说明: 一个完整的Android项目,首先进入界面输入账户密码进行登陆,若登陆账号没注册过则先进行保存,并提示保存成功否则提示登陆成功。(A complete Android project, first enter the interface to enter the account password for login, if the login account has not been registered, save it first, and prompt the successful save or prompt the successful login.)