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Gridview BackGround Color changing Color when Scrolling in Android

GridView item color changes randomly whenever I scroll.
Every item color is based on the status of the SQLite database, but when I tried to scroll multiple times it change the color of the item randomly. Is there any way to solve this? This is what it looks like.
Here is the code
GetView
private class ViewHolder{
ImageView imageView, mPreviewCashCard;
TextView txtName, txtPrice, txtSeriesNo;
}
#Override
public View getView(int position, View view, ViewGroup viewGroup) {
Cursor cursor = MainActivity.sqLiteHelper.getData("SELECT id,status FROM DarkMode");
while (cursor.moveToNext()) {
DarkModeStatus = cursor.getString(1);
}
View row = view;
ViewHolder holder = new ViewHolder();
if(row == null){
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(layout, null);
holder.txtName = (TextView) row.findViewById(R.id.txtName);
holder.txtPrice = (TextView) row.findViewById(R.id.txtPrice);
holder.txtSeriesNo = (TextView) row.findViewById(R.id.txtSeriesNumber);
holder.imageView = (ImageView) row.findViewById(R.id.imgFood);
holder.mPreviewCashCard = (ImageView) row.findViewById(R.id.imgId);
row.setTag(holder);
}
else {
holder = (ViewHolder) row.getTag();
}
Inventory inventory = inventoryList.get(position);
holder.txtName.setText(inventory.getName());
holder.txtPrice.setText(inventory.getPrice());
holder.txtSeriesNo.setText(inventory.getSeriesNumber());
int status = inventory.getStatus();
if (status==0 && DarkModeStatus.matches("false")){
row.setBackgroundColor(Color.parseColor("#FEF8DD"));
}
else if(status==0 && DarkModeStatus.matches("true")){
row.setBackgroundColor(Color.parseColor("#282828"));
}
byte[] CashCardImage = inventory.getImage();
byte[] idImage = inventory.getIdImage();
if(CashCardImage.length > 1)
{
Bitmap bitmap = BitmapFactory.decodeByteArray(CashCardImage, 0, CashCardImage.length);
holder.imageView.setImageBitmap(bitmap);
}
else{
holder.imageView.setImageResource(R.drawable.ic_image);
}
if(idImage.length > 1)
{
Bitmap bitmap2 = BitmapFactory.decodeByteArray(idImage, 0, idImage.length);
holder.mPreviewCashCard.setImageBitmap(bitmap2);
}
else{
holder.mPreviewCashCard.setImageResource(R.drawable.ic_image);
}
return row;
}

Try adding an else condition to your if-else block handling backgrounds.
if (status==0 && DarkModeStatus.matches("false")){
row.setBackgroundColor(Color.parseColor("#FEF8DD"));
}
else if(status==0 && DarkModeStatus.matches("true")){
row.setBackgroundColor(Color.parseColor("#282828"));
}else {
row.setBackgroundColor(Color.parseColor("#FFFFFF")); // white or whichever default background color you are using
}
From my understanding this could fix the issue.

Duplicates the Image in ListView when downloading

When the image has been downloaded, some of the images duplicates in the listview rows, even though some of the row has no ImageID, The adapter view duplicates the downloaded images, when i suddenly scroll the listview
My code in getView
public View getView(final int position, View convertView, ViewGroup parent) {
int anotherPosition = position;
if (inflater == null) {
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
final Holder holder;
if (convertView == null) {
convertView = inflater.inflate(R.layout.list_item, null);
holder = new Holder();
holder.title = (TextView) convertView.findViewById(R.id.description);
holder.exp = (TextView) convertView.findViewById(R.id.expiration);
holder.someImages = (ImageView) convertView.findViewById(R.id.listview_image);
holder.isFavouriteImage = (ImageView) convertView.findViewById(R.id.isFavourite);
convertView.setTag(holder);
convertView.setTag(R.id.listview_image, holder.someImages);
convertView.setTag(R.id.description, holder.title);
convertView.setTag(R.id.expiration, holder.exp);
convertView.setTag(R.id.isFavourite, holder.isFavouriteImage);
} else {
holder = (Holder) convertView.getTag();
}
RowItemLoyalty rowItemLoyalty = data.get(position);
if(rowItemLoyalty != null) {
holder.someImages.setTag(position);
holder.someImages.setImageBitmap(null);
holder.title.setText(data.get(position).getDescription());
holder.exp.setText(data.get(position).getDateEnd());
Log.d("TrueOrFalse", String.valueOf(holder.someImages));
if(holder.someImages != null ) {
if (data.get(position).getImageId() != 0) {
data.get(position).setBitmap(email, password, data.get(position).getImageId(), data.get(position).getBitmap(), new RowItemLoyalty.RetrieveBitmapListener() {
#Override
public void onSuccess(Bitmap bitmap) {
Log.d("ImageID123", String.valueOf(data.get(position).getImageId()));
holder.someImages.setImageBitmap(null);
if (data.get(position).getBitmap() != null) {
Log.d("True", "True");
holder.someImages.setImageBitmap(bitmap);
}
}
});
}
} else if(holder.someImages == null ) {
Drawable placeholder = ContextCompat.getDrawable(context, R.drawable.placeholderwhite);
holder.someImages.setImageDrawable(placeholder);
Log.d("PlaceHolder2", String.valueOf(placeholder));
}
//----------- placeholder for imageview list -----------
//holder.someImages.setImageBitmap(null);
if (data.get(position).getBitmap() != null && holder.someImages != null) {
holder.someImages.setImageBitmap(data.get(position).getBitmap());
Log.d("PlaceHolder", "Implemented");
Log.d("PlaceHolder", String.valueOf(data.get(position)));
} else if (data.get(position).getBitmap() == null) {
Drawable placeholder = ContextCompat.getDrawable(context, R.drawable.placeholderwhite);
holder.someImages.setImageDrawable(placeholder);
Log.d("PlaceHolder2", String.valueOf(placeholder));
}
//------------ for favourite logo-------------
if (data.get(position).getIsFavorite() == false) {
Drawable placeholderIsNotFavourite = ContextCompat.getDrawable(context, R.drawable.ic_favourite_icon);
holder.isFavouriteImage.setImageDrawable(placeholderIsNotFavourite);
} else if (data.get(position).getIsFavorite() == true) {
Drawable favourited = ContextCompat.getDrawable(context, R.drawable.favourite_two);
holder.isFavouriteImage.setImageDrawable(favourited);
}
}
return convertView;
}
My Holder class
public static class Holder {
TextView title;
TextView exp;
TextView tokensFor;
ImageView promotionImages;
ImageView isFavouriteImage;
}

There are some useful libraries you can use to loading images like Glide
Also you can see this Picasso v/s Imageloader v/s Fresco vs Glide

Try using Universal Image Loader Universal Image Loader
to set image on ImageView

Remove checking convertView == null condition, like this:
convertView = inflater.inflate(R.layout.list_item, null);
holder = new Holder();
holder.title = (TextView) convertView.findViewById(R.id.description);
holder.exp = (TextView) convertView.findViewById(R.id.expiration);
holder.someImages = (ImageView) convertView.findViewById(R.id.listview_image);
holder.isFavouriteImage = (ImageView) convertView.findViewById(R.id.isFavourite);

Android ListView getView display image randomly

I would like to display items with an adapter in a ListView but when getView is called in the ArrayAdapter, it displays the good image but not on the good item when I am scrolling. It is like if the findViewById didn't give me the good id of the layout.
public class ItemPackAdapter extends ArrayAdapter<Pack> {
Context context;
public ItemPackAdapter(Context context, ArrayList<Pack> pack) {
super(context, 0, pack);
this.context = context;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
// Check if an existing view is being reused, otherwise inflate the view
final Pack pack = getItem(position);
if (convertView == null) {
convertView = LayoutInflater.from(context).inflate(R.layout.item_pack, parent, false);
holder = new ViewHolder();
holder.textView1 = (TextView) convertView.findViewById(R.id.textView1);
holder.textView2 = (TextView) convertView.findViewById(R.id.textView2);
holder.textView3 = (TextView) convertView.findViewById(R.id.textView3);
holder.imageView = (ImageView) convertView.findViewById(R.id.imageView);
if (!pack.getImageName().equals("null")) {
UrlGenerator urlGenerator = new UrlGenerator();
String url = urlGenerator.getDownloadPicture(pack.getImageName());
DownloadPicture downloadPicture = new DownloadPicture(holder.imageView, url, getContext());
downloadPicture.start();
}
convertView.setTag(holder);
}
else {
holder = (ViewHolder)convertView.getTag();
}
holder.textView1.setText(pack.getSomething1());
holder.textView2.setText(pack.getSomething2());
holder.textView3.setText(pack.getSomething3());
if (!pack.getImageName().equals("null")) {
UrlGenerator urlGenerator = new UrlGenerator();
String url = urlGenerator.getDownloadPicture(pack.getImageName());
DownloadPicture downloadPicture = new DownloadPicture(holder.imageView, url, getContext());
downloadPicture.start();
}
if(pack.getImageName().equals("null")){
holder.imageView.setImageBitmap(null);
}
return convertView;
}
static class ViewHolder {
TextView textView1;
TextView textView2;
TextView textView3;
ImageView imageView;
}
}
Actually I found a solution with :
if(pack.getImageName().equals("null")){
holder.imageView.setImageBitmap(null);
}
But when I am scrolling on the listView, I can see the image in the wrong item, and I need to scroll again to call getView to delete the image with the previous condition.
I would like something cleaner :p
Thank you in advance.
And sorry for my bad English.

Your code looks will work just fine with just a little tweak. I discovered that you were setting the ImageView twice, so I edit your code as shown below
public class ItemPackAdapter extends ArrayAdapter<Pack> {
Context context;
ArrayList<Pack> packs;
public ItemPackAdapter(Context context, ArrayList<Pack> packs) {
super(context, 0, packs);
this.context = context;
this.packs = packs;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
// Check if an existing view is being reused, otherwise inflate the view
final Pack pack = packs.get(position);
if (convertView == null) {
convertView = LayoutInflater.from(context).inflate(R.layout.item_pack, parent, false);
holder = new ViewHolder();
holder.textView1 = (TextView) convertView.findViewById(R.id.textView1);
holder.textView2 = (TextView) convertView.findViewById(R.id.textView2);
holder.textView3 = (TextView) convertView.findViewById(R.id.textView3);
holder.imageView = (ImageView) convertView.findViewById(R.id.imageView);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
if (pack.getImageName().equals("null")) {
holder.imageView.setImageBitmap(null);
} else {
UrlGenerator urlGenerator = new UrlGenerator();
String url = urlGenerator.getDownloadPicture(pack.getImageName());
DownloadPicture downloadPicture = new DownloadPicture(holder.imageView, url, getContext());
downloadPicture.start();
}
holder.textView1.setText(pack.getSomething1());
holder.textView2.setText(pack.getSomething2());
holder.textView3.setText(pack.getSomething3());
return convertView;
}
static class ViewHolder {
TextView textView1;
TextView textView2;
TextView textView3;
ImageView imageView;
}
}

In this case if you don't caching your image that may give you like this problem.
Use Picasso library is highly recommended for avoiding this problem. Add the picasso library in your project then write your code some thing like this.
Picasso.with(getApplicationContext()).load(url).into(holder.imageView);
instead of this line
DownloadPicture downloadPicture = new DownloadPicture(holder.imageView, url, getContext());
downloadPicture.start();

Android ListView only last row on button click

I have the following code:
static class ViewHolder {
TextView camera;
TextView players;
TextView max_players;
ImageView privata;
Button Buton;
}
ViewHolder holder;
#Override
public View getView(int position, View convertView, ViewGroup parent) {
String variabile[] = getItem(position).split("\\s+");
if(convertView == null)
{
LayoutInflater linflater = LayoutInflater.from(getContext());
convertView = linflater.inflate(R.layout.custom_row, parent, false);
holder = new ViewHolder();
holder.camera = (TextView) convertView.findViewById(R.id.Nume);
holder.players = (TextView) convertView.findViewById(R.id.players);
holder.max_players = (TextView) convertView.findViewById(R.id.max_players);
holder.privata = (ImageView) convertView.findViewById(R.id.privata);
holder.Buton = (Button) convertView.findViewById(R.id.Buton);
holder.camera.setText(variabile[0]);
if (!variabile[1].equals("true")) {
parola = false;
holder.privata.setVisibility(View.INVISIBLE);
}
holder.players.setText(variabile[2]);
holder.max_players.setText(variabile[3]);
room_id = variabile[4];
nume = variabile[5];
holder.Buton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
hash = new HashMap<String, String>();
hash.put("name", nume);
hash.put("room", room_id);
if (intra) {
holder.Buton.setText("Iesi");
site = siteul + "/join";
intra = false;
} else {
holder.Buton.setText("Intra");
site = siteul + "/leave";
intra = true;
}
new ATask().execute(site);
}
});
convertView.setTag(holder);
}
else
holder = (ViewHolder) convertView.getTag();
return convertView;
}
I'm trying to access a row from an AsyncTask on PostExecute and modify it like this:
TextView players_mare = holder.players;
players_mare.setText(rez.substring(2));
No matter the button pressed it seems to modify the textview of the last item in the list.

This is happening because you are using holder. After rendering complete ListView it has reference of the last item in the ListView, so only last item is updated irrespective of the item on which button was clicked. You need to pass the reference of item in which button was clicked to the ATask class.
Add
holder.Buton.setTag(holder);
after
convertView.setTag(holder);
in getView() method
Create a class level variable in ATask clas like this
ViewHolder myHolder;
Add this in ATask
public ATask(ViewHolder view) {
myHolder = view;
}
Change ATask call like this
new ATask((ViewHolder) v.getTag()).execute(site);
In PostExecute replace every holder with myHolder

How to get view for an item in listview in android?

Is it possible to get an item view based on its position in the adapter and not in the visible views in the ListView?
I am aware of functions like getChildAt() and getItemIdAtPosition() however they provide information based on the visible views inside ListView. I am also aware that Android recycles views which means that I can only work with the visible views in the ListView.
My objective is to have a universal identifier for each item since I am using CursorAdapter so I don't have to calculate the item's position relative to the visible items.

Here's how I accomplished this. Within my (custom) adapter class:
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = null;
if (convertView == null) {
LayoutInflater inflater = context.getLayoutInflater();
view = inflater.inflate(textViewResourceId, parent, false);
final ViewHolder viewHolder = new ViewHolder();
viewHolder.name = (TextView) view.findViewById(R.id.name);
viewHolder.button = (ImageButton) view.findViewById(R.id.button);
viewHolder.button.setOnClickListener
(new View.OnClickListener() {
#Override
public void onClick(View view) {
int position = (int) viewHolder.button.getTag();
Log.d(TAG, "Position is: " +position);
}
});
view.setTag(viewHolder);
viewHolder.button.setTag(items.get(position));
} else {
view = convertView;
((ViewHolder) view.getTag()).button.setTag(items.get(position));
}
ViewHolder holder = (ViewHolder) view.getTag();
return view;
}
Essentially the trick is to set and retrieve the position index via the setTag and getTag methods. The items variable refers to the ArrayList containing my custom (adapter) objects.
Also see this tutorial for in-depth examples. Let me know if you need me to clarify anything.

See below code:
public static class ViewHolder
{
public TextView nm;
public TextView tnm;
public TextView tr;
public TextView re;
public TextView membercount;
public TextView membernm;
public TextView email;
public TextView phone;
public ImageView ii;
}
class ImageAdapter extends ArrayAdapter<CoordinatorData>
{
private ArrayList<CoordinatorData> items;
public FoodDriveImageLoader imageLoader;
public ImageAdapter(Context context, int textViewResourceId,ArrayList<CoordinatorData> items)
{
super(context, textViewResourceId, items);
this.items = items;
}
public View getView(int position, View convertView, ViewGroup parent)
{
View v = convertView;
ViewHolder holder = null;
if (v == null)
{
try
{
holder=new ViewHolder();
LayoutInflater vi = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
imageLoader = new FoodDriveImageLoader(FoodDriveModule.this);
v = vi.inflate(R.layout.virtual_food_drive_row, null);
//System.out.println("layout is null.......");
holder.nm = (TextView) v.findViewById(R.id.name);
holder.tnm = (TextView) v.findViewById(R.id.teamname);
holder.tr = (TextView) v.findViewById(R.id.target);
holder.re = (TextView) v.findViewById(R.id.received);
holder.membercount = new TextView(FoodDriveModule.this);
holder.membernm = new TextView(FoodDriveModule.this);
holder.email = new TextView(FoodDriveModule.this);
holder.phone = new TextView(FoodDriveModule.this);
holder.ii = (ImageView) v.findViewById(R.id.icon);
v.setTag(holder);
}
catch(Exception e)
{
System.out.println("Excption Caught"+e);
}
}
else
{
holder=(ViewHolder)v.getTag();
}
CoordinatorData co = items.get(position);
holder.nm.setText(co.getName());
holder.tnm.setText(co.getTeamName());
holder.tr.setText(co.getTarget());
holder.re.setText(co.getReceived());
holder.ii.setTag(co.getImage());
imageLoader.DisplayImage(co.getImage(), FoodDriveModule.this , holder.ii);
if (co != null)
{
}
return v;
}
}

A better option is to identify using the data returned by the CursorAdapter rather than visible views.
For example if your data is in a Array , each data item has a unique index.

Here, Its very short described code, you can simple re-use viewholder pattern to increase listview performance
Write below code in your getview() method
ViewHolder holder = new ViewHolder();
if (convertView == null) {
convertView = layoutInflater.inflate(R.layout.skateparklist, null);
holder = new ViewHolder();
holder.headlineView = (TextView) convertView
.findViewById(R.id.textView1);
holder.DistanceView = (TextView) convertView
.findViewById(R.id.textView2);
holder.imgview = (NetworkImageView) convertView
.findViewById(R.id.imgSkatepark);
convertView.setTag(holder); //PLEASE PASS HOLDER AS OBJECT PARAM , CAUSE YOU CAN NOY PASS POSITION IT WILL BE CONFLICT Holder and Integer can not cast
//BECAUSE WE NEED TO REUSE CREATED HOLDER
} else {
holder = (ViewHolder) convertView.getTag();
}
// your controls/UI setup
holder.DistanceView.setText(strDistance);
......
return convertview

Listview lv = (ListView) findViewById(R.id.previewlist);
final BaseAdapter adapter = new PreviewAdapter(this, name, age);
confirm.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
View view = null;
String value;
for (int i = 0; i < adapter.getCount(); i++) {
view = adapter.getView(i, view, lv);
Textview et = (TextView) view.findViewById(R.id.passfare);
value=et.getText().toString();
Toast.makeText(getApplicationContext(), value,
Toast.LENGTH_SHORT).show();
}
}
});