# TestNavigationEventHandler

Artifact: [androidx.navigationevent:navigationevent-testing](https://developer.android.com/jetpack/androidx/releases/navigationevent) [View Source](https://cs.android.com/search?q=file:androidx/navigationevent/testing/TestNavigationEventHandler.kt+class:androidx.navigationevent.testing.TestNavigationEventHandler) Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

*** ** * ** ***

Common/All
- Cmn

  ```
  class TestNavigationEventHandler<T : NavigationEventInfo> : NavigationEventHandler<T>
  ```

|---|---|---|
| [kotlin.Any](https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-any/index.html) |||
| ↳ | [androidx.navigationevent.NavigationEventHandler](https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler)\<T\> ||
|   | ↳ | [androidx.navigationevent.testing.TestNavigationEventHandler](https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler) |

*** ** * ** ***

A test implementation of `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler` that records received events and invocation counts.

This class is primarily used in tests to verify that specific navigation event callbacks are triggered as expected. It captures the `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` objects and counts how many times each callback is fired.

| Parameters |
|---|---|
| `<T : https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventInfo>` | The `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventInfo` type this callback handles. |

## Summary

| ### Public constructors |
|---|---|
| `<T : https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventInfo> https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#TestNavigationEventHandler(androidx.navigationevent.NavigationEventInfo,kotlin.collections.List,kotlin.collections.List,kotlin.Boolean,kotlin.Function2,kotlin.Function2,kotlin.Function1,kotlin.Function1,kotlin.Boolean,kotlin.Function2,kotlin.Function2,kotlin.Function1,kotlin.Function1)( currentInfo: T, backInfo: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T>, forwardInfo: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T>, isForwardEnabled: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html, onForwardStarted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html, onForwardProgressed: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html, onForwardCancelled: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html, onForwardCompleted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html, isBackEnabled: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html, onBackStarted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html, onBackProgressed: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html, onBackCancelled: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html, onBackCompleted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html )` | Cmn |

| ### Protected functions |
|---|---|---|
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCancelled()()` Override this to handle the cancellation of a back navigation event. | Cmn |
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCompleted()()` Override this to handle the completion of a back navigation event. | Cmn |
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackProgressed(androidx.navigationevent.NavigationEvent)(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent)` Override this to handle the progress of an ongoing back navigation event. | Cmn |
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackStarted(androidx.navigationevent.NavigationEvent)(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent)` Override this to handle the beginning of a back navigation event. | Cmn |
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCancelled()()` Override this to handle the cancellation of a forward navigation event. | Cmn |
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCompleted()()` Override this to handle the completion of a forward navigation event. | Cmn |
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardProgressed(androidx.navigationevent.NavigationEvent)(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent)` Override this to handle the progress of an ongoing forward navigation event. | Cmn |
| `open https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardStarted(androidx.navigationevent.NavigationEvent)(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent)` Override this to handle the beginning of a forward navigation event. | Cmn |

| ### Public properties |
|---|---|---|
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCancelledInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCancelled()` has been invoked. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCompletedInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCompleted()` has been invoked. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent>` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackProgressedEvents()` All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackProgressed(androidx.navigationevent.NavigationEvent)`. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackProgressedInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackProgressed(androidx.navigationevent.NavigationEvent)` has been invoked. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent>` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackStartedEvents()` All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackStarted(androidx.navigationevent.NavigationEvent)`. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackStartedInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackStarted(androidx.navigationevent.NavigationEvent)` has been invoked. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCancelledInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCancelled()` has been invoked. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCompletedInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCompleted()` has been invoked. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent>` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardProgressedEvents()` All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardProgressed(androidx.navigationevent.NavigationEvent)`. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardProgressedInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardProgressed(androidx.navigationevent.NavigationEvent)` has been invoked. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent>` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardStartedEvents()` All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardStarted(androidx.navigationevent.NavigationEvent)`. | Cmn |
| `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-int/index.html` | `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardStartedInvocations()` Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardStarted(androidx.navigationevent.NavigationEvent)` has been invoked. | Cmn |

### Inherited functions

From [androidx.navigationevent.NavigationEventHandler](https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler) `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#remove()()`

Removes this handler from the `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventDispatcher` it is registered with.
Cmn `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#setInfo(androidx.navigationevent.NavigationEventInfo,kotlin.collections.List,kotlin.collections.List)(currentInfo: T, backInfo: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T>, forwardInfo: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T>)`

Sets the directional navigation context for this handler.
Cmn

### Inherited properties

From [androidx.navigationevent.NavigationEventHandler](https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler) `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T>` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#backInfo()`

Contextual information describing the application's *back* state for this handler.
Cmn `T` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#currentInfo()`

The contextual information representing the active destination for this handler.
Cmn `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T>` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#forwardInfo()`

Contextual information describing the application's *forward* state for this handler.
Cmn `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#isBackEnabled()`

Controls whether this handler is active and should be considered for back event dispatching.
Cmn `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#isForwardEnabled()`

Controls whether this handler is active and should be considered for forward event dispatching.
Cmn `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventTransitionState` `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventHandler#transitionState()`

The current transition state of this specific handler (e.g., `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventTransitionState.Idle` or `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventTransitionState.InProgress`).
Cmn

## Public constructors

### TestNavigationEventHandler

Cmn

```
<T : NavigationEventInfo> TestNavigationEventHandler(
    currentInfo: T,
    backInfo: List<T> = emptyList(),
    forwardInfo: List<T> = emptyList(),
    isForwardEnabled: Boolean = true,
    onForwardStarted: TestNavigationEventHandler<T>.(event: NavigationEvent) -> Unit = {},
    onForwardProgressed: TestNavigationEventHandler<T>.(event: NavigationEvent) -> Unit = {},
    onForwardCancelled: TestNavigationEventHandler<T>.() -> Unit = {},
    onForwardCompleted: TestNavigationEventHandler<T>.() -> Unit = {},
    isBackEnabled: Boolean = true,
    onBackStarted: TestNavigationEventHandler<T>.(event: NavigationEvent) -> Unit = {},
    onBackProgressed: TestNavigationEventHandler<T>.(event: NavigationEvent) -> Unit = {},
    onBackCancelled: TestNavigationEventHandler<T>.() -> Unit = {},
    onBackCompleted: TestNavigationEventHandler<T>.() -> Unit = {}
)
```

| Parameters |
|---|---|
| `<T : https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventInfo>` | The `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEventInfo` type this callback handles. |
| `currentInfo: T` | Initial current navigation info. |
| `backInfo: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T> = emptyList()` | Initial back stack info list. Defaults to empty. |
| `forwardInfo: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin.collections/-list/index.html<T> = emptyList()` | Initial forward stack info list. Defaults to empty. |
| `isForwardEnabled: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html = true` | Determines if forward callbacks should process events. Defaults to `true`. |
| `onForwardStarted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onForwardStarted` is called. |
| `onForwardProgressed: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onForwardProgressed` is called. |
| `onForwardCancelled: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onForwardCancelled` is called. |
| `onForwardCompleted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onForwardCompleted` is called. |
| `isBackEnabled: https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-boolean/index.html = true` | Determines if back callbacks should process events. Defaults to `true`. |
| `onBackStarted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onBackStarted` is called. |
| `onBackProgressed: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.(event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent) -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onBackProgressed` is called. |
| `onBackCancelled: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onBackCancelled` is called. |
| `onBackCompleted: https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler<T>.() -> https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unit/index.html = {}` | Optional lambda to execute when `onBackCompleted` is called. |

## Protected functions

### onBackCancelled

Cmn

```
protected open fun onBackCancelled(): Unit
```

Override this to handle the cancellation of a back navigation event.

This is called when the user cancels the navigation action, signaling that the UI should return to its original state.

### onBackCompleted

Cmn

```
protected open fun onBackCompleted(): Unit
```

Override this to handle the completion of a back navigation event.

This is called when the user commits to the back navigation action, signaling that the navigation should be finalized.

The default implementation throws an `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unsupported-operation-exception/index.html`. Any handler that can be completed **must** override this method to handle the navigation.

### onBackProgressed

Cmn

```
protected open fun onBackProgressed(event: NavigationEvent): Unit
```

Override this to handle the progress of an ongoing back navigation event.

This is called repeatedly during a gesture-driven back navigation to update the UI in real-time based on the user's input.

| Parameters |
|---|---|
| `event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` | The `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` containing progress information. |

### onBackStarted

Cmn

```
protected open fun onBackStarted(event: NavigationEvent): Unit
```

Override this to handle the beginning of a back navigation event.

This is called when a user action initiates a back navigation. It's the ideal place to prepare UI elements for a transition.

| Parameters |
|---|---|
| `event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` | The `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` that triggered this handler. |

### onForwardCancelled

Cmn

```
protected open fun onForwardCancelled(): Unit
```

Override this to handle the cancellation of a forward navigation event.

This is called when the user cancels the navigation action, signaling that the UI should return to its original state.

### onForwardCompleted

Cmn

```
protected open fun onForwardCompleted(): Unit
```

Override this to handle the completion of a forward navigation event.

This is called when the user commits to the forward navigation action, signaling that the navigation should be finalized.

The default implementation throws an `https://kotlinlang.org/api/core/kotlin-stdlib/kotlin/-unsupported-operation-exception/index.html`. Any handler that can be completed **must** override this method to handle the navigation.

### onForwardProgressed

Cmn

```
protected open fun onForwardProgressed(event: NavigationEvent): Unit
```

Override this to handle the progress of an ongoing forward navigation event.

This is called repeatedly during a gesture-driven forward navigation to update the UI in real-time based on the user's input.

| Parameters |
|---|---|
| `event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` | The `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` containing progress information. |

### onForwardStarted

Cmn

```
protected open fun onForwardStarted(event: NavigationEvent): Unit
```

Override this to handle the beginning of a forward navigation event.

This is called when a user action initiates a forward navigation. It's the ideal place to prepare UI elements for a transition.

| Parameters |
|---|---|
| `event: https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` | The `https://developer.android.com/reference/kotlin/androidx/navigationevent/NavigationEvent` that triggered this handler. |

## Public properties

### onBackCancelledInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onBackCancelledInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCancelled()` has been invoked.

### onBackCompletedInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onBackCompletedInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackCompleted()` has been invoked.

### onBackProgressedEvents

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onBackProgressedEvents: List<NavigationEvent>
```

All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackProgressed(androidx.navigationevent.NavigationEvent)`.

### onBackProgressedInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onBackProgressedInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackProgressed(androidx.navigationevent.NavigationEvent)` has been invoked.

### onBackStartedEvents

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onBackStartedEvents: List<NavigationEvent>
```

All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackStarted(androidx.navigationevent.NavigationEvent)`.

### onBackStartedInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onBackStartedInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onBackStarted(androidx.navigationevent.NavigationEvent)` has been invoked.

### onForwardCancelledInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onForwardCancelledInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCancelled()` has been invoked.

### onForwardCompletedInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onForwardCompletedInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardCompleted()` has been invoked.

### onForwardProgressedEvents

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onForwardProgressedEvents: List<NavigationEvent>
```

All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardProgressed(androidx.navigationevent.NavigationEvent)`.

### onForwardProgressedInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onForwardProgressedInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardProgressed(androidx.navigationevent.NavigationEvent)` has been invoked.

### onForwardStartedEvents

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onForwardStartedEvents: List<NavigationEvent>
```

All events received by `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardStarted(androidx.navigationevent.NavigationEvent)`.

### onForwardStartedInvocations

Cmn Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/navigationevent#1.0.0)

```
val onForwardStartedInvocations: Int
```

Number of times `https://developer.android.com/reference/kotlin/androidx/navigationevent/testing/TestNavigationEventHandler#onForwardStarted(androidx.navigationevent.NavigationEvent)` has been invoked.