WearableLinearLayoutManager

Kotlin |Java

open class WearableLinearLayoutManager : LinearLayoutManager

kotlin.Any
↳	androidx.recyclerview.widget.RecyclerView.LayoutManager
	↳	androidx.recyclerview.widget.LinearLayoutManager
		↳	androidx.wear.widget.WearableLinearLayoutManager

This wear-specific implementation of LinearLayoutManager provides basic offsetting logic for updating child layout. For round devices it offsets the children horizontally to make them appear to travel around a circle. For square devices it aligns them in a straight list. This functionality is provided by the CurvingLayoutCallback which is set when constructing the this class with its default constructor WearableLinearLayoutManager(Context).

Summary

Nested classes
abstract	LayoutCallback Callback for interacting with layout passes.

Inherited constants
From class LinearLayoutManager Int HORIZONTAL Int INVALID_OFFSET Int VERTICAL

Public constructors
<init>(context: Context!, layoutCallback: WearableLinearLayoutManager.LayoutCallback!) Creates a WearableLinearLayoutManager for a vertical list.
<init>(context: Context!) Creates a WearableLinearLayoutManager for a vertical list.

Public methods
open WearableLinearLayoutManager.LayoutCallback?	getLayoutCallback()
open Unit	onLayoutChildren(recycler: RecyclerView.Recycler!, state: RecyclerView.State!)
open Int	scrollVerticallyBy(dy: Int, recycler: RecyclerView.Recycler!, state: RecyclerView.State!)
open Unit	setLayoutCallback(@Nullable layoutCallback: WearableLinearLayoutManager.LayoutCallback?) Set a particular instance of the layout callback for this WearableLinearLayoutManager.

Inherited functions

From class LayoutManager Unit addDisappearingView(child: View!) To be called only during onLayoutChildren(Recycler, State) to add a view to the layout that is known to be going away, either because it has been removed or because it is actually not in the visible portion of the container but is being laid out in order to inform RecyclerView in how to animate the item out of view. Views added via this method are going to be invisible to LayoutManager after the dispatchLayout pass is complete. They cannot be retrieved via getChildAt(int) or won't be included in getChildCount() method. Unit addDisappearingView(child: View!, index: Int) To be called only during onLayoutChildren(Recycler, State) to add a view to the layout that is known to be going away, either because it has been removed or because it is actually not in the visible portion of the container but is being laid out in order to inform RecyclerView in how to animate the item out of view. Views added via this method are going to be invisible to LayoutManager after the dispatchLayout pass is complete. They cannot be retrieved via getChildAt(int) or won't be included in getChildCount() method. Unit addView(child: View!) Add a view to the currently attached RecyclerView if needed. LayoutManagers should use this method to add views obtained from a Recycler using Recycler#getViewForPosition(int). Unit addView(child: View!, index: Int) Add a view to the currently attached RecyclerView if needed. LayoutManagers should use this method to add views obtained from a Recycler using Recycler#getViewForPosition(int). Unit assertInLayoutOrScroll(message: String!) Checks if RecyclerView is in the middle of a layout or scroll and throws an IllegalStateException if it is not. Unit attachView(@NonNull child: View, index: Int, lp: RecyclerView.LayoutParams!) Reattach a previously detached view. This method should not be used to reattach views that were previously detachAndScrapView(android.view.View, RecyclerView.Recycler) scrapped}. Unit attachView(@NonNull child: View, index: Int) Reattach a previously detached view. This method should not be used to reattach views that were previously detachAndScrapView(android.view.View, RecyclerView.Recycler) scrapped}. Unit attachView(@NonNull child: View) Reattach a previously detached view. This method should not be used to reattach views that were previously detachAndScrapView(android.view.View, RecyclerView.Recycler) scrapped}. Unit calculateItemDecorationsForChild(@NonNull child: View, @NonNull outRect: Rect) Calculates the item decor insets applied to the given child and updates the provided Rect instance with the inset values. The Rect's left is set to the total width of left decorations. The Rect's top is set to the total height of top decorations. The Rect's right is set to the total width of right decorations. The Rect's bottom is set to total height of bottom decorations. Note that item decorations are automatically calculated when one of the LayoutManager's measure child methods is called. If you need to measure the child with custom specs via View#measure(int, int), you can use this method to get decorations. Boolean checkLayoutParams(lp: RecyclerView.LayoutParams!) Determines the validity of the supplied LayoutParams object. This should check to make sure that the object is of the correct type and all values are within acceptable ranges. The default implementation returns true for non-null params. Int chooseSize(spec: Int, desired: Int, min: Int) Chooses a size from the given specs and parameters that is closest to the desired size and also complies with the spec. Unit detachAndScrapAttachedViews(@NonNull recycler: RecyclerView.Recycler) Temporarily detach and scrap all currently attached child views. Views will be scrapped into the given Recycler. The Recycler may prefer to reuse scrap views before other views that were previously recycled. Unit detachAndScrapView(@NonNull child: View, @NonNull recycler: RecyclerView.Recycler) Detach a child view and add it to a Recycler's scrap heap. Scrapping a view allows it to be rebound and reused to show updated or different data. Unit detachAndScrapViewAt(index: Int, @NonNull recycler: RecyclerView.Recycler) Detach a child view and add it to a Recycler's scrap heap. Scrapping a view allows it to be rebound and reused to show updated or different data. Unit detachView(@NonNull child: View) Temporarily detach a child view. LayoutManagers may want to perform a lightweight detach operation to rearrange views currently attached to the RecyclerView. Generally LayoutManager implementations will want to use detachAndScrapView(android.view.View, RecyclerView.Recycler) so that the detached view may be rebound and reused. If a LayoutManager uses this method to detach a view, it must reattach or fully remove the detached view before the LayoutManager entry point method called by RecyclerView returns. Unit detachViewAt(index: Int) Temporarily detach a child view. LayoutManagers may want to perform a lightweight detach operation to rearrange views currently attached to the RecyclerView. Generally LayoutManager implementations will want to use detachAndScrapView(android.view.View, RecyclerView.Recycler) so that the detached view may be rebound and reused. If a LayoutManager uses this method to detach a view, it must reattach or fully remove the detached view before the LayoutManager entry point method called by RecyclerView returns. Unit endAnimation(view: View!) Ends all animations on the view created by the ItemAnimator. View? findContainingItemView(@NonNull view: View) Traverses the ancestors of the given view and returns the item view that contains it and also a direct child of the LayoutManager. Note that this method may return null if the view is a child of the RecyclerView but not a child of the LayoutManager (e.g. running a disappear animation). RecyclerView.LayoutParams! generateLayoutParams(lp: LayoutParams!) Create a LayoutParams object suitable for this LayoutManager, copying relevant values from the supplied LayoutParams object if possible. Important: if you use your own custom LayoutParams type you must also override checkLayoutParams(LayoutParams), generateLayoutParams(android.view.ViewGroup.LayoutParams) and generateLayoutParams(android.content.Context, android.util.AttributeSet). RecyclerView.LayoutParams! generateLayoutParams(c: Context!, attrs: AttributeSet!) Create a LayoutParams object suitable for this LayoutManager from an inflated layout resource. Important: if you use your own custom LayoutParams type you must also override checkLayoutParams(LayoutParams), generateLayoutParams(android.view.ViewGroup.LayoutParams) and generateLayoutParams(android.content.Context, android.util.AttributeSet). Int getBaseline() Returns offset of the RecyclerView's text baseline from the its top boundary. Int getBottomDecorationHeight(@NonNull child: View) Returns the total height of item decorations applied to child's bottom. Note that this value is not updated until the View is measured or calculateItemDecorationsForChild(View, Rect) is called. View? getChildAt(index: Int) Return the child view at the given index Int getChildCount() Return the current number of child views attached to the parent RecyclerView. This does not include child views that were temporarily detached and/or scrapped. Int getChildMeasureSpec(parentSize: Int, padding: Int, childDimension: Int, canScroll: Boolean) Calculate a MeasureSpec value for measuring a child view in one dimension. Int getChildMeasureSpec(parentSize: Int, parentMode: Int, padding: Int, childDimension: Int, canScroll: Boolean) Calculate a MeasureSpec value for measuring a child view in one dimension. Boolean getClipToPadding() Check if the RecyclerView is configured to clip child views to its padding. Int getColumnCountForAccessibility(@NonNull recycler: RecyclerView.Recycler, @NonNull state: RecyclerView.State) Returns the number of columns for accessibility. Default implementation returns the number of items in the adapter if LayoutManager supports horizontal scrolling or 1 if LayoutManager does not support horizontal scrolling. Int getDecoratedBottom(@NonNull child: View) Returns the bottom edge of the given child view within its parent, offset by any applied ItemDecorations. Unit getDecoratedBoundsWithMargins(@NonNull view: View, @NonNull outBounds: Rect) Returns the bounds of the view including its decoration and margins. Int getDecoratedLeft(@NonNull child: View) Returns the left edge of the given child view within its parent, offset by any applied ItemDecorations. Int getDecoratedMeasuredHeight(@NonNull child: View) Returns the measured height of the given child, plus the additional size of any insets applied by ItemDecorations. Int getDecoratedMeasuredWidth(@NonNull child: View) Returns the measured width of the given child, plus the additional size of any insets applied by ItemDecorations. Int getDecoratedRight(@NonNull child: View) Returns the right edge of the given child view within its parent, offset by any applied ItemDecorations. Int getDecoratedTop(@NonNull child: View) Returns the top edge of the given child view within its parent, offset by any applied ItemDecorations. View? getFocusedChild() Returns the item View which has or contains focus. Int getHeight() Returns the height that is currently relevant to the LayoutManager. This value is usually equal to the laid out height of the RecyclerView but may reflect the current android.view.View.MeasureSpec height if the LayoutManager is using AutoMeasure and the RecyclerView is in the process of measuring. The LayoutManager must always use this method to retrieve the height relevant to it at any given time. Int getHeightMode() Return the height measurement spec mode that is currently relevant to the LayoutManager. This value is set only if the LayoutManager opts into the AutoMeasure api via setAutoMeasureEnabled(boolean). When RecyclerView is running a layout, this value is always set to View.MeasureSpec#EXACTLY even if it was measured with a different spec mode. Int getItemCount() Returns the number of items in the adapter bound to the parent RecyclerView. Note that this number is not necessarily equal to State#getItemCount(). In methods where State is available, you should use State#getItemCount() instead. For more details, check the documentation for State#getItemCount(). Int getItemViewType(@NonNull view: View) Returns the View type defined by the adapter. Int getLayoutDirection() Returns the resolved layout direction for this RecyclerView. Int getLeftDecorationWidth(@NonNull child: View) Returns the total width of item decorations applied to child's left. Note that this value is not updated until the View is measured or calculateItemDecorationsForChild(View, Rect) is called. Int getMinimumHeight() Int getMinimumWidth() Int getPaddingBottom() Return the bottom padding of the parent RecyclerView Int getPaddingEnd() Return the end padding of the parent RecyclerView Int getPaddingLeft() Return the left padding of the parent RecyclerView Int getPaddingRight() Return the right padding of the parent RecyclerView Int getPaddingStart() Return the start padding of the parent RecyclerView Int getPaddingTop() Return the top padding of the parent RecyclerView Int getPosition(@NonNull view: View) Returns the adapter position of the item represented by the given View. This does not contain any adapter changes that might have happened after the last layout. RecyclerView.LayoutManager.Properties! getProperties(@NonNull context: Context, @Nullable attrs: AttributeSet?, defStyleAttr: Int, defStyleRes: Int) Parse the xml attributes to get the most common properties used by layout managers. android.R.attr#orientation androidx.recyclerview.R.attr#spanCount androidx.recyclerview.R.attr#reverseLayout androidx.recyclerview.R.attr#stackFromEnd Int getRightDecorationWidth(@NonNull child: View) Returns the total width of item decorations applied to child's right. Note that this value is not updated until the View is measured or calculateItemDecorationsForChild(View, Rect) is called. Int getRowCountForAccessibility(@NonNull recycler: RecyclerView.Recycler, @NonNull state: RecyclerView.State) Returns the number of rows for accessibility. Default implementation returns the number of items in the adapter if LayoutManager supports vertical scrolling or 1 if LayoutManager does not support vertical scrolling. Int getSelectionModeForAccessibility(@NonNull recycler: RecyclerView.Recycler, @NonNull state: RecyclerView.State) Returns the selection mode for accessibility. Should be AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_NONE, AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_SINGLE or AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_MULTIPLE. Default implementation returns AccessibilityNodeInfoCompat.CollectionInfoCompat#SELECTION_MODE_NONE. Int getTopDecorationHeight(@NonNull child: View) Returns the total height of item decorations applied to child's top. Note that this value is not updated until the View is measured or calculateItemDecorationsForChild(View, Rect) is called. Unit getTransformedBoundingBox(@NonNull child: View, includeDecorInsets: Boolean, @NonNull out: Rect) Calculates the bounding box of the View while taking into account its matrix changes (translation, scale etc) with respect to the RecyclerView. If includeDecorInsets is true, they are applied first before applying the View's matrix so that the decor offsets also go through the same transformation. Int getWidth() Returns the width that is currently relevant to the LayoutManager. This value is usually equal to the laid out width of the RecyclerView but may reflect the current android.view.View.MeasureSpec width if the LayoutManager is using AutoMeasure and the RecyclerView is in the process of measuring. The LayoutManager must always use this method to retrieve