This post is a Call To Action™ for those with the ability to set up a Plasma development environment and an interest in code hygiene. Plasma 6 development is in full swing, and we have an opportunity to make a difference by doing some relatively easy code porting. Read on if this intrigues you!
History
First, some background: For many years, Plasma has maintained forks of various Kirigami bits whose only purpose in life was to get colors from the active Plasma theme, rather than the systemwide color scheme. For example, Heading exists in both Kirigami, and also PlasmaExtras; they both do the same thing and are implemented the same way under the hood, but the PlasmaExtras version gets its colors from the active Plasma theme. If it didn’t, then when you used the Breeze Twilight theme, the text colors on your dark Plasma widgets would come from the systemwide light color scheme, be inappropriately dark, and you wouldn’t be able to see them.
Maintaining forks with minimal differences worked but wasn’t ideal, as they could–and sometimes did–drift subtly out of sync and cause maintenance headaches. It would be better if we could use the Kirigami versions in Plasma and have them substitute Plasma colors automatically. As of today, core Plasma developer Marco Martin has done just that for Plasma 6 with two patches!
Ultimately this will let us get rid of the forks, at least for components that don’t do any SVG styling (that’s planned too, but not ready yet).
How you can help
So with that out of the way, here’s how you can help: throughout Plasma (i.e., all repos in the Plasma group), submit merge requests with the following changes:
| Replace this… | …with this: |
|---|---|
PlasmaExtras.Heading | Kirigami.Heading (Example merge request) |
PlasmaCore.Theme.smallestFont | Kirigami.Theme.smallFont |
PlasmaCore.Theme.NormalColorGroup | Kirigami.Theme.Window |
PlasmaCore.Theme.mSize([default font]).height | Kirigami.Units.gridUnit |
PlasmaCore.Theme.[anything else] | Kirigami.Theme.[the same thing] |
PlasmaCore.ColorScope.colorGroup | Kirigami.Theme.colorSet |
PlasmaCore.ColorScope.inherit | Kirigami.Theme.inherit |
PlasmaCore.Units.largeSpacing | Kirigami.Units.gridUnit (due to a bug where PlasmaCore largeSpacing was too big; we need to change it to a Kirigami gridUnit to keep the expected sizing) |
PlasmaCore.Units.devicePixelRatio | 1 |
PlasmaCore.Units.roundtoIconSize([height of the default font]) | Kirigami.Units.iconSizes.sizeForLabels |
PlasmaCore.Units.roundtoIconSize([some integer value]) | Kirigami.Units.iconSizes.roundedIconSize([the same thing]) |
PlasmaCore.Units.[anything else] | Kirigami.Units.[the same thing] |
Quirks to be aware of
Make sure your master branch is up to date before you start looking at code, and also check to see if anyone else has already submitted a merge request. You don’t want to do work for nothing!
If any file with such changes made to it doesn’t already have a line near the top that says import org.kde.kirigami 2.20 as Kirigami, add it We can’t use Kirigami stuff without importing Kirigami!
If as a result of these changes to any particular file, nothing in it is still using PlasmaExtras or PlasmaCore anymore, you can also remove those import lines at the top.
Testing
Make sure to test your changes! Apply the changes to your Plasma 6 development build and restart. Then use the Breeze Light color scheme and the Breeze Dark Plasma theme and make sure all changed text is still readable, that anything using a small font size is still doing it correctly, that colors in general look correct, and that spacings and units look correct. You want to see no visual changes at all.
In the future
Later, we’ll also be able to port forked components that internally use Plasma-specific SVG theming. For example, PlasmaExtras.PlaceholderMessage is identical to Kirigami.PlaceholderMessage but it internally contains Plasma-specific labels and buttons that use Plasma SVG theming, rather than theming from the app style. We’re planning some more code wizardry so that the Kirigami versions of these components can dynamically substitute the internal Plasma SVG themed variants when run in Plasma. This isn’t ready yet, but when it is, I’ll announce another porting opportunity for folks who enjoyed (or missed out on) this one!
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