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BeyondBoundsLayout

public interface BeyondBoundsLayout


Layout extra items in the specified direction.

A BeyondBoundsLayout instance can be obtained by consuming the BeyondBoundsLayout modifier local. It can be used to send a request to layout more items in a particular direction. This can be useful when composition or layout is determined lazily, as with a LazyColumn. The request is received by any parent up the hierarchy that provides this modifier local.

Summary

Nested types

The scope used in BeyondBoundsLayout.layout.

value public final class BeyondBoundsLayout.LayoutDirection

The direction (from the visible bounds) that a BeyondBoundsLayout is requesting more items to be laid.

Public methods

abstract T

Send a request to layout more items in the specified direction.

Public methods

layout

abstract T <T extends Object> layout(
    @NonNull BeyondBoundsLayout.LayoutDirection direction,
    @ExtensionFunctionType @NonNull Function1<@NonNull BeyondBoundsLayout.BeyondBoundsScope, T> block
)

Send a request to layout more items in the specified direction. The request is received by a parent up the hierarchy. The parent adds one item at a time and calls block after each item is added. The parent continues adding new items as long as block returns null. Once you have all the items you need, you can perform some operation and return a non-null value. Returning this value stops the laying out of beyond bounds items. (Note that you have to return a non-null value stop iterating).

Parameters
@NonNull BeyondBoundsLayout.LayoutDirection direction

The direction from the visible bounds in which more items are requested.

@ExtensionFunctionType @NonNull Function1<@NonNull BeyondBoundsLayout.BeyondBoundsScope, T> block

Continue to layout more items until this block returns a non null item.

Returns
T

The value returned by the last run of block. If we layout all the available items then the returned value is null. When this function returns all the beyond bounds items may be disposed. Therefore you have to perform any custom logic within the block and return the value you need.