Adds a text input field to a custom dialog window.
dlg_add_txt_input(handle, name) dlg_add_txt_input(handle, name, text)
hnd = dlg_new("My dialog"); dlg_add_label(hnd, "", "Name the first thing you see"); dlg_add_txt_input(hnd, "", "", "thething"); dlg_show(hnd); print("thething: ", thething);