ArcGIS Pro 2.8 API Reference Guide
ZoomOutFixedAsync Method
Example 

ArcGIS.Desktop.Mapping Namespace > MapView Class : ZoomOutFixedAsync Method
The amount of time to navigate the view to the new camera position. If null it uses the default navigation duration.
Zoom the Camera out by a fixed amount.
Syntax
public Task<bool> ZoomOutFixedAsync( 
   Nullable<TimeSpan> duration
)
Public Function ZoomOutFixedAsync( _
   Optional ByVal duration As Nullable(Of TimeSpan) _
) As Task(Of Boolean)

Parameters

duration
The amount of time to navigate the view to the new camera position. If null it uses the default navigation duration.

Return Value

True if the navigation is completed, false if it was interrupted by another view navigation.
Example
Zoom out in the map view by a fixed amount.
public Task<bool> ZoomOutFixedAsync()
{
  //Get the active map view.
  var mapView = MapView.Active;
  if (mapView == null)
    return Task.FromResult(false);

  //Zoom in the map view by a fixed amount.
  return mapView.ZoomOutFixedAsync();
}
Requirements

Target Platforms: Windows 10, Windows 8.1

See Also

Reference

MapView Class
MapView Members