How to create the Advanced Bottom menu bar and add animation in Rust

Hey my coders, I hope you do well. In this post, I will give you a beginner guide to create an advanced bottom menu bar with animation in Rust, you’d likely be using GUI frameworks like GTK, Druid, or egui. Rust itself doesn’t have a native GUI library, so these frameworks provide the needed functionality. Additionally, animation can be handled through either the GUI framework’s built-in tools or custom implementations.

Here’s a high-level guide for implementing a bottom menu bar with animation using egui (a popular immediate mode GUI framework for Rust):

Why Use egui for GUI Development in Rust?

egui is a Rust-native GUI framework that focuses on simplicity and performance. It is an immediate mode GUI, meaning the entire UI is redrawn each frame. This might sound inefficient, but egui is optimized for modern hardware and manages the redrawing efficiently.

The framework is especially suited for small-to-medium desktop applications, tools, and game interfaces. It is beginner-friendly and fits well into Rust’s ecosystem, making it a great choice for adding animations to UI elements.

Steps to Create Bottom Menu Bar and Add Animation in egui

1. Set up a Rust project with egui

If you don’t have an egui project yet, you need to create one:

cargo new animated_bottom_menu
cd animated_bottom_menu

Next, add the necessary dependencies to Cargo.toml:

[dependencies]
eframe = "0.23"

This will include the egui framework, which makes creating graphical applications easier.

2. Create the Bottom Menu Bar

In egui, you can create a bottom menu bar using a TopBottomPanel, specifying it to be placed at the bottom.

Here’s an example:

use eframe::egui;

fn main() {
    let options = eframe::NativeOptions::default();
    eframe::run_native(
        "Bottom Menu Bar",
        options,
        Box::new(|_cc| Box::new(MyApp::default())),
    );
}

struct MyApp {
    animation_progress: f32,
}

impl Default for MyApp {
    fn default() -> Self {
        Self {
            animation_progress: 0.0,
        }
    }
}

impl eframe::App for MyApp {
    fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
        // This will run every frame
        self.animation_progress += 0.01;
        if self.animation_progress > 1.0 {
            self.animation_progress = 0.0;
        }

        // Add a bottom panel for the menu bar
        egui::TopBottomPanel::bottom("bottom_menu").show(ctx, |ui| {
            ui.horizontal(|ui| {
                // Animate buttons using the progress value
                let scale = self.animation_progress.sin().abs();
                ui.add_space(scale * 20.0);

                if ui.button("Home").clicked() {
                    println!("Home clicked");
                }
                if ui.button("Settings").clicked() {
                    println!("Settings clicked");
                }
                if ui.button("Profile").clicked() {
                    println!("Profile clicked");
                }
            });
        });

        // Ensure that the screen continuously updates (for smooth animation)
        ctx.request_repaint();
    }
}

Explanation:

1. Bottom Panel: We use egui::TopBottomPanel::bottom to create a menu bar at the bottom of the window.
2. Animation: A simple animation is created by using a sine wave to change the spacing between menu items.
3. Repaint Request: ctx.request_repaint() ensures that the screen is continuously redrawn to animate the UI.

3. Add Animations

Animations in egui are often achieved using values that change over time (like a sine wave or a timer). For more complex animations (like fading, moving objects, or scaling buttons), you can use lerp (linear interpolation) or manipulate positions, sizes, or colors over time.

Extending the Example

You could make the animation more advanced by:

• Animating the color of the buttons.
• Adding hover effects.
• Animating the entire bottom bar sliding in and out.

Example for Sliding in Bottom Menu:

egui::TopBottomPanel::bottom("animated_bottom_menu")
    .min_height(self.animation_progress * 50.0)  // Animate the height
    .show(ctx, |ui| {
        ui.horizontal(|ui| {
            if ui.button("Home").clicked() {
                println!("Home clicked");
            }
            if ui.button("Settings").clicked() {
                println!("Settings clicked");
            }
            if ui.button("Profile").clicked() {
                println!("Profile clicked");
            }
        });
    });

Here, the height of the bottom menu bar is animated to slide in or out based on the self.animation_progress value.

Conclusion

By using egui, creating a bottom menu bar with animations in Rust becomes a relatively straightforward task. Immediate mode GUIs like egui make it easy to integrate animations by leveraging continuous repaints and simple functions like sine waves to manipulate the UI dynamically.

You can further extend this concept by adding more complex animations, transitions, and interactivity to your application’s UI. Rust, combined with egui, proves to be a powerful and performant tool for building modern graphical applications. Happy coding!