FragmentScenario

class FragmentScenario<F : Fragment> : Closeable

FragmentScenario provides API to start and drive a Fragment's lifecycle state for testing. It works with arbitrary fragments and works consistently across different versions of the Android framework.

FragmentScenario only supports androidx.fragment.app.Fragment. If you are using a deprecated fragment class such as android.support.v4.app.Fragment or android.app.Fragment, please update your code to androidx.fragment.app.Fragment.

If your testing Fragment has a dependency to specific theme such as Theme.AppCompat, use the theme ID parameter in launch method.

Parameters
<F : Fragment>

The Fragment class being tested
See also
ActivityScenario

a scenario API for Activity

Summary

Nested types

FragmentAction interface should be implemented by any class whose instances are intended to be executed by the main thread.

Public companion functions
FragmentScenario<F>
<F : Fragment> launch(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    factory: FragmentFactory?
)

Launches a Fragment with given arguments hosted by an empty FragmentActivity using the given FragmentFactory and waits for it to reach the resumed state.
FragmentScenario<F>
<F : Fragment> launch(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    themeResId: @StyleRes Int,
    factory: FragmentFactory?
)

Launches a Fragment with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach the resumed state.
FragmentScenario<F>
<F : Fragment> launch(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    themeResId: @StyleRes Int,
    initialState: Lifecycle.State,
    factory: FragmentFactory?
)

Launches a Fragment with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach initialState.
FragmentScenario<F>
<F : Fragment> launchInContainer(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    factory: FragmentFactory?
)

Launches a Fragment in the Activity's root view container android.R.id.content, with given arguments hosted by an empty FragmentActivity using the given FragmentFactory and waits for it to reach the resumed state.
FragmentScenario<F>
<F : Fragment> launchInContainer(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    themeResId: @StyleRes Int,
    factory: FragmentFactory?
)

Launches a Fragment in the Activity's root view container android.R.id.content, with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach the resumed state.
FragmentScenario<F>
<F : Fragment> launchInContainer(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    themeResId: @StyleRes Int,
    initialState: Lifecycle.State,
    factory: FragmentFactory?
)

Launches a Fragment in the Activity's root view container android.R.id.content, with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach initialState.

Public functions
open Unit

Finishes the managed fragments and cleans up device's state.
FragmentScenario<F>

Moves Fragment state to a new state.
FragmentScenario<F>

Runs a given action on the current Activity's main thread.
FragmentScenario<F>

Recreates the host Activity.

Extension functions
inline T
<F : Fragment, T : Any> FragmentScenario<F>.withFragment(
    crossinline block: F.() -> T
)

Run block using FragmentScenario.onFragment, returning the result of the block.

Public companion functions

launch

Added in 1.3.0
fun <F : Fragment> launch(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    factory: FragmentFactory?
): FragmentScenario<F>

Launches a Fragment with given arguments hosted by an empty FragmentActivity using the given FragmentFactory and waits for it to reach the resumed state.

This method cannot be called from the main thread.

Parameters
fragmentClass: Class<F>

a fragment class to instantiate
fragmentArgs: Bundle?

a bundle to passed into fragment
factory: FragmentFactory?

a fragment factory to use or null to use default factory

launch

Added in 1.3.0
fun <F : Fragment> launch(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    themeResId: @StyleRes Int,
    factory: FragmentFactory?
): FragmentScenario<F>

Launches a Fragment with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach the resumed state.

This method cannot be called from the main thread.

Parameters
fragmentClass: Class<F>

a fragment class to instantiate
fragmentArgs: Bundle?

a bundle to passed into fragment
themeResId: @StyleRes Int

a style resource id to be set to the host activity's theme
factory: FragmentFactory?

a fragment factory to use or null to use default factory

launch

Added in 1.3.0
fun <F : Fragment> launch(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle? = null,
    themeResId: @StyleRes Int = R.style.FragmentScenarioEmptyFragmentActivityTheme,
    initialState: Lifecycle.State = Lifecycle.State.RESUMED,
    factory: FragmentFactory? = null
): FragmentScenario<F>

Launches a Fragment with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach initialState.

This method cannot be called from the main thread.

Parameters
fragmentClass: Class<F>

a fragment class to instantiate
fragmentArgs: Bundle? = null

a bundle to passed into fragment
themeResId: @StyleRes Int = R.style.FragmentScenarioEmptyFragmentActivityTheme

a style resource id to be set to the host activity's theme
initialState: Lifecycle.State = Lifecycle.State.RESUMED

The initial Lifecycle.State. Passing in DESTROYED will result in an IllegalArgumentException.
factory: FragmentFactory? = null

a fragment factory to use or null to use default factory

launchInContainer

Added in 1.3.0
fun <F : Fragment> launchInContainer(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    factory: FragmentFactory?
): FragmentScenario<F>

Launches a Fragment in the Activity's root view container android.R.id.content, with given arguments hosted by an empty FragmentActivity using the given FragmentFactory and waits for it to reach the resumed state.

This method cannot be called from the main thread.

Parameters
fragmentClass: Class<F>

a fragment class to instantiate
fragmentArgs: Bundle?

a bundle to passed into fragment
factory: FragmentFactory?

a fragment factory to use or null to use default factory

launchInContainer

Added in 1.3.0
fun <F : Fragment> launchInContainer(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle?,
    themeResId: @StyleRes Int,
    factory: FragmentFactory?
): FragmentScenario<F>

Launches a Fragment in the Activity's root view container android.R.id.content, with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach the resumed state.

This method cannot be called from the main thread.

Parameters
fragmentClass: Class<F>

a fragment class to instantiate
fragmentArgs: Bundle?

a bundle to passed into fragment
themeResId: @StyleRes Int

a style resource id to be set to the host activity's theme
factory: FragmentFactory?

a fragment factory to use or null to use default factory

launchInContainer

Added in 1.3.0
fun <F : Fragment> launchInContainer(
    fragmentClass: Class<F>,
    fragmentArgs: Bundle? = null,
    themeResId: @StyleRes Int = R.style.FragmentScenarioEmptyFragmentActivityTheme,
    initialState: Lifecycle.State = Lifecycle.State.RESUMED,
    factory: FragmentFactory? = null
): FragmentScenario<F>

Launches a Fragment in the Activity's root view container android.R.id.content, with given arguments hosted by an empty FragmentActivity themed by themeResId, using the given FragmentFactory and waits for it to reach initialState.

This method cannot be called from the main thread.

Parameters
fragmentClass: Class<F>

a fragment class to instantiate
fragmentArgs: Bundle? = null

a bundle to passed into fragment
themeResId: @StyleRes Int = R.style.FragmentScenarioEmptyFragmentActivityTheme

a style resource id to be set to the host activity's theme
initialState: Lifecycle.State = Lifecycle.State.RESUMED

The initial Lifecycle.State. Passing in DESTROYED will result in an IllegalArgumentException.
factory: FragmentFactory? = null

a fragment factory to use or null to use default factory

Public functions

close

Added in 1.4.0
open fun close(): Unit

Finishes the managed fragments and cleans up device's state. This method blocks execution until the host activity becomes Lifecycle.State.DESTROYED.

moveToState

Added in 1.1.0
fun moveToState(newState: Lifecycle.State): FragmentScenario<F>

Moves Fragment state to a new state.

If a new state and current state are the same, this method does nothing. It accepts all Lifecycle.States. DESTROYED is a terminal state. You cannot move to any other state after the Fragment reaches that state.

This method cannot be called from the main thread.

onFragment

Added in 1.1.0
fun onFragment(action: FragmentScenario.FragmentAction<F>): FragmentScenario<F>

Runs a given action on the current Activity's main thread.

Note that you should never keep Fragment reference passed into your action because it can be recreated at anytime during state transitions.

Throwing an exception from action makes the host Activity crash. You can inspect the exception in logcat outputs.

This method cannot be called from the main thread.

recreate

Added in 1.1.0
fun recreate(): FragmentScenario<F>

Recreates the host Activity.

After this method call, it is ensured that the Fragment state goes back to the same state as its previous state.

This method cannot be called from the main thread.

Extension functions

withFragment

inline fun <F : Fragment, T : Any> FragmentScenario<F>.withFragment(
    crossinline block: F.() -> T
): T

Run block using FragmentScenario.onFragment, returning the result of the block.

If any exceptions are raised while running block, they are rethrown.