Add icon support to eframe

[phoglund]

Example code using this (uses the image crate to load images):

pub fn load_icon(icon_bytes: &Vec<u8>) -> Option<epi::IconData> {
    if let Ok(image) = image::load_from_memory(icon_bytes) {
        let image = image.to_rgba8();
        let (width, height) = image.dimensions();
        Some(epi::IconData {
            width,
            height,
            rgba: image.as_raw().to_vec(),
        })
    } else {
        None
    }
}

impl epi::App for EmbarkSubmitApp {
     ...
    fn icon_data(&self) -> Option<epi::IconData> {
        let icon_bytes = include_bytes!("../icons/my_icon.png");
        crate::icon::load_icon(&icon_bytes.to_vec())
    }

[emilk]

Very cool, thank you!

Please add a line in eframe/CHANGELOG.md too

[emilk]

Thank you!

[felipetesc]

Example built changing https://github.com/emilk/egui/blob/master/egui_demo_lib/src/apps/http_app.rs;

Just another sample (tested on Windows 10):

use eframe::{egui};
use eframe::epi::IconData;
use image;

#[allow(dead_code)]
pub struct Image {
    size: (usize, usize),
    pixels: Vec<egui::Color32>,
}

#[allow(dead_code)]
impl Image {
    pub fn open_icon_data(path : &str) -> std::option::Option<IconData>{
        
        let image_buffer = image::open(path).unwrap();
        let img = image_buffer.to_rgba8();
        let size = (img.width() as u32, img.height() as u32);
        let pixels = img.into_vec();
        let icon_data = eframe::epi::IconData{
            rgba: pixels,
            width: size.0 ,
            height: size.1,
        };
        Some(icon_data) 
    }
    pub fn open_image(path : &str) -> Option<Image>{
        
        let image_buffer = image::open(path).unwrap();
        let img = image_buffer.to_rgb8();
        let size = (img.width() as usize, img.height() as usize);
        let pixels = img.into_vec();
        let pixels = pixels
            .chunks(4)
            .map(|p| egui::Color32::from_rgba_unmultiplied(p[0], p[1], p[2], p[3]))
            .collect();
        Some(Image { size, pixels })
    }

    pub fn decode(bytes: &[u8]) -> Option<Image> {
        use image::GenericImageView;
        let image = image::load_from_memory(bytes).ok()?;
        let image_buffer = image.to_rgba8();
        let size = (image.width() as usize, image.height() as usize);
        let pixels = image_buffer.into_vec();
        assert_eq!(size.0 * size.1 * 4, pixels.len());
        let pixels = pixels
            .chunks(4)
            .map(|p| egui::Color32::from_rgba_unmultiplied(p[0], p[1], p[2], p[3]))
            .collect();

        Some(Image { size, pixels })
    }
}

Usage:

#![forbid(unsafe_code)]
#![cfg_attr(not(debug_assertions), deny(warnings))] // Forbid warnings in release builds
#![warn(clippy::all, rust_2018_idioms)]

mod view;
mod resources;

//mod created at src/resources/img.rs 
use resources::img::Image;
//app.rs moved from https://github.com/emilk/egui_template/src/app.rs  to https://github.com/emilk/egui_template/src/view/app.rs
use crate::view::app::App;

//#[cfg(not(target_arch = "wasm32"))]
fn main() {
    
    let icon_data = Image::open_icon_data("favicon32x32.png");
    
    let app = App::default();

    let mut native_options = eframe::NativeOptions::default();
    
    native_options.icon_data =  icon_data;
    
    eframe::run_native(Box::new(app), native_options);
}
}

The file favicon32x32.png was placed at the same level to cargo.toml

Window Screenshot:

Taskbar Screenshot:

[emilk]

@felipetesc Thanks for the example code! I think it's probably better to include the icon with include_bytes!, e.g. let icon_data = Image::decode_icon_data(include_bytes!("favicon32x32.png"));. That way you won't have any problems with working directories or forgetting to ship the icon with your binary.

[mjehrhart]

Does this work on macOS too or only windows?

[felipetesc]

I can't test on MacOS, don't have a Mac. If I could I would. If I remember correct, I used Linux too.