July 2021 - xmonad - Haskell.org

Is there a way to reparent a window manually?
by Platon Pronko 26 Jul '21

26 Jul '21

Hi! I'm trying to run Unity Editor under XMonad. Unfortunately I'm having issues - sub-windows of the main window are not redrawn properly, resulting in ugly mess (previously-opened menu lists do not disappear, etc). It seems that this could be happening due to XMonad being non-reparenting (I ran the same app under XFCE, and it seems to work okay). Is there a way to reparent a window manually? I tried creating a new X window via Python and Xlib, as in this example: https://rosettacode.org/wiki/Window_creation/X11#Python and then reparenting the window to it via `xdotool windowreparent` and subsequently `xdotool windowmap` plus `xdotool windowsize`. It partially worked - the app window correctly resized to fill the parent window, seems to be reacting to mouse move and mouse scroll events (interface elements are highlighted), reacts to keyboard events, but completely ignores mouse button events (clicks/drags). I'm attaching create_window.py script I used to create the window. Any idea about what am I missing? Maybe my event masks are wrong? Best regards, Platon Pronko

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tweaking xmonad into a reparenting window manager
by Platon Pronko 25 Jul '21

25 Jul '21

Hi! Is there some fundamental reason why Xmonad is non-reparenting? My current (naive) understanding is that Xmonad does not reparent the windows simply as a small optimization (why create a second window if you can live with one window just fine). If that's the case, then adding a tweak that allows Xmonad to do reparenting should be doable. However I understand that it will be non-trivial undertaking, so I wanted advice of more experienced developers before I sink in a lot of time to find out that this is fundamentally impossible for some reason. Best regards, Platon Pronko

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Managing Multiple Displays
by Eyal Erez 21 Jul '21

21 Jul '21

Hi, I often use multiple displays. Here are some configurations that I've used with my laptop: 1. Laptop monitor only 2. External monitor only (laptop lid closed) 3. External and laptop monitor at the same time. 4. Two external monitors (laptop lid closed). In order to show display correctly (which monitor is to the right/left of which and which is on/off) and shift trayer around to the right monitor and position, I've written a script that parses the output of xrandr, figures out if the laptop lid is open or not, then calls xrandr again to activate the right monitors and kills and relaunches trayer and places it in the correct position. I launch this script from a keybinding configured in xmonad.hs. This works, however, it has several disadvantages. The first is that adding a new configuration is a bit tedious -- this doesn't happen very often so it's not a huge deal. The other is that I can only activate the script if my screen is unlocked. This means that if my laptop is suspended and I want to disconnect the external monitor and put it in my bag for later use, I need to first wake it up, unlock it, launch the script to turn the laptop monitor on, and then put it away. Otherwise, I'll be staring at a blank screen when I turn it on and have to guess what to press to unlock and use the script. I was wondering how others deal with this challenge? Are there other, more well-built tools, than the script I have to do this more robustly and automatically? Thank you, -- There are 10 types of people, those who know binary and those who don't.

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Re: [xmonad] question about code in XMonad.Actions.GridSelect
by Platon Pronko 15 Jul '21

15 Jul '21

Ah, yes, stack recommended to add it to extra deps. But I got scared of the long "sha256:30d72d..." string, wanted to keep it much simpler since I'm new here. I think if we want to update random then it would make sense to do it in separate PR - I can do it if you'd like. Best regards, Platon Pronko On 2021-07-15 13:20, Solid wrote: > On Thu, Jul 15 2021 11:34, Platon Pronko wrote: >> I've decided to just go with randomR, simpler and guaranteed to >> work. Here's the PR: > > You're probably right; though the whole Random class is (soft) > deprecated. Quoting from the docs[1] > >> Random exists primarily for backwards compatibility with version 1.1 >> of this library. In new code, use the better specified Uniform and >> UniformRange instead. > >> P.S. I don't see an attachment in your email. But if there was simply an addition of >> "random >= 1.2" to build-depends (library and tests), then I've already tried and >> stack gave me lots of new errors (apparently the ghc snapshot it downloaded >> already includes random-1.1?). > > Ah, silly me; sorry. Should be attached now. If it's not on stackage > yet, you also have to add the version to the extra-deps. > > [1]: https://hackage.haskell.org/package/random-1.2.0/docs/System-Random.html#v:… >

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Re: [xmonad] question about code in XMonad.Actions.GridSelect
by Platon Pronko 15 Jul '21

15 Jul '21

I've decided to just go with randomR, simpler and guaranteed to work. Here's the PR: https://github.com/xmonad/xmonad-contrib/pull/573 P.S. I don't see an attachment in your email. But if there was simply an addition of "random >= 1.2" to build-depends (library and tests), then I've already tried and stack gave me lots of new errors (apparently the ghc snapshot it downloaded already includes random-1.1?). Best regards, Platon Pronko On 2021-07-15 11:27, Solid wrote: > On Thu, Jul 15 2021 10:31, Platon Pronko wrote: >> Should I use randomR instead? Alternatively, how can I specify that a >> newer version of random should be used? > > AFAIK you just have to specify that in the cabal file. I've attached a > diff that should probably work. > > The main thing is to test whether this works with all of the GHC > versions that we support (which is back to 8.4.4 right now). If that's > the case then I have no objections to raising the version bounds for > random—especially for random actually; the library has gotten a dearly > needed overhaul with 1.2. >

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Re: [xmonad] question about code in XMonad.Actions.GridSelect
by Platon Pronko 15 Jul '21

15 Jul '21

Hi! I'm working on a PR right now. I've implemented the fix already, but I have trouble with tests - `stack test` uses random-1.1, and uniformR is not found there. Should I use randomR instead? Alternatively, how can I specify that a newer version of random should be used? Best regards, Platon Pronko On 2021-07-15 10:21, Solid wrote: > Hi, > > On Thu, Jul 15 2021 08:44, Platon Pronko wrote: >> Looks like it is supposed to simply generate a Double number between 0 >> and 1 - why such complicated approach was used instead of `uniformR` >> from System.Random? > > this was implemented all the way back in ~2008 it seems; barely anyone > from that era is still around, so I doubt you'll get a satisfying answer > to _why_ :) > > The `uniformR` function didn't exist back then, but `randomR` certainly > did; I don't quite know why it was implemented in this convoluted way. > I would definitely welcome a pr that fixes this, if you're so inclined. >

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question about code in XMonad.Actions.GridSelect
by Platon Pronko 15 Jul '21

15 Jul '21

Hi! I'm looking at XMonad.Actions.GridSelect code (wanted to fix compilation warnings), and I stumbled over the following function. -- | Generates a Double from a string, trying to -- achieve a random distribution. -- We create a random seed from the sum of all characters -- in the string, and use it to generate a ratio between 0 and 1 stringToRatio :: String -> Double stringToRatio "" = 0 stringToRatio s = let gen = mkStdGen $ sum $ map fromEnum s range = (\(a, b) -> b - a) $ genRange gen randomInt = foldr1 combine $ replicate 20 next combine f1 f2 g = let (_, g') = f1 g in f2 g' in fi (fst $ randomInt gen) / fi range Looks like it is supposed to simply generate a Double number between 0 and 1 - why such complicated approach was used instead of `uniformR` from System.Random? (also it seems that it is buggy and returns huge negative numbers, because `range = (\(a, b) -> b - a) $ genRange gen` is always -1. Best regards, Platon Pronko

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Full-screen messes up tabs on google chrome
by Eyal Erez 04 Jul '21

04 Jul '21

Hi, I've started encountering a strange issue with xmonad and google chrome. After a full-screen chrome (e.g. by watching a youtube video and hitting "f"), the top part of chrome goes behind xmobar. If I make a layout change or open another window or app then it pops back into place, but this is a little bit annoying. I have some screenshots to try and illustrate this issue: During full-screen: https://ibb.co/z4hjC31 Before full-screen: https://ibb.co/TPPgRVS After full-screen: https://ibb.co/Y2vK1Xq Is it my setup that's the problem? Is there any way to fix it? My config file as available here: https://controlc.com/09924e80 Thank you -- There are 10 types of people, those who know binary and those who don't.

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