方法在第一次调用时可以获取到窗口内容，然后在窗口改变后返回null
这个log在第一次进入的时候打印的nodeInfo正常，在窗口改变后打印就是null了

public void onAccessibilityEvent(AccessibilityEvent event) {
 int eventType = event.getEventType();
        switch (eventType) {
            case AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED:
             test();
        }
}

private void test() {
 AccessibilityNodeInfo nodeInfo = getRootInActiveWindow();
        Log.d(TAG, "getRootInActiveWindow: "+nodeInfo);
        if (nodeInfo != null) {
            List<AccessibilityNodeInfo> list = nodeInfo.
                        findAccessibilityNodeInfosByText("更多");
                for (AccessibilityNodeInfo n : list) {
                    if (n.getClassName().equals("android.widget.TextView") && n.isEnabled()) {
                        AccessibilityNodeInfo parent = n.getParent();
                        parent.performAction(AccessibilityNodeInfo.ACTION_CLICK);
                    }
                }
        }
}