com.sawyer.advadapters.widget

Class SparseAdapter<T>

java.lang.Object

android.widget.BaseAdapter

com.sawyer.advadapters.widget.SparseAdapter<T>

All Implemented Interfaces:

Adapter, Filterable, ListAdapter, SpinnerAdapter

public abstract class SparseAdapter<T>
extends BaseAdapter
implements Filterable

A custom abstract BaseAdapter that is backed by a SparseArray of arbitrary objects. By default this class delegates view generation and defining the filtering logic to subclasses.

Designed to be a flexible and customizable solution for using SparseArray with an adapter. It exposes most of the SparseArray methods, provides active filtering support, and conveniently passes along a layout inflater for view creation. An adapter's row ID maps to the SparseArray's key and vice versa. Any method requiring a key will have "withId" in the name.

Because of the background filtering process, all methods which mutates the underlying data are internally synchronized. This ensures a thread safe environment for internal write operations. If filtering is not required, it's strongly recommended to use the NFSparseAdapter instead.

Field Summary

Fields inherited from interface android.widget.Adapter

IGNORE_ITEM_VIEW_TYPE, NO_SELECTION

Constructor Summary

Constructors

Constructor and Description
SparseAdapter(Context activity) Constructor
SparseAdapter(Context activity, SparseArray<T> items) Constructor

Method Summary

Modifier and Type	Method and Description
void	appendAll(SparseArray<T> items) Appends the specified SparseArray at the end of the adapter, optimizing for the case where all the keys are greater then all existing keys in the adapter.
void	appendWithId(int keyId, T item) Appends the specified key and item pair to the end of the adapter, optimizing for the case where the key is greater then all existing keys in the adapter.
void	clear() Removes all items from the adapter.
boolean	containsId(int keyId) Determines if the specified keyId exists within the adapter.
boolean	containsItem(T item) Determines if the specified item exists within the adapter.
Context	getContext()
int	getCount()
View	getDropDownView(int position, View convertView, ViewGroup parent)
View	getDropDownView(LayoutInflater inflater, int position, View convertView, ViewGroup parent) Get a View that displays in the drop down popup the data at the specified position in the data set.
Filter	getFilter()
SparseArray<T>	getFilteredSparseArray()
T	getItem(int position)
long	getItemId(int position)
T	getItemWithId(int keyId)
int	getPosition(int keyId)
int	getPosition(T item) Returns the position of the specified item in the sparse array.
SparseArray<T>	getSparseArray()
View	getView(int position, View convertView, ViewGroup parent)
abstract View	getView(LayoutInflater inflater, int position, View convertView, ViewGroup parent) Get a View that displays the data at the specified position in the data set.
void	notifyDataSetChanged()
void	put(int position, T item) Given a position in the range of 0...getCount() - 1, sets a new value for the key-value stored at that position.
void	putAll(SparseArray<T> items) Adds the specified SparseArray to the adapter, replacing any existing mappings from the specified keys if there were any.
void	putWithId(int keyId, T item) Adds the specified key and item to the adapter, replacing the previous mapping from the specified key if there was one.
void	remove(int position) Removes the mapping at the specified position in the adapter.
void	removeAll(SparseArray<T> items) Removes all items from the adapter that are found within the specified SparseArray.
void	removeWithId(int keyId) Removes the mapping with the specified keyId from the adapter.
void	setNotifyOnChange(boolean notifyOnChange) Controls whether methods that change the list (appendWithId(int, T), putWithId(int, T), remove(int), clear()) automatically call notifyDataSetChanged().
void	setSparseArray(SparseArray<T> items) Resets the adapter to store a new SparseArray of items.

Methods inherited from class android.widget.BaseAdapter

areAllItemsEnabled, getItemViewType, getViewTypeCount, hasStableIds, isEmpty, isEnabled, notifyDataSetInvalidated, registerDataSetObserver, unregisterDataSetObserver

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SparseAdapter

public SparseAdapter(Context activity)

Constructor

Parameters:

activity - Context used for inflating views

SparseAdapter

public SparseAdapter(Context activity,
                     SparseArray<T> items)

Constructor

Parameters:

activity - Context used for inflating views

items - The items to represent within the adapter.

Method Detail

appendAll

public void appendAll(SparseArray<T> items)

Appends the specified SparseArray at the end of the adapter, optimizing for the case where all the keys are greater then all existing keys in the adapter. This includes the given items having it's keys in sequential order as well. Will repeat the last filtering request if invoked while filtered results are being displayed.

Parameters:

items - The SparseArray items to add at the end of the adapter.

appendWithId

public void appendWithId(int keyId,
                         T item)

Appends the specified key and item pair to the end of the adapter, optimizing for the case where the key is greater then all existing keys in the adapter. Will repeat the last filtering request if invoked while filtered results are being displayed.

Parameters:

keyId - The keyId to append with

item - The item to append with

clear

public void clear()

Removes all items from the adapter.

containsId

public boolean containsId(int keyId)

Determines if the specified keyId exists within the adapter.

Parameters:

keyId - The keyId to search for

Returns:

true if the keyId is found within the adapter. false otherwise.

containsItem

public boolean containsItem(T item)

Determines if the specified item exists within the adapter. Be aware that this is a linear search, unlike look-ups by key, and that multiple keys can map to the same value and this will find only one of them.

Note also that unlike most collections this method compares values using == rather than equals...a result of how SparseArrays are implemented.

Parameters:

item - The item to search for

Returns:

true if the item is an element of this adapter. false otherwise

getContext

public Context getContext()

Returns:

The Context associated with this adapter.

getCount

public int getCount()

Specified by:

getCount in interface Adapter

getDropDownView

public View getDropDownView(LayoutInflater inflater,
                            int position,
                            View convertView,
                            ViewGroup parent)

Get a View that displays in the drop down popup the data at the specified position in the data set.

Parameters:

inflater - the LayoutInflater object that can be used to inflate each view.

position - index of the item whose view we want.

convertView - the old view to reuse, if possible. Note: You should check that this view is non-null and of an appropriate type before using. If it is not possible to convert this view to display the correct data, this method can create a new view.

parent - the parent that this view will eventually be attached to

Returns:

a View corresponding to the data at the specified position.

getDropDownView

public final View getDropDownView(int position,
                                  View convertView,
                                  ViewGroup parent)

Specified by:

getDropDownView in interface SpinnerAdapter

Overrides:

getDropDownView in class BaseAdapter

getFilter

public Filter getFilter()

Specified by:

getFilter in interface Filterable

getFilteredSparseArray

public SparseArray<T> getFilteredSparseArray()

Returns:

The shown filtered data as a SparseArray. If no filter is applied, then the original (unfiltered) data is returned instead.

getItem

public T getItem(int position)

Specified by:

getItem in interface Adapter

getItemId

public long getItemId(int position)

Specified by:

getItemId in interface Adapter

getItemWithId

public T getItemWithId(int keyId)

Returns:

The Item mapped by the keyId or null if no such mapping has been made

getPosition

public int getPosition(T item)

Returns the position of the specified item in the sparse array. Be aware that this is a linear search, unlike look-ups by key,and that multiple keys can map to the same value and this will find only one of them.

Note also that unlike most collections, this method compares values using == rather than equals.

Parameters:

item - The item to retrieve the position of.

Returns:

The position of the specified item, or a negative number if not found.

getPosition

public int getPosition(int keyId)

Parameters:

keyId - The keyId to search for

Returns:

the position for which a keyId is found, or a negative number if not found.

getSparseArray

public SparseArray<T> getSparseArray()

Returns:

The original (unfiltered) SparseArray of items stored within the adapter.

setSparseArray

public void setSparseArray(SparseArray<T> items)

Resets the adapter to store a new SparseArray of items. Though equivalent to calling clear(), followed by putAll(android.util.SparseArray<T>); this method is more efficient. It performs a straight clone of the items instead of having to perform a binary search before putting each item within the adapter. Will repeat the last filtering request if invoked while filtered results are being displayed.

Parameters:

items - New SparseArray of items to store within the adapter.

getView

public abstract View getView(LayoutInflater inflater,
                             int position,
                             View convertView,
                             ViewGroup parent)

Get a View that displays the data at the specified position in the data set. You can either create a View manually or inflate it from an XML layout file. When the View is inflated, the parent View (GridView, ListView...) will apply default layout parameters unless you to specifiy a root view and to prevent attachment to the root.

Parameters:

inflater - the LayoutInflater object that can be used to inflate each view.

position - The position of the item within the adapter's data set of the item whose view we want

convertView - the old view to reuse, if possible. Note: You should check that this view is non-null and of an appropriate type before using. If it is not possible to convert this view to display the correct data, this method can create a new view.

parent - the parent that this view will eventually be attached to

Returns:

A View corresponding to the data at the specified position

getView

public final View getView(int position,
                          View convertView,
                          ViewGroup parent)

Specified by:

getView in interface Adapter

notifyDataSetChanged

public void notifyDataSetChanged()

Overrides:

notifyDataSetChanged in class BaseAdapter

put

public void put(int position,
                T item)

Given a position in the range of 0...getCount() - 1, sets a new value for the key-value stored at that position. Be aware this method is only a constant amortised time operation when the adapter is not filtered. Otherwise, the position must be converted to a unfiltered position; which requires a binary search on the original unfiltered data.

Parameters:

position - The position of the item to update

item - The item to update with

putAll

public void putAll(SparseArray<T> items)

Adds the specified SparseArray to the adapter, replacing any existing mappings from the specified keys if there were any. Will repeat the last filtering request if invoked while filtered results are being displayed.

Parameters:

items - The SparseArray items to add to the adapter.

putWithId

public void putWithId(int keyId,
                      T item)

Adds the specified key and item to the adapter, replacing the previous mapping from the specified key if there was one. Will repeat the last filtering request if invoked while filtered results are being displayed.

remove

public void remove(int position)

Removes the mapping at the specified position in the adapter. Be aware this method is only a constant amortised time operation when the adapter is not filtered. Otherwise, the position must be converted to a unfiltered position; which requires a binary search on the original unfiltered sparse array.

Parameters:

position - The position of the item to remove

removeAll

public void removeAll(SparseArray<T> items)

Removes all items from the adapter that are found within the specified SparseArray.

Parameters:

items - The SparseArray items to remove from the adapter.

removeWithId

public void removeWithId(int keyId)

Removes the mapping with the specified keyId from the adapter.

Parameters:

keyId - The keyId to remove.

setNotifyOnChange

public void setNotifyOnChange(boolean notifyOnChange)

Controls whether methods that change the list (appendWithId(int, T), putWithId(int, T), remove(int), clear()) automatically call notifyDataSetChanged(). If set to false, caller must manually call notifyDataSetChanged() to have the changes reflected in the attached view.

The default is true, and calling notifyDataSetChanged() resets the flag to true.

Parameters:

notifyOnChange - if true, modifications to the list will automatically call notifyDataSetChanged()