~~Title: OnViewerEvent ~~
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The **OnViewerEvent** event can be implemented by a [[:scripting:script_add-ins|script add-in]] to receive notification whenever certain events occur in the [[:additional_functionality:viewing_images|standalone image viewer]]. One possible use would be a script that automatically displays a floating toolbar whenever a standalone viewer is active, and hides it again when the window goes inactive or closes. 


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$$ (#)**Method Name:**
$$ OnViewerEvent
$$ (#)**Argument Type:**
$$ **[[..:scripting_objects:viewereventdata|ViewerEventData]]** 
$$ (#)**Return Type:**
$$ //none//
$$ (#)**Description:**
$$ The **ViewerEventData.viewer** property identifies the **[[..:scripting_objects:viewer|Viewer]]** that the event occurred in. The **event** property returns a string identifying the event that occurred, and if applicable the **item** property identifies the **Item** involved.\\
</commandtable>