How to get an image object and update this image in rust

[CarbonPool]

Appreciate any help, I didn't find relevant examples

[FloVanGH]

You can found descriptions and examples on the rust documentation: https://slint-ui.com/releases/1.0.0/docs/rust/slint/struct.image. If you need more input feel free to ask.

[ogoffart]

If you have a property of type image, this is goinf to be a slint::Image which you can replace.

But what exactly do you mean by "updating" an image?

[ogoffart]

I think this is a bug.
We have a cache and and we don't reload the image if it was made from the same path.

slint/internal/core/graphics/image.rs

Lines 578 to 581 in 25b380b

	pub fn load_from_path(path: &std::path::Path) -> Result<Self, LoadImageError> {
	self::cache::IMAGE_CACHE.with(|global_cache| {
	let path: SharedString = path.to_str().ok_or(LoadImageError(()))?.into();
	global_cache.borrow_mut().load_image_from_path(&path).ok_or(LoadImageError(()))

@tronical should we always reload the image? or should we perhaps check the modtime of the file?

[Martoni]

Anyway, the way I do it is little bit overkill.
Saving the generated image on disk and re-load it is certainly not the best method.
But I'm learning Slint (and rust !) and I haven't found the right method yet.

[tronical]

Indeed, that's the bug. Suppose we have this in a .slint file:

Image {
    source: @image-url("foo.png");
}
Image {
    source: @image-url("foo.png");
}

Ideally we should load foo.png only once from disk. A modification time check seems indeed reasonable. The only other option I can think of is that the above .slint code would generate rust/c++ code that uses a different function (that doesn't check the modification time) and we make Image::load_from_path /always/ load from disk. But I don't quite like that either, so an extra stat() seems like the best option to me.

Sounds ok to you @ogoffart ?

[ogoffart]

True, you shouldn't need to save it on the disc, you can use slint::image::from_rgb8 or one of the other similar function. And you can probably find a way to convert your image to a slint::SharedPixelBuffer. the slint::Image documentation has some examples.

[Martoni]

Thanks @ogoffart , I find the way to do it properly ;)
https://github.com/Martoni/QRNote/blob/main/qr-note/src/main.rs