It means you have selected a nonvisual component that is not inherited
from any visual display Objects like sprite movie clicps or interactive
display object.Such component has no user interactivity at all and it will
most probbaly be used only by developer itself and it has no design stuff
involved So thats why you having this errror. You may select some other
component like button component and add it to the application and you will
see its both visual and non visual parts .
thats the odd part, it does that on startup, in a windowed application you get the design view. I'm getting it with only this in the mxml:
<?xml version="1.0" encoding="utf-8"?>
thats all that's there, tried to put a canvas in, an image, nothing seems to let me go into design view.
Ensure that when you created the project you specified a Flex web app, not an AIR app.
If you try to put an <mx:Application> tag in an AIR app, or even replace the <mx:WindowedApplication> tag of an AIR project with an <mx:Application> tag, it might not work.
I double checked that, even deleted the App and started over. I'm using Flex 3, and have the Flex 3.3 SDK installed. I can't think of any other reason why its not working. I even tried doing a tutorial the same way the tutorial told me to to make sure I wasn't missing anything, and its still not doing it right.
Maybe Project - Clean, or restart/reinstall FB?