How to list all the files/folder in a direcotry in QlistWidget?

How can i list all the files and folders of a directory in the QlistWidget. LIke i want to list all the files and folders in /media/USB folder.
And also i want to know how can i capture the double click event of a item in a QlistWidget. Because i have two QlistWidget,in one widget directory path is shown and in another widget i want to list all the files/folders when i select the directory path from first widget. Please provide code example if any.

Best would be using QFileSystemModelwith QListView.
Check the documentation for examples. You can also refer Qt Demos for the Dir View example

And what about the event capture when a particular item is selected in the list view?

Read the model and view classes in assistant.
Check out their signals.