Configuring i3 window manager (I3WM) on debian (Jessie) lenovo thinkpad x260

Before going into the details of configuring i3wm, let me first introduce you to The Documentation of i3wm! Seriously. I don't even know why I'm writing this. Their documentation is fucking awesome! Firstly, I decided to go with i3wm, despite having Debian with Gnome is mainly because

1. Gnome-shell uses a lot of CPU.
2. I want longer battery life.
3. I don't like my CPU heating up.
4. If the CPU is being used by my OS, then it would slow everything else down.
5. It's so much cooler to use i3wm.

Firstly install i3wm and its siblings.

sudo apt-get update (Not really necessary.)
sudo apt-get install i3wm i3lock i3

After this, log out and then log in after selecting i3wm as your desktop environment. You will now be prompted to select the mod key. I would suggest that you select the Window key if that is available and not the Alt key. If you use the Alt key, then you won't be able to use the usual short-keys in other apps like chrome, firefox, VLC and quite literally the countless other apps that use Alt as a part of their default short-keys and I have no clue as to how to escape Alt in i3wm! Every short-key in i3wm begins with the mod key. Here are some of the default short-keys.

1. Mod + Enter↵ # New terminal
2. Mod + f # Fullscreen
3. Mod + h + Enter↵ # Horizontal split
4. Mod + v + Enter↵ # Vertical split
5. Mod + d # Application search
6. Mod + w # Tab layout of all open applications
7. Mod + s # Stack layout of all open applications
8. Mod + e # Return to default layout
9. Mod + 1/2/3/4/5/6/7/8/9 # Switch between the 9 workspaces
10. Mod + Shift + 1/2/3/4/5/6/7/8/9 # Shift an application to a specific workspace
11. Mod + Arrow Buttons # Select between windows
12. Mod + Shift + Arrow Buttons # Move windows
13. Mod + Shift + q # Quit application
14. Mod + Shift + e # Logout

The i3bar is where the battery life, internet status etc are displayed. It's quite basic and tiny. The ram usage is negligible. The i3status is a small program (about 1500 SLOC) for generating a status bar for i3bar. I will share my i3 config file as well as my i3status config file so that you can set yours accordingly. For setting a background image, I have used feh, an image viewer and cataloguer, for backlight I have used xbacklight and for touchpad settings I have used synclient. So before editing the config file runsudo apt-get install feh xbacklight synclient and then run vim ~/.i3/configin terminal. After editing the config file, reload the configuration by running i3-msg reload or hitting Mod+Shift+r.

# This file has been auto-generated by i4-config-wizard(1).
# It will not be overwritten, so edit it as you like.
#
# Should you change your keyboard layout some time, delete
# this file and re-run i3-config-wizard(1).
#

# i3 config file (v4)
#
# Please see http://i3wm.org/docs/userguide.html for a complete reference!

set $mod Mod4

# Font for window titles. Will also be used by the bar unless a different font
# is used in the bar {} block below.
# This font is widely installed, provides lots of unicode glyphs, right-to-left
# text rendering and scalability on retina/hidpi displays (thanks to pango).
font pango:DejaVu Sans Mono 8
# Before i3 v4.8, we used to recommend this one as the default:
# font -misc-fixed-medium-r-normal--13-120-75-75-C-70-iso10646-1
# The font above is very space-efficient, that is, it looks good, sharp and
# clear in small sizes. However, its unicode glyph coverage is limited, the old
# X core fonts rendering does not support right-to-left and this being a bitmap
# font, it doesn’t scale on retina/hidpi displays.

# Use Mouse+$mod to drag floating windows to their wanted position
floating_modifier $mod

# start a terminal
bindsym $mod+Return exec i3-sensible-terminal

# kill focused window
bindsym $mod+Shift+q kill

# start dmenu (a program launcher)
bindsym $mod+d exec dmenu_run
# There also is the (new) i3-dmenu-desktop which only displays applications
# shipping a .desktop file. It is a wrapper around dmenu, so you need that
# installed.
# bindsym $mod+d exec --no-startup-id i3-dmenu-desktop

# change focus
bindsym $mod+j focus left
bindsym $mod+k focus down
bindsym $mod+l focus up
bindsym $mod+semicolon focus right

# alternatively, you can use the cursor keys:
bindsym $mod+Left focus left
bindsym $mod+Down focus down
bindsym $mod+Up focus up
bindsym $mod+Right focus right

# move focused window
bindsym $mod+Shift+j move left
bindsym $mod+Shift+k move down
bindsym $mod+Shift+l move up
bindsym $mod+Shift+semicolon move right

# alternatively, you can use the cursor keys:
bindsym $mod+Shift+Left move left
bindsym $mod+Shift+Down move down
bindsym $mod+Shift+Up move up
bindsym $mod+Shift+Right move right

# split in horizontal orientation
bindsym $mod+h split h

# split in vertical orientation
bindsym $mod+v split v

# enter fullscreen mode for the focused container
bindsym $mod+f fullscreen

# change container layout (stacked, tabbed, toggle split)
bindsym $mod+s layout stacking
bindsym $mod+w layout tabbed
bindsym $mod+e layout toggle split

# toggle tiling / floating
bindsym $mod+Shift+space floating toggle

# change focus between tiling / floating windows
bindsym $mod+space focus mode_toggle

# focus the parent container
bindsym $mod+a focus parent

# focus the child container
#bindsym $mod+d focus child

# switch to workspace
bindsym $mod+1 workspace 1
bindsym $mod+2 workspace 2
bindsym $mod+3 workspace 3
bindsym $mod+4 workspace 4
bindsym $mod+5 workspace 5
bindsym $mod+6 workspace 6
bindsym $mod+7 workspace 7
bindsym $mod+8 workspace 8
bindsym $mod+9 workspace 9
bindsym $mod+0 workspace 10

# move focused container to workspace
bindsym $mod+Shift+1 move container to workspace 1
bindsym $mod+Shift+2 move container to workspace 2
bindsym $mod+Shift+3 move container to workspace 3
bindsym $mod+Shift+4 move container to workspace 4
bindsym $mod+Shift+5 move container to workspace 5
bindsym $mod+Shift+6 move container to workspace 6
bindsym $mod+Shift+7 move container to workspace 7
bindsym $mod+Shift+8 move container to workspace 8
bindsym $mod+Shift+9 move container to workspace 9
bindsym $mod+Shift+0 move container to workspace 10

# reload the configuration file
bindsym $mod+Shift+c reload
# restart i3 inplace (preserves your layout/session, can be used to upgrade i3)
bindsym $mod+Shift+r restart
# exit i3 (logs you out of your X session)
bindsym $mod+Shift+e exec "i3-nagbar -t warning -m 'You pressed the exit shortcut. Do you really want to exit i3? This will end your X session.' -b 'Yes, exit i3' 'i3-msg exit'"

# resize window (you can also use the mouse for that)
mode "resize" {
        # These bindings trigger as soon as you enter the resize mode

        # Pressing left will shrink the window’s width.
        # Pressing right will grow the window’s width.
        # Pressing up will shrink the window’s height.
        # Pressing down will grow the window’s height.
        bindsym j resize shrink width 10 px or 10 ppt
        bindsym k resize grow height 10 px or 10 ppt
        bindsym l resize shrink height 10 px or 10 ppt
        bindsym semicolon resize grow width 10 px or 10 ppt

        # same bindings, but for the arrow keys
        bindsym Left resize shrink width 10 px or 10 ppt
        bindsym Down resize grow height 10 px or 10 ppt
        bindsym Up resize shrink height 10 px or 10 ppt
        bindsym Right resize grow width 10 px or 10 ppt

        # back to normal: Enter or Escape
        bindsym Return mode "default"
        bindsym Escape mode "default"
}

bindsym $mod+r mode "resize"

# lockscreen
bindsym Control+$mod+l exec i3lock

# Start i3bar to display a workspace bar (plus the system information i3status
# finds out, if available)
bar {
        status_command i3status
}

# Touchpad settings
exec --no-startup-id synclient TapButton1=1 TapButton2=3 HorizTwoFingerScroll=1

# Pulse Audio control
# I haven't yet gotten this working yet. Soon enough!
bindsym XF86AudioRaiseVolume exec "amixer -q sset Master,0 1+ unmute"
bindsym XF86AudioLowerVolume exec "amixer -q sset Master,0 1- unmute"
bindsym XF86AudioMute exec "amixer -q sset Master,0 toggle"

# Screen brightness controls
# Ideally keep the increments/decrements to 5. I want a more fine tune
# and hence I keep it at 1.
bindsym XF86MonBrightnessUp exec xbacklight -inc 1
bindsym XF86MonBrightnessDown exec xbacklight -dec 1

# Background image
exec --no-startup-id feh --bg-fill ~/Pictures/IMG_4432.JPG

# Take Screenshot
# I couldn't get the Print Screen (PrtSrc) button to work so assigned 
# this instead.
bindsym $mod+z exec scrot

  The i3status config file decides what to display in the status bar. Memory usage, battery, CPU info, internet status etc. To edit this, run sudo vim /etc/i3status.conf . After editing file run i3status reload from command line.

# i3status configuration file.
# see "man i3status" for documentation.

# It is important that this file is edited as UTF-8.
# The following line should contain a sharp s:
# ß
# If the above line is not correctly displayed, fix your editor first!

general {
        colors = true
        interval = 5
}

order += "disk /"
order += "volume master"
order += "run_watch DHCP"
order += "run_watch VPN"
order += "wireless wlan0"
order += "ethernet eth0"
order += "battery 0"
order += "battery 1"
order += "cpu_usage"
order += "load"
order += "tztime local"

wireless wlan0 {
        format_up = "W: (%quality at %essid) %ip"
        format_down = "W: down"
}

volume master {
	format = "♪:%volume"
	device = "default"
	mixer = "Master"
	mixer_idx = 0
}

ethernet eth0 {
        # if you use %speed, i3status requires root privileges
        format_up = "E: %ip (%speed)"
        format_down = "E: down"
}

battery 0 {
        format = "%status %percentage %remaining"
}
battery 1 {
	format = "%status %percentage %remaining"
}

run_watch DHCP {
        pidfile = "/var/run/dhclient*.pid"
}

run_watch VPN {
        pidfile = "/var/run/vpnc/pid"
}

tztime local {
        format = "%Y-%m-%d %H:%M:%S"
}

load {
        format = "%1min"
}
cpu_usage {
	format = "%usage"
}
disk "/" {
        format = "%avail"
}

To lock screen after system suspends (close lid), we have to create a service in /etc/systemd/system and enable it. Run sudo vim /etc/systemd/system/i3lock.service and add the following.

# source: https://bbs.archlinux.org/viewtopic.php?pid=1170536#p1170536 by 65kid
#
[Unit]
Description=i3lock
Before=sleep.target

[Service]
User=vader
Type=forking
Environment=DISPLAY=:0
ExecStart=/usr/bin/i3lock

[Install]
WantedBy=sleep.target

Enable the service by running sudo systemctl enable i3lock.service. I3lock doesn't look that cool, but it gets the work done.  You can use any other screen lock instead of i3lock. No loyalty issues at all! Once that's done, your i3 window manager is complete and you are ready to use a cool and minimal tiling window manager. Command-line is cool! Rock on!