Hello, everyone! I try to capture the bitmap of a ...

# compose

[Kyant]

Hello, everyone! I try to capture the bitmap of a composable container, using DrawModifierNode. The problem is that the ContentDrawScope.draw() won't be called when scrolling or clicking children (displaying ripples), unless recomposition happens.
Is my way correct to get the bitmap? I want to get the bitmap when the view changes every time.

[Kyant]

override fun ContentDrawScope.draw() {
    println("draw")
    val graphicsContext = requireGraphicsContext()
    val layer = graphicsContext.createGraphicsLayer()
    layer.record {
        drawRect(Color.White)
        [e-mail]()
    }
    coroutineScope.launch(<http://Dispatchers.IO|Dispatchers.IO>) {
        val bitmap = layer.toImageBitmap().asAndroidBitmap()
        graphicsContext.releaseGraphicsLayer(layer)
    }
    drawContent()
}

[Sergey Y.]

You can use OnPreDrawListener from ViewTreeObserver, which you can obtain from the current View. Here’s an example of how I’m using it for a similar purpose.

However, capturing a bitmap on every frame isn’t ideal, as it’s a memory-intensive operation. If your goal is to record the screen, the MediaProjection API is a more suitable solution.

[Sergey Y.]

(if you’re asking about compose on Android)

[Kyant]

Thank you very much, it works as my expectations.