belongs to Maven artifact androidx.recyclerview:recyclerview:1.0.0-alpha1

LinearSnapHelper

public class LinearSnapHelper
extends SnapHelper

java.lang.Object
   ↳ androidx.recyclerview.widget.RecyclerView.OnFlingListener
     ↳ androidx.recyclerview.widget.SnapHelper
       ↳ androidx.recyclerview.widget.LinearSnapHelper


Implementation of the SnapHelper supporting snapping in either vertical or horizontal orientation.

The implementation will snap the center of the target child view to the center of the attached RecyclerView. If you intend to change this behavior then override SnapHelper.calculateDistanceToFinalSnap(RecyclerView.LayoutManager, View).

Summary

Public constructors

LinearSnapHelper()

Public methods

int[] calculateDistanceToFinalSnap(RecyclerView.LayoutManager layoutManager, View targetView)

Override this method to snap to a particular point within the target view or the container view on any axis.

View findSnapView(RecyclerView.LayoutManager layoutManager)

Override this method to provide a particular target view for snapping.

int findTargetSnapPosition(RecyclerView.LayoutManager layoutManager, int velocityX, int velocityY)

Override to provide a particular adapter target position for snapping.

Inherited methods

Public constructors

LinearSnapHelper

LinearSnapHelper ()

Public methods

calculateDistanceToFinalSnap

int[] calculateDistanceToFinalSnap (RecyclerView.LayoutManager layoutManager, 
                View targetView)

Override this method to snap to a particular point within the target view or the container view on any axis.

This method is called when the SnapHelper has intercepted a fling and it needs to know the exact distance required to scroll by in order to snap to the target view.

Parameters
layoutManager RecyclerView.LayoutManager: the RecyclerView.LayoutManager associated with the attached RecyclerView

targetView View: the target view that is chosen as the view to snap

Returns
int[] the output coordinates the put the result into. out[0] is the distance on horizontal axis and out[1] is the distance on vertical axis.

findSnapView

View findSnapView (RecyclerView.LayoutManager layoutManager)

Override this method to provide a particular target view for snapping.

This method is called when the SnapHelper is ready to start snapping and requires a target view to snap to. It will be explicitly called when the scroll state becomes idle after a scroll. It will also be called when the SnapHelper is preparing to snap after a fling and requires a reference view from the current set of child views.

If this method returns null, SnapHelper will not snap to any view.

Parameters
layoutManager RecyclerView.LayoutManager: the RecyclerView.LayoutManager associated with the attached RecyclerView

Returns
View the target view to which to snap on fling or end of scroll

findTargetSnapPosition

int findTargetSnapPosition (RecyclerView.LayoutManager layoutManager, 
                int velocityX, 
                int velocityY)

Override to provide a particular adapter target position for snapping.

Parameters
layoutManager RecyclerView.LayoutManager: the RecyclerView.LayoutManager associated with the attached RecyclerView

velocityX int: fling velocity on the horizontal axis

velocityY int: fling velocity on the vertical axis

Returns
int the target adapter position to you want to snap or RecyclerView.NO_POSITION if no snapping should happen