private FunctionImageToggle initTestData(out Image i)
 {
     i = new Image {Source = null};
     _val = 0;
     FunctionImageToggle testData = new FunctionImageToggle(new BitmapImage(),
         ref i,
         () => { _val = 1; }
         ,
         () => { _val = 2; });
     return testData;
 }
 private FunctionImageToggle<int> initGenericFunctionImageToggle(out Image i)
 {
     i = new Image() {Source = null};
     _val = 0;
     var testData = new FunctionImageToggle<int>(new BitmapImage(),
         ref i,
         val => { _val = val; }
         ,
         val => { _val = val; });
     return testData;
 }