实现了以下一些方便的操作：

1.连续输入；

2.连续删除；

3.任意位置插入；

4.自适应大小变化。

5.正则匹配，每个值不大于255。设置IP值时，有正则进行验证是否是IP格式。

实现方法，使用一个大的QLineEdit嵌套四个小的QLineEdit，中间的点是使用paintEvent画出来的。操作是使用eventFilter来进行分发实现的。-

Here are some easy to achieve the following:

1. Continuous input

2. Continuous deleted

3. insert anywhere

4. Adaptive size variations.

5. The regular match, each value is not more than 255. When you set the value of IP, there is a regular to verify whether the IP format.

Implementation, use a large QLineEdit nest four small QLineEdit, the intermediate point is the use of paintEvent drawn. Operation using eventFilter for distribution achieved.