running FXML-LoginDemo and then pressing out side the appLoggin window and slidding the finger into appLoggin window cause to the exception to be thrown

Command line used:
ejdk1.8.0-arm/bin/java -Dcom.sun.javafx.virtualKeyboard=javafx -Djavafx.platform=eglfb -Dlens.input.touch.MoveSensitivity=3 -Dlog.lens=severe -cp udev-refactoring/artifacts/armv6-vfp/sdk/rt/lib/ext/jfxrt.jar:FXML-LoginDemo.jar demo.Main