Request: File Browser Example?

[awesomebytes]

Hello, I wonder if there is any example of a file browser "widget"?

I'm looking into making an app where the user needs to choose a bunch of files, ideally clicking on a checkbox to make clear that file will be taken into account (and I'll need to show some summary data of the file size accumulated from all the files selected in between other little bits of info).
I've seen that Shiny has a file input, but that does not let you have an interactive experience (e.g. showing the number of files selected, total size, a sublist of all files selected in case the user changed folder but had files selected in another folder...).

Is there any kind of example that I have overlooked maybe? Or anyone can point me to an example of some wrapped up widget that I can use to get started? Thank you and sorry for the noise!