如何获取toast.maketext中显示的文件名

I made some experiments with the gallery to learn how to use it and I need to understand how I can get the filename showed by the Toast.maketext instead of the position number I tried to use getString but the emulator stops after loading the app. Here's my code maybe someone got the same problem and can suggest me a new way to get the part of the file after R.drawable.I made some experiments with the gallery to lea