Complicate Computing blocks ui update

[liukaizheng]

let on_click = |_| {
    let (fixed, set_fixed) = create_signal(true);
    let on_click = move |_| {
        set_fixed(false);
        // then do very expensive computation
       ....
       set_fixed(true);
};
view! {
    <div>
        <button on:click=on_click>
             { move ||  if fixed() {
                "Fix"
              } else {
                "Fixing"
              }}
         </button>
    </div>
}

I hope the button text will be "Fixing" when I click the button. But When the button is clicked to start doing expensive computation, The button text is still(always) "Fix". Who can help me