Android onStop（）在后台堆栈活动中正在进行动画时被延迟调用

Android onStop（）在完成活动B后调用不太晚。 +它在安卓7.0牛轧糖下运行良好

如果动画从onResume开始，并从onPause取消，则效果良好。但我想知道为什么

记录以下内容

Activity B : onPause
Activity A : onStart
Activity A : onResume
... after 10 seconds ...
Activity B : onStop
Activity B : onDestroy

活动A：启动动画

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    final ImageView imageview = (ImageView) findViewById(R.id.imageview);
    final Animation anim = AnimationUtils.loadAnimation(MainActivity.this, R.anim.animation);
    imageview.setAnimation(anim);
    anim.start();

    // startActivity after about 10 seconds
    startActivity(new Intent(this, ActivityB.class);
}

活动B：在调用onPause大约10秒后调用onStop

protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);

        Button button = (Button) findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                finish();
            }
        });
    }