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PredictiveBack.md

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Predictive Back

Predictive Back is a navigation pattern tied to gesture navigation which shows the user a glimpse of where swiping back will bring them. Before completing a swipe, the user can decide to continue to the previous view or stay in the current view.

In Android 13 (T / API level 33), the OS introduced support for predictive back-to-home, which shows the user a preview of the home screen when swiping back to exit an app.

With Android 14 (U / API level 34), the OS adds support for in-app predictive back, which apps can take advantage of to show the user previous destinations when swiping back within the app itself.

Design & API documentation

Usage

To opt in to predictive back, apps must:

  1. Migrate from the legacy back handling APIs (Activity#onBackPressed, KeyEvent.KEYCODE_BACK, etc.) to the more recently introduced "back callback" APIs (OnBackAnimationCallback, OnBackPressedCallback, etc.). This involves flipping the android:enableOnBackInvokedCallback manifest flag to true, and registering callbacks to handle back pressed on Android T and above. More details on this general back migration can be found at the Framework & AndroidX Predictive Back developer guide.

  2. Upgrade to MDC-Android library version 1.10.0 or above.

Once completing these steps, you will get most of the predictive back animations within Material Components for free on Android U devices. See the section below to understand which components support predictive back and to learn about special considerations for each component.

Predictive Back Material Components

The following Material Components support predictive back behavior and animations:

  • Search bar (automatically for SearchView set up with SearchBar)
  • Bottom sheet (automatically for modal, standard requires integration)
  • Side sheet (automatically for modal, standard and coplanar require integration)
  • Navigation drawer (automatically for NavigationView within DrawerLayout)

Note: The Material Components above only automatically handle back on API Level 33+, and when the android:enableOnBackInvokedCallback manifest flag to true. This is to be consistent with the behavior of other AndroidX and Framework views, as well as to avoid taking precedence over any pre-existing back handling behavior that has already been implemented by apps.

Future predictive back support is planned for the following Material Components:

  • Navigation bar / Bottom navigation view
  • Navigation rail

Talks

Blog Posts