New Dynamic playlist pros and cons and suggestions

Sun Aug 21 17:21:35 UTC 2011

Hi Alex,
I implemented most of the new dynamic playlists.

For a start, let's state the idea behind the update of playlists.
The "old" dynamic playlists were considered complex and confusing.
Especially the percentages were seen as "at least that much" when in
fact they were "of all the songs exactly".

The "new" dynamic playlists were a further improvement over an
"in-between" design that looked a lot more like the "old" dynamic
playlists.

But now let's get into details...

> Message: 3
> Date: Sat, 20 Aug 2011 21:25:49 +0400
> From: Alexey Shildyakov <ashl1future at gmail.com>
> To: amarok-devel at kde.org
> Subject: Re: New Dynamic playlist pros and cons and suggestions
> Message-ID:
>         <CANV1RPMLqVHfK8LXyp35seEMFEe0Qa-Dw=iKgYLcKqfVYKfSjQ at mail.gmail.com>
> Content-Type: text/plain; charset=UTF-8
> 
> Dear developers,
> what do you think about my suggestions?
> 
> 2011/8/13 Alexey Shildyakov <ashl1future at gmail.com>:
> > Old Dynamic playlists:
> > Pros:
> > + Big design. All is good visible.
> > + No addition windows. Change the values immediately.
> > + More tradition KDE design
> > Cons:
> > - No limit to Proportion. Proportion summary might be greater than
> 100%.
> > - No sophisticated conditions.
> >

Yes. You also didn't understand the old playlists. Don't feel bad. I had
to look at the code to understand what the percentages really mean.
Also the playlists could be quite sopisticated if you understood it.

> > New Dynamic playlists:
> > Pros:
> > + Sophisticated conditions - almost you want.
> > + Limit to Proportion. The sum of proportions is always 100%
> > Cons:
> > - Addition windows to edit values
> > - A little design. It's difficult to look at this and understand the
> > percentages.
> > - No percentage is shown.
> > - Unusable automatic change of proportion.
> >

The "list view" was a further step away from the old design.
It became clear that unless there is a clear textual representation
about the biases they would not be understood by the user.
Complex widgets were not good enough.

Also I left out the display of actual percentage values which was
requested by several developers.

The "unusable" change of porportion was just a first implementation. I
see the drawbacks but I also see more pressing issues with Amarok, like
multiple genres or cuesheet support, both of which have an insane count
of votes.

> > Thinking:
> > Lets think about new dynamic playlist disadvatages.
> > 1. Addition windows to edit values
> > The reason it was implemented that DP become more configurable. So
> it is normal.
> > 2. A little design.
> > Design is for you opinion, but it's really difficult for
> understanding.
> > 3. No percentage for proportion is shown. It's difficult to look at
> > little design and understand the percentages.
> > It's bad because there is no way to understand numerical values of
> > proportions. The values should be shown in normal view and in window
> > while changing.
> > 4. Unusable automatic change of proportion.
> > The problem the user don't understand how another proportions will
> be
> > changed when he change one. And for me it problem when I add new
> > proportion or change one - then I must change percentage for all
> > proportions. It's difficult and spend much time.
> >
> > I suggest the user non-editable bar which show the deficiency and
> > excess of summary proportions percentage. The bar width is the same
> as
> > the width of another real editable bars but the virtual length is
> > depend on number of proportions in the same level. For example if 3
> > proportions are presetned, the minumum is -300% and maximum is
> +100%.
> > If every proportion has 100%, then ?this bar has -300%. If every
> > proportion has 0%, this bar has 100%. The bar have the middle value
> > 0%. So think this bar should be called "Proportion deficiency".
> > This bar must be presented in every where proportion might be.
> > The slider is automatically moves inside the bar and represent
> > deficiency or excess with showed +-percentage label. So, the user
> can
> > choose any value for any proportion when user add new or change one
> > value as he want to be. The button OK in window should be disabled
> if
> > this bar has non zero value. So, the user must manually change the
> > proportions that sum of them will be 100% so this bar has 0% and the
> > slider be in the middle.
> > The helpers is editable proportion percentage textbox and button
> "MAX"
> > that add maximum possible deficiency to the current proportion the
> sum
> > of proportions to be 100%. Usually user want to decrease proportions
> > manually but may want to fill remaining deficiency to up to 100%.

Actually, I can't think of any application that has a user interface
like this.
Disallowing the user to close a dialog? Hmmm.

Anyway, if you think that this is much better than the current
implementation, feel free to send the patch to the review board and we
will try it out.
I might be wrong (or didn't quite understand your proposal) and this
really works in practice.

> >
> > Suggestions to improve usability:
> > - Use in edit view (in window) big design as in old dynamic
> playlist.

No. We already had that.
Please see the disasterous review for my original review request here:
https://git.reviewboard.kde.org/r/100630/

> > - Show percentage in normal view. The possible place is before the
> > left of labels and right of bar for each proportion.

Showing percentages instead of the small bars might really improve the
clarity.

> > - Show percentage in editing view in window at the right of bar as
> in
> > old dynamic playlists.

Can't see the benefit of that and showing actual percentages does not
really help here.
A pie chart might be cool.

> > - Provide functionality when user can change the proportion by
> writing
> > numeric value in textbox. Think the textbox should be the textbox
> > described in previous paragraph.

Normal sliders don't have that. Also I don't care if it's 50 or 51%, so
I don't see a benefit.

> > - Add button "max" at the right of editable percentage textbox to
> get
> > rid of proportions deficient.
> >
> > Why this is bug?
> > and not wish? The reason I set it to Minor bug is that the situation
> > was bad yesterday, is bad today and might be bad in the future. It's
> > difficult to use current Dynamic playlist. Think, this is good place
> > to discussing about Dynamic playlists and solve the problem once and
> > for all and won't change it from one to another releases.
> >
> > Dear developers and users, what do you think about these
> suggestions?
> >
> > --
> > Best Regards, Shildyakov Alexey Vladimirovich
> >

I am wondering about the "once and for all".
I was working about dynamic playlists for quite some time and the
current design is the best compromise between functionality and clarity
that I came up with.

I got some complaints in the beginning but I am still convinced that
it's a step in the right direction. (By the way, if I would have given
in about the complaints you would probably not have a part-bias to play
around with)

Anyway, we are pretty open about the design. Just submit your patch or
convince an  Amarok developer that this is worth his/her time.

Cheers,
Ralf