[android-components](../../index.md) / [mozilla.components.feature.customtabs](../index.md) / [AbstractCustomTabsService](index.md) / [postMessage](./post-message.md)

# postMessage

`protected open fun postMessage(sessionToken: CustomTabsSessionToken?, message: `[`String`](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html)`?, extras: <ERROR CLASS>?): `[`Int`](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html) [(source)](https://github.com/mozilla-mobile/android-components/blob/master/components/feature/customtabs/src/main/java/mozilla/components/feature/customtabs/AbstractCustomTabsService.kt#L73)