---
title: RtkJoinButton
description: API reference for RtkJoinButton component (Android Library)
image: https://developers.cloudflare.com/dev-products-preview.png
---

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# RtkJoinButton

A button that performs the room join operation. Displays "Join" by default and changes to "Joining..." during the join process. Automatically disables after a successful join.

## Methods

| Method   | Parameters                                                | Description                                                                                                                                                                                                                                                     |
| -------- | --------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| activate | meeting: RealtimeKitClient, localUserNameField: EditText? | Bind the button to the meeting state. Pass an optional EditText reference to validate the display name before joining — if the user has canEditDisplayName permission and the field is blank, the button shows a "Please enter name" toast and blocks the join. |

## Usage Examples

### Basic Usage

```

<com.cloudflare.realtimekit.ui.view.RtkJoinButton

    android:id="@+id/rtk_join_button"

    android:layout_width="wrap_content"

    android:layout_height="48dp"

    app:rtk_btn_variant="primary" />


```

### With Methods

Kotlin

```

val joinButton = findViewById<RtkJoinButton>(R.id.rtk_join_button)

val nameField = findViewById<EditText>(R.id.name_field)

joinButton.activate(meeting, nameField)


```

```json
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```