# TriggerBuilders.Trigger

Artifact: [androidx.wear.protolayout:protolayout](https://developer.android.com/jetpack/androidx/releases/wear-protolayout) [View Source](https://cs.android.com/search?q=file:androidx/wear/protolayout/TriggerBuilders.java+class:androidx.wear.protolayout.TriggerBuilders.Trigger) Added in [1.0.0](https://developer.android.com/jetpack/androidx/releases/wear-protolayout#1.0.0)

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```
@RequiresSchemaVersion(major = 1, minor = 200)
public interface TriggerBuilders.Trigger
```

<br />

Known direct subclasses [TriggerBuilders.OnVisibleOnceTrigger](https://developer.android.com/reference/androidx/wear/protolayout/TriggerBuilders.OnVisibleOnceTrigger), [TriggerBuilders.OnVisibleTrigger](https://developer.android.com/reference/androidx/wear/protolayout/TriggerBuilders.OnVisibleTrigger)

|---|---|
| `https://developer.android.com/reference/androidx/wear/protolayout/TriggerBuilders.OnVisibleOnceTrigger` | Triggers only once when the layout visibility state turns from invisible to fully visible for the first time. |
| `https://developer.android.com/reference/androidx/wear/protolayout/TriggerBuilders.OnVisibleTrigger` | Triggers when the layout visibility state turns from invisible to fully visible. |

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Interface defining the triggers that can be fired. These triggers can be used to allow acting on events. For example some animations can be set to start based on a trigger.