title: How to display an "Open File" popup withoug using Win32 API
body: <p>I'm working on the editor for my game engine. At the moment, to load in a project, you have to type in the full path of the project file, which is annoying, and slow. How can I display a file popup box to select a file and then return it's path as a string? I am using Windows, but I would prefer not to use the Win32 API, for cross-platform purposes. My project uses Dear ImGui, so is there a way to harness that to display a list of files that can be selected? What I need to know how to do is to grab a list of drives, files and folders, and somehow store them in a tree (maybe something similar to an <code>std::vector</code> of <code>std::maps</code>?) which I can use with ImGui to create a popup where you can select files from different drives and folders.</p>