tiles-session is a simple graphical session with basic window management functionality.


Build with tiles-session

Make sure //src/session/examples/tiles-session to your gn build args, e.g:

fx set <product>.<board> --with //src/session/examples/tiles-session

Launch tiles-session

ffx session launch fuchsia-pkg://fuchsia.com/tiles-session#meta/tiles-session.cm

Add your view

ffx session add fuchsia-pkg://fuchsia.com/flatland-examples#meta/flatland-view-provider-example.cmx

Current limitations

TODO(fxbug.dev/88656): update the following as features are added, and delete when fully-featured. Only one view is supported. Adding an additional view replaces the existing one.

Use cases

tile-session fills a few roles in the Fuchsia ecosystem:

  • educational: explain workings of a simple yet fully-functional session
  • testing: reliable basis for integration tests
  • development: support development by teams such as Input, Scenic, etc.
    • inspect
    • expose APIs for tests to query various conditions



There is a design tension between simplicity and featurefulness. Making this an accessible example requires simplicity. On the other hand, supporting test/dev use cases requires extra features and hence extra complexity. We aim for a balance.

As much as possible, the code for test/dev features should be encapsulated such that they don't confuse the reader who is just trying to gains an understanding of how a session works. The place(s) where this code is plugged in to the basic session should be clearly marked as rabbit holes that the reader may wish to avoid falling into.