### Question:
SpinnerAdapter implements GriffonPivotAdapter, org.apache.pivot.wtk.SpinnerListener { public void spinnerDataChanged(org.apache.pivot.wtk.Spinner arg0, org.apache.pivot.collections.List<?> arg1) { if (spinnerDataChanged != null) { spinnerDataChanged.call(arg0, arg1); } }  CallableWithArgs<Void> getItemRendererChanged(); CallableWithArgs<Void> getSpinnerDataChanged(); CallableWithArgs<Void> getCircularChanged(); void setItemRendererChanged(CallableWithArgs<Void> itemRendererChanged); void setSpinnerDataChanged(CallableWithArgs<Void> spinnerDataChanged); void setCircularChanged(CallableWithArgs<Void> circularChanged); void itemRendererChanged(org.apache.pivot.wtk.Spinner arg0, org.apache.pivot.wtk.Spinner.ItemRenderer arg1); void spinnerDataChanged(org.apache.pivot.wtk.Spinner arg0, org.apache.pivot.collections.List<?> arg1); void circularChanged(org.apache.pivot.wtk.Spinner arg0);  }### Answer:
@Test public void testSpinnerDataChanged() { final boolean[] invoked = new boolean[1]; CallableWithArgs<Void> callable = new CallableWithArgs<Void>() { public Void call(Object... args) { invoked[0] = true; return null; } }; assertNull(adapter.getSpinnerDataChanged()); adapter.spinnerDataChanged(null, null); assertFalse(invoked[0]); adapter.setSpinnerDataChanged(callable); adapter.spinnerDataChanged(null, null); assertTrue(invoked[0]); }