c# - Trying to set a device specific scale on an ActivityIndicator in Xamarin XAML causes a crash -

we have xamarin.forms app converting code behind xaml. have used onplatform successfully, causing crash when setting scale of our activityindicator. testing on ios simulator. here's code:

<activityindicator isrunning="true" color="white" horizontaloptions="center" verticaloptions="startandexpand">       <activityindicator.scale>         <onplatform x:typearguments="x:double" ios="4.0" android="3.0" />       </activityindicator.scale>     </activityindicator> 

in contrast, these 2 work:

<activityindicator isrunning="true" color="white" horizontaloptions="center" verticaloptions="startandexpand">       <activityindicator.scale>         4.0       </activityindicator.scale>     </activityindicator> 

-

<activityindicator isrunning="true" color="white" horizontaloptions="center" verticaloptions="startandexpand" scale="4.0">     </activityindicator> 

try this

<activityindicator isrunning="true" color="white" horizontaloptions="center" verticaloptions="startandexpand">   <activityindicator.scale>     <onplatform x:typearguments="x:double" ios="4.0" android="3.0" />   </activityindicator.scale> </activityindicator>  

it's type argument. double isn't type, double is.