> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/xamarin/annotation/toolmanager-events.md). # Events Learn how to get notified of events fired from ToolManager in Xamarin.Android and Xamarin.iOS. Register callbacks for touch, annotation, quick menu events, and more. Explore event APIs and delegate me You can take certain actions based on events and triggers. {% tabs %} {% tab title="Android" %} ## Get notified of events fired from ToolManager in Xamarin.Android {% hint style="info" %} **This tutorial only applies to Xamarin.Android. See Xamarin.iOS equivalent here .** {% endhint %} The [`ToolManager`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html) exposes a number of events to allow a subscriber to be notified of events fired from the tools package. There are [a number of methods](/xamarin/annotation/annotation-handling.md#android) that allow you to modify the behaviour of the tools themselves. The methods discussed here are simple notifications, so that the app may coordinate as necessary. See all event APIs here: [ToolManager events](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#events). | Scenario | Method to use to register your callback | | ---------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Get notified on touch events | Example: [`LongPress`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_LongPress), [`SingleTapConfirmed`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_SingleTapConfirmed) etc. | | Get notified on annotation events | Example: [`InterceptAnnotationHandling`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_InterceptAnnotationHandling) | | Get notified on annotation modification events | Example: [`AnnotationsAdded`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_AnnotationsAdded), [`AnnotationsModified`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_AnnotationsModified), [`AnnotationsRemoved`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_AnnotationsRemoved) etc. | | Get notified on quick menu events | Example: [`QuickMenuClicked`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_QuickMenuClicked) | | Get notified on tool changed event | [`ToolChanged`](https://sdk.apryse.com/api/xamarinandroid/tools/api/pdftron.PDF.Tools.ToolManager.html#pdftron_PDF_Tools_ToolManager_ToolChanged) | | {% endtab %} | | {% tab title="iOS" %} ## Get notified of events fired from ToolManager in Xamarin.iOS {% hint style="info" %} **This tutorial only applies to Xamarin.iOS. See Xamarin.Android equivalent here .** {% endhint %} The [`ToolManager`](https://sdk.apryse.com/api/xamarinios/tools/api/pdftron.PDF.Tools.PTToolManager.html)['s](https://sdk.apryse.com/api/xamarinios/tools/api/pdftron.PDF.Tools.PTToolManager.html)[`ToolManagerDelegate`](https://sdk.apryse.com/api/xamarinios/tools/api/pdftron.PDF.Tools.PTToolManagerDelegate.html) exposes a number of delegate methods to allow a subscriber to be notified of events that are managed by the tools framework. There are [a number of methods](/xamarin/basic-operations/basics/tools/intercept-annotation-handling.md) that allow you to modify the behaviour of the tools themselves. The methods discussed here are simple notifications, so that the app may coordinate as necessary. 1. [`-toolManagerToolChanged:`](https://sdk.apryse.com/api/xamarinios/tools/api/pdftron.PDF.Tools.PTToolManager.html#pdftron_PDF_Tools_PTToolManager_ToolManagerToolChanged) This method is called when the tool changes, for example changing the "active" tool in a toolbar. 2. [`-toolManager:annotationAdded:onPageNumber:`](https://sdk.apryse.com/api/xamarinios/tools/api/pdftron.PDF.Tools.PTToolManager.html#pdftron_PDF_Tools_PTToolManager_AnnotationAdded) [`-toolManager:annotationModified:onPageNumber:`](https://sdk.apryse.com/api/xamarinios/tools/api/pdftron.PDF.Tools.PTToolManager.html#pdftron_PDF_Tools_PTToolManager_AnnotationModified) [`-toolManager:annotationRemoved:onPageNumber:`](https://sdk.apryse.com/api/xamarinios/tools/api/pdftron.PDF.Tools.PTToolManager.html#pdftron_PDF_Tools_PTToolManager_AnnotationRemoved) These methods are called just after an annotation is added, modified or deleted. {% endtab %} {% endtabs %} --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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