Show subfolders as real subfolders in folder list

[Ede123]

Currently all folders are shown on the same level with names like

Folder1
Folder1.Subfolder1
Folder1.Subfolder2

Actually it would be much clearer if the folder tree wouldn't be flat, e.g. subfolders where on a deeper level and reachable by tapping the containing parent folder.

Especially with many folders the current folder lists becomes almost unusable.

[dewi-ny-je]

I just connected K9 Mail to my IMAP server at home, where I stock my archived mail, and the issue mentioned is much felt. Please know that I also vote in favour of the enhancement.

[RPDiep]

I would also vote for this. It's on the wish list for quite some time: http://code.google.com/p/k9mail/issues/detail?id=17

[philipwhiuk]

If someone knows of a good library that allows:

• Visiting tree node entries
• Expanded and collapsing leaves

then this will be fairly straightforward to do - just replacing the existing list component

If not we will probably have to roll our own which is time consuming to develop.

I looked at Android Tree View for example but it doesn't seem to allow you to visit nodes which aren't leaves (e.g. there'd be no way to visit Folder1).

One other (additional?) alternative is to have a view where you have the sub folders of a folder displayed in a section above the email list as in the following ASCII art

-----               Folder 1             -------
-------------------------------------------------
------------------ Subfolder1 ------------------ 
------------------ Subfolder2 ------------------ 
------------------ Subfolder3 ------------------ 
------------------------------------------------
First email subject ----- Smith ----- 13/1/2009
Second email subject ---- Smith ----- 14/1/2009

[john-walsh]

tip:

Do use the standard 'Android Tree View', but you need to create 'self' leaves.

eg:

node: Folder1 leaf: Folder1.self node: Folder1.Subfolder1 leaf: Folder1.Subfolder1.self node: Folder1.Subfolder2 leaf: Folder1.Subfolder2.self

[Valodim]

Folders in IMAP that have subfolders can't also contain email, so android tree view should be fine. This is actually relatively simple then:

• translate folder delimiters
• replace folder list widget with tree view

Since this is just a matter of how things are displayed, I don't think we need actual database structure for subfolders to do this. If someone wants to give it a go, these can be tackled in any order :)

[dewi-ny-je]

I have IMAP folders containing also both and further subfolders. I use dovecot as server.

[cketti]

@dewi-ny-je is right. There can be folders that can't contain messages, but it's not a requirement for folders that contain subfolders.

I'd like us to store a proper tree structure in the database. In addition to that I'd like us to store the original (utf7-encoded) folder name in the database. That way we don't have to fetch the delimiter character and encode folder names all the time. It will also allow us to support folder names which aren't valid utf7 sequences.

[sebalis]

I am a beginning Android user, so please forgive me if I get terminology wrong or miss something obvious. Also, I’m using the “Material design” variant of K-9; but I believe what I’m going to describe applies in the default version too.

In my view a special tree view is not required or even beneficial for this feature (which I too very much want to be added). The existing list view has something that I will call sublists or nested lists: tapping an account brings up its folders, tapping a folder brings up its contents, and the Back button always returns to the previous view. It would be very logical if subfolders were shown using sublists too. The only question is how to show a mail folder that has both emails in it as well as subfolders below it.

There are several answers to that question, I have come up with four and I would suggest providing account options to choose between them: 1. show emails on the same level as subfolders, emails on top, 2. same as 1. but subfolders on top, 3. show subfolders plus a pseudo-subfolder on top named “(n emails)” – shown only if n>0 – so another tap is required to actually get to those emails; 4. the other way round, i.e. show emails plus a pseudo-email on top named “(n subfolders)” – again shown only if n>0 – so another tap is required to navigate into subfolders.

I think that implementing it in this way would be cleaner as it uses an interface that users are familiar with. Also, in this way subfolders would not need to be indented, so the full screen width can be used to display their names.

[sebalis]

I’m now wondering if what I am talking about is the “standard Android Tree View” that @john-walsh mentioned above, but hopefully I was still able to add something …

[dewi-ny-je]

Yes the solution suggested by @sebalis should require the least amount of work and would solve completely the issue.

[john-walsh]

Thanks @sebalis and @dewi-ny-je - yes, the solution is the same underlying mechanisum, and there are a couple of ways to deal with 'leaves' not being able to hold data (emails), so this should not be hard to implement.

[IanBod]

I too would very much welcome some form of tree structure for the folder view. The exact form doesn't matter provided subfolders can be hidden and displayed again as required.

The solution offered by @sebalis seems sensible. It could include the message count after the (sub)folder name which deals with the issue of folders containing both emails and subfolders.

[jroldroyd]

I have almost 900 folders on my IMAP server, so this would be very much appreciated. Not just in the Folders list, but also in the Choose Folder dialog when moving messages, etc.

[kikig1]

Are there any news since 2015? A Treeview for the Folders would really be very helpful ;)

[finex]

Hi, this feature request is active since 2008 (https://code.google.com/archive/p/k9mail/issues/17). Probably it will never be implemented.

[seniorm0ment]

Came here to make an issue for this, but found when searching. It's very annoying, would appreciate this to be worked on.

[weddige]

What are the current challenges for this feature? Did K-9 5.800 change the approach to solve this?

[nomis]

I think the folders would need to be displayed with two touch areas - one that opens the folder and another that either:

• Expands/collapses it in place
• Navigates into that sub-section of the folder tree, displaying only those sub-folders until the back button is used

[ASLLR]

Hi everyone,

we have an idea when this functionnality is implemented ? why is this so long ?

Thank you

[ecxod]

If someone knows of a good library that allows:

* Visiting tree node entries

* Expanded and collapsing leaves

There are several Android libraries that allow visiting tree node entries, expanding and collapsing. Some popular ones include:

• Android TreeView: This library provides a tree view widget for Android. It supports expanding and collapsing nodes, as well as customizing the appearance of the tree view.

• TreeViewList: This library provides a simple tree view for Android, with support for expanding and collapsing nodes, and might be a good fit for displaying hierarchical data such as an IMAP folder set.

• ExpandableRecyclerView: This library provides an expandable version of Android's RecyclerView widget, with support for expanding and collapsing nodes.

• TreeView: This library provides a flexible and customizable tree view for Android, with support for expanding and collapsing nodes.

Honestly, I was hoping it would be the first thing thunderbird does. No other email app shows me my list of 23487 IMAP folders as one list.

[CekLive]

Attualmente tutte le cartelle sono visualizzate sullo stesso livello con nomi come

Folder1
Folder1.Subfolder1
Folder1.Subfolder2

In realtà sarebbe molto più chiaro se l'albero delle cartelle non fosse piatto, ad esempio le sottocartelle fossero a un livello più profondo e raggiungibili toccando la cartella principale che le contiene.

Soprattutto con molte cartelle, gli elenchi delle cartelle correnti diventano quasi inutilizzabili.

I agree, K-9 will be used by Thunderbird users, so reverting some of the original Thunderbird interface would be logical

[ASLLR]

Hi everyone,

i would like to know if it's a technical issue or if you need a financial help to clos this (higly saleable) issue open since 8 years. You carry the open-source world of mobile mails clients... Please give us arguments to counter other clients by being competitive.

Thank you in advance,

Best regards.

[Dave-Rado]

According to the Roadmap, (which confusing calls itself the Thunderbird roadmap but it is really the K-9 roadmap), this should have been implemented in Q1 2023 - but it is already well into Q2, a new version of K-9 has just been released and this still hasn't been implemented. What's happening with this?

Also, it's not just making the folder structure collapsed by default and expandable that's required in order to make the folders easily navigable. It's also making the folder names display in full with wordwrapping, and taking up the full width of the screen - as already happens when you select "Manage Folders". Without this, it will still be a pain to navigate even after you've made the folders collapsed and expandable.

[HoundDogRock]

Still not implemented as of february 2024. I have a LOT of folders and sub-folders, so the application is not usable without expandable sub-folders.

[Gerben321]

It's impressive this still isn't five after 9 years. I doubt that road map is updated because there are more things on there that still haven't happened.

[ecxod]

It is related to understanding maildir format. The developer of K-9 does not understand the maildir "folder" format.

[ecxod]

Currently all folders are shown on the same level with names like

Folder1
Folder1.Subfolder1
Folder1.Subfolder2

Actually it would be much clearer if the folder tree wouldn't be flat, e.g. subfolders where on a deeper level and reachable by tapping the containing parent folder.

Especially with many folders the current folder lists becomes almost unusable.

The main Problem is that the developer does not understand the IMAP maildir folder structure

.Folder1
.Folder1.Subfolder1
.Folder1.Subfolder2

(please pay attention to the leading dot)

IMAP Servers who are set to maildir format, display folders delimited by ., in the above shown way. .Folder1.Subfolder1.SubSubFolder1. Where .XXX is a folder element. Please do not confuse the setting in 10-mail.conf called maildir_separator that is set to / with this dot. This / is just to tell the client to display the folder in a nested way.

The developer of K-9 has a different concept about this. In his world there are important folders (that contain emails about walking dog topics) and not important folders (all the rest).

have fun.