To-Do List App with Slint and Rust

This is a simple to-do list app using the Slint GUI framework and Rust. It demonstrates how to manage UI elements, define interactive events, and manage state using the Rc (reference-counted) type for shared ownership.

Prerequisites

Before getting started, make sure you have the following installed:

• Rust: You can install it from the official Rust website here.
• Slint: Install Slint using Rust's package manager by adding it to your Cargo.toml or by using cargo add slint.

[dependencies]
slint = "0.1"

Project Structure:

• src/main.rs: List backend logic (implemented in Rust).
• ui/start_window.slint: User interface (created with Slint).

Code Breakdown

Step 1: Create the UI and Initialize the Model

In the main.rs file, we initialize the AppWindow and set up the necessary data structures to hold the to-do list items.

fn main() -> Result<(), Box<dyn Error>> {
    let ui = AppWindow::new()?;

Here, we initialize the AppWindow, which represents the UI. AppWindow::new() returns a result that we unwrap using ?.

Step 2: Create the Todo Model

We use Rc to hold the to-do items. Rc is a reference-counted pointer that allows multiple parts of the code to share ownership of the to-do model.

let todo_model = Rc::new(VecModel::from(vec![]));
ui.set_todo_model(todo_model.clone().into());

We start with an empty to-do list (Vec::new()), which will later be updated with user input. We pass this model to the UI via ui.set_todo_model().

Step 3: Implement add_item Callback

The first interactive feature is adding a to-do item. We define the callback for adding items to the model that takes as parameters the text from the input field.

let todo_model_adding = todo_model.clone();

This callback will be executed when the Add Item button is clicked. It simply adds a new to-do item to the model.

Step 4: Implement clear_all Callback

Next, we have to define a callback to clear all to-do items from the list:

let todo_model_clearing = todo_model.clone();

Create a callback that is tied to the Clear All button. When clicked, it clears the entire list of to-do items.

Step 5: Run the UI

Finally, we run the application:

ui.run()?;
Ok(())

} This will start the event loop and display the UI, waiting for user interactions.

Running the application

Run the following command:

cargo run