The Line Gauge Widget

The line_gauge widget displays a horizontal progress indicator using line-drawing characters. It’s more compact than gauge and ideal for dashboards where vertical space is limited.

Interface

use super::{Line, Style, Tui};
type LineGauge = {
  filled_style: &[Style, null],
  filled_symbol: &[string, null],
  label: &[Line, null],
  ratio: &f64,
  style: &[Style, null],
  unfilled_style: &[Style, null],
  unfilled_symbol: &[string, null],
};

val line_gauge: fn(
  ?#filled_style: &[Style, null],
  ?#filled_symbol: &[string, null],
  ?#label: &[Line, null],
  ?#style: &[Style, null],
  ?#unfilled_style: &[Style, null],
  ?#unfilled_symbol: &[string, null],
  ratio: &f64
) -> Tui;

Parameters

• filled_style - Style for the filled portion
• filled_symbol - Character used to draw the filled portion
• unfilled_style - Style for the unfilled portion
• unfilled_symbol - Character used to draw the unfilled portion
• label - A Line displayed within the gauge
• style - Base style for the widget
• ratio (positional) - The filled fraction, from 0.0 to 1.0; a value outside that range is clamped, with a logged warning

Examples

Basic Usage

use tui::{style, line_gauge::line_gauge};

// 75%
let progress = 0.75;

line_gauge(
    #filled_style: &style(#fg: `Green),
    &progress
)

Color-coded Status

use tui::{line, style, block::block, line_gauge::line_gauge};

let percentage = min(100, count(sys::time::timer(0.5, true)));
let power = cast<f64>(percentage)$ / 100.0;

let color = select power {
    x if x < 0.10 => `Red,
    x if x < 0.25 => `Yellow,
    x => `Green
};

block(
    #border: &`All,
    #title: &line("Power"),
    &line_gauge(
        #filled_style: &style(#fg: color),
        #label: &line("[percentage]%"),
        &power
    )
)

Compact Multi-metric Display

use tui::{line, style, layout::{child, layout}, line_gauge::line_gauge};

layout(
    #direction: &`Vertical,
    &[
        child(#constraint: `Percentage(5), line_gauge(
            #filled_style: &style(#fg: `Red),
            #label: &line("CPU 45%"),
            &0.45
        )),
        child(#constraint: `Percentage(5), line_gauge(
            #filled_style: &style(#fg: `Yellow),
            #label: &line("MEM 67%"),
            &0.67
        )),
        child(#constraint: `Percentage(5), line_gauge(
            #filled_style: &style(#fg: `Green),
            #label: &line("DSK 23%"),
            &0.23
        ))
    ]
)

Use Cases

• System resource monitors (CPU, RAM, disk, network)
• Download/upload progress indicators
• Compact status dashboards
• Progress tracking in limited space

Comparison with gauge

Use line_gauge when:

• You need compact, single-line displays
• Vertical space is limited
• You want a more technical/modern look

Use gauge when:

• You have more vertical space available
• You want larger, more prominent indicators

See Also

• gauge - For block-style progress indicators
• sparkline - For historical trend display
• barchart - For categorical value comparison