Reserved Characters in Folder Names

This is a quick repeatable bug report that affects SAB and RAB, maybe the other builders.
In a course this week, people created a test project called “Luke and Acts”. Some people, trying to save character space, called the project “Luke & Acts”. Everyone was able to build the app, but those with the ampersand would get “no book found” when they loaded the app. I remembered that “&” is a reserved character in Android path names, and this was now encoded in the folder structure of the project. We worked around the error by starting a fresh project without the &, because changing the app name in SAB doesn’t rename the folder.

It’s dangerous to create folder names based on user input without some validation. The App builders should probably not allow ANY reserved characters from Android/Win/iOS/Mac to be used in file and folder names, but apostrophe and & are the most likely candidates that people will use.

Here’s a good list of things that should be avoided.

Do not use any of these common illegal characters or symbols in your filenames or folders:

# pound

% percent

& ampersand

{ left curly bracket

} right curly bracket

\ back slash

< left angle bracket

> right angle bracket

* asterisk

? question mark

/ forward slash

$ dollar sign

! exclamation point

' single quotes

" double quotes

: colon

@ at sign

+ plus sign

` backtick

| pipe

= eq

Create an App with “&” in the project name. Build and install the app on Android. The app will open and error as it can’t find the books.


Thanks for this @Matthew_Lee
I just experienced this, this week, trying to rename a project ! project_name in an attempt to force it to the top of a list of projects.

The project folder, settings file and sub-folder were renamed, but SAB had to be force stopped.

I just renamed them back in explorer and learnt my lesson.

Yes, in addition to the folder and .appdef names, SAB keeps a manifest of all its files including the project name in the full path, so even with a manual rename, the app will be missing files.

Underscore should be acceptable in an initial project name, but maybe not at the beginning of a file or folder since that sometimes means something.