看这样一张图 我们首先需要绘制这样一个View继承系统自带的EditText
1. 绘制外围Rect
2. 绘制分割线
3. 绘制圆点密码
大家看到边框、分割线、圆点密码的颜色、大小、都是通过自定义属性而获得，
在写布局文件都可以自定义，从而实现不同的效果的支付密码输入框
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Copyright 2018 StevenYan88
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