The SegmentedControl's Segments are distinct sections that strictly follow the native platform's expectations for a segmented control. It doesn't have an "ItemTemplate" approach you can use to get that styling (you'd also face a problem with removing the separator).
What you could try instead is use the RadBorder to make your own control like this because it will give you all the styling features I see in that screenshot. Then use a TapGestureRecognizer for the logic (be sure to make all contents InputTransparent).
Here's an example with just two RadBorder controls inside a Grid with two Labels:
For interaction logic in the MyCustomSwitch_OnTapped event handler, you can change the Label's TextColor.
Then you'd get this result at runtime:
Extra Credit - Animation
If you want the switch to animate left and right, take a look at Xamarin.Forms TranslateTo method. It works on any Xamarin.Forms view, you can replace the HoriztonalOptions value change with TranslateTo:
InnerBorder.TranslateTo(x-offset, y-offset, duration);
I hope this helps.
Lance | Technical Support Engineer, Principal
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