how to implement a wait indication while processing

Question

I have an xpage where the rendering is false and when it is loaded calls in the BeforeRenderResponse event a java bean, whose code mounts an html from a table with data, and passes that html as a parameter to be consumed in a web service, which returns a pdf file as an array of bytes. This pdf is displayed on the page, however when the html is very large, this conversion to pdf and the page display takes a long time. I would like to display an animated gif or progress indicator so that the wait becomes more user friendly, I tried to implement it in many ways without success. Is there any way to implement this wait.

Answer 1

I would choose for something like an extra interface with a loading icon.

Pop-up an extra interface (as bald as possible, no titlebars nothing), add a minimalistic processing .gif icon and force close the interface when the wait is over.