Today I was using Alert.show() while building a RadioButtonGroup change handler and noticed something interesting.
If you use your mouse to change the values of a RadioButtonGroup, Alert.show() will behave like a proper modal dialog.
However, if you use your keyboard’s arrow keys to toggle the values, the focus remains with your RadioButtonGroup.
The lesson here is since the focus remains with my RadioButtonGroup, you can continue to change the values all you want via keyboard.
In my situation, I kept receiving Alert.show()s, instead of one.
Try it for yourself.
First click on a RadioButton below, and notice that the Alert.show() keeps you from clicking on the RadioButtonGroup until you OK the prompt.
Now try the same thing again using your keyboard. If you do it enough times, the prompts will cover up the stage completely.