# Widget.ICallback interface

Namespace: [Eto](https://eto.picoe.ca/api/namespace/eto.md) · Assembly: [Eto](https://eto.picoe.ca/api/assembly/eto.md)

```cs
public interface Widget.ICallback
```

> Base callback interface for all widgets

**Derived types:** [Application.ICallback](https://eto.picoe.ca/api/type/eto.forms.application.icallback.md), [Clipboard.ICallback](https://eto.picoe.ca/api/type/eto.forms.clipboard.icallback.md), [ContextMenu.ICallback](https://eto.picoe.ca/api/type/eto.forms.contextmenu.icallback.md), [Control.ICallback](https://eto.picoe.ca/api/type/eto.forms.control.icallback.md), [CustomCell.ICallback](https://eto.picoe.ca/api/type/eto.forms.customcell.icallback.md), [DrawableCell.ICallback](https://eto.picoe.ca/api/type/eto.forms.drawablecell.icallback.md), [FontDialog.ICallback](https://eto.picoe.ca/api/type/eto.forms.fontdialog.icallback.md), [Gesture.ICallback](https://eto.picoe.ca/api/type/eto.forms.gesture.icallback.md), [MenuItem.ICallback](https://eto.picoe.ca/api/type/eto.forms.menuitem.icallback.md), [PrintDocument.ICallback](https://eto.picoe.ca/api/type/eto.forms.printdocument.icallback.md), [SegmentedItem.ICallback](https://eto.picoe.ca/api/type/eto.forms.segmenteditem.icallback.md), [Thread.ICallback](https://eto.picoe.ca/api/type/eto.threading.thread.icallback.md), [TrayIndicator.ICallback](https://eto.picoe.ca/api/type/eto.forms.trayindicator.icallback.md), [UITimer.ICallback](https://eto.picoe.ca/api/type/eto.forms.uitimer.icallback.md)