用新的Android SDK 29编译的时候,Studio提示Environment.getExternalStorageDirectory()过时了,要用Context#getExternalFilesDir代替,Android Q以后Environment.getExternalStorageDirectory()返回的路径可能无法直接访问,所以改成了Context#getExternalFilesDir用新的Android SDK 29编译的时候,Studio提示Environment.getE