带有 Robolectric 的 AnimatorProxy 中的 Nineoldandroids NullPointerException

Nineoldandroids NullPointerException in AnimatorProxy with Robolectric

我正在测试的视图有动画,当我用 Robolectric 测试时,它似乎出错了。动画是使用 Nineoldandroids 实现兼容性的简单滑动。在 Robolectric 之外一切正常,但是我的单元测试因空指针而崩溃:

10:34:35.419 [DEBUG] [TestEventLogger]     java.lang.NullPointerException
10:34:35.419 [DEBUG] [TestEventLogger]      at com.nineoldandroids.view.animation.AnimatorProxy.applyTransformation(AnimatorProxy.java:316)
10:34:35.419 [DEBUG] [TestEventLogger]      at android.view.animation.Animation.getTransformation(Animation.java:870)
10:34:35.420 [DEBUG] [TestEventLogger]      at org.robolectric.shadows.ShadowView.run(ShadowView.java:492)
10:34:35.420 [DEBUG] [TestEventLogger]      at org.robolectric.util.Scheduler.runOrQueueRunnable(Scheduler.java:218)
10:34:35.420 [DEBUG] [TestEventLogger]      at org.robolectric.util.Scheduler.postDelayed(Scheduler.java:73)
10:34:35.421 [DEBUG] [TestEventLogger]      at org.robolectric.shadows.ShadowChoreographer.postCallbackDelayed(ShadowChoreographer.java:44)
10:34:35.421 [DEBUG] [TestEventLogger]      at android.view.Choreographer.postCallbackDelayed(Choreographer.java)
10:34:35.427 [DEBUG] [TestEventLogger]      at org.robolectric.shadows.ShadowView.setAnimation(ShadowView.java:487)
10:34:35.429 [DEBUG] [TestEventLogger]      at android.view.View.setAnimation(View.java)
10:34:35.431 [DEBUG] [TestEventLogger]      at com.nineoldandroids.view.animation.AnimatorProxy.<init>(AnimatorProxy.java:66)
10:34:35.432 [DEBUG] [TestEventLogger]      at com.nineoldandroids.view.animation.AnimatorProxy.wrap(AnimatorProxy.java:38)
10:34:35.432 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.PreHoneycombCompat.get(PreHoneycombCompat.java:161)
10:34:35.432 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.PreHoneycombCompat.get(PreHoneycombCompat.java:153)
10:34:35.432 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.PropertyValuesHolder.setupSetterAndGetter(PropertyValuesHolder.java:510)
10:34:35.433 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.ObjectAnimator.initAnimation(ObjectAnimator.java:410)
10:34:35.433 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.ValueAnimator.setCurrentPlayTime(ValueAnimator.java:538)
10:34:35.433 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.ValueAnimator.start(ValueAnimator.java:928)
10:34:35.433 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.ValueAnimator.start(ValueAnimator.java:951)
10:34:35.433 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.ObjectAnimator.start(ObjectAnimator.java:385)
10:34:35.433 [DEBUG] [TestEventLogger]      at com.nineoldandroids.animation.AnimatorSet.start(AnimatorSet.java:502)

如果我在我的代码中添加一个检查以仅将 nineoldandroids 用于 API <11 并且默认情况下使用 android 本机动画,测试就可以顺利通过。从 nineoldandroids 来源我可以看到它在这一行上是空指针:

View view = mView.get();

其中 mView 是 mView = new WeakReference<View>(view);

关于如何从测试用例而不是我的应用代码中理想地解决这个问题有什么建议吗?

似乎正在发生的事情是,在 AnimationProxy 完全初始化之前,为列表元素设置动画的 Nineoldandroid 动画由 UI/Main 循环程序执行。这可能是由于在 Robolectric 3.

中更好地模拟了 Android 线程架构

我通过调用解决了这个问题:

ShadowLooper.pauseMainLooper();

将此调用放在任何可以在 Nineoldandroids 中启动动画的方法之前。

更新:

这给我带来了更多麻烦,而且上面的解决方法对于执行动画的每一段代码都很烦人,所以我分叉并修复了它,非常小的变化:

https://github.com/apinder/NineOldAndroids/commit/6d399685dc5b3932e3b806d4d7d2f27123e1ca36