How do I define default animations for Navigation Actions?

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R.anim has the default animations defined (as final):

  • nav_default_enter_anim

  • nav_default_exit_anim

  • nav_default_pop_enter_anim

  • nav_default_pop_exit_anim

in order to change this behavior, you would have to use custom NavOptions,

because this is where those animation are being assigned to a NavAction.

one can assign these with the NavOptions.Builder:

protected NavOptions getNavOptions() {

    NavOptions navOptions = new NavOptions.Builder()
      .setEnterAnim(R.anim.default_enter_anim)
      .setExitAnim(R.anim.default_exit_anim)
      .setPopEnterAnim(R.anim.default_pop_enter_anim)
      .setPopExitAnim(R.anim.default_pop_exit_anim)
      .build();

    return navOptions;
}

most likely one would need to create a DefaultNavFragment, which extends class androidx.navigation.fragment (the documentation there does not seem completed yet).

So you can pass these NavOptions to the NavHostFragment like this:

NavHostFragment.findNavController(this).navigate(R.id.your_action_id, null, getNavOptions());

alternatively… when looking at the attrs.xml of that package; these animations are style-able:

<resources>
    <declare-styleable name="NavAction">
        <attr name="enterAnim" format="reference"/>
        <attr name="exitAnim" format="reference"/>
        <attr name="popEnterAnim" format="reference"/>
        <attr name="popExitAnim" format="reference"/>
        ...
    </declare-styleable>
</resources>

this means, one can define the according styles – and define these, as part of the theme…

one can define them in styles.xml:

<style name="Theme.Default" parent="Theme.AppCompat.Light.NoActionBar">

    <!-- these should be the correct ones -->
    <item name="NavAction_enterAnim">@anim/default_enter_anim</item>
    <item name="NavAction_exitAnim">@anim/default_exit_anim</item>
    <item name="NavAction_popEnterAnim">@anim/default_pop_enter_anim</item>
    <item name="NavAction_popExitAnim">@anim/default_pop_exit_anim</item>

</style>

One can also define the default animations in res/anim:

  • res/anim/nav_default_enter_anim.xml
  • res/anim/nav_default_exit_anim.xml
  • res/anim/nav_default_pop_enter_anim.xml
  • res/anim/nav_default_pop_exit_anim.xml

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