@Override
            void onControlPoint2Moved(float cx, float cy) {
                cx2Label.setText("ControlX2: " + String.format("%.2f", cx));
                cy2Label.setText("ControlY2: " + String.format("%.2f", cy));
            }
Creates a cubic PathInterpolator, whose control points values can be changed
by the user dragging the handles around in the UI.
AnimationsInterpolatorPlayground/app/src/main/java/com/example/android/interpolatorplayground/MainActivity.java