fixes #37 corrected FileSelector error (#38)

* fixes #37  corrected FileSelector error

* package hotfix release 2.2.1

Author: rjackey

deploy/Toolbox Packaging Project.prj

@@ -29,7 +29,7 @@ https://www.mathworks.com/matlabcentral/fileexchange/66235-widgets-toolbox
 
 Planning a complex or business-critical app? MathWorks Consulting can advise you on design and architecture: https://www.mathworks.com/services/consulting/proven-solutions/software-development-with-matlab.html</param.description>
     <param.screenshot>${PROJECT_ROOT}\widgets_logo.png</param.screenshot>
-    <param.version>2.2.0</param.version>
+    <param.version>2.2.1</param.version>
     <param.output>${PROJECT_ROOT}\Widgets Toolbox - MATLAB App Designer Components.mltbx</param.output>
     <param.products.name>
       <item>MATLAB</item>

widgets/+wt/FileSelector.m

@@ -355,8 +355,9 @@ function setValueFromFullPath(obj,fullPath)
                 numAbove = max(numel(rootParts) - idx + 1, 0);
                 if numAbove>0
 
-                    obj.throwError("Path '%s' is not within the root directory '%s'.",...
-                        fullPath, obj.RootDirectory);
+                    msg = "Select a path beneath the root:" + ...
+                        newline + newline + obj.RootDirectory;
+                    obj.throwError(msg);
 
                 else