title: Xamarin Forms Maps iOS bounds - show all pins on the screen
body: <p>Im using Xamarin Forms Maps, and I want to have the same feature on iOS as I have on Android devices - show all pins on the screen (appropriate position and zoom)</p>
  <p>What Im looking is &quot;Bounds&quot; property, but that I only found on XF.GoogleMaps which nuget I dont use.</p>
  <p>for Android in my custom renderer I pout LatLngBounds class and made a builder, thats works just fine, but on iOS I didnt find a solution.</p>
  <p>Thanks</p>
  <p><strong>UPDATE #1:</strong>
  Is this a right method in iOS renderer to put ShowAnnotations? And how to re-pack it to MkAnnotation from Pin model?</p>
  <pre><code>        protected override void OnElementChanged(ElementChangedEventArgs&lt;View&gt; e)
          {
              base.OnElementChanged(e);
  
              if (e.OldElement != null)
              {
                  var nativeMap = Control as MKMapView;
                  nativeMap.GetViewForAnnotation = null;
                  nativeMap.ZoomEnabled = true;
                 
                  nativeMap.CalloutAccessoryControlTapped -= OnCalloutAccessoryControlTapped;
                  nativeMap.DidSelectAnnotationView -= OnDidSelectAnnotationView;
                  nativeMap.DidDeselectAnnotationView -= OnDidDeselectAnnotationView;
              }
  
              if (e.NewElement != null)
              {
                  var formsMap = (CustomMap)e.NewElement;
                  var nativeMap = Control as MKMapView;
                  customPins = formsMap.CustomPins;
  
                  //MKAnnotation an = formsMap.CustomPins;
                  var numberOfPins = formsMap.CustomPins.Count;
                  MKAnnotation[] anotationArray = new MKAnnotation[numberOfPins];
  
                  for (int i = 0; i &lt; numberOfPins; i++)
                  {
                      anotationArray[0].Coordinate = customPins.ElementAt(0).Position...
                  }
                  foreach (var pin in formsMap.CustomPins)
                  {
  
                  }
                
                  nativeMap.ZoomEnabled = true;
                  nativeMap.GetViewForAnnotation = GetViewForAnnotation;
                  nativeMap.CalloutAccessoryControlTapped += OnCalloutAccessoryControlTapped;
                  nativeMap.DidSelectAnnotationView += OnDidSelectAnnotationView;
                  nativeMap.DidDeselectAnnotationView += OnDidDeselectAnnotationView;
              }
          }
  </code></pre>