自己写的一个，鼠标进入区域，离开区域后按钮，改变贴图的控件，也可稍加改动，做三态的贴图按钮-himself wrote a click of the mouse to enter and leave the region after the button and change the map controls can also tamper do three state map button

简单的图片三态按钮实现。虽然简单了点，一看就懂，但是有些时候可能会用到-Simple picture tristate button achieved. Understand at a glance