> 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. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.apryse.com/xamarin/annotation/toolmanager-events.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.