Action generated when a key is pressed or released. If the key is pressed and held several calls will occur.
int function(Ihandle *self, int c, int press); [in C] elem:keypress(c, press: number) -> (ret: number) [in IupLua3] elem:keypress_cb(c, press: number) -> (ret: number) [in IupLua5]
self: identifier of the element.
c: identifier of typed key. Please refer to the Keyboard Codes table for a list of possible values.
press: 1 is the user pressed the key or 0 otherwise.
This function may return IUP_CLOSE.