# GoogleMobileAds Framework Reference

# GADDisplayAdMeasurement


    @interface GADDisplayAdMeasurement : NSObject

Measurement used for display custom native ad formats.
- `


  ### [view](https://developers.google.com/admob/ios/api/reference/Classes/GADDisplayAdMeasurement#/c:objc(cs)GADDisplayAdMeasurement(py)view)


  ` Ad view used to measure viewability. This property can be modified before or after starting
  display ad measurement. Must be accessed on the main thread.

  #### Declaration

  Swift

      weak var view: UIView? { get set }

  Objective-C

      @property (nonatomic, weak, nullable) UIView *view;

- `


  ### [-startWithError:](https://developers.google.com/admob/ios/api/reference/Classes/GADDisplayAdMeasurement#/c:objc(cs)GADDisplayAdMeasurement(im)startWithError:)


  ` Starts OMID viewability measurement for display ads. Returns whether OMID viewability was
  started and sets \|error\| if unable to start. Once started, all subsequent calls return YES and
  have no effect. Must be called on the main thread.

  #### Declaration

  Swift

      func start() throws

  Objective-C

      - (BOOL)startWithError:(NSError *_Nullable *_Nullable)error;