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rustgtk

How can I increment a variable using GTK4 Button?

I have the following code excerpt:

let mut counter: u32 = 0;

button.connect_clicked(move |_|
    {
        counter+=1;
        flip_coin(&label)
    }
);

I want to increment the counter variable when I click the GTK4 button. How can I achieve this, since in the code excerpt I provided , counter is a captured variable in a Fn closure.

Solution

  • For this, you need to use the Cell class and to clone your element for it to be used inside the closure of the button.

    Small example :

    let counter = Rc::new(Cell::new(0));

button.connect_clicked(clone!(@strong counter => move |_| {
       counter.set(counter.get() + 1);
       println!("{}", counter.get());
}));

    More details here: Memory management with GTK4 and Rust