imgui-rs/imgui-examples/examples/slider.rs

use imgui::*;

mod support;

fn main() {
    let mut state = State::default();
    let system = support::init(file!());
    system.main_loop(move |run, ui| {
        example_selector(run, ui, &mut state);
        match state.example {
            1 => example_1(ui, &mut state),
            2 => example_2(ui, &mut state),
            _ => (),
        }
    });
}

fn example_selector(run: &mut bool, ui: &mut Ui, state: &mut State) {
    let w = Window::new(im_str!("Slider examples"))
        .opened(run)
        .position([20.0, 20.0], Condition::Appearing)
        .size([700.0, 80.0], Condition::Appearing)
        .resizable(false);
    w.build(&ui, || {
        let mut clicked = false;
        clicked |= ui.radio_button(im_str!("Example 1: Basic sliders"), &mut state.example, 1);
        clicked |= ui.radio_button(im_str!("Example 2: Slider arrays"), &mut state.example, 2);
        if clicked {
            state.reset();
        }
    });
}

fn example_1(ui: &Ui, state: &mut State) {
    let w = Window::new(im_str!("Example 1: Basic sliders"))
        .size([700.0, 340.0], Condition::Appearing)
        .position([20.0, 120.0], Condition::Appearing);
    w.build(&ui, || {
        ui.text("All of the following data types are supported:");
        ui.text("Signed:   i8 i16 i32 i64");
        ui.text("Unsigned: u8 u16 u32 u64");
        ui.text("Floats:   f32 f64");

        Slider::new(im_str!("u8 value"))
            .build(&ui, &mut state.u8_value);

        Slider::new(im_str!("f32 value"))
            .build(&ui, &mut state.f32_value);

        ui.separator();
        ui.text("Slider range can be limited:");
        Slider::new(im_str!("i32 value with range"))
            .range(-999 ..= 999)
            .build(&ui, &mut state.i32_value);
        ui.text("Note that for 32-bit/64-bit types, sliders are always limited to half of the natural type range!");

        ui.separator();
        ui.text("Value formatting can be customized with a C-style printf string:");
        Slider::new(im_str!("f64 value with custom formatting"))
            .range(-999_999_999.0 ..= 999_999_999.0)
            .display_format(im_str!("%09.0f"))
            .build(&ui, &mut state.f64_formatted);

        ui.separator();
        ui.text("Vertical sliders require a size parameter but otherwise work in a similar way:");
        VerticalSlider::new(im_str!("vertical\nu8 value"), [50.0, 50.0])
            .build(&ui, &mut state.u8_value);
    });
}

fn example_2(ui: &Ui, state: &mut State) {
    let w = Window::new(im_str!("Example 2: Slider arrays"))
        .size([700.0, 260.0], Condition::Appearing)
        .position([20.0, 120.0], Condition::Appearing);
    w.build(&ui, || {
        ui.text("You can easily build a slider group from an array of values:");
        Slider::new(im_str!("[u8; 4]"))
            .build_array(&ui, &mut state.array);

        ui.text("You don't need to use arrays with known length; arbitrary slices can be used:");
        let slice: &mut [u8] = &mut state.array[1..=2];
        Slider::new(im_str!("subslice"))
            .build_array(&ui, slice);
    });
}

#[derive(Default)]
struct State {
    example: u32,
    i32_value: i32,
    u8_value: u8,
    f32_value: f32,
    f64_formatted: f64,
    array: [u8; 4],
}

impl State {
    fn reset(&mut self) {}
}