I have a QFileSystemModel with a custom QSortFilterProxyModel and a custom QFileIconProvider.

My QFileIconProvider fetches file icons in another thread so that the file list can be populated more quickly - get file list first, populate list, and then get the icons in a seperate thread. So my QFileIconProvider::icon() override returns a blank icon until the information is available. How can I get QFileSystemModel to recognise when the new icon is available? I don't want want to refresh the entire list, as I want the list to update as and when the icons become available.