Nullability of reference types in type of parameter 'sender' of 'void ImageClassification.UserControl_HandleDestroyed(object sender, EventArgs e)' doesn't match the target delegate 'EventHandler' (possibly because of nullability attributes).

Non-nullable field 'videoDevices' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable field 'videoSource' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable field 'TestmlContext' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable field 'TestpredictionEngine' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable event 'UserControlClosed' must contain a non-null value when exiting constructor. Consider declaring the event as nullable.

Non-nullable field 'videoDevices' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable field 'videoSource' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable field 'TestmlContext' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.