Progress Bars¶

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

Python-Style track() Iterator¶

The simplest way to add progress bars—just wrap any iterator:

use fast_rich::progress::track;
use std::thread;
use std::time::Duration;

fn main() {
    // Just like Python's: for item in track(range(100), description="Processing")
    for item in track(0..100, "Processing") {
        // Do work with each item
        thread::sleep(Duration::from_millis(50));
    }
}

Track demo

Manual Progress Control¶

For more control, use Progress directly:

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::progress::{Progress, SpinnerColumn, SpinnerStyle, TextColumn, BarColumn};
use fast_rich::console::Console;

fn main() {
    let columns: Vec<Box<dyn fast_rich::progress::ProgressColumn>> = vec![
        Box::new(SpinnerColumn::new().with_style(SpinnerStyle::Moon)),
        Box::new(TextColumn::new("[progress.description]")),
        Box::new(BarColumn::new(30)),
    ];

    let mut progress = Progress::new()
        .with_console(Console::new())
        .with_columns(columns);

    progress.start();
    let task = progress.add_task("Processing...", Some(100));
    // ... update progress ...
    progress.stop();
}

Spinner Styles¶

Fast-Rich includes 80+ spinner styles. Here are some popular ones:

Style	Pattern	Description
`SpinnerStyle::Dots`	`⠋ ⠙ ⠹ ⠸ ⠼ ⠴ ⠦ ⠧ ⠇ ⠏`	Classic braille dots (default)
`SpinnerStyle::Line`	`- \\ \| /`	Simple ASCII line
`SpinnerStyle::Moon`	🌑 🌒 🌓 🌔 🌕 🌖 🌗 🌘	Moon phases
`SpinnerStyle::Earth`	🌍 🌎 🌏	Rotating globe
`SpinnerStyle::Clock`	🕐 🕑 🕒 ... 🕛	Clock faces
`SpinnerStyle::Hearts`	💛 💙 💜 💚 ❤️	Color hearts
`SpinnerStyle::Star`	✶ ✸ ✹ ✺ ✹ ✷	Twinkling star
`SpinnerStyle::Arrow`	← ↖ ↑ ↗ → ↘ ↓ ↙	Rotating arrow
`SpinnerStyle::BouncingBar`	`[= ]` `[ = ]` ...	Bouncing bar
`SpinnerStyle::GrowHorizontal`	▏ ▎ ▍ ▌ ▋ ▊ ▉ █	Growing block
`SpinnerStyle::Aesthetic`	▰▱▱▱ ▰▰▱▱ ...	Aesthetic blocks

List All Spinners

use fast_rich::progress::SpinnerStyle;
println!("Available: {} styles", SpinnerStyle::all_names().len());

Run the spinner demo:

cargo run --example spinner_column_demo

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

Progress bar animation

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.

Try the Examples¶

Explore the full capabilities of progress bars and spinners:

# Basic progress bar demo
cargo run --example progress_rich

# Python-style track() iterator
cargo run --example docs_track

# All 85 spinner styles
cargo run --example all_spinners_demo

# Custom spinner configuration
cargo run --example spinner_column_demo
cargo run --example custom_spinner_api

# List available spinner names
cargo run --example list_spinners

These examples demonstrate: - ✅ Multi-task progress tracking - ✅ Custom columns (spinner, percentage, ETA, speed) - ✅ 85 spinner styles (emoji, ASCII, unicode) - ✅ track() iterator for simple loops - ✅ start()/stop()/refresh() lifecycle