinfo:
jpayne@69:                 return widget.event_info(self, virtual)
jpayne@69:             else:
jpayne@69:                 return tuple(map(_triplet_to_sequence,
jpayne@69:                                  self.__eventinfo[virtual][1])) + \
jpayne@69:                        widget.event_info(self, virtual)
jpayne@69: 
jpayne@69:         def __del__(self):
jpayne@69:             for virtual in self.__eventinfo:
jpayne@69:                 func, triplets = self.__eventinfo[virtual]
jpayne@69:                 if func:
jpayne@69:                     for triplet in triplets:
jpayne@69:                         try:
jpayne@69:                             self.__binders[triplet[1]].unbind(triplet, func)
jpayne@69:                         except tkinter.TclError as e:
jpayne@69:                             if not APPLICATION_GONE in e.args[0]:
jpayne@69:                                 raise
jpayne@69: 
jpayne@69:     _multicall_dict[widget] = MultiCall
jpayne@69:     return MultiCall
jpayne@69: 
jpayne@69: 
jpayne@69: def _multi_call(parent):  # htest #
jpayne@69:     top = tkinter.Toplevel(parent)
jpayne@69:     top.title("Test MultiCall")
jpayne@69:     x, y = map(int, parent.geometry().split('+')[1:])
jpayne@69:     top.geometry("+%d+%d" % (x, y + 175))
jpayne@69:     text = MultiCallCreator(tkinter.Text)(top)
jpayne@69:     text.pack()
jpayne@69:     def bindseq(seq, n=[0]):
jpayne@69:         def handler(event):
jpayne@69:             print(seq)
jpayne@69:         text.bind("<<handler%d>>"%n[0], handler)
jpayne@69:         text.event_add("<<handler%d>>"%n[0], seq)
jpayne@69:         n[0] += 1
jpayne@69:     bindseq("<Key>")
jpayne@69:     bindseq("<Control-Key>")
jpayne@69:     bindseq("<Alt-Key-a>")
jpayne@69:     bindseq("<Control-Key-a>")
jpayne@69:     bindseq("<Alt-Control-Key-a>")
jpayne@69:     bindseq("<Key-b>")
jpayne@69:     bindseq("<Control-Button-1>")
jpayne@69:     bindseq("<Button-2>")
jpayne@69:     bindseq("<Alt-Button-1>")
jpayne@69:     bindseq("<FocusOut>")
jpayne@69:     bindseq("<Enter>")
jpayne@69:     bindseq("<Leave>")
jpayne@69: 
jpayne@69: if __name__ == "__main__":
jpayne@69:     from unittest import main
jpayne@69:     main('idlelib.idle_test.test_mainmenu', verbosity=2, exit=False)
jpayne@69: 
jpayne@69:     from idlelib.idle_test.htest import run
jpayne@69:     run(_multi_call)