recyclerview/androidx.recyclerview.widget/LinearLayoutManager

LinearLayoutManager

open class LinearLayoutManager : RecyclerView.LayoutManager, ItemTouchHelper.ViewDropHandler, RecyclerView.SmoothScroller.ScrollVectorProvider(source)

(SESL variant) A RecyclerView.LayoutManager implementation which provides similar functionality to android.widget.ListView.

Inheritors

GridLayoutManager

GridLayoutManager

Constructors

LinearLayoutManager

constructor(context: Context)

Creates a vertical LinearLayoutManager

constructor(context: Context, orientation: Int, reverseLayout: Boolean)

constructor(context: Context, attrs: AttributeSet, defStyleAttr: Int, defStyleRes: Int)

Constructor used when layout manager is set in XML by RecyclerView attribute "layoutManager".

Types

@RestrictTo(value = LIBRARY)

open class SavedState : Parcelable

SmoothScrollerJumpIfNeeded

open inner class SmoothScrollerJumpIfNeeded : LinearSmoothScroller

Properties

val HORIZONTAL: Int = 0

val INVALID_OFFSET: Int = -2147483648

val VERTICAL: Int = 1

Functions

assertNotInLayoutOrScroll

open fun assertNotInLayoutOrScroll(message: String)

Checks if RecyclerView is in the middle of a layout or scroll and throws an IllegalStateException if it is.

canScrollHorizontally

open fun canScrollHorizontally(): Boolean

canScrollVertically

open fun canScrollVertically(): Boolean

collectAdjacentPrefetchPositions

open fun collectAdjacentPrefetchPositions(dx: Int, dy: Int, state: RecyclerView.State, layoutPrefetchRegistry: RecyclerView.LayoutManager.LayoutPrefetchRegistry)

Gather all positions from the LayoutManager to be prefetched, given specified momentum.

collectInitialPrefetchPositions

open fun collectInitialPrefetchPositions(adapterItemCount: Int, layoutPrefetchRegistry: RecyclerView.LayoutManager.LayoutPrefetchRegistry)

Gather all positions from the LayoutManager to be prefetched in preperation for its RecyclerView to come on screen, due to the movement of another, containing RecyclerView.

computeHorizontalScrollExtent

open fun computeHorizontalScrollExtent(state: RecyclerView.State): Int

Override this method if you want to support scroll bars.

computeHorizontalScrollOffset

open fun computeHorizontalScrollOffset(state: RecyclerView.State): Int

Override this method if you want to support scroll bars.

computeHorizontalScrollRange

open fun computeHorizontalScrollRange(state: RecyclerView.State): Int

Override this method if you want to support scroll bars.

computeScrollVectorForPosition

open fun computeScrollVectorForPosition(targetPosition: Int): PointF

Should calculate the vector that points to the direction where the target position can be found.

computeVerticalScrollExtent

open fun computeVerticalScrollExtent(state: RecyclerView.State): Int

Override this method if you want to support scroll bars.

computeVerticalScrollOffset

open fun computeVerticalScrollOffset(state: RecyclerView.State): Int

Override this method if you want to support scroll bars.

computeVerticalScrollRange

open fun computeVerticalScrollRange(state: RecyclerView.State): Int

Override this method if you want to support scroll bars.

findFirstCompletelyVisibleItemPosition

open fun findFirstCompletelyVisibleItemPosition(): Int

Returns the adapter position of the first fully visible view.

findFirstVisibleItemPosition

open fun findFirstVisibleItemPosition(): Int

Returns the adapter position of the first visible view.

findLastCompletelyVisibleItemPosition

open fun findLastCompletelyVisibleItemPosition(): Int

Returns the adapter position of the last fully visible view.

findLastVisibleItemPosition

open fun findLastVisibleItemPosition(): Int

Returns the adapter position of the last visible view.

findViewByPosition

open fun findViewByPosition(position: Int): View

Finds the view which represents the given adapter position.

generateDefaultLayoutParams

open fun generateDefaultLayoutParams(): RecyclerView.LayoutParams

Create a default LayoutParams object for a child of the RecyclerView.

getInitialPrefetchItemCount

open fun getInitialPrefetchItemCount(): Int

Gets the number of items to prefetch in collectInitialPrefetchPositions, which defines how many inner items should be prefetched when this LayoutManager's RecyclerView is nested inside another RecyclerView.

open fun getOrientation(): Int

Returns the current orientation of the layout.

getRecycleChildrenOnDetach

open fun getRecycleChildrenOnDetach(): Boolean

Returns whether LayoutManager will recycle its children when it is detached from RecyclerView.

getReverseLayout

open fun getReverseLayout(): Boolean

Returns if views are laid out from the opposite direction of the layout.

getStackFromEnd

open fun getStackFromEnd(): Boolean

isAutoMeasureEnabled

open fun isAutoMeasureEnabled(): Boolean

Returns whether the measuring pass of layout should use the AutoMeasure mechanism of RecyclerView or if it should be done by the LayoutManager's implementation of onMeasure.

isLayoutReversed

open fun isLayoutReversed(): Boolean

Query if the layout is in reverse order.

isSmoothScrollbarEnabled

open fun isSmoothScrollbarEnabled(): Boolean

Returns the current state of the smooth scrollbar feature.

onDetachedFromWindow

open fun onDetachedFromWindow(view: RecyclerView, recycler: RecyclerView.Recycler)

Called when this LayoutManager is detached from its parent RecyclerView or when its parent RecyclerView is detached from its window.

onFocusSearchFailed

open fun onFocusSearchFailed(focused: View, direction: Int, recycler: RecyclerView.Recycler, state: RecyclerView.State): View

Called when searching for a focusable view in the given direction has failed for the current content of the RecyclerView.

onInitializeAccessibilityEvent

open fun onInitializeAccessibilityEvent(event: AccessibilityEvent)

onInitializeAccessibilityNodeInfo

open fun onInitializeAccessibilityNodeInfo(@NonNull recycler: RecyclerView.Recycler, @NonNull state: RecyclerView.State, @NonNull info: AccessibilityNodeInfoCompat)

Called by the AccessibilityDelegate when the information about the current layout should be populated.

onLayoutChildren

open fun onLayoutChildren(recycler: RecyclerView.Recycler, state: RecyclerView.State)

Lay out all relevant child views from the given adapter.

onLayoutCompleted

open fun onLayoutCompleted(state: RecyclerView.State)

Called after a full layout calculation is finished.

onRestoreInstanceState

open fun onRestoreInstanceState(state: Parcelable)

Called when the RecyclerView is ready to restore the state based on a previous RecyclerView.

onSaveInstanceState

open fun onSaveInstanceState(): Parcelable

Called when the LayoutManager should save its state.

open fun prepareForDrop(@NonNull view: View, @NonNull target: View, x: Int, y: Int)

Called by the after a View is dropped over another View.

scrollHorizontallyBy

open fun scrollHorizontallyBy(dx: Int, recycler: RecyclerView.Recycler, state: RecyclerView.State): Int

Scroll horizontally by dx pixels in screen coordinates and return the distance traveled.

scrollToPosition

open fun scrollToPosition(position: Int)

Scroll the RecyclerView to make the position visible.

scrollToPositionWithOffset

open fun scrollToPositionWithOffset(position: Int, offset: Int)

Scroll to the specified adapter position with the given offset from resolved layout start.

scrollVerticallyBy

open fun scrollVerticallyBy(dy: Int, recycler: RecyclerView.Recycler, state: RecyclerView.State): Int

Scroll vertically by dy pixels in screen coordinates and return the distance traveled.

setInitialPrefetchItemCount

open fun setInitialPrefetchItemCount(itemCount: Int)

Sets the number of items to prefetch in collectInitialPrefetchPositions, which defines how many inner items should be prefetched when this LayoutManager's RecyclerView is nested inside another RecyclerView.

open fun setOrientation(orientation: Int)

Sets the orientation of the layout.

setRecycleChildrenOnDetach

open fun setRecycleChildrenOnDetach(recycleChildrenOnDetach: Boolean)

Set whether LayoutManager will recycle its children when it is detached from RecyclerView.

setReverseLayout

open fun setReverseLayout(reverseLayout: Boolean)

Used to reverse item traversal and layout order.

setSmoothScrollbarEnabled

open fun setSmoothScrollbarEnabled(enabled: Boolean)

When smooth scrollbar is enabled, the position and size of the scrollbar thumb is computed based on the number of visible pixels in the visible items.

setStackFromEnd

open fun setStackFromEnd(stackFromEnd: Boolean)

Compatibility support for setStackFromBottom

smoothScrollToPosition

open fun smoothScrollToPosition(recyclerView: RecyclerView, state: RecyclerView.State, position: Int)

Smooth scroll to the specified adapter position.

smoothScrollToPositionJumpIfNeeded

@RestrictTo(value = [RestrictTo.Scope.LIBRARY_GROUP_PREFIX])

open fun smoothScrollToPositionJumpIfNeeded(recyclerView: RecyclerView, state: RecyclerView.State, position: Int)

supportsPredictiveItemAnimations

open fun supportsPredictiveItemAnimations(): Boolean

Returns whether this LayoutManager supports "predictive item animations".