This blog post will discussed how the different widgets in the rofi window (re)size.

Resizing of the window

New in this version of rofi is that the whole interface sizes automatically. So if one widget gets bigger (because padding is changed) the parent widget size will adjust to make space.

Some widgets are allows to expand/shrink to fill the remaining size, others will always occupy the size they require. The entry box is one of those widgets.

This behaviour is modelled after GTK.

The figure below shows how the different widgets are packed together. The widgets marked with + will grow/shrink to fit the remaining space.

Note when fullscreen is enabled, this behaviour is changed.

How the size of the listview is determined

The listview widget is the most interesting widget if it comes to sizing, as it shows dynamic content. It is one of the widgets that determines the height of the window. However, in contrary to the rest of the widgets, every element in the listview is sized by the listview, and not the content in the element. While it is possible to set different margins, font-sizes for different elements in the listview this is discouraged. The reason for this is speed, by keeping the size of each element fixed, a lot of sizing calculations can be avoided. In the future this behaviour might change.

There are two options that affect how the listview in rofi resizes based on filtering.

• fixed-height: Force rofi to always show all configured rows (line setting), even when empty.
• dynamic: Resize when the list gets filtered.

The fixed-height setting override the dynamic setting. This results in three possible situations:

Note when fullscreen is enabled, this behaviour is changed. The listview will then always fill up the remaining space.

Fixed-Height enabled

If fixed-height: true is set, the listview will always show the number of configured lines. This is the most static view. The listview widget will not resize.

Try yourself:

seq 0 20 | rofi -dmenu -theme-str '#window mainbox listview { fixed-height: true; lines: 10;}' -show run

Fixed-Height disabled, dynamic disabled

This corresponds to the initial behaviour of rofi. The number of rows in the list view is determined by the number of items to show, with a maximum of the lines setting. If you filter the list, it will not shrink.

So if you configure lines to be 10, then show 5 items, the listview will be 5 rows high. Filtering will not affect the size.

Try yourself:

seq 0 20 | rofi -dmenu -theme-str '#window mainbox listview { fixed-height: false; dynamic: false; lines: 10;}' 

Fixed-Height disabled, dynamic enabled

If you enable both, the listview will always resize to show the available number of rows with a maximum of the lines setting.

This means that filtering the list, will automatically resize the view.

Try yourself:

seq 0 20 | rofi -dmenu -theme-str '#window mainbox listview { fixed-height: false; dynamic: true; lines: 10;}' 

Font sizing and dpi.

One of the settings that is often is the biggest determining factor in sizing is the font. The font size is scaled based on DPI. This is all handled by pango.

How a font-size translates to on-screen pixels depends on the dpi setting. We currently support 3 options:

User specified

If you pass a number bigger then 2 to the dpi setting, it interprets this as the dpi value and passes this to pango.

Detect based on X11 screen size

This is the behaviour toolkits like gtk and windows managers like i3 determine the dpi size. The dpi is based on what X11 reports as the pixel and real-size of the default screen. This will give one dpi value for all monitors.

Detect base on monitor size

This is a more experimental option, that is also implemented in the latest Qt. It, if available, requests via xrandr the actual size of the monitor and number of pixels. Based on this the dpi is calculated for the monitor rofi is visible on.

This, in theory, would make fonts in rofi appear the same size on each connected monitor, even if they have different sizes and resolutions.

To see what DPI rofi detected, run rofi -h it contains a section showing what has been detected:

             ID: 0 (primary)                       ID: 1                             ID: 2
            name: eDP1                           name: DVI-I-2                     name: DVI-I-3
        position: 0,0                        position: 0,0                     position: 1920,0
            size: 2160,1440                      size: 1920,1080                   size: 1600,1200
            size: 250mm,170mm  dpi: 219,215      size: 480mm,268mm  dpi: 102,102   size: 367mm,275mm  dpi: 111,111

Note that not every monitor reports it size correctly.