Annotation

Use annotation to draw over shared content. Both users and hosts can annotate during screen sharing.

Set up annotation

1. Check if the annotation feature is supported.

   // To check if annotation feature is supported
   ZMVideoSDK.shared()?.getShareHelper()?.isAnnotationFeatureSupport())
   // If you are the share owner, you can check if your viewer has annotation rights.
   ZMVideoSDK.shared()?.getShareHelper()?.isViewerAnnotationDisabled()
   // If you are the share owner, you can enable or disable your viewer from annotation rights.
   ZMVideoSDK.shared()?.getShareHelper()?.disableViewerAnnotation(true/false)
   

   If it is supported, continue.

2. Set up screen sharing.

   Now you can use annotation in your implementation.

Start and stop annotation

In order to start annotation, the viewer must first have already subscribed to a shared view and input the same view to create a new ZMVideoSDKAnnotationHelper from the share helper.

// Same as before, get the user's share canvas that you want to subscribe to
let userShareCanvas: ZMVideoSDKVideoCanvas
// Render the user's share stream into your view of choice. (This view is required for annotation)
usersShareCanvas.subscribe(with: view, aspectMode: .panAndScan, andResolution: ._Auto)
// Create annotation helper using the same view above and check for permission again
if let annotationHelper = ZMVideoSDK.shared()?.getShareHelper()?.createAnnotationHelper(cell.speakerView), annotationHelper.canDoAnnotation() {
    annotationHelper.startAnnotation()
    // To stop annotation later
    annotationHelper.stopAnnotation()
}

Annotation tools

There are a list of annotation tools available. The full list of tools is located under ZoomVideoSDKAnnotationToolType.

// Enum of ZMVideoSDKAnnotationToolType
ZMVideoSDKAnnotationToolType_None,
ZMVideoSDKAnnotationToolType_Pen,
ZMVideoSDKAnnotationToolType_HighLighter,
ZMVideoSDKAnnotationToolType_AutoLine,
ZMVideoSDKAnnotationToolType_AutoRectangle,
ZMVideoSDKAnnotationToolType_AutoEllipse,
ZMVideoSDKAnnotationToolType_AutoArrow,
ZMVideoSDKAnnotationToolType_AutoRectangleFill,
ZMVideoSDKAnnotationToolType_AutoEllipseFill,
ZMVideoSDKAnnotationToolType_SpotLight,
ZMVideoSDKAnnotationToolType_Arrow,
ZMVideoSDKAnnotationToolType_ERASER,
ZMVideoSDKAnnotationToolType_Textbox,
ZMVideoSDKAnnotationToolType_Picker,
ZMVideoSDKAnnotationToolType_AutoRectangleSemiFill,
ZMVideoSDKAnnotationToolType_AutoEllipseSemiFill,
ZMVideoSDKAnnotationToolType_AutoDoubleArrow,
ZMVideoSDKAnnotationToolType_AutoDiamond,
ZMVideoSDKAnnotationToolType_AutoStampArrow,
ZMVideoSDKAnnotationToolType_AutoStampCheck,
ZMVideoSDKAnnotationToolType_AutoStampX,
ZMVideoSDKAnnotationToolType_AutoStampStar,
ZMVideoSDKAnnotationToolType_AutoStampHeart,
ZMVideoSDKAnnotationToolType_AutoStampQm

Upon selecting the tool, the user can also get or set the current tool's color or width.

// Get/set tool type
annotationHelper.getToolType()
annotationHelper.setToolType(.pen)
// Get/set tool's color - Color
annotationHelper.getToolColor()
annotationHelper.setToolColor(.red)
// Get/set tool's width - long
annotationHelper.getToolWidth()
annotationHelper.setToolWidth(5)

Other annotation methods

You can also undo or redo annotations. And you can clear all annotations, just your own, or just others' annotations.

annotationHelper.undo()
annotationHelper.redo()
annotationHelper.clear(.all) // .all, .my, .others

See the ZMVideoSDKAnnotationHelper class reference and the ZMVideoSDKShareHelper class reference for details.

Destroy annotation

Once annotation is no longer valid or required, you can destory it by calling the destroyAnnotationHelper method in the the ZMVideoSDKShareHelper class.

ZoomVideoSDK.shareInstance()?.getShareHelper()?.destroy(annotationHelper)