Develop Reference

How to save and display items from Shared Preferences

DESCRIPTION:
I have used the concept of Shared preferences GSON concept to save/un save using "heart-icon" in list view.
My Design(fig.1)
. I can display only the titles as in Retrieved titles in a listview (fig.2) but cannot retrieve the icon of heart with titles like this figure 3.
The desired output (figure 3)
PROBLEM: I have a problem while displaying image from shared preferences in listview.
Following block of code is from CustomListAdapter::
public class CustomListAdapter extends ArrayAdapter {
private final Activity context;
private final String[] infoArray;
List<Object> selectlist = new ArrayList<Object>();
public static final String PREFERENCE_NAME = "favourite";
private final SharedPreferences sharedpreferences;
List<Object> favourites;
int[] image;
public CustomListAdapter(Activity context, String[] infoArrayParam, int[] imageIds){
super(context,R.layout.listview_row , infoArrayParam);
this.context=context;
this.infoArray = infoArrayParam;
this.image = imageIds;
sharedpreferences = context.getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
}
public View getView(final int position, View view, ViewGroup parent) {
LayoutInflater inflater = context.getLayoutInflater();
final View rowView = inflater.inflate(R.layout.listview_row, parent, false);
TextView nameTextField = (TextView) rowView.findViewById(R.id.textView2);
final ImageView imageView = (ImageView) rowView.findViewById(R.id.imageView4);
imageView.setOnClickListener(new View.OnClickListener(){
#SuppressLint({"NewApi", "ResourceType"})
#Override
public void onClick(View view) {
view.setSelected(!view.isSelected());
boolean favSelected = view.isSelected();
if (favSelected) {
imageView.setImageResource(R.drawable.ic_baseline_favorite1_24);
imageView.setTag(position);
imageView.setId(R.drawable.ic_baseline_favorite1_24);
Object chk = infoArray[position];
selectlist.add(chk);
view.setSelected(true);
saveData(context, selectlist);
}
else{
imageView.setImageResource(R.drawable.ic_baseline_favorite_border_24 );
imageView.setTag(position);
imageView.setId(R.drawable.ic_baseline_favorite_border_24);
view.setSelected(false);
removeFavorite(context,selectlist);
}
}
private boolean saveData(Context context, List<Object> selectlist){
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getContext());
SharedPreferences.Editor aSharedPreferencesEdit = sharedPreferences.edit();
Gson gson = new Gson();
String json = gson.toJson(selectlist);
aSharedPreferencesEdit.putString("task list",json);
aSharedPreferencesEdit.apply();
return false;
}
private ArrayList<Object> loadData(Context context){
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getContext());
Gson gson = new Gson();
String json = sharedPreferences.getString("task list", null);
System.out.println("The value of jsonnnnnnnn is " + json);
Type type = new TypeToken<List<Object>>(){}.getType();
System.out.println("The value of typpppppppppe is " + type);
return gson.fromJson(json, type);
}
public void removeFavorite(Context context, List<Object> selectlist) {
ArrayList<Object> favourites = loadData(context);
if (favourites != null) {
favourites.remove(selectlist);
saveData(context, favourites);
}
}
private boolean favOnClick(int position,View v, List<Object> selectlist){
ImageView button = (ImageView) v.findViewById(R.id.imageView4);
String tag = button.getTag().toString();
if (tag.equalsIgnoreCase(valueOf(position))){
saveData(context, selectlist);
button.setTag(position);
button.setImageResource(R.drawable.ic_baseline_favorite1_24);
}
else {
removeFavorite(context,selectlist);
button.setTag(position);
button.setImageResource(R.drawable.ic_baseline_favorite_border_24);
}
return true;
}
});
nameTextField.setText(infoArray[position]);
imageView.setImageResource(image[position]);
return rowView;
}
}
Following block of code is for DashBoard:
public class DashBoard extends AppCompatActivity implements BottomNavigationView.OnNavigationItemSelectedListener {
ListView listView;
Toolbar mActionBarToolBar;
Context context;
List<Object> selectlist ;
private ArrayAdapter<Object> adapter;
int[] drawableIds = new int[]{R.drawable.ic_baseline_favorite1_24, R.drawable.ic_baseline_favorite_border_24};
String[] infoArray = {
//Listed
};
protected void onCreate(Bundle savedInstanceState) {
SharedPreferences sharedPreferences = getSharedPreferences(PREFERENCE_NAME, Context.MODE_PRIVATE);
CustomListAdapter listItems = new CustomListAdapter(this, infoArray,drawableIds);
listView = (ListView) findViewById(R.id.listviewId);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) {
//To do
}
});
listView.setAdapter(listItems);
}
#RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
int id = item.getItemId();
switch (id) {
case R.id.navigation_notifications:
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
Gson gson = new Gson();
String json = sharedPreferences.getString("task list", null);
System.out.println("The value of jsonnnnnnnn is " + json);
Type type = new TypeToken<List<Object>>(){}.getType();
System.out.println("The value of typpppppppppe is " + type);
selectlist = gson.fromJson(json, type);
if (selectlist == null){
selectlist= new ArrayList<>();
}
adapter = new ArrayAdapter<Object>(DashBoard.this,
android.R.layout.simple_list_item_1, (selectlist));
listView.setAdapter(adapter);
}
return false;
}
}
REFERENCES:How to save dynamically added items in Listview with sharedpreferences?
AnyHelp will be appreciated.
Thank You.

Store and retrive Listview data using Shared Preferences

I have a listview of ringtones .. I feed the list via mysql database.. (such as song names,song urls ...).
I dynamically add products(ringtones) in my listview by adding new item in my database, so none of this data are inside my app except row icons.
This is the view
As you can see I have a bookmark border icon that when user clicks on it, it will turn into selected...This is how it works :
holder.favImage=(ImageView)v.findViewById(R.id.favImage);
holder.favImage.setImageResource(product.getFavId());
holder.favImage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Product product = (Product) mDataItems.get(position);
if(product.faved){
product.setFavId(R.mipmap.bookmarked);
sharedPreference.addFavorite(mContext,product);
product.faved=false;
}
else {
sharedPreference.removeFavorite(mContext,product);
product.setFavId(R.mipmap.bookmark_border);
product.faved = true;
}
notifyDataSetChanged();
}
});
but nothing will happen in my "FAVORITES" tab .. Even the state of bookmark icon when it is selected will not be saved..
Custom Adapter
public class FunDapter<T> extends BaseAdapter {
protected List<T> mDataItems;
protected List<T> mOrigDataItems;
protected final Context mContext;
private final int mLayoutResource;
private final BindDictionary<T> mBindDictionary;
SharedPreference sharedPreference;
public FunDapter(Context context, List<T> dataItems, int layoutResource,
BindDictionary<T> dictionary) {
this(context, dataItems, layoutResource, null, dictionary);
}
public FunDapter(Context context, List<T> dataItems, int layoutResource,
LongExtractor<T> idExtractor, BindDictionary<T> dictionary) {
this.mContext = context;
this.mDataItems = dataItems;
this.mOrigDataItems = dataItems;
this.mLayoutResource = layoutResource;
this.mBindDictionary = dictionary;
sharedPreference = new SharedPreference();
}
public void updateData(List<T> dataItems) {
this.mDataItems = dataItems;
this.mOrigDataItems = dataItems;
notifyDataSetChanged();
}
#Override
public int getCount() {
if (mDataItems == null || mBindDictionary == null) return 0;
return mDataItems.size();
}
#Override
public T getItem(int position) {
return mDataItems.get(position);
}
#Override
public long getItemId(int position) {
if(idExtractor == null) return position;
else return idExtractor.getLongValue(getItem(position), position);
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View v = convertView;
final GenericViewHolder holder;
if (null == v) {
LayoutInflater vi =
(LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = vi.inflate(mLayoutResource, null);
holder = new GenericViewHolder();
holder.root = v;
//init the sub views and put them in a holder instance
FunDapterUtils.initViews(v, holder, mBindDictionary);
v.setTag(holder);
}else {
holder = (GenericViewHolder) v.getTag();
}
final T item = getItem(position);
showData(item, holder, position);
final Product product = (Product) mDataItems.get(position);
holder.favImage=(ImageView)v.findViewById(R.id.favImage);
holder.favImage.setImageResource(product.getFavId());
holder.favImage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(product.faved){
product.setFavId(R.mipmap.bookmarked);
sharedPreference.addFavorite(mContext,product);
product.faved=false;
}
else {
sharedPreference.removeFavorite(mContext,product);
product.setFavId(R.mipmap.bookmark_border);
product.faved = true;
}
notifyDataSetChanged();
}
});
return v;
}
}
Product model class
#SuppressWarnings("serial")
public class Product implements Serializable {
#SerializedName("pid")
public int pid;
#SerializedName("name")
public String name;
#SerializedName("qty")
public int qty;
#SerializedName("price")
public String description;
#SerializedName("song_url")
public String song_url;
#SerializedName("date")
public String date;
public boolean paused = true;
public boolean faved = true;
private int favId;
public int getFavId() {
return favId;}
public void setFavId(int favId) {
this.favId = favId;}
}
SharedPreferences class
public class SharedPreference {
public static final String PREFS_NAME = "PRODUCT_APP";
public static final String FAVORITES = "Product_Favorite";
public SharedPreference() {
super();
}
// This four methods are used for maintaining favorites.
public void saveFavorites(Context context, List<Product> favorites) {
SharedPreferences settings;
Editor editor;
settings = context.getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
editor = settings.edit();
Gson gson = new Gson();
String jsonFavorites = gson.toJson(favorites);
editor.putString(FAVORITES, jsonFavorites);
editor.commit();
}
public void addFavorite(Context context, Product product) {
List<Product> favorites = getFavorites(context);
if (favorites == null)
favorites = new ArrayList<Product>();
favorites.add(product);
saveFavorites(context, favorites);
}
public void removeFavorite(Context context, Product product) {
ArrayList<Product> favorites = getFavorites(context);
if (favorites != null) {
favorites.remove(product);
saveFavorites(context, favorites);
}
}
public ArrayList<Product> getFavorites(Context context) {
SharedPreferences settings;
List<Product> favorites;
settings = context.getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
if (settings.contains(FAVORITES)) {
String jsonFavorites = settings.getString(FAVORITES, null);
Gson gson = new Gson();
Product[] favoriteItems = gson.fromJson(jsonFavorites,Product[].class);
favorites = Arrays.asList(favoriteItems);
favorites = new ArrayList<Product>(favorites);
} else
return null;
return (ArrayList<Product>) favorites;
}
}
I'm stuck here for a few days, Can you help me please !

Actually your implementation more complex for the favorite, I thing simply take one column into your database like name isFavorite and by default added zero into this column when you press button then change value zero to one but every time we are not connected with internet so use SQLite database reason behind that size and speed of the SQLite database is more compare to SharedPreferences.
But here you not want to use SQLite database so first download json from the your web service and only change made when user click on the favorite button like
Json format before click:
{unieq_id:”1”, isFavorite :”0”}
Json format after click:
{unieq_id:”1”, isFavorite :”1”}
If isFavourite 0 then your non favorite icon display else display your favorite icon.

Create favorite listview with shared preferences

I have a listview of ringtones .. I feed the list via mysql database.. (such as song names,song urls ...). I dynamically add products(ringtones) in my listview by adding new item in my database, so none of this data are inside my app except row icons.
This is the view
As you can see I have a bookmark border icon that when user clicks on it, it will turn into selected...This is how it works :
#Override
public void favOnClick(int position) {
Product product = productList.get(position);
if (product.faved) {
sharedPreference.addFavorite(activity,product);
product.setFavId(R.mipmap.bookmarked);
product.faved=false;
}else {
sharedPreference.removeFavorite(activity,product);
product.setFavId(R.mipmap.bookmark_border);
product.faved = true;
}
adapter.notifyDataSetChanged();
};
but nothing will happen in my "FAVORITES" tab .. Even the state of bookmark icon when it is selected will not be saved..
Custom Adapter
public class FunDapter<T> extends BaseAdapter {
public interface PlayPauseClick {
void favOnClick(int position);
}
private PlayPauseClick callback;
public void setPlayPauseClickListener(PlayPauseClick listener) {
this.callback = listener;
}
protected List<T> mDataItems;
protected List<T> mOrigDataItems;
protected final Context mContext;
private final int mLayoutResource;
private final BindDictionary<T> mBindDictionary;
public FunDapter(Context context, List<T> dataItems, int layoutResource,
BindDictionary<T> dictionary) {
this(context, dataItems, layoutResource, null, dictionary);
}
public FunDapter(Context context, List<T> dataItems, int layoutResource,
LongExtractor<T> idExtractor, BindDictionary<T> dictionary) {
this.mContext = context;
this.mDataItems = dataItems;
this.mOrigDataItems = dataItems;
this.mLayoutResource = layoutResource;
this.mBindDictionary = dictionary;
sharedPreference = new SharedPreference();
}
public void updateData(List<T> dataItems) {
this.mDataItems = dataItems;
this.mOrigDataItems = dataItems;
notifyDataSetChanged();
}
#Override
public int getCount() {
if (mDataItems == null || mBindDictionary == null) return 0;
return mDataItems.size();
}
#Override
public T getItem(int position) {
return mDataItems.get(position);
}
#Override
public long getItemId(int position) {
if(idExtractor == null) return position;
else return idExtractor.getLongValue(getItem(position), position);
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View v = convertView;
final GenericViewHolder holder;
if (null == v) {
LayoutInflater vi =
(LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = vi.inflate(mLayoutResource, null);
holder = new GenericViewHolder();
holder.root = v;
//init the sub views and put them in a holder instance
FunDapterUtils.initViews(v, holder, mBindDictionary);
v.setTag(holder);
}else {
holder = (GenericViewHolder) v.getTag();
}
final T item = getItem(position);
showData(item, holder, position);
Product product = (Product) mDataItems.get(position);
holder.favImage=(ImageView)v.findViewById(R.id.favImage);
holder.favImage.setImageResource(product.getFavId());
holder.favImage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (callback != null) {
callback.favOnClick(position);
}
}
});
return v;
}
}
Product model class
#SuppressWarnings("serial")
public class Product implements Serializable {
#SerializedName("pid")
public int pid;
#SerializedName("name")
public String name;
#SerializedName("qty")
public int qty;
#SerializedName("price")
public String description;
#SerializedName("song_url")
public String song_url;
#SerializedName("date")
public String date;
public boolean paused = true;
public boolean faved = true;
private int favId;
public int getFavId() {
return favId;}
public void setFavId(int favId) {
this.favId = favId;}
}
SharedPreferences class
public class SharedPreference {
public static final String PREFS_NAME = "PRODUCT_APP";
public static final String FAVORITES = "Product_Favorite";
public SharedPreference() {
super();
}
// This four methods are used for maintaining favorites.
public void saveFavorites(Context context, List<Product> favorites) {
SharedPreferences settings;
Editor editor;
settings = context.getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
editor = settings.edit();
Gson gson = new Gson();
String jsonFavorites = gson.toJson(favorites);
editor.putString(FAVORITES, jsonFavorites);
editor.commit();
}
public void addFavorite(Context context, Product product) {
List<Product> favorites = getFavorites(context);
if (favorites == null)
favorites = new ArrayList<Product>();
favorites.add(product);
saveFavorites(context, favorites);
}
public void removeFavorite(Context context, Product product) {
ArrayList<Product> favorites = getFavorites(context);
if (favorites != null) {
favorites.remove(product);
saveFavorites(context, favorites);
}
}
public ArrayList<Product> getFavorites(Context context) {
SharedPreferences settings;
List<Product> favorites;
settings = context.getSharedPreferences(PREFS_NAME,Context.MODE_PRIVATE);
if (settings.contains(FAVORITES)) {
String jsonFavorites = settings.getString(FAVORITES, null);
Gson gson = new Gson();
Product[] favoriteItems = gson.fromJson(jsonFavorites,Product[].class);
favorites = Arrays.asList(favoriteItems);
favorites = new ArrayList<Product>(favorites);
} else
return null;
return (ArrayList<Product>) favorites;
}
}
I'm stuck here for a few days, Can you help me please !
This is my project link if you would like to look into it for further info
http://symphonyrecords.ir/RingtoneApp.rar

There are two problems here (based on your project)
First (saving state of bookmark Imageview)
In adapter create a method that checks whether a particular product exists in SharedPreferences
public boolean checkFavoriteItem(Product checkProduct) {
boolean check = false;
List<Product> favorites = sharedPreference.getFavorites(null, mContext);
if (favorites != null) {
for (Product product : favorites) {
if (product.equals(checkProduct)) {
check = true;
break;
}
}
}
return check;
}
Inside adapter check if a product exists in shared preferences then set bookmarked drawable and set a tag
if (checkFavoriteItem(product)) {
holder.favoriteImg.setImageResource(R.mipmap.bookmarked);
holder.favoriteImg.setTag("bookmarked");
} else {
holder.favoriteImg.setImageResource(R.mipmap.bookmark_border);
holder.favoriteImg.setTag("bookmark_border");
}
Then inside favOnClick callback method
#Override
public boolean favOnClick(int position ,View v) {
Product product = (Product) productList.get(position);
ImageView button = (ImageView) v.findViewById(R.id.favImage);
String tag = button.getTag().toString();
if (tag.equalsIgnoreCase("bookmark_border")) {
sharedPreference.addFavorite(activity,product);
Toast.makeText(activity,"Added to Favorites",Toast.LENGTH_SHORT).show();
button.setTag("bookmarked");
button.setImageResource(R.mipmap.bookmarked);
} else {
sharedPreference.removeFavorite(activity,product);
button.setTag("bookmark_border");
button.setImageResource(R.mipmap.bookmark_border);
Toast.makeText(activity,"Removed from Favorites",Toast.LENGTH_SHORT).show();
}
return true;
}
Second (get favorite product and pass it to "FAVORITE" Fragment)
Inside getFavorite method add a String parameter
Then in your "FAVORITE" Fragment with processFinish(your AsyncResponse) call your getFavorite in order to get your Favorite product list then set your adapter :
Context mContext;
`mContext = getContext();`
#Override
public void processFinish(String s) {
productList = sharedPreference.getFavorites(s, mContext);
BindDictionary<Product> dict = new BindDictionary<Product>();
dict.addStringField(R.id.tvName, new StringExtractor<Product>() {
#Override
public String getStringValue(Product product, int position) {
return product.name;
}
});
dict.addStringField(R.id.tvDescription, new StringExtractor<Product>() {
#Override
public String getStringValue(Product product, int position) {
return product.description;
}
});
dict.addStringField(R.id.tvQty, new StringExtractor<Product>() {
#Override
public String getStringValue(Product product, int position) {
return "" + product.qty;
}
});
adapter = new FunDapter<>(getActivity(), productList, R.layout.d_layout_list_d, dict);
lvProduct.setAdapter(adapter);
}

Make sure favOnClick method change the object in FunDapter.mDataItems.
So, Change the callback method:
#Override
public void favOnClick(int position) {
Product product = adapter.get(position);
if (product.faved) {
sharedPreference.addFavorite(activity, product);
product.setFavId(R.mipmap.bookmarked);
product.faved=false;
}else {
sharedPreference.removeFavorite(activity, product);
product.setFavId(R.mipmap.bookmark_border);
product.faved = true;
}
adapter.notifyDataSetChanged();
};

Check this, 99% working code
On click Fav Btn
List< RvModel > favorites_list = storageFavorites.loadFavourite();
boolean exist = false;
if (favorites_list == null) {
favorites_list = new ArrayList<>();
}
for (int i = 0; i < favorites_list.size(); i++) {
if (favorites_list.get(i).getId().equals(rvModelArrayList.get(position).getId())) {
exist = true;
}
}
if (!exist) {
ArrayList< RvModel > audios = new ArrayList< RvModel >(favorites_list);
audios.add(rvModelArrayList.get(position));
storageFavorites.storeImage(audios);
holder.bookMarkBtn.setImageDrawable(activity.getResources().getDrawable(R.drawable.ic_bookmark_full));
} else {
ArrayList< RvModel > new_favorites = new ArrayList< RvModel >();
for (int i = 0; i < favorites_list.size(); i++) {
if (!favorites_list.get(i).getId().equals(rvModelArrayList.get(position).getId())) {
new_favorites.add(favorites_list.get(i));
}
}
if (favorites) {
Log.v("DOWNLOADED", "favorites==true");
rvModelArrayList.remove(position);
notifyDataSetChanged();
//holder.ripple_view_wallpaper_item.setVisibility(View.GONE);
}
storageFavorites.storeImage(new_favorites);
holder.bookMarkBtn.setImageDrawable(activity.getResources().getDrawable(R.drawable.ic_bookmark));
}
}

Adding favorite button in list view

I have a listview which has a favorite button for every list item which when clicked should add the list item to another activity called my fav9rites. I am using a Baseadapter for the listview and Sharedpreference for adding favorites.
When I click the favorite button, the list view item is getting added in the my favorites activity but I am facing the following problems:
1)the favorite button when clicked should turn dark indicating that the list item is added to favorites. This happens but when I close the activity and come back again the button reverts back instead of being dark
2)on long press on list item in my favorites activity , the list item should be removed from the favorites but this is not happening.
Hope everyone understand my question
My code
my base adapter
public View getView(final int position, View view, ViewGroup parent)
{
final ViewHolder holder;
if(view == null){
holder = new ViewHolder();
view = inflater.inflate(R.layout.beg_list_item,null);
holder.listHeading = (TextView) view.findViewById(R.id.beg_list_itemTextView);
// holder.listHash = (TextView) view.findViewById(R.id.listview_hashtags);
holder.alphabetList = (ImageView) view.findViewById(R.id.beg_list_itemImageView);
holder.favoriteImg = (ImageView) view.findViewById(R.id.favbtn);
view.setTag(holder);
}else{
holder = (ViewHolder) view.getTag();
}
CodeList code = (CodeList) getItem(position);
holder.listHeading.setText(codeList.get(position).getListHeading());
imageLoader.DisplayImage(codeList.get(position).getAlphabetimg(),
holder.alphabetList);
// holder.listHash.setText(codeList.get(position).getListHashTags());
if (checkFavoriteItem(code)) {
holder.favoriteImg.setImageResource(R.drawable.favorite);
holder.favoriteImg.setTag("yes");
} else {
holder.favoriteImg.setImageResource(R.drawable.unfavorite);
holder.favoriteImg.setTag("no");
}
view.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View arg0){
Intent intent = new Intent(context, SingleItemView.class);
//intent.putExtra("listheading",
// (codeList.get(position).getListHeading()));
//intent.putExtra("alphabetimg",
// (codeList.get(position).getAlphabetimg()));
intent.putExtra("demovideo",
(codeList.get(position).getDailogdemovideo()));
intent.putExtra("download",
(codeList.get(position).getDownloadCode()));
// Start SingleItemView Class
context.startActivity(intent);
}
});
final ImageView favoritesbutton = (ImageView) view.findViewById(R.id.favbtn);
favoritesbutton.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View v){
String tag = favoritesbutton.getTag().toString();
if(tag.equalsIgnoreCase("no")){
shrdPrefence.addFavorite(context, codeList.get(position));
Toast.makeText(context, R.string.fav_added, Toast.LENGTH_SHORT).show();
favoritesbutton.setTag("yes");
favoritesbutton.setImageResource(R.drawable.favorite);
}else{
shrdPrefence.removeFavorite(context, codeList.get(position));
favoritesbutton.setTag("no");
favoritesbutton.setImageResource(R.drawable.unfavorite);
Toast.makeText(context, R.string.fav_removed, Toast.LENGTH_SHORT).show();
}
}
});
return view;
}
//Checks whether a particular product exists in SharedPreferences*/
public boolean checkFavoriteItem(CodeList checkCode) {
boolean check = false;
List<CodeList> favorites = shrdPrefence.getFavorites(context);
if (favorites != null) {
for (CodeList code : favorites) {
if (code.equals(checkCode)) {
check = true;
break;
}
}
}
return check;
}
public void add(CodeList code) {
codeList.add(code);
notifyDataSetChanged();
}
public void remove(CodeList code) {
codeList.remove(code);
notifyDataSetChanged();
}
sharedpreference.java
public class SharedPreference
{
public static final String PREFS_NAME = "MY_APP";
public static final String FAVORITES = "code_Favorite";
public SharedPreference(){
super();
}
public void saveFavorites(Context context, List<CodeList> favorites){
SharedPreferences settings;
Editor editor;
settings = context.getSharedPreferences(PREFS_NAME,
Context.MODE_PRIVATE);
editor = settings.edit();
Gson gson = new Gson();
String jsonFavorites = gson.toJson(favorites);
editor.putString(FAVORITES, jsonFavorites);
editor.commit();
}
public void addFavorite(Context context, CodeList code){
List<CodeList> favorites = getFavorites(context);
if(favorites == null)
favorites = new ArrayList<CodeList>();
favorites.add(code);
saveFavorites(context,favorites);
}
public void removeFavorite(Context context, CodeList code) {
ArrayList<CodeList> favorites = getFavorites(context);
if (favorites != null) {
favorites.remove(code);
saveFavorites(context, favorites);
}
}
public ArrayList<CodeList> getFavorites(Context context) {
SharedPreferences settings;
List<CodeList> favorites;
settings = context.getSharedPreferences(PREFS_NAME,
Context.MODE_PRIVATE);
if (settings.contains(FAVORITES)) {
String jsonFavorites = settings.getString(FAVORITES, null);
Gson gson = new Gson();
CodeList[] favoriteItems = gson.fromJson(jsonFavorites,
CodeList[].class);
favorites = Arrays.asList(favoriteItems);
favorites = new ArrayList<CodeList>(favorites);
} else
return null;
return (ArrayList<CodeList>) favorites;
}
}
my favorite..java
public class MyFavActivity extends Activity
{
SharedPreference shrdPrfence;
List<CodeList> favorites;
FinalAdapter fnlAdpter;
Context context = this.context;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.fav_layout);
shrdPrfence = new SharedPreference();
favorites = shrdPrfence.getFavorites(MyFavActivity.this);
if(favorites == null){
Dialog dialog = new Dialog(MyFavActivity.this);
dialog.setTitle(R.string.nofav_title);
dialog.show();
}else{
if(favorites.size() == 0){
Dialog dialog = new Dialog(MyFavActivity.this);
dialog.setTitle(R.string.nofav_title);
dialog.show();
}
ListView favList = (ListView) findViewById(R.id.fav_layoutListView);
if(favorites != null){
fnlAdpter = new FinalAdapter(MyFavActivity.this, favorites);
favList.setAdapter(fnlAdpter);
favList.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View arg1,
int position, long arg3) {
}
});
favList.setOnItemLongClickListener(new OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> parent, View view,
int position, long id) {
ImageView button = (ImageView) view
.findViewById(R.id.favbtn);
String tag = button.getTag().toString();
if (tag.equalsIgnoreCase("no")) {
shrdPrfence.addFavorite(MyFavActivity.this,
favorites.get(position));
Toast.makeText(
MyFavActivity.this,
R.string.fav_added,
Toast.LENGTH_SHORT).show();
button.setTag("yes");
button.setImageResource(R.drawable.favorite);
} else {
shrdPrfence.removeFavorite(MyFavActivity.this,
favorites.get(position));
button.setTag("no");
button.setImageResource(R.drawable.unfavorite);
fnlAdpter.remove(favorites.get(position));
Toast.makeText(
MyFavActivity.this,
R.string.fav_removed,
Toast.LENGTH_SHORT).show();
}
return true;
}
});
}
}
}
}

Actually your saveFavorites() method works fine, becuse you just call gson.toJson() ( convert everything in json format)
You want to get saved data with SharedPreferences and you have used this line to retrieve your data
gson.fromJson(jsonFavorites, CodeList[].class);
you never get your saved data with this line, because you save a list and you want to retrieve an array (!)
If you saved a list you must retrive your data with a list token. And you need this line
gson.fromJson(jsonFavorites,new TypeToken<ArrayList<CodeList>>() {}.getType());
I think this will solve your question. Good luck.

Adding favorites in list view using shared preferences

My app has a lost view and every listitem has a favorite button which when clicked should save the list item and save it in shared preferences. All the favorites list items should be displayed in another my favorites activity and when the list item from my favorites activity is long press it should be removed from favorites. When the favorites button is clicked it should turn dark indicating its added to favorites . in my case
1) when list item is added to favorites the favorites button turn dark but when the activity is closed and reopened the button is no longer dark
2)the list items are getting added to my favorites activity but on long press are not getting removed
sharedpreference.java
public class SharedPreference
{
public static final String PREFS_NAME = "MY_APP";
public static final String FAVORITES = "code_Favorite";
public SharedPreference(){
super();
}
public void saveFavorites(Context context, List<CodeList> favorites){
SharedPreferences settings;
Editor editor;
settings = context.getSharedPreferences(PREFS_NAME,
Context.MODE_PRIVATE);
editor = settings.edit();
Gson gson = new Gson();
String jsonFavorites = gson.toJson(favorites);
editor.putString(FAVORITES, jsonFavorites);
editor.commit();
}
public void addFavorite(Context context, CodeList code){
List<CodeList> favorites = getFavorites(context);
if(favorites == null)
favorites = new ArrayList<CodeList>();
favorites.add(code);
saveFavorites(context,favorites);
}
public void removeFavorite(Context context, CodeList code) {
ArrayList<CodeList> favorites = getFavorites(context);
if (favorites != null) {
favorites.remove(code);
saveFavorites(context, favorites);
}
}
public ArrayList<CodeList> getFavorites(Context context) {
SharedPreferences settings;
List<CodeList> favorites;
settings = context.getSharedPreferences(PREFS_NAME,
Context.MODE_PRIVATE);
if (settings.contains(FAVORITES)) {
String jsonFavorites = settings.getString(FAVORITES, null);
Gson gson = new Gson();
CodeList[] favoriteItems = gson.fromJson(jsonFavorites,
CodeList[].class);
favorites = Arrays.asList(favoriteItems);
favorites = new ArrayList<CodeList>(favorites);
} else
return null;
return (ArrayList<CodeList>) favorites;
}
}
my base adapter
public View getView(final int position, View view, ViewGroup parent)
{
final ViewHolder holder;
if(view == null){
holder = new ViewHolder();
view = inflater.inflate(R.layout.beg_list_item,null);
holder.listHeading = (TextView) view.findViewById(R.id.beg_list_itemTextView);
// holder.listHash = (TextView) view.findViewById(R.id.listview_hashtags);
holder.alphabetList = (ImageView) view.findViewById(R.id.beg_list_itemImageView);
holder.favoriteImg = (ImageView) view.findViewById(R.id.favbtn);
view.setTag(holder);
}else{
holder = (ViewHolder) view.getTag();
}
CodeList code = (CodeList) getItem(position);
holder.listHeading.setText(codeList.get(position).getListHeading());
imageLoader.DisplayImage(codeList.get(position).getAlphabetimg(),
holder.alphabetList);
// holder.listHash.setText(codeList.get(position).getListHashTags());
if (checkFavoriteItem(code)) {
holder.favoriteImg.setImageResource(R.drawable.favorite);
holder.favoriteImg.setTag("yes");
} else {
holder.favoriteImg.setImageResource(R.drawable.unfavorite);
holder.favoriteImg.setTag("no");
}
view.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View arg0){
Intent intent = new Intent(context, SingleItemView.class);
//intent.putExtra("listheading",
// (codeList.get(position).getListHeading()));
//intent.putExtra("alphabetimg",
// (codeList.get(position).getAlphabetimg()));
intent.putExtra("demovideo",
(codeList.get(position).getDailogdemovideo()));
intent.putExtra("download",
(codeList.get(position).getDownloadCode()));
// Start SingleItemView Class
context.startActivity(intent);
}
});
final ImageView favoritesbutton = (ImageView) view.findViewById(R.id.favbtn);
favoritesbutton.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View v){
String tag = favoritesbutton.getTag().toString();
if(tag.equalsIgnoreCase("no")){
shrdPrefence.addFavorite(context, codeList.get(position));
Toast.makeText(context, R.string.fav_added, Toast.LENGTH_SHORT).show();
favoritesbutton.setTag("yes");
favoritesbutton.setImageResource(R.drawable.favorite);
}else{
shrdPrefence.removeFavorite(context, codeList.get(position));
favoritesbutton.setTag("no");
favoritesbutton.setImageResource(R.drawable.unfavorite);
Toast.makeText(context, R.string.fav_removed, Toast.LENGTH_SHORT).show();
}
}
});
return view;
}
//Checks whether a particular product exists in SharedPreferences*/
public boolean checkFavoriteItem(CodeList checkCode) {
boolean check = false;
List<CodeList> favorites = shrdPrefence.getFavorites(context);
if (favorites != null) {
for (CodeList code : favorites) {
if (code.equals(checkCode)) {
check = true;
break;
}
}
}
return check;
}
public void add(CodeList code) {
codeList.add(code);
notifyDataSetChanged();
}
public void remove(CodeList code) {
codeList.remove(code);
notifyDataSetChanged();
}
my favorite..java
public class MyFavActivity extends Activity
{
SharedPreference shrdPrfence;
List<CodeList> favorites;
FinalAdapter fnlAdpter;
Context context = this.context;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.fav_layout);
shrdPrfence = new SharedPreference();
favorites = shrdPrfence.getFavorites(MyFavActivity.this);
if(favorites == null){
Dialog dialog = new Dialog(MyFavActivity.this);
dialog.setTitle(R.string.nofav_title);
dialog.show();
}else{
if(favorites.size() == 0){
Dialog dialog = new Dialog(MyFavActivity.this);
dialog.setTitle(R.string.nofav_title);
dialog.show();
}
ListView favList = (ListView) findViewById(R.id.fav_layoutListView);
if(favorites != null){
fnlAdpter = new FinalAdapter(MyFavActivity.this, favorites);
favList.setAdapter(fnlAdpter);
favList.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View arg1,
int position, long arg3) {
}
});
favList.setOnItemLongClickListener(new OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> parent, View view,
int position, long id) {
ImageView button = (ImageView) view
.findViewById(R.id.favbtn);
String tag = button.getTag().toString();
if (tag.equalsIgnoreCase("no")) {
shrdPrfence.addFavorite(MyFavActivity.this,
favorites.get(position));
Toast.makeText(
MyFavActivity.this,
R.string.fav_added,
Toast.LENGTH_SHORT).show();
button.setTag("yes");
button.setImageResource(R.drawable.favorite);
} else {
shrdPrfence.removeFavorite(MyFavActivity.this,
favorites.get(position));
button.setTag("no");
button.setImageResource(R.drawable.unfavorite);
fnlAdpter.remove(favorites.get(position));
Toast.makeText(
MyFavActivity.this,
R.string.fav_removed,
Toast.LENGTH_SHORT).show();
}
return true;
}
});
}
}
}
}
codelist.java
public class CodeList
{
private String description;
private String dailogdemovideo;
private String downloadCode;
public void setDailogdemovideo(String dailogdemovideo)
{
this.dailogdemovideo = dailogdemovideo;
}
public String getDailogdemovideo()
{
return dailogdemovideo;
}
public void setDownloadCode(String downloadCode)
{
this.downloadCode = downloadCode;
}
public String getDownloadCode()
{
return downloadCode;
}
public void setDescription(String description)
{
this.description = description;
}
public String getDescription()
{
return description;
}
}