### Question:
SliderValueAdapter implements GriffonPivotAdapter, org.apache.pivot.wtk.SliderValueListener { public void valueChanged(org.apache.pivot.wtk.Slider arg0, int arg1) { if (valueChanged != null) { valueChanged.call(arg0, arg1); } }  CallableWithArgs<Void> getValueChanged(); void setValueChanged(CallableWithArgs<Void> valueChanged); void valueChanged(org.apache.pivot.wtk.Slider arg0, int arg1);  }### Answer:
@Test public void testValueChanged() { final boolean[] invoked = new boolean[1]; CallableWithArgs<Void> callable = new CallableWithArgs<Void>() { public Void call(Object... args) { invoked[0] = true; return null; } }; assertNull(adapter.getValueChanged()); adapter.valueChanged(null, 0); assertFalse(invoked[0]); adapter.setValueChanged(callable); adapter.valueChanged(null, 0); assertTrue(invoked[0]); }