Tree View

A widget intended to replace treeviews in a Windows app.
The usual treeviews are riddled with usability problems, hopefully this one will fare better.

Here's how it works : on any given hierarchical level, a single click selects an item and a double-click either open a file or drill-down a folder. You cannot disclose a folder to reveal its content, there's always only one hierarchical level displayed at a time.

Clicking on the header reveals some kind of a vertically stacked breadcrumb for fast access to previous levels. You could also select files and drag them to said header, revealing the vertical breadcrumb, then drop the files on the desired level.

This solution is a trade-off, sacrifying easy file micro-management features (eg, it's harder to move a file to superior level folder) for an easier navigation and less footprint. What do you think?

Feedback welcome!