要研究Android中的三种动画，第一种是单个View的各种动画效果，第二种是两个Active切换时的动画效果，第三种是类似于Gif的fr a me By fr a me动画效果，其中View的各种动画包括在xml文件中定义和代码中定义两种方式。-To study the three kinds of animation in Android, the first single View, a variety of animation effects, the second switch when the two Active animation, and the third is similar to Gif fr a me By fr a me animation, in which Viewa variety of animation defined in the xml file and the code defined in two ways.