Application.connectStartup

gulong connectStartup(T)(T callback,  Flag!"After" after =  No.After) if (isCallable!T
    &&  is(ReturnType!T ==  void)
   && (Parameters!T.length <  1 || (ParameterStorageClassTuple!T[0]  ==  ParameterStorageClass.none &&  is(Parameters!T[0] :  gio.application.Application)))
   &&  Parameters!T.length <  2)

Connect to Startup signal.

The ::startup signal is emitted on the primary instance immediately after registration. See [gio.application.Application.register].

Parameters

`callback`	signal callback delegate or function to connect `void callback(gio.application.Application application)` `application` the instance the signal is connected to (optional)
`after`	Yes.After to execute callback after default handler, No.After to execute before (default)

Returns

Signal ID