简单 bannerView 的demo 直接拷贝文件夹bannerView 到项目中， xib 中新建一个view ，设置好约束，custom Class设为 BannerView 即可初始化完成-Simple demo bannerView direct copy folder bannerView to the project, the new Xib in a view, set a good constraint, Class custom is set to BannerView ca