Sway

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Revision as of 15:42, 25 October 2020 by Lahwaacz (talk | contribs) (move the note out of the introduction, link to the sway wiki for details)

sway is a compositor for Wayland designed to be fully compatible with i3. According to the official website:

Sway is a tiling Wayland compositor and a drop-in replacement for the i3 window manager for X11. It works with your existing i3 configuration and supports most of i3's features, plus a few extras.

Installation

sway can be installed with the sway package. The development version can be installed using wlroots-gitAUR and sway-gitAUR. It's advisable to always update wlroots when you update sway, due to tight dependencies.

Note: All proprietary graphics drivers are not supported, including NVIDIA.

You may also install swaylock and swayidle to lock your screen and set up an idle manager.

The default application launcher is dmenu and the default terminal emulator is alacritty. Before starting sway it is advisable to either install them or set a new launcher and terminal in the configuration.

Starting

Manually

To start Sway, simply type sway in the Linux console.

From a display manager

Note: Sway does not support display managers officially.[1]

The sway session is located at /usr/share/wayland-sessions/sway.desktop. It is automatically recognized by modern display managers like GDM and SDDM.

It is also possible to start sway as a systemd user service through the display manager.

Also you can use text-based session manager, see Display manager#Console.

Configuration

If you already use i3, then copy your i3 configuration to ~/.config/sway/config and it should work out of the box. Otherwise, copy the sample configuration file to ~/.config/sway/config. It is located at /etc/sway/config, unless the DFALLBACK_CONFIG_DIR flag has been set. See sway(5) for information on the configuration.

Keymap

By default, sway starts with the US QWERTY keymap. To configure per-input:

~/.config/sway/config
input * {
    xkb_layout "us,de,ru"
    xkb_variant "colemak,,typewriter"
    xkb_options "grp:win_space_toggle"
}

input <identifier> xkb_model "pc101"

More details are available in xkeyboard-config(7) and sway-input(5).

The keymap can also be configured using environment variables (XKB_DEFAULT_LAYOUT, XKB_DEFAULT_VARIANT, etc.) when starting sway, with config options taking precedence over environment variables.

Typematic delay and rate

To change typematic delay and rate, you can add the following lines to your input section:

~/.config/sway/config
input <identifier> repeat_delay 300
input <identifier> repeat_rate 30

Statusbar

sway ships with a default status bar in the form of swaybar which runs in a pure Wayland environment. swaybar can call a shell script or other program to show information in the status bar. See sway-bar(5) and swaybar-protocol(7) for details.

Installing the program i3status is an option to obtain a practical, default status bar under Wayland. All one has to do is add following snippet at the end of your sway config:

~/.config/sway/config
bar {
    status_command i3status
}

If you want to achieve colored output of i3status, you can adjust following part in the i3status configuration:

~/.config/i3status/config
general {
    colors = true
    interval = 5
}

In both examples, the system-wide installed configuration files have been copied over to the user directory and then modified.

Tip: waybar is an alternative to the bar included with sway (swaybar).

Wallpaper

Since release 1.1.1 the wallpaper part of the SwayWM project was moved to swaybg, which is needed in order to run the output command.

This line, which can be appended at the end of your sway configuration, sets a background image on all displays (output matches all with name "*"):

~/.config/sway/config
output "*" bg /path/to/image fill

Of course you have to replace the file name and path according to your wallpaper.

You may use azoteAUR as the GTK3 frontend to swaybg.

Solid colors may be set as follows:

output * bg #000000 solid_color

Input devices

It is possible to tweak specific input device configurations. For example, to enable tap-to-click and natural scrolling for all touchpads:

~/.config/sway/config
input type:touchpad {
    tap enabled
    natural_scroll enabled
}

To set configuration for a particular touchpad, use swaymsg -t get_inputs to obtain a device identifier and use it instead of type:touchpad. For example, to set pointer acceleration:

~/.config/sway/config
input "2:14:ETPS/2_Elantech_Touchpad" pointer_accel 0.2
Note: The output from the swaymsg -t get_inputs command may contain "\" to escape symbols like "/" (e.g. "2:14:ETPS\/2_Elantech_Touchpad") and it needs to be removed.

More documentation and options like acceleration profiles can be found in sway-input(5).

HiDPI

Set your displays scale factor with the output command in your config file. The scale factor can be fractional, but it is usually 2 for HiDPI screens.

output <name> scale <factor>

You can find your display name with the following command:

$ swaymsg -t get_outputs

Custom keybindings

Special keys on your keyboard can be used to execute commands, for example to control volume, monitor brightness or media players:

~/.config/sway/config
bindsym XF86AudioRaiseVolume exec pactl set-sink-volume @DEFAULT_SINK@ +5%
bindsym XF86AudioLowerVolume exec pactl set-sink-volume @DEFAULT_SINK@ -5%
bindsym XF86AudioMute exec pactl set-sink-mute @DEFAULT_SINK@ toggle
bindsym XF86AudioMicMute exec pactl set-source-mute @DEFAULT_SOURCE@ toggle
bindsym XF86MonBrightnessDown exec brightnessctl set 5%-
bindsym XF86MonBrightnessUp exec brightnessctl set +5%
bindsym XF86AudioPlay exec playerctl play-pause
bindsym XF86AudioNext exec playerctl next
bindsym XF86AudioPrev exec playerctl previous

See PulseAudio#Keyboard volume control, Advanced Linux Sound Architecture#Keyboard volume control, Backlight#Backlight utilities and MPRIS for details and alternative utilities.

To allow a keybinding to be executed while the lockscreen is active add the --locked parameter to bindsym.

bindsym --locked XF86AudioPlay exec playerctl play-pause

Graphical indicator bars

It is often desirable to have the current level of some percentage-valued setting, such as brightness or volume, be indicated by a graphical bar when it is adjusted. A good option for providing this facility in Sway is wobAUR (alternatively wob-gitAUR), which provides a subset of the functionality of the popular X tool xobAUR but as a native Wayland utility implementing the layer-shell protocol. See the project website for usage examples.

Floating windows

To enable floating windows or window assignments, open the application and then use the app_id, the class, the instance and the title attributes to enable floating windows/window assignments. The following command will list the properties of all the open windows.

$ swaymsg -t get_tree

To get only the app_id's of all open windows use:

$ swaymsg -t get_tree | grep "app_id"

To get the app_id of the focused window use:

$ swaymsg -t get_tree | jq -r '..|try select(.focused == true)'

If the app_id happens to be null for some windows, you might have to use the class and/or the instance attributes to enable floating mode/window assignments. You can search the output and create fine grained rules for your windows.

~/.config/sway/config
for_window [app_id="galculator"] floating enable
assign [class="firefox"] -> 3
assign [class="^Urxvt$" instance="^htop$"] -> 9

This is similar to using xorg-xprop to find the class or wm_name attributes in X11.

Xresources

Copy ~/.Xresources to ~/.Xdefaults to use them in Sway.

Xwayland

If a program crashes on start with the error message "cannot open display," it is likely that the program you are using is an X11 program. In order to use the Xwayland compatibility layer to run X11 programs under Wayland, it is necessary to install the xorg-server-xwayland package.

If you would like to disable Xwayland entirely and run a "pure" Wayland session, uninstall the xorg-server-xwayland package and set the following configuration option:

~/.config/sway/config
xwayland disable
Note: Some programs need special environment variables or configuration options to run natively under Wayland, and other programs (including most proprietary applications) do not support Wayland at all. Currently it is recommended to keep Xwayland on so that legacy applications can be used.

Tips and tricks

Autostart on login

To start sway from tty1 on login with default US keyboard, edit:

~/.bash_profile
if [[ -z $DISPLAY ]] && [[ $(tty) = /dev/tty1 ]]; then
  XKB_DEFAULT_LAYOUT=us exec sway
fi

Enable CapsLock/NumLock

Enable the capslock and/or numlock by adding the following lines to your sway config

~/.config/sway/config
input * xkb_capslock enable
input * xkb_numlock enable

Current keyboard layout

The current keyboard layout can be retrieved as follows, where kbd_identifier needs to be replaced with your keyboard's identifier:

$ swaymsg -t get_inputs | jq -r '.[] | select(.identifier == "kbd_identifier") | .xkb_active_layout_name'

Backlight toggle

To turn off (and on) your displays with a key (e.g. Pause) bind the following script in your Sway config:

#!/bin/sh
read lcd < /tmp/lcd
    if [ "$lcd" -eq "0" ]; then
        swaymsg "output * dpms on"
        echo 1 > /tmp/lcd
    else
        swaymsg "output * dpms off"
        echo 0 > /tmp/lcd
    fi

Screen capture and screen sharing

See Screen capture#Wayland.

Control swaynag with the keyboard

Swaynag, the default warning/prompt program shipped with sway, only supports user interaction with the mouse. A helper program such as swaynagmodeAUR may be used to enable interaction via keyboard shortcuts.

Swaynagmode works by first launching swaynag, then listening for signals which trigger actions such as selecting the next button, dismissing the prompt, or accepting the selected button. These signals are sent by launching another instance of the swaynagmode script itself with a control argument, such as swaynagmode --select right or swaynagmode --confirm.

Swaynagmode by default triggers the sway mode nag upon initialization, followed by default on exit. This makes it easy to define keybindings in your sway configuration:

~/.config/sway/config
set $nag exec swaynagmode
mode "nag" {
  bindsym {
    Ctrl+d    mode "default"

    Ctrl+c    $nag --exit
    q         $nag --exit
    Escape    $nag --exit

    Return    $nag --confirm

    Tab       $nag --select prev
    Shift+Tab $nag --select next

    Left      $nag --select next
    Right     $nag --select prev

    Up        $nag --select next
    Down      $nag --select prev
  }
}

Note that, beginning in sway version 1.2, mode names are case-sensitive.

You can configure sway to use swaynagmode with the configuration command swaynag_command swaynagmode.

Change cursor theme and size

To set the cursor theme and size:

~/.config/sway/config
seat seat0 xcursor_theme my_cursor_theme my_cursor_size

Where my_cursor_theme can be set to or replaced by a specific value like default, Adwaita or Simple-and-Soft, and my_cursor_size a value like 48.

You can inspect their values with echo $XCURSOR_SIZE and echo $XCURSOR_THEME.

Note that you need to restart the application to see the changes.

Note: Wayland uses client-side cursors. It's possible that applications do not evaluate the values of $XCURSOR_SIZE and $XCURSOR_THEME.

Troubleshooting

Application launchers

i3-dmenu-desktop, dmenu, and rofi all function relatively well in Sway, but all run under XWayland and suffer from the same issue where they can become unresponsive if the cursor is moved to a native Wayland window. The reason for this issue is that Wayland clients/windows do not have access to input devices unless they have focus of the screen. The XWayland server is itself a client to the Wayland compositor, so one of its XWayland clients must have focus for it to access user input. However, once one of its clients has focus, it can gather input and make it available to all XWayland clients through the X11 protocol. Hence, moving the cursor to an XWayland window and pressing Escape should fix the issue, and sometimes running pkill does too.

bemenu is a native Wayland dmenu replacement which can optionally be combined with j4-dmenu-desktopAUR to provide a Wayland-native combination for launching desktop files (as i3-dmenu-desktop does):

j4-dmenu-desktop --dmenu='bemenu -i --nb "#3f3f3f" --nf "#dcdccc" --fn "pango:DejaVu Sans Mono 12"' --term='termite'

You may need to set BEMENU_BACKEND environment variable to "wayland" if you choose not to disable XWayland.

You can also build your own with a floating terminal and fzf as discussed in a GitHub issue.

Also krunner binary provided by plasma-workspace package can serve as launcher, offering both XWayland and native Wayland support.

rofi-lbonn-wayland-gitAUR is a fork of rofi that works in Wayland and also has an -x11 flag if you need to launch it in an X11 session.

wofi-hgAUR is a command launcher, that provides some of the same features as rofi but running under Wayland. wofi lacks some features from rofi like an SSH mode and a window-switching mode. It is based on wlroots library and use GTK3 for rendering. It works pretty well with sway.

Virtualization

Sway works with both VirtualBox and VMware ESXi.

Unable to start Sway from tty

For ESXi, you need to enable 3D support under the Hardware Configuration > Video card settings. See also VMware#Enable 3D graphics on Intel and Optimus.

No visible cursor

When using the VMSVGA graphics controller, the cursor is invisible. This can be fixed by using software cursors as discussed in [2]:

$ export WLR_NO_HARDWARE_CURSORS=1

Sway socket not detected

Using a swaymsg argument, such as swaymsg -t get_outputs, will sometimes return the message:

sway socket not detected.
ERROR: Unable to connect to

when run inside a terminal multiplexer (such as gnu screen or tmux). This means swaymsg could not connect to the socket provided in your SWAYSOCK.

To view what the current value of SWAYSOCK is, type:

$ env | fgrep SWAYSOCK
SWAYSOCK=/run/user/1000/sway-ipc.1000.4981.sock

To work around this problem, you may try attaching to a socket based on the running sway process:

$ export SWAYSOCK=/run/user/$(id -u)/sway-ipc.$(id -u).$(pgrep -x sway).sock

To avoid this error, run the command outside of a multiplexer.

Unable to retrieve socket path

Requesting messages from swaymsg -t on a tty may return the following message:

Unable to retrieve socket path

SWAYSOCK environment variable is set after launching Sway, therefore a workaround to this error is to request swaymsg -t [message] in a terminal inside Sway.

Keybindings and keyboard layouts

By default, if you are using more than one keyboard layout, e.g. input * xkb_layout "us,ru", bindings may become broken when you switch on some secondary layout.

Thanks to https://github.com/swaywm/sway/pull/3058, all you need is to add --to-code key to sensitive bindsym lines like this:

bindsym --to-code {
  $mod+$left focus left
  $mod+$down focus down
  $mod+$up focus up
  $mod+$right focus right
}

Java applications

Some Java-based applications will display blank screen when opened, for example any Intellij editor. To mitigate this, the application can be started with the _JAVA_AWT_WM_NONREPARENTING environment variable set to 1.

If you start the application from a launcher like rofi or dmenu, you might want to modify the application desktop entry as shown in Desktop entries#Modify environment variables.

Some issues with Java applications have been fixed in OpenJDK 11 and Sway 1.5. However, certain applications require additional configuration to use newer versions of OpenJDK, in the case of JetBrains IDEs you must set STUDIO_JDK=/usr/lib/jvm/java-11-openjdk-amd64/. [3]

Scroll on border

If using the mouse scroll wheel on an application's border crashes sway, you could use border none for the app_id (e.g. Firefox).

See also