ImageBitmap to canvas using Glide/Coil-CodePudding

I'm using a @Composable where I need to pass via parameter an ImageBitmap, the problem is that I get the images from the server given an url so I need to load these images, convert them into a Bitmap and then to a ImageBitmap but I'm quite stuck because I don't know how to convert this to an ImageBitmap, this is my @Composable

@ExperimentalComposeUiApi
@Composable
fun MyCanvas(
    myImage: ImageBitmap,
    modifier: Modifier = Modifier,
) {
    Canvas(modifier = modifier
        .size(220.dp)
        .clipToBounds()
        .clip(RoundedCornerShape(size = 16.dp)) {

        ...
        val canvasWidth = size.width.toInt()
        val canvasHeight = size.height.toInt()
        val imageSize = IntSize(width = canvasWidth, height = canvasHeight)

        drawImage(
            image = myImage, dstSize = imageSize
        )
        ...
    }
}

So, when I call this @Composable I need to load the image but not sure how to start with and I need to know what's better either using Glide or Coil.

CodePudding user response：

You don't need ImageBitmap to draw it into Canvas. You can draw painter inside DrawScope. You don't even actually need Canvas function either. androidx.compose.foundation.Canvas is nothing other than Spacer with Modifier.drawBehind

@Composable
fun Canvas(modifier: Modifier, onDraw: DrawScope.() -> Unit) =
    Spacer(modifier.drawBehind(onDraw))

And answer to your question is

@Composable
private fun MyComposable() {
    val sizeModifier = Modifier
        .fillMaxWidth()

    val url =
        "https://avatars3.githubusercontent.com/u/35650605?s=400&u=058086fd5c263f50f2fbe98ed24b5fbb7d437a4e&v=4"

    Column(
        modifier =Modifier.fillMaxSize()
    ) {

      val painter =  rememberAsyncImagePainter(
            model = url
        )

        Canvas(modifier = Modifier
            .clip(RoundedCornerShape(size = 16.dp))
                .size(220.dp)
            ) {
                with(painter) {
                    draw(size = size)
                }
            }

    }
}

And when you apply Modifier.clip() you don't have to apply Modifier.clipToBounds()

Both are the same thing with clip uses shape extra to clipToBounds

/**
 * Clip the content to the bounds of a layer defined at this modifier.
 */
@Stable
fun Modifier.clipToBounds() = graphicsLayer(clip = true)

/**
 * Clip the content to [shape].
 *
 * @param shape the content will be clipped to this [Shape].
 */
@Stable
fun Modifier.clip(shape: Shape) = graphicsLayer(shape = shape, clip = true)

CodePudding user response：

So, obviously, Dr. Thrace has provided you with an optimum solution which he extracted out of his centuries of experience treating the diseased code. You could go with that. However, from the description you provided in the question, it seemed as if majorly all you wanted was just a way to convert a Bitmap to an ImageBitmap object. There's a handy dandy asImageBitmap() extension function available to use with bitmaps now. So, you could just leverage that easy.

Far as Glide vs Coil is concerned, both have popular API methods that I think achieve similar goals/performance. Now, as far as I can remember, Coil was the first to migrate to Compose. I've only used coil since I required fetching an image from a url and wanted to simply display it, so cool provided a pretty damn straight forward API for that, rememberCoilPainter() which worked like gravity. Haven't really used the other one but just Google both looking for a comparison. It'll be available absolutely, or just dig through the documentation of both to see which methods are available and design your code structure in your mind while doing so, choose the one that implements easier. The site isn't generally used for taking opinions so I'll leave it there. Nice trick might be - the better the documentation the better the API.