The primary milestone is to improve to Kotlin 1.8.0 or larger, which is required for different Predictive Again dependencies.
Again-to-home animation milestone
The back-to-home animation is the keystone predictive again animation.
To get this animation, add android:enableOnBackInvokedCallback=true in your AndroidManifest.xml on your root exercise if you’re a multi-activity app (see per-activity opt-in) or on the software stage if you’re a single-activity app. After this, you’ll see each the back-to-home animation and a cross-task animation the place relevant, that are seen to customers in Android 15+ and behind a developer choice in Android 13 and 14.
In case you are intercepting again occasions in your root exercise (e.g. MainActivity), you possibly can proceed to take action however you’ll want to make use of supported APIs and also you gained’t get the back-to-home animation. Because of this, we usually advocate you solely intercept again occasions for UI logic; for instance, to indicate a dialog asking the person to save lots of earlier than they stop.
See the Add help for the predictive again gesture information for extra particulars.
Migrate all actions milestone
In case you are a multi-activity app, you’ll must opt-in and deal with again occasions inside these actions too to get a system managed cross-activity animation. Study extra about per-activity opt-in, obtainable for gadgets working Android 14+. The cross-activity animation is seen to customers in Android 15+ and behind a developer choice in Android 13 and 14.
Customized cross exercise animations are additionally obtainable with overrideActivityTransition.
Fragment milestone
Subsequent, you’ll wish to focus in your fragment animations and transitions. This requires updating to AndroidX fragment 1.7.0 and transition 1.5.0 or later and utilizing Animator or AndroidX Transitions. Assuming these necessities are met, your present fragment animations and transitions will animate consistent with the again gesture. You too can use materials movement with fragments. Most materials motions help predictive again as of 1.12.02-alpha02 or larger, together with MaterialFadeThrough, MaterialSharedAxis and MaterialFade.
Don’t attempt to make your fragment transitions appear like the system’s cross-activity transition. We advocate this full display floor transition as an alternative.
Study extra about Fragments and Predictive Again.
Materials Parts milestone
Lastly, you’ll wish to benefit from the Materials Part View animations obtainable for Predictive Again. Study extra about obtainable parts.
After this, you’ve accomplished your quest to help Predictive Again animations in your view based mostly app.
[Optional] AndroidX Transitions milestone
Should you’re up for extra, you may also guarantee your AndroidX transitions are supported with Predictive Again. Learn extra about AndroidX Transitions and the Predictive Again Progress APIs.
