question: @ Nullable public static File resolveLayout ( @ NotNull RenderResources resources , @ Nullable ResourceValue layout ) { if ( layout != null ) { layout = resources . resolveResValue ( layout ) ; } if ( layout == null ) { return null ; } String value = layout . getValue ( ) ; int depth = 0 ; while ( value != null && depth < MAX_RESOURCE_INDIRECTION ) { if ( DataBindingUtil . isBindingExpression ( value ) ) { value = DataBindingUtil . getBindingExprDefault ( value ) ; if ( value == null ) { return null ; } } if ( value . startsWith ( PREFIX_RESOURCE_REF ) ) { boolean isFramework = layout . isFramework ( ) ; layout = resources . findResValue ( value , isFramework ) ; if ( layout != null ) { value = layout . getValue ( ) ; } else { break ; } } else { File file = new File ( value ) ; if ( file . exists ( ) ) { return file ; } else { return null ; } } depth ++ ; } return null ; }
target:  Tries to resolve the given resource value to an actual layout file.