[Kirigami] Support for stacked page rows (a proposal)

[Aleix Pol]

On Sun, Jun 18, 2017 at 11:39 PM,  <kelvin.atomblender at riseup.net> wrote:
> Hi,
> I'm developing my application using Kirigami 2 and I really like the
> PageRow component which allows simple navigation between pages and makes
> it easy to target phones and tablets with one code base. However I find
> it rather limiting to have only one page row per application available.
>
> For example if I have a few pages currently shown in the page row and I
> want to show a page from completely different context e.g. settings I
> have only two choices:
> 1. show the page next to other pages - I think this is not a good idea
> because the page belongs to entirely different context so I would like
> it separated from other pages. Also I might not want to allow
> interacting with other pages while I'm browsing a settings page
> 2. clean up the page row and show settings page - if I'm not mistaken
> this is how Discover works. However when I clean the page row I throw
> away its current state e.g. current page info, scroll level in each page
> and any per page data e.g. selected items.
>
> So I was experimenting a bit with Kirigami code to try to overcome this
> limitation. With really small code modifications I've designed this:
> 1. I introduced the concept of Activity, which is a basic visual
> container. It can contain one page row or many swappable page rows.
> 2. I introduced ActivityStack which stacks the activites in the QQC2
> StackView. ApplicationWindow.activityStack property replaced
> ApplicationWindow.pageStack property as a main visual container.
> 3. I patched a few components (Headers, Drawers, Pages) to reference
> ApplicationWindow.activityStack.currentActivity.pageRow instead of
> ApplicationWindow.pageStack
>
> ...and it mostly works:)
>
> I got the idea of Activity from Android:
> https://developer.android.com/guide/components/activities/intro-activities.html
> https://developer.android.com/guide/components/activities/activity-lifecycle.html
> https://developer.android.com/guide/components/fragments.html
>
> You can see the effects in the attached archive which contains 3
> folders:
> 1. kirigami-new: source of 3 new and ~10 patched components of Kirigami
> 2. kirigami-simplest: example showing how simple it is to use
> kirigami-new with one activity and one page row
> 3. kirigami-rssfeeds: example with two activites: the default
> BrowserActivity shows fake rss feeds. When the user wants to see
> settings the SettingsActivity is pushed on the ActivityStack and it
> covers BrowserActivity. Both activities have their own page rows and
> they set their preferred application header style. When the user exits
> settings the control goes back to BrowserActivity and its state is of
> course the same as when the user left the activity (well, almost: for
> unknown reason scroll positions slightly differs).
>
> I hope this idea will somehow be introduced into Kirigami, if not the
> way I proposed (activities) then some other. It doesn't change
> Kirigami's design principles but rather extends it and makes it more
> flexible.
>
> Regards,
> K.

Sounds interesting! I would indeed appreciate some flexibility there.

As marco pointed out, having good API for this is really important.
Maybe it's something we can discuss over phabricator?

Aleix