What is the need for a fragment

Branch - todo-mvp

I can't understand the use of a fragment here. The only use it see is that it is used to separate the view and the activity.

Should I always create a fragment to separate the view even if Im not needing a fragment.

https://github.com/googlesamples/android-architecture/tree/todo-mvp/todoapp/app/src/main/java/com/example/android/architecture/blueprints/todoapp/taskdetail

Start by reading the todo-mvp taskdetail source at todoapp/app/src/main/java/com/example/android/architecture/blueprints/todoapp/taskdetail and trace how its fragment and activity are used. The issue does not specify a documentation change or a completion criterion, so clarify the intended explanation before attempting work.

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