foundations/io.daio.wild.foundation/restoreChildFocus

restoreChildFocus

fun Modifier.restoreChildFocus(onRestoreFailed: () -> FocusRequester? = null): Modifier

Utility Modifier to restore focus of a child within a focus group. A common use case is to restore the last focus child when navigating from a nested LazyRow within a LazyColumn.

This Modifier also applies focusGroup and focusRestorer.

Since

0.3.0

Example:

LazyColumn {
    items(20) {
        LazyRow(
            modifier = Modifier
                .fillMaxSize()
                .restoreChildFocus()
        ) {
            items(100) {
                Button(onClick = onClick) {
                    BasicText("Clickable")
                }
            }
        }
    }
}

Example focusing the first item in a lazy row:

LazyColumn {
    items(20) {
        val rowFirstItemRequester = remember { FocusRequester() }

        LazyRow(
            modifier = Modifier
                .fillMaxSize()
                // Use restore failed to only request focus to the first item
                // if restoring previous focused item fails.
                .restoreChildFocus(onRestoreFailed = { rowFirstItemRequester })
        ) {
            items(100) { index ->
                // Only add the focus requester if it is the first item in the row.
                Button(
                    modifier = Modifier.thenIf(
                        index == 0,
                        ifTrueModifier = Modifier.focusRequester(rowFirstItemRequester),
                    ),
                    onClick = onClick,
                ) {
                    BasicText("Clickable")
                }
            }
        }
    }
}

Parameters

onRestoreFailed

A callback if focus restoration fails within the applied focusRestorer.