# MainToolbarButton(MainToolbarContent, Action)

> Specify the content and function of a main toolbar button.

## Definition

* **Type:** Constructor
* **Namespace:** [UnityEditor.Toolbars](/engine/6000.6/script-reference/unityeditor/toolbars.md)
* **Assembly:** UnityEditor

```csharp
public MainToolbarButton(MainToolbarContent content, Action action)
```

### Parameters

**** (\[MainToolbarContent]\(/engine/6000.6/script-reference/unityeditor/toolbars/maintoolbarcontent)): The visual content for this button.**** (\[Action]\(https\://learn.microsoft.com/dotnet/api/system.action)): The action to perform when the user selects the button.