recyclerview/androidx.recyclerview.widget/ItemTouchHelper/Callback/chooseDropTarget

chooseDropTarget

open fun chooseDropTarget(@NonNull selected: RecyclerView.ViewHolder, @NonNull dropTargets: List<RecyclerView.ViewHolder>, curX: Int, curY: Int): RecyclerView.ViewHolder(source)

Called by ItemTouchHelper to select a drop target from the list of ViewHolders that are under the dragged View.

Default implementation filters the View with which dragged item have changed position in the drag direction. For instance, if the view is dragged UP, it compares the view.getTop() of the two views before and after drag started. If that value is different, the target view passes the filter.

Among these Views which pass the test, the one closest to the dragged view is chosen.

This method is called on the main thread every time user moves the View. If you want to override it, make sure it does not do any expensive operations.

Return

A ViewHolder to whose position the dragged ViewHolder should be moved to.

Parameters

selected

The ViewHolder being dragged by the user.

dropTargets

The list of ViewHolder that are under the dragged View and candidate as a drop.

curX

The updated left value of the dragged View after drag translations are applied. This value does not include margins added by RecyclerView.ItemDecorations.

curY

The updated top value of the dragged View after drag translations are applied. This value does not include margins added by RecyclerView.ItemDecorations.