Lazy objects¶

The lazy.lazy object is a special helper object to specify a command for later execution. This object acts like the root of the object graph, which means that we can specify a key binding command with the same syntax used to call the command through a script or through qtile shell.

Example¶

from libqtile.config import Key
from libqtile.command import lazy

keys = [
    Key(
        ["mod1"], "k",
        lazy.layout.down()
    ),
    Key(
        ["mod1"], "j",
        lazy.layout.up()
    )
]

Lazy functions¶

This is overview of the commonly used functions for the key bindings. These functions can be called from commands on the Qtile object or on another object in the command tree.

Some examples are given below.

General functions¶

function	description
`lazy.spawn("application")`	Run the `application`
`lazy.spawncmd()`	Open command prompt on the bar. See prompt widget.
`lazy.reload_config()`	Reload the config.
`lazy.restart()`	Restart Qtile. In X11, it won't close your windows.
`lazy.shutdown()`	Close the whole Qtile

Group functions¶

function	description
`lazy.next_layout()`	Use next layout on the actual group
`lazy.prev_layout()`	Use previous layout on the actual group
`lazy.screen.next_group()`	Move to the group on the right
`lazy.screen.prev_group()`	Move to the group on the left
`lazy.screen.toggle_group()`	Move to the last visited group
`lazy.group.next_window()`	Switch window focus to next window in group
`lazy.group.prev_window()`	Switch window focus to previous window in group
`lazy.group["group_name"].toscreen()`	Move to the group called `group_name`. Takes an optional `toggle` parameter (defaults to False). If this group is already on the screen, it does nothing by default; to toggle with the last used group instead, use `toggle=True`.
`lazy.layout.increase_ratio()`	Increase the space for master window at the expense of slave windows
`lazy.layout.decrease_ratio()`	Decrease the space for master window in the advantage of slave windows

Window functions¶

function	description
`lazy.window.kill()`	Close the focused window
`lazy.layout.next()`	Switch window focus to other pane(s) of stack
`lazy.window.togroup("group_name")`	Move focused window to the group called `group_name`
`lazy.window.toggle_floating()`	Put the focused window to/from floating mode
`lazy.window.toggle_fullscreen()`	Put the focused window to/from fullscreen mode

Screen functions¶

function	description
`lazy.screen.set_wallpaper(path, mode=None)`	Set the wallpaper to the specificied image. Possible modes: `None` no resizing, `'fill'` centre and resize to fill screen, `'stretch'` stretch to fill screen.

ScratchPad DropDown functions¶

function	description
`lazy.group["group_name"].dropdown_toggle("name")`	Toggles the visibility of the specified DropDown window. On first use, the configured process is spawned.
`lazy.group["group_name"].hide_all()`	Hides all DropDown windows.
`lazy.group["group_name"].dropdown_reconfigure("name", **configuration)`	Update the configuration of the named DropDown.

User-defined functions¶

function	description
`lazy.function(func, args, *kwargs)`	Calls `func(qtile, args, *kwargs)`. NB. the `qtile` object is automatically passed as the first argument.

Examples¶

lazy.function can also be used as a decorator for functions.

from libqtile.config import Key
from libqtile.command import lazy

@lazy.function
def my_function(qtile):
    ...

keys = [
    Key(
        ["mod1"], "k",
        my_function
    )
]

Additionally, you can pass arguments to user-defined function in one of two ways:

In-line definition

Arguments can be added to the lazy.function call.

from libqtile.config import Key
from libqtile.command import lazy
from libqtile.log_utils import logger

def multiply(qtile, value, multiplier=10):
    logger.warning(f"Multiplication results: {value * multiplier}")

keys = [
    Key(
        ["mod1"], "k",
        lazy.function(multiply, 10, multiplier=2)
    )
]

Decorator

Arguments can also be passed to the decorated function.

from libqtile.config import Key
from libqtile.command import lazy
from libqtile.log_utils import logger

@lazy.function
def multiply(qtile, value, multiplier=10):
    logger.warning(f"Multiplication results: {value * multiplier}")

keys = [
    Key(
        ["mod1"], "k",
        multiply(10, multiplier=2)
    )
]