bugly上报了几个snake的奔溃，帮忙优化一下

[zfnian]

#7024 java.lang.NullPointerException
Attempt to invoke virtual method 'int android.view.View.getImportantForAccessibility()' on a null object reference
com.youngfeng.snake.view.SnakeHackLayout.onLayout(SnakeHackLayout.java:268)

#28304 java.lang.IndexOutOfBoundsException
Index: 2, Size: 0
com.youngfeng.snake.view.SnakeHackLayout.dispatchTouchEvent(SnakeHackLayout.java:4)

[zfnian]

第一个空指针，可以做个判空规避一下；
第二个数组越界不知道怎么解决，从dispatchTouchEvent(SnakeHackLayout.java:4)里引起，以下是全部推栈：

java.lang.IndexOutOfBoundsException
Index: 1, Size: 0
1 java.util.ArrayList.get(ArrayList.java:437)
2 android.view.ViewGroup.getAndVerifyPreorderedView(ViewGroup.java:3568)
3 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2583)
4 android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2988)
5 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2613)
6 android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2988)
7 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2613)
8 android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2988)
9 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2613)
10 android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2988)
11 android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:2613)
12 com.youngfeng.snake.view.SnakeHackLayout.dispatchTouchEvent(SnakeHackLayout.java:4)
13 android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2988)

[zfnian]

上述2个问题如果解决了，请发邮件给我 ：582021237@qq.com