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.

API

mod linegauge: sig {
    type LineSet = [`Thin, `Thick, `Double];

    /// Creates a line gauge widget showing progress from 0.0 to 1.0
    val line_gauge: fn(
        ?#filled_style: &Style,
        ?#unfilled_style: &Style,
        ?#line_set: &LineSet,
        ?#label: &Line,
        ?#style: &Style,
        &f64
    ) -> Widget;
}

Parameters

• filled_style - Style for the filled portion
• unfilled_style - Style for the unfilled portion
• line_set - Character set: Thin, Thick (default), or Double
• label - Line or span displayed within the gauge
• style - Base style for the widget

Examples

Basic Usage

use tui;
use tui::line_gauge;

let progress = 0.75;  // 75%

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

Color-coded Status

use tui;
use tui::line_gauge;
use tui::block;
use tui::text;

{
    let clock = time::timer(duration:0.5s, true);
    let power = 0.0;
    power <- min(1.0, (clock ~ power) + 0.01);

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

    let percentage = cast<i64>(power * 100.0)?;

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

Compact Multi-metric Display

use tui;
use tui::line_gauge;
use tui::text;
use tui::layout;

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