Progress Bars

Fast-Rich provides a powerful progress bar system for tracking long-running tasks with multi-bar support, spinners, ETA, and customizable columns.

Quick Example

use fast_rich::prelude::*;
use std::thread;
use std::time::Duration;

fn main() {
    let progress = Progress::new();
    let task = progress.add_task("Processing...", Some(100));

    for _ in 0..100 {
        thread::sleep(Duration::from_millis(50));
        progress.advance(task, 1);
    }
}

---

Multi-Task Progress

Track multiple tasks simultaneously:

use fast_rich::prelude::*;
use std::thread;
use std::time::Duration;

fn main() {
    let progress = Progress::new();

    let download = progress.add_task("Downloading", Some(100));
    let extract = progress.add_task("Extracting", Some(50));
    let install = progress.add_task("Installing", Some(200));

    // Simulate work
    for i in 0..100 {
        thread::sleep(Duration::from_millis(30));
        progress.advance(download, 1);

        if i % 2 == 0 {
            progress.advance(extract, 1);
        }
        if i % 1 == 0 {
            progress.advance(install, 2);
        }
    }
}

Output:

Downloading ━━━━━━━━━━━━━━━━━━━━ 100% 00:00
Extracting  ━━━━━━━━━━━━━━━━━━━━ 100% 00:00
Installing  ━━━━━━━━━━━━━━━━━━━━ 100% 00:00

---

Task Management

Adding Tasks

// Known total (shows percentage)
let task1 = progress.add_task("Download", Some(total_bytes));

// Unknown total (shows spinner)
let task2 = progress.add_task("Scanning", None);

Updating Progress

// Advance by amount
progress.advance(task_id, 10);

// Set absolute progress
progress.set_completed(task_id, 50);

// Mark as complete
progress.set_completed(task_id, total);

Updating Description

progress.update_description(task_id, "Almost done...");

---

Spinners

For tasks with unknown duration, use spinners:

use fast_rich::prelude::*;

fn main() {
    let spinner = Spinner::new()
        .message("Loading...")
        .style(SpinnerStyle::Dots);

    // Use with Status for single-task indication
    let status = Status::new("Processing data");
    // ... do work ...
}

Spinner Styles

Style	Pattern
SpinnerStyle::Dots	⠋ ⠙ ⠹ ⠸ ⠼ ⠴ ⠦ ⠧ ⠇ ⠏
SpinnerStyle::Line	- \ | /
SpinnerStyle::Braille	⣾ ⣽ ⣻ ⢿ ⡿ ⣟ ⣯ ⣷

---

Customizable Columns

Progress bars can display different information columns:

use fast_rich::progress::*;

let progress = Progress::new()
    .with_columns(vec![
        ProgressColumn::Description,
        ProgressColumn::Bar,
        ProgressColumn::Percentage,
        ProgressColumn::TimeRemaining,
    ]);

Available Columns

Column	Description
Description	Task description text
Bar	Visual progress bar
Percentage	Completion percentage
Completed	Completed/Total count
TimeRemaining	Estimated time remaining
TransferSpeed	Transfer speed (bytes/sec)
Spinner	Animated spinner

---

Snapshot Rendering

For non-interactive output or logging, render progress as a string:

let progress = Progress::new();
let task = progress.add_task("Working...", Some(100));
progress.advance(task, 50);

// Get rendered string
let output = progress.render_to_string();
println!("{}", output);

This is useful for: - Logging progress state - Testing - Non-interactive environments

---

Real Terminal Output

Progress bar in action

Code

use fast_rich::prelude::*;
use std::thread;
use std::time::Duration;

fn main() {
    let progress = Progress::new();
    let download = progress.add_task("Downloading", Some(100));
    let extract = progress.add_task("Extracting", Some(50));
    let install = progress.add_task("Installing", Some(200));

    for i in 0..100 {
        thread::sleep(Duration::from_millis(30));
        progress.advance(download, 1);
        if i % 2 == 0 { progress.advance(extract, 1); }
        progress.advance(install, 2);
    }
}

Run it

cargo run --example progress_bar

What you'll see

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Tips

Use with Live Display

For the smoothest animations, combine Progress with Live:

use fast_rich::live::Live;
// Progress automatically integrates with Live when rendered

Update Rate

Don't update progress too frequently. For very fast iterations, batch updates or use a timer to limit refresh rate.

Terminal Compatibility

Progress bars use ANSI cursor control. They work best in interactive terminals. In CI environments, consider using snapshot rendering or simpler output.