Vim popup window not showing on successive events - vim

Question

I have the following plugin I wrote to test popup windows
"plugin/morning/morning.vim"
augroup morning_command_line_popup
autocmd!
au CmdlineLeave * call morning#close()
au CmdlineEnter * call morning#open()
au CmdlineChanged * call morning#update()
augroup END
"autoload/morning.vim"
function morning#open()
let opt = {}
let opt.border = []
let opt.minwidth = &columns / 3
let g:morning_window_handle = popup_create(":echo 'hi'", opt)
endfunction
function morning#close()
call popup_close(g:morning_window_handle)
endfunction
function morning#update()
call popup_show(g:morning_window_handle)
endfunction
The first time I enter the command line, the popup window appears. Every successive time that I enter the command line, it doesn't appear. I know the events are being fired and the functions are being called because if I put echom commands in the functions the messages show. Anyone know what could be wrong?

Answer 1

I figured out that if I redraw after showing the popup window, it seems to work consistently. I don't know if there's a reason why it won't redraw normally, or if doing this is extremely inefficient. This also has the side effect of overwriting wildmenu.
function morning#open()
let opt = {}
let opt.border = []
let opt.minwidth = &columns / 3
let g:morning_window_handle = popup_create(":echo 'hi'", opt)
redraw
endfunction
function morning#close()
call popup_close(g:morning_window_handle)
endfunction
function morning#update()
call popup_settext(g:morning_window_handle, string(getcmdline()))
call popup_show(g:morning_window_handle)
redraw
endfunction