%% This module is actually handwritten see ../api_gen/wx_extra/wxEvtHandler.erl
%%
%% @doc The Event handler.
%%
%% To get events from wxwidgets objects you subscribe to them by
%% calling connect/[2-3]. Events are sent as messages, if no callback
%% was supplied These messages will be {@link wx(). #wx{}} where
%% EventRecord is a record that depends on the {@link
%% wxEventType(). event type}. The records are defined in:
%% wx/include/wx.hrl.
%%
%% If a callback was supplied to connect, the callback will be invoked
%% (in another process) to handle the event. The callback should be of
%% arity 2. fun(EventRecord::wx(), EventObject::wxObject()).
%%
%% Beware that the callback will be in executed in new process each time.
%%
%% <a href="http://www.wxwidgets.org/manuals/stable/wx_wxevthandler.html">
%% The orginal documentation</a>.
%%
%% @headerfile "../../include/wx.hrl"
%%
%%@type wxEvtHandler(). An object reference
-module(wxEvtHandler).
-include("wxe.hrl").
-include("../include/wx.hrl").
%% API
-export([connect/2, connect/3, disconnect/1, disconnect/2, disconnect/3]).
%% internal exports
-export([connect_impl/3, disconnect_impl/2, disconnect_impl/3,
new_evt_listener/0, destroy_evt_listener/1,
get_callback/1, replace_fun_with_id/2]).
-record(evh, {et=null,id=?wxID_ANY,lastId=?wxID_ANY,skip=undefined,userdata=[],cb=0}).
%% @spec (This::wxEvtHandler(), EventType::wxEventType()) -> ok
%% @doc Equivalent to {@link connect/3. connect(This, EventType, [])}
connect(This, EventType) ->
connect(This, EventType, []).
%% @spec (This::wxEvtHandler(), EventType::wxEventType(), [Options]) -> ok
%% @doc This function subscribes the to events of EventType,
%% in the range id, lastId. The events will be received as messages
%% if no callback is supplied.
%%
%% Options:
%% {id, integer()}, The identifier (or first of the identifier range) to be
%% associated with this event handler.
%% Default ?wxID_ANY
%% {lastId, integer()}, The second part of the identifier range.
%% If used 'id' must be set as the starting identifier range.
%% Default ?wxID_ANY
%% {skip, boolean()}, If skip is true further event_handlers will be called.
%% This is not used if the 'callback' option is used.
%% Default false.
%% {callback, function()} Use a callback fun(EventRecord::wx(), EventObject::wxObject())
%% to process the event. Default not specfied i.e. a message will
%% be delivered to the process calling this function.
%% {userData, term()} An erlang term that will be sent with the event. Default: [].
connect(This=#wx_ref{type=ThisT}, EventType, Options) ->
EvH = parse_opts(Options, #evh{et=EventType}),
?CLASS(ThisT,wxEvtHandler),
case wxe_util:connect_cb(This, EvH) of
ok -> ok;
{badarg, event_type} ->
erlang:error({badarg,EventType})
end.
parse_opts([{callback,Fun}|R], Opts) when is_function(Fun) ->
%% Check Fun Arity?
parse_opts(R, Opts#evh{cb=Fun});
parse_opts([callback|R], Opts) ->
parse_opts(R, Opts#evh{cb=self()});
parse_opts([{userData, UserData}|R],Opts) ->
parse_opts(R, Opts#evh{userdata=UserData});
parse_opts([{skip, Skip}|R],Opts) when is_boolean(Skip) ->
parse_opts(R, Opts#evh{skip=Skip});
parse_opts([{id, Id}|R],Opts) when is_integer(Id) ->
parse_opts(R, Opts#evh{id=Id});
parse_opts([{lastId, Id}|R],Opts) when is_integer(Id) ->
parse_opts(R, Opts#evh{lastId=Id});
parse_opts([_BadArg|R], Opts) ->
parse_opts(R, Opts);
parse_opts([], Opts = #evh{id=Id,lastId=Lid,skip=Skip, cb=CB}) ->
if
Skip =/= undefined andalso CB =/= 0 ->
erlang:error({badarg, {combined, skip, callback}});
Lid =/= ?wxID_ANY andalso Id =:= ?wxID_ANY ->
erlang:error({badarg, no_start_identifier_range});
Skip =:= undefined -> %% Default
Opts#evh{skip=false};
true ->
Opts
end.
%% @spec (This::wxEvtHandler()) -> true | false
%% @doc Equivalent to {@link disconnect/3. disconnect(This, null, [])}
%% Can also have an optional callback Fun() as an additional last argument.
disconnect(This=#wx_ref{type=ThisT,ref=_ThisRef}) ->
?CLASS(ThisT,wxEvtHandler),
disconnect(This, null, []).
%% @spec (This::wxEvtHandler(), EventType::wxEventType()) -> true | false
%% @doc Equivalent to {@link disconnect/3. disconnect(This, EventType, [])}
disconnect(This=#wx_ref{type=ThisT,ref=_ThisRef}, EventType) when is_atom(EventType) ->
?CLASS(ThisT,wxEvtHandler),
disconnect(This, EventType, []).
%% @spec (This::wxEvtHandler(), EventType::wxEventType(), Opts) -> true | false
%% @doc See <a href="http://www.wxwidgets.org/manuals/stable/wx_wxevthandler.html#wxevthandlerdisconnect">external documentation</a>
%% This function unsubscribes the process or callback fun from the event handler.
%% EventType may be the atom 'null' to match any eventtype.
%% Notice that the options skip and userdata is not used to match the eventhandler.
disconnect(This=#wx_ref{type=ThisT,ref=_ThisRef}, EventType, Opts) ->
?CLASS(ThisT,wxEvtHandler),
EvH = parse_opts(Opts, #evh{et=EventType}),
case wxe_util:disconnect_cb(This, EvH) of
{badarg, event_type} ->
erlang:error({badarg,EventType});
Bool ->
Bool
end.
%% @hidden
connect_impl(#wx_ref{type=wxeEvtListener,ref=EvtList},
#wx_ref{type=ThisT,ref=ThisRef},
#evh{id=Winid, lastId=LastId, et=EventType,
skip=Skip, userdata=Userdata, cb=FunID})
when is_integer(FunID)->
EventTypeBin = list_to_binary([atom_to_list(EventType)|[0]]),
ThisTypeBin = list_to_binary([atom_to_list(ThisT)|[0]]),
UD = if Userdata =:= [] -> 0;
true ->
wxe_util:send_bin(term_to_binary(Userdata)),
1
end,
wxe_util:call(100, <<EvtList:32/?UI,ThisRef:32/?UI,
Winid:32/?UI,LastId:32/?UI,
(wxe_util:from_bool(Skip)):32/?UI,
UD:32/?UI,
FunID:32/?UI,
(size(EventTypeBin)):32/?UI,
(size(ThisTypeBin)):32/?UI,
%% Note no alignment
EventTypeBin/binary,ThisTypeBin/binary>>).
%% @hidden
disconnect_impl(Listener, Object) ->
disconnect_impl(Listener, Object, #evh{}).
%% @hidden
disconnect_impl(#wx_ref{type=wxeEvtListener,ref=EvtList},
#wx_ref{type=_ThisT,ref=ThisRef},
#evh{id=Winid, lastId=LastId, et=EventType}) ->
EventTypeBin = list_to_binary([atom_to_list(EventType)|[0]]),
wxe_util:call(101, <<EvtList:32/?UI,
ThisRef:32/?UI,Winid:32/?UI,LastId:32/?UI,
(size(EventTypeBin)):32/?UI,
%% Note no alignment
EventTypeBin/binary>>).
%% @hidden
new_evt_listener() ->
wxe_util:call(98, <<>>).
%% @hidden
destroy_evt_listener(#wx_ref{type=wxeEvtListener,ref=EvtList}) ->
wxe_util:call(99, <<EvtList:32/?UI>>).
%% @hidden
get_callback(#evh{cb=Callback}) ->
Callback.
%% @hidden
replace_fun_with_id(Evh, Id) ->
Evh#evh{cb=Id}.
