这是一个综合网上多个bmi程序最终写成的优良版bmi计算器，添加诸如字体，自定义Button类，自动控制键盘弹出隐藏，规定类型等features。-This is a advanced bmi with many new features， such as self-defined fonts, custom Button class, automatic pop-up and hidden keyboard, the provisions of type.