callback_return_composable.kt

@Composable
fun CaptureBitmap(
  content: @Composable ()->Unit
) : () -> Bitmap // <---- this will return a callback which returns a bitmap
{
  
  val composeView = ComposeView(...)
  
  //callback that convert view to bitmap
  fun captureBitmap() = composeView.drawToBitmap() 
  
  AndroidView(
    factory = {
      composeView.apply {
        setContent {
          content.invoke() // <--- Content get places in between this code
        }
      }
    }
  )
  
  return ::captureBitmap // <--- return functional reference of the callback
}