Humble Objects and the View Boundary
Apply the Humble Object pattern to keep view code thin and testable, pushing all decisions into testable presenters at the presentation boundary.
The Hardest Code to Test
UI code is notoriously hard to test: it touches frameworks, screens, and event loops.
The Humble Object pattern solves this by splitting behavior so that the hard-to-test part becomes humble — nearly logic-free.
The Pattern in One Idea
Separate code into two parts across a boundary:
- A humble part: thin, dumb, hard to test (the view).
- A testable part: holds all the logic (the presenter).
Almost all behavior moves to the testable side.
All lessons in this course
- Presenters and View Models
- Adapting to Web Frameworks
- Testing the Presentation Layer
- Humble Objects and the View Boundary