Hi folks, I’m writing the UI test with Compose on LazyVerticalGrid, Is there any way to assert that ...

# compose

[Long Tran]

Hi folks, I’m writing the UI test with Compose on LazyVerticalGrid, Is there any way to assert that x columns are displayed when I set columns = GridCells.Fixed(x) in LazyVerticalGrid?

[Abhishek Sharma]

I think you can do this using onChildPositioned callback. Maybe something like

var childCount = 0
LazyVerticalGrid(columns = GridCells.Fixed(x)) {
    items((1..100).toList()) {
        Text("Item $it")
        onChildPositioned {
            childCount++
        }
    }
}

// Assert that the number of children positioned within the grid is equal to x
assertEquals(x, childCount)

Btw, you might need to use the runBlockingTest as onChildPositioned is async.

[Zach Klippenstein (he/him) [MOD]]

Should be able to use the CollectionInfo semantics property: https://developer.android.com/reference/kotlin/androidx/compose/ui/semantics/SemanticsProperties#CollectionInfo()