The AIR NativeWindow API is a staple of desktop AIR applications, used to open multiple windows on the screen, each with its own stage. On mobile devices and TVs, the class is unsupported. So how does an application go about opening a window?
It doesn’t. On mobile devices and TVs, AIR applications can render only to the single available stage. The stage is automatically create and made visible when the application launches, and remains available until the application exits. In other words, it behaves essentially the same as the Stage does for Flash Player content.
Most code need concern itself only with the stage, and in this way can be made more portable between desktop, mobile, and TV deployment. For example, the stage directly provides information about its size. It also retains the ability to enter full-screen mode, and on mobile devices provides information about screen orientation.
If you have code that needs to check at runtime whether or not it can create new windows, simply check NativeWindow.isSupported.