Trigger a loader after seleting an item in a combox

I’m using vaadin 8 and I have a combox with a list of value. Each time a user select an element in the combobox, I update the list of column in a treegrid. Since this operation can take few seconds, I would like to display the loader when the user select the element in the combobox, so he can know that an action is runing.

Do you have any idea ? Thank you for your help.

Does anyone have a workarround or a solution for this issue ? I tried my best but I could not find a solution for this issue.

Any help ?

SOS any help or idea ?

Any idea or help ???

Any help ?

any thought ?

Actually there is already a loading indicator at any Vaadin page. By default, it looks like thin blue stripe at the very bottom. You can adjust your theme to make it more visible or look different.

And I filed a ticked related to the topic.
https://github.com/vaadin/framework/issues/9729