Android在外部修改了工程名文件夹名称，报错

 FATAL EXCEPTION: main
                                                 Process: com.rhitland.temphosp, PID: 1842

                                                 java.lang.RuntimeException: Unable to instantiate application com.rhitland.temphosp.App: java.lang.ClassNotFoundException: Didn't find class "com.rhitland.temp.App" on path: DexPathList[[zip file "/data/app/com.rhitland.temphosp-2/base.apk"],nativeLibraryDirectories=[/data/app/com.rhitland.temphosp-2/lib/arm, /vendor/lib, /system/lib]]

解决：

Build - Clean Project

Build - Rebuild Project

重新运行安装。