ListRowPresenter

Kotlin |Java

open class ListRowPresenter : RowPresenter

kotlin.Any
↳	androidx.leanback.widget.Presenter
	↳	androidx.leanback.widget.RowPresenter
		↳	androidx.leanback.widget.ListRowPresenter

ListRowPresenter renders ListRow using a HorizontalGridView hosted in a ListRowView.

Hover card

Optionally, setHoverCardPresenterSelector(PresenterSelector) can be used to display a view for the currently focused list item below the rendered list. This view is known as a hover card.

Row selection animation

ListRowPresenter disables RowPresenter's default full row dimming effect and draws a dim overlay on each child individually. A subclass may disable the overlay on each child by overriding isUsingDefaultListSelectEffect() to return false and write its own child dim effect in applySelectLevelToChild(ViewHolder, View).

Shadow

ListRowPresenter applies a default shadow to each child view. Call setShadowEnabled(boolean) to disable shadows. A subclass may override and return false in isUsingDefaultShadow() and replace with its own shadow implementation.

Summary

Nested classes
open	SelectItemViewHolderTask A task on the ListRowPresenter.
open	ViewHolder ViewHolder for the ListRowPresenter.

Inherited constants

From class RowPresenter Int SYNC_ACTIVATED_CUSTOM Don't synchronize row view activated status with selected status or expanded status, application will do its own through RowPresenter.ViewHolder#setActivated(boolean). Int SYNC_ACTIVATED_TO_EXPANDED Synchronizes row view's activated status to expand status of the row view holder. Int SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED Sets the row view's activated status to true when both expand and selected are true. Int SYNC_ACTIVATED_TO_SELECTED Synchronizes row view's activated status to selected status of the row view holder.

Public constructors
<init>() Constructs a ListRowPresenter with defaults.
<init>(focusZoomFactor: Int) Constructs a ListRowPresenter with the given parameters.
<init>(focusZoomFactor: Int, useFocusDimmer: Boolean) Constructs a ListRowPresenter with the given parameters.

Public methods
Boolean	areChildRoundedCornersEnabled() Returns true if rounded corners are enabled for children of this row.
Unit	enableChildRoundedCorners(enable: Boolean) Enables or disabled rounded corners on children of this row.
open Unit	freeze(holder: RowPresenter.ViewHolder!, freeze: Boolean)
open Int	getExpandedRowHeight() Returns the expanded row height for rows created by this Presenter.
Int	getFocusZoomFactor() Returns the zoom factor used for focus highlighting.
PresenterSelector!	getHoverCardPresenterSelector() Returns the PresenterSelector used for showing a select object in a hover card.
open Int	getRecycledPoolSize(presenter: Presenter!) Returns the recycled pool size for the given presenter.
open Int	getRowHeight() Returns the row height for list rows created by this Presenter.
Boolean	getShadowEnabled() Returns true if child shadow is enabled.
Int	getZoomFactor() Returns the zoom factor used for focus highlighting.
Boolean	isFocusDimmerUsed() Returns true if the focus dimmer is used for focus highlighting; false otherwise.
Boolean	isKeepChildForeground() Returns true if keeps foreground of child of this row, false otherwise.
open Boolean	isUsingDefaultListSelectEffect() Returns true so that default select effect is applied to each individual child of HorizontalGridView.
Boolean	isUsingDefaultSelectEffect() ListRowPresenter overrides the default select effect of RowPresenter and return false.
open Boolean	isUsingDefaultShadow() Default implementation returns true if SDK version >= 21, shadow (either static or z-order based) will be applied to each individual child of HorizontalGridView.
open Boolean	isUsingOutlineClipping(context: Context!) Returns true if leanback view outline is enabled on the system or false otherwise.
open Boolean	isUsingZOrder(context: Context!) Returns true if SDK >= L, where Z shadow is enabled so that Z order is enabled on each child of horizontal list.
open Unit	setEntranceTransitionState(holder: RowPresenter.ViewHolder!, afterEntrance: Boolean)
open Unit	setExpandedRowHeight(rowHeight: Int) Sets the expanded row height for rows created by this Presenter.
Unit	setHoverCardPresenterSelector(selector: PresenterSelector!) Sets the PresenterSelector used for showing a select object in a hover card.
Unit	setKeepChildForeground(keep: Boolean) When ListRowPresenter applies overlay color on the child, it may change child's foreground Drawable.
open Unit	setNumRows(numRows: Int) Sets the numbers of rows for rendering the list of items.
open Unit	setRecycledPoolSize(presenter: Presenter!, size: Int) Sets the recycled pool size for the given presenter.
open Unit	setRowHeight(rowHeight: Int) Sets the row height for rows created by this Presenter.
Unit	setShadowEnabled(enabled: Boolean) Enables or disables child shadow.

Protected methods
open Unit	applySelectLevelToChild(rowViewHolder: ListRowPresenter.ViewHolder!, childView: View!) Applies select level to a child.
open RowPresenter.ViewHolder!	createRowViewHolder(parent: ViewGroup!)
open ShadowOverlayHelper.Options!	createShadowOverlayOptions() Create ShadowOverlayHelper Options.
open Unit	dispatchItemSelectedListener(holder: RowPresenter.ViewHolder!, selected: Boolean) Dispatch item selected event using current selected item in the HorizontalGridView.
open Unit	initializeRowViewHolder(holder: RowPresenter.ViewHolder!)
open Unit	onBindRowViewHolder(holder: RowPresenter.ViewHolder!, item: Any!)
open Unit	onRowViewExpanded(holder: RowPresenter.ViewHolder!, expanded: Boolean)
open Unit	onRowViewSelected(holder: RowPresenter.ViewHolder!, selected: Boolean)
open Unit	onSelectLevelChanged(holder: RowPresenter.ViewHolder!) Applies select level to header and draws a default color dim over each child of HorizontalGridView.
open Unit	onUnbindRowViewHolder(holder: RowPresenter.ViewHolder!)

Inherited functions
From class Presenter Unit cancelAnimationsRecursive(view: View!) Utility method for removing all running animations on a view. Any! getFacet(facetClass: Class<*>!) Unit onBindViewHolder(viewHolder: Presenter.ViewHolder!, item: Any!, payloads: MutableList<Any!>!) Binds a View to an item with a list of payloads. Unit setFacet(facetClass: Class<*>!, facetImpl: Any!) Sets dynamic implemented facet in addition to basic Presenter functions. Unit setOnClickListener(holder: Presenter.ViewHolder!, listener: OnClickListener!) Called to set a click listener for the given view holder. The default implementation sets the click listener on the root view in the view holder. If the root view isn't focusable this method should be overridden to set the listener on the appropriate focusable child view(s).
From class RowPresenter RowHeaderPresenter! getHeaderPresenter() Returns the Presenter used for rendering the header, or null if none has been set. RowPresenter.ViewHolder! getRowViewHolder(holder: Presenter.ViewHolder!) Returns the RowPresenter.ViewHolder from the given RowPresenter ViewHolder. Boolean getSelectEffectEnabled() Returns true if the row selection effect is enabled. This value not only determines whether the default dim implementation is used, but subclasses must also respect this flag. Float getSelectLevel(vh: Presenter.ViewHolder!) Returns the current select level. The value will be between 0 (unselected) and 1 (selected). Int getSyncActivatePolicy() Returns the policy of updating row view activated status. Can be one of: Default value SYNC_ACTIVATED_TO_EXPANDED SYNC_ACTIVATED_TO_SELECTED SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED SYNC_ACTIVATED_CUSTOM Boolean isClippingChildren() Returns true if the Row view should clip its children. The clipChildren flag is set on view in initializeRowViewHolder(ViewHolder). Note that Slide transition or explode transition need turn off clipChildren. Default value is false. Unit onBindViewHolder(viewHolder: Presenter.ViewHolder!, item: Any!) Presenter.ViewHolder! onCreateViewHolder(parent: ViewGroup!) Unit onRowViewAttachedToWindow(vh: RowPresenter.ViewHolder!) Invoked when the row view is attached to the window. Unit onRowViewDetachedFromWindow(vh: RowPresenter.ViewHolder!) Invoked when the row view is detached from the window. Unit onUnbindViewHolder(viewHolder: Presenter.ViewHolder!) Unit onViewAttachedToWindow(holder: Presenter.ViewHolder!) Unit onViewDetachedFromWindow(holder: Presenter.ViewHolder!) Unit setHeaderPresenter(headerPresenter: RowHeaderPresenter!) Sets the Presenter used for rendering the header. Can be null to disable header rendering. The method must be called before creating any Row Views. Unit setRowViewExpanded(holder: Presenter.ViewHolder!, expanded: Boolean) Sets the expanded state of a Row view. Unit setRowViewSelected(holder: Presenter.ViewHolder!, selected: Boolean) Sets the selected state of a Row view. Unit setSelectEffectEnabled(applyDimOnSelect: Boolean) Enables or disables the row selection effect. This will not only affect the default dim effect, but subclasses must respect this flag as well. Unit setSelectLevel(vh: Presenter.ViewHolder!, level: Float) Sets the current select level to a value between 0 (unselected) and 1 (selected). Subclasses may override onSelectLevelChanged(ViewHolder) to respond to changes in the selected level. Unit setSyncActivatePolicy(syncActivatePolicy: Int) Sets the policy of updating row view activated status. Can be one of: Default value SYNC_ACTIVATED_TO_EXPANDED SYNC_ACTIVATED_TO_SELECTED SYNC_ACTIVATED_TO_EXPANDED_AND_SELECTED SYNC_ACTIVATED_CUSTOM

Public constructors

<init>

ListRowPresenter()

Constructs a ListRowPresenter with defaults. Uses FocusHighlight#ZOOM_FACTOR_MEDIUM for focus zooming and disabled dimming on focus.

<init>

ListRowPresenter(focusZoomFactor: Int)

Constructs a ListRowPresenter with the given parameters.

Parameters
focusZoomFactor	Int: Controls the zoom factor used when an item view is focused. One of FocusHighlight#ZOOM_FACTOR_NONE, FocusHighlight#ZOOM_FACTOR_SMALL, FocusHighlight#ZOOM_FACTOR_XSMALL, FocusHighlight#ZOOM_FACTOR_MEDIUM, FocusHighlight#ZOOM_FACTOR_LARGE Dimming on focus defaults to disabled.

<init>

ListRowPresenter(
    focusZoomFactor: Int, 
    useFocusDimmer: Boolean)

Constructs a ListRowPresenter with the given parameters.

Parameters
focusZoomFactor	Int: Controls the zoom factor used when an item view is focused. One of FocusHighlight#ZOOM_FACTOR_NONE, FocusHighlight#ZOOM_FACTOR_SMALL, FocusHighlight#ZOOM_FACTOR_XSMALL, FocusHighlight#ZOOM_FACTOR_MEDIUM, FocusHighlight#ZOOM_FACTOR_LARGE
useFocusDimmer	Boolean: determines if the FocusHighlighter will use the dimmer

Public methods

areChildRoundedCornersEnabled

fun areChildRoundedCornersEnabled(): Boolean

Returns true if rounded corners are enabled for children of this row.

enableChildRoundedCorners

fun enableChildRoundedCorners(enable: Boolean): Unit

Enables or disabled rounded corners on children of this row. Supported on Android SDK >= L.

freeze

open fun freeze(
    holder: RowPresenter.ViewHolder!, 
    freeze: Boolean
): Unit

getExpandedRowHeight

open fun getExpandedRowHeight(): Int

Returns the expanded row height for rows created by this Presenter.

getFocusZoomFactor

fun getFocusZoomFactor(): Int

Returns the zoom factor used for focus highlighting.

getHoverCardPresenterSelector

fun getHoverCardPresenterSelector(): PresenterSelector!

Returns the PresenterSelector used for showing a select object in a hover card.

getRecycledPoolSize

open fun getRecycledPoolSize(presenter: Presenter!): Int

Returns the recycled pool size for the given presenter.

getRowHeight

open fun getRowHeight(): Int

Returns the row height for list rows created by this Presenter.

getShadowEnabled

fun getShadowEnabled(): Boolean

Returns true if child shadow is enabled. This is not only for enable/disable default shadow implementation but also subclass must respect this flag.

getZoomFactor

fun getZoomFactor(): Int

Deprecated: use getFocusZoomFactor instead.

Returns the zoom factor used for focus highlighting.

isFocusDimmerUsed

fun isFocusDimmerUsed(): Boolean

Returns true if the focus dimmer is used for focus highlighting; false otherwise.

isKeepChildForeground

fun isKeepChildForeground(): Boolean

Returns true if keeps foreground of child of this row, false otherwise. When ListRowPresenter applies overlay color on the child, it may change child's foreground Drawable. If application uses child's foreground for other purposes such as ripple effect, it needs tell ListRowPresenter to keep the child's foreground. The default value is true.

Return
Boolean	true if keeps foreground of child of this row, false otherwise.

isUsingDefaultListSelectEffect

open fun isUsingDefaultListSelectEffect(): Boolean

Returns true so that default select effect is applied to each individual child of HorizontalGridView. Subclass may return false to disable the default implementation and implement applySelectLevelToChild(ViewHolder, View).

See Also

• #applySelectLevelToChild(ViewHolder, View)#onSelectLevelChanged(RowPresenter.ViewHolder)

isUsingDefaultSelectEffect

fun isUsingDefaultSelectEffect(): Boolean

ListRowPresenter overrides the default select effect of RowPresenter and return false.

isUsingDefaultShadow

open fun isUsingDefaultShadow(): Boolean

Default implementation returns true if SDK version >= 21, shadow (either static or z-order based) will be applied to each individual child of HorizontalGridView. Subclass may return false to disable default implementation of shadow and provide its own.

isUsingOutlineClipping

open fun isUsingOutlineClipping(context: Context!): Boolean

Returns true if leanback view outline is enabled on the system or false otherwise. When false, rounded corner will not be enabled even enableChildRoundedCorners(boolean) is called with true.

Parameters
context	Context!: Context to retrieve system settings.

Return
Boolean	True if leanback view outline is enabled on the system or false otherwise.

isUsingZOrder

open fun isUsingZOrder(context: Context!): Boolean

Returns true if SDK >= L, where Z shadow is enabled so that Z order is enabled on each child of horizontal list. If subclass returns false in isUsingDefaultShadow() and does not use Z-shadow on SDK >= L, it should override isUsingZOrder() return false.

setEntranceTransitionState

open fun setEntranceTransitionState(
    holder: RowPresenter.ViewHolder!, 
    afterEntrance: Boolean
): Unit

setExpandedRowHeight

open fun setExpandedRowHeight(rowHeight: Int): Unit

Sets the expanded row height for rows created by this Presenter. If not set, expanded rows have the same height as unexpanded rows.

Parameters
rowHeight	Int: The row height in to use when the row is expanded, in pixels, or WRAP_CONTENT, or 0 to use the default.

setHoverCardPresenterSelector

fun setHoverCardPresenterSelector(selector: PresenterSelector!): Unit

Sets the PresenterSelector used for showing a select object in a hover card.

setKeepChildForeground

fun setKeepChildForeground(keep: Boolean): Unit

When ListRowPresenter applies overlay color on the child, it may change child's foreground Drawable. If application uses child's foreground for other purposes such as ripple effect, it needs tell ListRowPresenter to keep the child's foreground. The default value is true.

Parameters
keep	Boolean: true if keep foreground of child of this row, false ListRowPresenter might change the foreground of the child.

setNumRows

open fun setNumRows(numRows: Int): Unit

Sets the numbers of rows for rendering the list of items. By default, it is set to 1.

setRecycledPoolSize

open fun setRecycledPoolSize(
    presenter: Presenter!, 
    size: Int
): Unit

Sets the recycled pool size for the given presenter.

setRowHeight

open fun setRowHeight(rowHeight: Int): Unit

Sets the row height for rows created by this Presenter. Rows created before calling this method will not be updated.

Parameters
rowHeight	Int: Row height in pixels, or WRAP_CONTENT, or 0 to use the default height.

setShadowEnabled

fun setShadowEnabled(enabled: Boolean): Unit

Enables or disables child shadow. This is not only for enable/disable default shadow implementation but also subclass must respect this flag.

Protected methods

applySelectLevelToChild

protected open fun applySelectLevelToChild(
    rowViewHolder: ListRowPresenter.ViewHolder!, 
    childView: View!
): Unit

Applies select level to a child. Default implementation draws a default color dim over each child of HorizontalGridView. This method is called on all children in onSelectLevelChanged(RowPresenter.ViewHolder) and when a child is attached to HorizontalGridView.

Subclass may disable the default implementation by override isUsingDefaultListSelectEffect() to return false and deal with the individual item select level by itself.

Parameters
rowViewHolder	ListRowPresenter.ViewHolder!: The ViewHolder of the Row
childView	View!: The child of HorizontalGridView to apply select level.

See Also

• #isUsingDefaultListSelectEffect()RowPresenter.ViewHolder#getSelectLevel()#onSelectLevelChanged(RowPresenter.ViewHolder)

createRowViewHolder

protected open fun createRowViewHolder(parent: ViewGroup!): RowPresenter.ViewHolder!

createShadowOverlayOptions

protected open fun createShadowOverlayOptions(): ShadowOverlayHelper.Options!

Create ShadowOverlayHelper Options. Subclass may override. e.g. return new ShadowOverlayHelper.Options().roundedCornerRadius(10);

Return
ShadowOverlayHelper.Options!	The options to be used for shadow, overlay and rounded corner.

dispatchItemSelectedListener

protected open fun dispatchItemSelectedListener(
    holder: RowPresenter.ViewHolder!, 
    selected: Boolean
): Unit

Dispatch item selected event using current selected item in the HorizontalGridView. The method should only be called from onRowViewSelected().

initializeRowViewHolder

protected open fun initializeRowViewHolder(holder: RowPresenter.ViewHolder!): Unit

onBindRowViewHolder

protected open fun onBindRowViewHolder(
    holder: RowPresenter.ViewHolder!, 
    item: Any!
): Unit

onRowViewExpanded

protected open fun onRowViewExpanded(
    holder: RowPresenter.ViewHolder!, 
    expanded: Boolean
): Unit

onRowViewSelected

protected open fun onRowViewSelected(
    holder: RowPresenter.ViewHolder!, 
    selected: Boolean
): Unit

onSelectLevelChanged

protected open fun onSelectLevelChanged(holder: RowPresenter.ViewHolder!): Unit

Applies select level to header and draws a default color dim over each child of HorizontalGridView.

Subclass may override this method and starts with calling super if it has views to apply select effect other than header and HorizontalGridView. To override the default color dim over each child of HorizontalGridView, app should override isUsingDefaultListSelectEffect() to return false and override applySelectLevelToChild(ViewHolder, View).

See Also

• #isUsingDefaultListSelectEffect()RowPresenter.ViewHolder#getSelectLevel()#applySelectLevelToChild(ViewHolder, View)

onUnbindRowViewHolder

protected open fun onUnbindRowViewHolder(holder: RowPresenter.ViewHolder!): Unit