eu.davidea.flexibleadapter.items

Class AbstractFlexibleItem<VH extends RecyclerView.ViewHolder>

java.lang.Object

eu.davidea.flexibleadapter.items.AbstractFlexibleItem<VH>

Type Parameters:

VH - RecyclerView.ViewHolder

All Implemented Interfaces:

IFlexible<VH>

Direct Known Subclasses:

AbstractExpandableItem, AbstractHeaderItem, AbstractSectionableItem

public abstract class AbstractFlexibleItem<VH extends RecyclerView.ViewHolder>
extends java.lang.Object
implements IFlexible<VH>

Generic implementation of IFlexible interface with most useful methods to manage selection and view holder methods.

Since:

20/01/2016 Created
21/04/2017 ViewHolders methods are now abstract
08/12/2017 New callback methods when view is attached/detached/recycled
22/04/2018 Item is born with draggable and swipeable enabled

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	mDraggable
protected boolean	mEnabled
protected boolean	mHidden
protected boolean	mSelectable
protected boolean	mSwipeable

Constructor Summary

Constructors

Constructor and Description
AbstractFlexibleItem()

Method Summary

Modifier and Type	Method and Description
abstract void	bindViewHolder(FlexibleAdapter<IFlexible> adapter, VH holder, int position, java.util.List<java.lang.Object> payloads) Delegates the binding of this item's data to the given Layout.
abstract VH	createViewHolder(android.view.View view, FlexibleAdapter<IFlexible> adapter) Delegates the creation of the ViewHolder to the user (AutoMap).
abstract boolean	equals(java.lang.Object o) You MUST implement this method to compare items unique identifiers.
java.lang.String	getBubbleText(int position) Custom bubble text for FastScroller.
int	getItemViewType() Identifies a specific view type for this item, used by FlexibleAdapter to auto-map the ViewTypes.
abstract int	getLayoutRes() Returns the layout resource ID to auto-inflate the View for this item.
int	getSpanSize(int spanCount, int position) Individual item's span size to use only with GridLayoutManager.
boolean	isDraggable()
boolean	isEnabled() Returns if the Item is enabled.
boolean	isHidden() (Internal usage).
boolean	isSelectable() Checks if the item can be selected.
boolean	isSwipeable()
void	onViewAttached(FlexibleAdapter<IFlexible> adapter, VH holder, int position) Called when a view created by this adapter has been attached to a window.
void	onViewDetached(FlexibleAdapter<IFlexible> adapter, VH holder, int position) Called when a view created by this adapter has been detached from its window.
void	setDraggable(boolean draggable)
void	setEnabled(boolean enabled) Setter to change enabled behaviour.
void	setHidden(boolean hidden) Setter to change hidden behaviour.
void	setSelectable(boolean selectable) Setter to change selectable behaviour.
void	setSwipeable(boolean swipeable)
boolean	shouldNotifyChange(IFlexible newItem) Called by the FlexibleAdapter when it wants to check if this item should be bound again with new content.
void	unbindViewHolder(FlexibleAdapter<IFlexible> adapter, VH holder, int position) Called when a view created by this adapter has been recycled.

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

mEnabled

protected boolean mEnabled

mHidden

protected boolean mHidden

mSelectable

protected boolean mSelectable

mDraggable

protected boolean mDraggable

mSwipeable

protected boolean mSwipeable

Constructor Detail

AbstractFlexibleItem

public AbstractFlexibleItem()

Method Detail

equals

public abstract boolean equals(java.lang.Object o)

You MUST implement this method to compare items unique identifiers.

Adapter needs this method to distinguish them and pick up correct items.

See Writing a correct equals method to implement your own equals method.

Hint: If you don't use unique IDs, reimplement with Basic Java implementation:

 public boolean equals(Object o) {
     return this == o;
 }

Important Note: When used with Hash[Map,Set], the general contract for the equals and Object.hashCode() methods is that if equals returns true for any two objects, then hashCode() must return the same value for these objects. This means that subclasses of Object usually override either both methods or neither of them.

Overrides:

equals in class java.lang.Object

Parameters:

o - instance to compare

Returns:

true if items are equals, false otherwise.

isEnabled

public boolean isEnabled()

Description copied from interface: IFlexible

Returns if the Item is enabled.

Specified by:

isEnabled in interface IFlexible<VH extends RecyclerView.ViewHolder>

Returns:

(default) true for enabled item, false for disabled one.

setEnabled

public void setEnabled(boolean enabled)

Description copied from interface: IFlexible

Setter to change enabled behaviour.

Specified by:

setEnabled in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

enabled - false to disable all operations on this item

isHidden

public boolean isHidden()

Description copied from interface: IFlexible

(Internal usage). When and item has been deleted (with Undo) or has been filtered out by the adapter, then, it has hidden status.

Specified by:

isHidden in interface IFlexible<VH extends RecyclerView.ViewHolder>

Returns:

true for hidden item, (default) false for the shown one.

setHidden

public void setHidden(boolean hidden)

Description copied from interface: IFlexible

Setter to change hidden behaviour. Useful while filtering this item. Default value is false.

Specified by:

setHidden in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

hidden - true if this item should remain hidden, false otherwise

getSpanSize

public int getSpanSize(int spanCount,
                       int position)

Description copied from interface: IFlexible

Individual item's span size to use only with GridLayoutManager.

Note:

• Default implementation in AbstractFlexibleItem already returns 1.
• Not used when StaggeredGridLayoutManager is set. With such layout use FlexibleViewHolder.setFullSpan(boolean).

Specified by:

getSpanSize in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

spanCount - current column count

position - the adapter position of the item

Returns:

the number of span occupied by the item at position.

shouldNotifyChange

public boolean shouldNotifyChange(IFlexible newItem)

Description copied from interface: IFlexible

Called by the FlexibleAdapter when it wants to check if this item should be bound again with new content.

You should return true whether you want this item will be updated because its visual representations will change.

Note: This method won't be called if FlexibleAdapter.setNotifyChangeOfUnfilteredItems(boolean) is disabled.

Default value is true.

Specified by:

shouldNotifyChange in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

newItem - The new item object with the new content

Returns:

True will trigger a new binding to display new content, false if the content shown is already the latest data.

isSelectable

public boolean isSelectable()

Description copied from interface: IFlexible

Checks if the item can be selected.

Specified by:

isSelectable in interface IFlexible<VH extends RecyclerView.ViewHolder>

Returns:

(default) true for a Selectable item, false otherwise

setSelectable

public void setSelectable(boolean selectable)

Description copied from interface: IFlexible

Setter to change selectable behaviour.

Specified by:

setSelectable in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

selectable - false to disable selection on this item

getBubbleText

public java.lang.String getBubbleText(int position)

Description copied from interface: IFlexible

Custom bubble text for FastScroller.

To be called from the implementation of onCreateBubbleText(). Example:

 public String onCreateBubbleText(int position) {
     return getItem(position).getBubbleText(position);
 }

Specified by:

getBubbleText in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

position - the current mapped position

Returns:

Any desired value

isDraggable

public boolean isDraggable()

Specified by:

isDraggable in interface IFlexible<VH extends RecyclerView.ViewHolder>

setDraggable

public void setDraggable(boolean draggable)

Specified by:

setDraggable in interface IFlexible<VH extends RecyclerView.ViewHolder>

isSwipeable

public boolean isSwipeable()

Specified by:

isSwipeable in interface IFlexible<VH extends RecyclerView.ViewHolder>

setSwipeable

public void setSwipeable(boolean swipeable)

Specified by:

setSwipeable in interface IFlexible<VH extends RecyclerView.ViewHolder>

getItemViewType

public int getItemViewType()

Identifies a specific view type for this item, used by FlexibleAdapter to auto-map the ViewTypes.

HELP: To know how to implement AutoMap for ViewTypes please refer to the FlexibleAdapter Wiki Page on GitHub.

If not overridden return value is the same of getLayoutRes().

Specified by:

getItemViewType in interface IFlexible<VH extends RecyclerView.ViewHolder>

Returns:

user defined item view type identifier or layout reference if not overridden

getLayoutRes

public abstract int getLayoutRes()

Returns the layout resource ID to auto-inflate the View for this item. Optionally, you can assign same layout for multiple item types, but IFlexible.getItemViewType() must return unique values!

NOTE: Should identify a resource Layout reference R.layout.

Specified by:

getLayoutRes in interface IFlexible<VH extends RecyclerView.ViewHolder>

Returns:

layout identifier

createViewHolder

public abstract VH createViewHolder(android.view.View view,
                                    FlexibleAdapter<IFlexible> adapter)

Delegates the creation of the ViewHolder to the user (AutoMap).

HELP: To know how to implement AutoMap for ViewTypes please refer to the FlexibleAdapter Wiki Page on GitHub.

Specified by:

createViewHolder in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

view - the already inflated view

adapter - the Adapter instance extending FlexibleAdapter

Returns:

a new ViewHolder that holds a View of the given view type

bindViewHolder

public abstract void bindViewHolder(FlexibleAdapter<IFlexible> adapter,
                                    VH holder,
                                    int position,
                                    java.util.List<java.lang.Object> payloads)

Delegates the binding of this item's data to the given Layout.

HELP: To know how to implement AutoMap for ViewTypes please refer to the FlexibleAdapter Wiki Page on GitHub.

How to use Payload, please refer to RecyclerView.Adapter#onBindViewHolder(RecyclerView.ViewHolder, int, List).

Specified by:

bindViewHolder in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

adapter - the FlexibleAdapter instance

holder - the ViewHolder instance

position - the current position

payloads - a non-null list of merged payloads. Can be empty list if requires full update

unbindViewHolder

public void unbindViewHolder(FlexibleAdapter<IFlexible> adapter,
                             VH holder,
                             int position)

Called when a view created by this adapter has been recycled.

A view is recycled when a RecyclerView.LayoutManager decides that it no longer needs to be attached to its parent RecyclerView. This can be because it has fallen out of visibility or a set of cached views represented by views still attached to the parent RecyclerView.

If an item view has large or expensive data bound to it such as large bitmaps, this may be a good place to release those resources.

Specified by:

unbindViewHolder in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

adapter - the FlexibleAdapter instance

holder - the ViewHolder instance being recycled

position - the current position

onViewAttached

public void onViewAttached(FlexibleAdapter<IFlexible> adapter,
                           VH holder,
                           int position)

Called when a view created by this adapter has been attached to a window.

This can be used as a reasonable signal that the view is about to be seen by the user.

Specified by:

onViewAttached in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

adapter - the FlexibleAdapter instance

holder - the ViewHolder instance being recycled

position - the current position

onViewDetached

public void onViewDetached(FlexibleAdapter<IFlexible> adapter,
                           VH holder,
                           int position)

Called when a view created by this adapter has been detached from its window.

Becoming detached from the window is not necessarily a permanent condition; the consumer of an Adapter's views may choose to cache views offscreen while they are not visible, attaching and detaching them as appropriate.

Specified by:

onViewDetached in interface IFlexible<VH extends RecyclerView.ViewHolder>

Parameters:

adapter - the FlexibleAdapter instance

holder - the ViewHolder instance being recycled

position - the current position