General assistance in Google Apps scripting - google-apps-script

Question

OK, I'm tired of searching for specific questions to help with a project, finding answers, changing my implementation which just adds more questions, realizing there's a better way to do things, etc. So allow me to ask for general assistance, I will then do my best to research how to do it and ask further questions if needed.
I'm writing a script to be used as a Gadget in a Google Site page
(I'm more than willing to share this if anyone wants to take a look
at it); right now I'm doing this just for me, but I want to write
this to be easily used by others.
This will list all user's Google Docs in a specified folder; when
selecting the document from the list, the contents will be displayed
for editing in another field.
The user will be able to define certain lines, starting wit a period,
to "mark" as chords that can be automatically transposed with the
push of a button; that is to say, the user clicks a button and all
A's go to A#, B to C, C to C# and so on, but only on the specified
"Chord" lines.
The user can then save this document back to the Google Docs for
printing if needed.
I've got the layout mostly. Some problems I'm coming across:
Doing a .find apparently finds all documents that have the given string in the name and
the contents. The fix would be to put the document IDs in a Hidden, but it doesn't seem
that a List returns the numbered item you clicked on, so how can I also get the ID
that's stored somewhere else?
I'd like the TextArea to be rich text for bolding and what-not; does
Google Apps have a text editor (it'd be awesome if I could just put
the Google Docs editor in a panel)? RichTextArea has been
deprecated, is there a replacement?
To do the transposing, I was planning on just putting every character
of the text area into an array, stepping through the array, when it
sees a "\n" followed by a "." to flip a var "on", then changing any
following characters, then if it sees another "\n" to turn the var
"off"; is there a better way to do this?
Or, is there way to add a script to a Google Document that would do
the transposing (I know you can do macros for spreadsheets, but there
doesn't really seem to be an equivalent for documents)? That way I can
just give out this macro and tell people to use on their existing document.

Answer 1

Since you asked, yes, separate questions would be appropriate, because the combination of questions is very specialized, while the individual problems might be more general, and of use to more people. But let me take a stab at it anyway...
[With the result of find()]... how can I also get the ID that's stored somewhere else?
DocsList.find() returns a list of File objects. Class File has a getId() method that returns the document ID you are used to seeing in Google Drive. To get the IDs of all your files:
var files = DocsList.getAllFiles();
for (var i in files) {
Logger.log(files[i].getId());
}
You should also look at DocsListDialog for creating a file picker that works on Google Drive.
RichTextArea has been deprecated, is there a replacement?
No, not in apps-script. You've just got TextArea. However, you may be able to embed a third-party rich text editor in your UI.
To do the transposing, ... is there a better way to do this?
Change the TextArea.value into an array of lines, then manipulate those, without needing to manage an on/off state. See How do I get information out of TextArea in Google App Script on the button click? and Javascript: Convert textarea into an array.
// aTextArea contains user's input. Probably a Johnny Cash song.
var inputText = e.parameter.aTextArea;
var inputLines = inputText.split('\n');
for (var i in inputLines) {
if (inputLines[i].charAt(0) == '.') {
// Transpose
}
}
// Put lines back together, if you wish
var outputText = inputLines.join('\n');
..is there way to add a script to a Google Document that would do the transposing...
Yes (capability extended to Docs and Forms since question was originally asked). No, Spreadsheets are the only document type that can be a container for scripts at this time.
Alternatively, you could employ a stand-alone script to operate directly on Docs! Perhaps with a script deployed as a Web App that lets users pick the target music to transpose from documents on their Google Drive, and that then writes a new copy of the document, transposed?