hi @sheaf:matrix.org ! I am not sure why that wouldn't work. Just to be clear: you only need the latest
haskell-gi and haskell-gi-base from github, the bindings themselves (the gi-* packages) in hackage should be OK. Just make sure that they are regenerated (removing your .dist-newstyle should do the job).
Please make sure that you use commit haskell-gi/haskell-gi@04bf16a, I have changed some things there
ah, I didn't realise I only needed to change haskell-gi and haskell-gi base, I'm trying that now and will let you know, thanks
However, I am a bit stumped how to configure / setup my project to use GTK4 with stack
I tried adding "gi-gtk-4.04" to the "extra-deps" property of the "stack.yaml" file, but then I run into trouble with mismatched dependencies
Is there an example project or howto how to use GTK4 + haskell-gi and stack?
Is there an example project or howto how to use GTK4 + haskell-gi and stack?
Unfortunately nothing that I am aware of. It should be possible to do by adding enough packages to your stack.yaml, there is some relevant discussion in haskell-gi/haskell-gi#339
Nevertheless, if you have a chance I highly recommend trying
cabal before going into that. At least for building haskell-gi generated bindings it is often easier with cabal.
How would you translate
new Gtk.Window [ On #destroy Gtk.mainQuit ]
`to code that doesn't use labels?
Also: I'm trying out the WebKit example, and the text is much smaller than compared to other browsers
Is it supposed to be like this? Is it perhaps because of NixOS?
I also see the text slightly small here. It is not intentional, it seems to be due to defaults in webkit. You can check by opening "Epiphany", Gnome's web browser, which is also based on WebKit.
At least in my computer both epiphany and the webkit example display text at the same size.
If you figure out how to make the default a bit larger I would gladly welcome a pull request :)
@garetxe: Thanks for confirming my suspicion, Epiphany shows much larger text (that is within the normal range, albeit a bit smaller than what Firefox displays). What I get on https://haskell.org is text so small that it's hard to even read. It's likely a problem with my nix derivation for it then.
Hi! I'm currently trying to combine some concepts of gi-gtk-declarative with the reflex-gi-gtk library, but i've hit a (seeming) dead end for me.
I want to write an equivalent of https://hackage.haskell.org/package/gi-gtk-declarative-0.7.0/docs/src/GI.Gtk.Declarative.Bin.html#bin for a reflex-based application
But even though gtk-declarative is able to use
new (from GI.Gtk) without specifying the bins type, i don't seem to be able to
I can't even write a top-level
myNew = new (with GI.Gtk in scope)
1 reply
• Overlapping instances for GI.Constructible a0 tag0
arising from a use of ‘GI.new’
Matching instances:
instance [overlappable] (GI.GObject a, tag ~ 'GI.AttrConstruct) =>
GI.Constructible a tag
-- Defined in ‘Data.GI.Base.Constructible’
instance (tag ~ 'GI.AttrSet) =>
GI.Constructible G.AccelGroupEntry tag
-- Defined in ‘GI.Gtk.Structs.AccelGroupEntry’
instance (tag ~ 'GI.AttrSet) => GI.Constructible G.AccelKey tag
-- Defined in ‘GI.Gtk.Structs.AccelKey’
...plus 35 others
...plus 95 instances involving out-of-scope types
(use -fprint-potential-instances to see them all)
(The choice depends on the instantiation of ‘a0, tag0’
To pick the first instance above, use IncoherentInstances
when compiling the other instance declarations)
• In the expression: GI.new
In an equation for ‘myNew’: myNew = GI.new
|
97 | myNew = G.new
| ^^^^^
in this case GI is Data.GI.Base.ShortPrelude and G is GI.GTK
nvm, i haven't yet found a real solution, but i think i'm able to figure it out myself
well, now I've found a real solution (thanks to https://lexi-lambda.github.io/blog/2021/03/25/an-introduction-to-typeclass-metaprogramming/)
:]
Please don't hesitate to ask if you run into other issues, I'll try to keep a closer eye on this
I'm getting a SIGSEGV with gi-gtk. The backtrace is at https://gist.github.com/miguel-negrao/ba7990d368bd7c886ecd2fdef2ef5842
To check that I'm not doing anything obviously wrong, I'm creating a widget with new and adding it to a container with
boxPackStart box widget expand fill padding
I'm then destroying the widget with
widgetDestroy which appears to trigger the crash.
And another question: how would I replicate https://hackage.haskell.org/package/gi-gtk-4.0.5/docs/GI-Gtk-Objects-Scale.html#v:scaleNew with https://hackage.haskell.org/package/haskell-gi-base-0.26.0/docs/Data-GI-Base-Constructible.html#v:new , since it has some additional parameters ?
I'm then destroying the widget with
widgetDestroywhich appears to trigger the crash.
This sounds a bit like you are double freeing. Is it necessary to call widgetDestroy in your code? Every widget in Gtk is reference counted. In particular if you create a widget and add it to a box then it will have a refcount of 2: Haskell keeps one (which it will drop once the Haskell object is garbage collected) and the container keeps another.
So basically you never need to care about freeing things manually.
(By the way, when debugging crashes it is useful to run with the following environment vars set:
export G_SLICE="debug-blocks"
export MALLOC_CHECK_=2
export MALLOC_PERTURB_=$(($RANDOM % 255 + 1))
export HASKELL_GI_DEBUG_MEM=1)
And another question: how would I replicate https://hackage.haskell.org/package/gi-gtk-4.0.5/docs/GI-Gtk-Objects-Scale.html#v:scaleNew with https://hackage.haskell.org/package/haskell-gi-base-0.26.0/docs/Data-GI-Base-Constructible.html#v:new , since it has some additional parameters ?
In general it should be perfectly fine to call scaleNew, but in this case it might be possible to make it work with new too. Have you tried setting the orientation and adjustment attributes? Something like
scale <- new Gtk.Scale [#orientation := ..., #adjustment := ...]
This is happening in the context of code, where I'm trying to have a more declarative approach to adding and removing widgets to a container. I use HList since widgets can have different types. The "map" type functions for hlist are these:
data HPackBox = HPackBox
instance (IsDescendantOf Box a, IsDescendantOf Widget b,
Constructible b tag, MonadIO m, GObject a, GObject b,
input ~ ((a, Bool, Bool, Word32), (ManagedPtr b -> b, [AttrOp b tag])), output ~ m b) =>
ApplyAB HPackBox input output where
applyAB _ ((box, expand, fill, padding), (ctr, attrs)) = do
widget <- new ctr attrs
boxPackStart box widget expand fill padding
return widget
data HDestroyWidget = HDestroyWidget
instance (IsWidget o) => ApplyAB HDestroyWidget o (IO ()) where
applyAB _ widget = widgetDestroy widget