It looks like you are trying to create mobile MXML skin in a 'Flex' project. To use mobile components/skins, create a new 'Flex Mobile' project and create an AS Class extending from spark.skins.mobile.ButtonSkin and use it as skinClass.
Note: spark.skins.mobile.ButtonSkin is a skin class in mobiletheme project.
It is a mobile project that I am working in.The specific scenario is this:
- Open a mobile view in Design Mode
- Right click on Button
- Choose 'Create Skin...' from the context menu
- Enter anything into the 'package' or 'name' fields and I get this error: 'The skin specified to copy is not valid.' Note that Host component is pre-populated as 'spark.components.Button' and 'Create as copy of' is pre-populated and selected as 'spark.skins.mobile.ButtonSkin'.
I suspect this is a bug in the Flex 4.5 pre-release...but would like to know for sure.
Since no one answered and I was looking for a similar problem, here is what I did:
- the theme is located in the installation folder: ~\4.5.0\frameworks\themes\Mobile\mobile.swc
- I've imported the Theme from the Appearance View
- I've selected the mobile theme as my current theme and I am still not able to find the spark.skins.mobile.ButtonSkin
here it says it is a preview: Reference
so, it might not be available yet.