Showing the song's current time

Currently, we only display the progression of the song. The user has no way to know the duration and for how many seconds the song has been playing. Let's fix that by adding labels that will show the current time and the duration.

We'll need two new import statements in the main module:

use gtk::{Label, LabelExt};

We'll also add two label in our App structure:

struct App {
    adjustment: Adjustment,
    cover: Image,
    current_time_label: Label,
    duration_label: Label,
    playlist: Rc<Playlist>,
    state: Arc<Mutex<State>>,
    toolbar: MusicToolbar,
    window: Window,
}

One label for the current time and the other for the duration. Since we want to show the different label on the right of the cursor, we'll create a horizontal box, this code should be added in App::new():

let hbox = gtk::Box::new(Horizontal, 10);
vbox.add(&hbox);

let adjustment = Adjustment::new(0.0, 0.0, 10.0, 0.0, 0.0, 0.0);
let scale = Scale::new(Horizontal, &amp...