Develop Reference

GetView not called on notifyDataSetChanged, ListView is stuck

I have a problem, I have created custom adapter with custom filtering on Contact object in Contacts app, it filters names of contacts just fine and list of filteredContacts is saved properly. The problem is that when I type anything in searchView, the number of found rows is correct but informations about found rows are not correct. The problem seems to be about getView function in adapter, it is not called when it should. For example if i have three contacts: "abc", "aaa", "aba" and they are shown at the beggining in this order from top to bottom, then if I type "ab" in searchView then it finds 2 rows but they are still the same as at the beggining, they should be "abc" and "aba" but they are "abc" and "aaa". The first ever view created by adapter seems to be stuck for some reason.
My activity class:
package com.example.androidlab;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import androidx.appcompat.app.AppCompatActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.Toast;
import java.lang.reflect.Type;
import java.util.ArrayList;
public class AllContactsActivity extends AppCompatActivity {
static ArrayList<Contact> contacts = new ArrayList<>();
ContactsAdapter contactsAdapter;
ListView listView;
SearchView searchView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_all_contacts);
FloatingActionButton addContact = findViewById(R.id.newContact);
listView = findViewById(R.id.allContactsList);
searchView = findViewById(R.id.searchContacts);
SharedPreferences sharedPreferences = getApplicationContext().getSharedPreferences("com.tanay.thunderbird.contacts", Context.MODE_PRIVATE);
Gson gson = new Gson();
String json = sharedPreferences.getString("contacts", null);
Type type = new TypeToken<ArrayList<Contact>>() {
}.getType();
contacts = gson.fromJson(json, type);
if (contacts == null) {
contacts = new ArrayList<>();
}
if (contacts.size() == 0)
Toast.makeText(this, "There are no contacts.", Toast.LENGTH_LONG).show();
contactsAdapter = new ContactsAdapter(this, contacts);
listView.setAdapter(contactsAdapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent = new Intent(getApplicationContext(), EditContactActivity.class);
intent.putExtra("noteID", position);
startActivity(intent);
finish();
}
});
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String query) {
contactsAdapter.getFilter().filter(query);
return false;
}
#Override
public boolean onQueryTextChange(String query) {
contactsAdapter.getFilter().filter(query);
return false;
}
});
addContact.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getApplicationContext(), NewContactActivity.class);
startActivity(intent);
finish();
}
});
}
#Override
public void onBackPressed() {
finish();
}
}
My adapter class:
package com.example.androidlab;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Base64;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;
public class ContactsAdapter extends BaseAdapter implements Filterable {
Context context;
List<Contact> contacts;
List<Contact> filteredContacts;
ContactFilter mFilter = new ContactFilter();
String filterString;
ContactsAdapter(Context context, List<Contact> contacts) {
this.context = context;
this.contacts = contacts;
filteredContacts = contacts;
}
#Override
public int getCount() {
if(contacts.size() != filteredContacts.size() || filterString != null)
{
return filteredContacts.size();
}
else {
filteredContacts = contacts;
return contacts.size();
}
}
#Override
public Object getItem(int position) {
return contacts.get(position);
}
#Override
public long getItemId(int position) {
return contacts.indexOf(getItem(position));
}
#Override
public Filter getFilter() {
return mFilter;
}
private class ViewHolder {
ImageView imageView;
TextView name;
TextView phoneNumber;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
LayoutInflater mInflater = (LayoutInflater) context.getSystemService(AllContactsActivity.LAYOUT_INFLATER_SERVICE);
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_contacts, null);
holder = new ViewHolder();
holder.name = (TextView) convertView.findViewById(R.id.contactName);
holder.imageView = (ImageView) convertView.findViewById(R.id.imageOfContact);
holder.phoneNumber = (TextView) convertView.findViewById(R.id.phoneNumber);
Contact contact;
if(filteredContacts.size() != contacts.size()) contact = filteredContacts.get(position);
else contact = contacts.get(position);
if (contact.getAvatar() == null) {
if (contact.getGender() == true)
holder.imageView.setImageResource(R.drawable.ic_man);
else holder.imageView.setImageResource(R.drawable.ic_woman);
} else {
byte[] decodedString = Base64.decode(contact.getAvatar(), Base64.DEFAULT);
Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);
holder.imageView.setImageBitmap(decodedByte);
}
holder.name.setText(contact.getName());
holder.phoneNumber.setText(String.valueOf(contact.getPhoneNumber()));
}
return convertView;
}
private class ContactFilter extends Filter {
#Override
protected FilterResults performFiltering(CharSequence constraint) {
filterString = constraint.toString().toLowerCase();
FilterResults results = new FilterResults();
final List<Contact> list = contacts;
int count = list.size();
final ArrayList<Contact> nList = new ArrayList<Contact>();
for (int i = 0; i < count; i++) {
if(contacts.get(i).getName().contains(filterString)) nList.add(contacts.get(i));
}
results.values = nList;
results.count = nList.size();
return results;
}
#SuppressWarnings("unchecked")
#Override
protected void publishResults(CharSequence constraint, FilterResults results) {
filteredContacts = (ArrayList<Contact>) results.values;
notifyDataSetChanged();
}
}
}
EDIT: I got rid of if(contentView == null) in getView function and everything works fine

The check for convertView == null should only handle the inflation of your View and the creation of a new ViewHolder the rest of you getView code should always run.
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.list_contacts, null);
// attach a new holder to the inflated view
holder = new ViewHolder();
convertView.setTag(holder);
} else {
// get an existing holder from the existing view
holder = (ViewHolder) convertView.getTag();
}
// update your holder here:
// e.g. holder.name.setText(contact.getName());
return convertView;
}

Why my listview not refresh when I press back button and come back to activity?

I'm tired already with my code. I'm writing chat application. My app consist of two activity. First activity has a listview of wich each row contain a last message which was send for the user while a second activity contain the whole conversation. In my app I used socket.io for android. My app works fine. Listview is refresh when a data is receive but when I press back button and then come back to the activity a listview not refresh itself already. In logs console I see that a data has received and "changed" method is called but listview is not refresh. What is wrong in belows code?
package com.example.seadog.fb_dialog;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Typeface;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.TextView;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.net.URISyntaxException;
import java.util.ArrayList;
import io.socket.client.IO;
import io.socket.client.Socket;
import io.socket.emitter.Emitter;
public class MainActivity extends Activity {
public static ArrayList arrayList = new ArrayList();
public ListView listView;
public MyBaseAdapter adapter;
public TextView textView;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/*
* Get Socket.io Object
*/
SocketIO socketIo = new SocketIO();
Socket mSocket = socketIo.getSocket(); // get socket
Integer id = socketIo.getId(); // get Website ID
if(mSocket == null) {
socketIo.Connection();
mSocket = socketIo.getSocket();
mSocket.on("message", new Emitter.Listener() {
/*
* Message Listener
*/
#Override
public void call(Object... args) {
Boolean isset = false;
try {
JSONObject object = (JSONObject) args[0];
String _id = object.getString("_id");
String message = object.getString("message");
JSONObject obj = new JSONObject();
obj.put("direction", "fb-lt");
obj.put("message", message);
obj.put("date", "2017-05-29T12:15:49.245Z");
for(int i = 0; i < arrayList.size(); i++){
ListData ld = (ListData) arrayList.get(i);
String id = ld.getId();
if(_id.equals(id)){
JSONArray Data = ld.getData();
Data.put(obj);
ld.setDescription(message);
arrayList.set(i, ld);
isset = true;
Log.d("LOG", message);
}
}
if(!isset) {
JSONArray jsonArray = new JSONArray();
jsonArray.put(obj);
ListData ld = new ListData();
ld.set_id(_id);
ld.setID(1);
ld.setTitle("Klient:");
ld.setDescription(message);
ld.setData(jsonArray);
arrayList.add(ld);
}
} catch (JSONException e) {
e.printStackTrace();
}
changed();
}
});
}
/*
* Populate a listview
*/
listView = (ListView) findViewById(R.id.listView);
adapter = new MyBaseAdapter(this, arrayList);
listView.setAdapter(adapter);
/*
* OnItemClickListener
*/
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent = new Intent(MainActivity.this, Conversation.class);
intent.putExtra("item", position);
startActivity(intent);
TextView textView = (TextView) view.findViewById(R.id.descitem);
textView.setTypeface(null, Typeface.NORMAL);
}
});
textView = (TextView) findViewById(R.id.count);
}
private void changed() {
runOnUiThread(new Runnable() {
#Override
public void run() {
adapter.notifyDataSetChanged();
Log.d("LOG:", "adapter refresh");
}
});
}
}
MyBaseAdapter Class:
package com.example.seadog.fb_dialog;
import android.content.Context;
import android.graphics.Typeface;
import android.util.Log;
import android.util.TypedValue;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
import java.util.ArrayList;
public class MyBaseAdapter extends BaseAdapter {
Context context;
ArrayList<ListData> items = new ArrayList();
LayoutInflater inflater;
int id = 0;
public MyBaseAdapter(Context context, ArrayList items) {
this.context = context;
this.items = items;
inflater = LayoutInflater.from(this.context);
}
#Override
public int getCount() {
return items.size();
}
#Override
public ListData getItem(int position) {
return items.get(position);
}
#Override
public long getItemId(int position) {
return 0;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
MyViewHolder mViewHolder;
if (convertView == null) {
convertView = inflater.inflate(R.layout.list_item, parent, false);
mViewHolder = new MyViewHolder(convertView);
convertView.setTag(mViewHolder);
} else {
mViewHolder = (MyViewHolder) convertView.getTag();
}
ListData currentListData = getItem(position);
id = position > 0 ? getItem(position - 1).getID() : 0;
mViewHolder.Title.setText(currentListData.getTitle());
mViewHolder.Desc.setText(currentListData.getDescription());
if(1==1){
mViewHolder.Title.setVisibility(View.GONE);
}else {
if (id != currentListData.getID()) {
mViewHolder.Title.setVisibility(View.VISIBLE);
} else {
mViewHolder.Title.setVisibility(View.GONE);
}
}
return convertView;
}
private class MyViewHolder {
TextView Title, Desc;
public MyViewHolder(View item) {
Title = (TextView) item.findViewById(R.id.txtitem);
Desc = (TextView) item.findViewById(R.id.descitem);
Typeface title = Typeface.createFromAsset(context.getAssets(), "fonts/DroidSans.ttf");
Title.setTypeface(title);
Typeface desc = Typeface.createFromAsset(context.getAssets(), "fonts/DroidSans.ttf");
Desc.setTypeface(desc, Typeface.BOLD);
}
}
}

#Override
protected void onRestart() {
Intent intentBack = new Intent(getApplicationContext(),MainActivity.class);
startActivity(intentBack);
super.onRestart();
}

you did not have any callback after you back to this activity .
You can either override onResume() method or startActivityForResult and do something in the onAcitvityForResult method.

Cannot remove item from Shopping Cart android studio

I referred [this][1] and [this][2] site and tried to modify it according to my own needs. Problem is I can't remove an item from the cart. I have tried everything including searching for solutions in stackoverflow and google but no luck.
Here is my CatalogActivity.java
package com.comlu.sush.shoppingcart;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.ListView;
import android.widget.AdapterView.OnItemClickListener;
import java.util.List;
public class CatalogActivity extends AppCompatActivity {
private List<Product> mProductList;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_catalog);
// Obtain a reference to the product catalog
mProductList = ShoppingCartHelper.getCatalog(getResources());
// Create the list
ListView listViewCatalog = (ListView) findViewById(R.id.ListViewCatalog);
listViewCatalog.setAdapter(new ProductAdapter(mProductList, getLayoutInflater(), false,false));
listViewCatalog.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
Intent productDetailsIntent = new Intent(getBaseContext(),ProductDetailsActivity.class);
productDetailsIntent.putExtra(ShoppingCartHelper.PRODUCT_INDEX, position);
startActivity(productDetailsIntent);
}
});
Button viewShoppingCart = (Button) findViewById(R.id.ButtonViewCart);
viewShoppingCart.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent viewShoppingCartIntent = new Intent(getBaseContext(), ShoppingCartActivity.class);
startActivity(viewShoppingCartIntent);
}
});
}
}
ShoppingCartHelper.java
package com.comlu.sush.shoppingcart;
import android.content.res.Resources;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Vector;
public class ShoppingCartHelper {
public static final String PRODUCT_INDEX = "PRODUCT_INDEX";
private static List<Product> catalog;
private static Map<Product, ShoppingCartEntry> cartMap = new HashMap<Product, ShoppingCartEntry>();
public static List<Product> getCatalog(Resources res){
if(catalog == null) {
catalog = new Vector<Product>();
catalog.add(new Product("Dead or Alive", res
.getDrawable(R.drawable.first),
"Dead or Alive by Tom Clancy with Grant Blackwood", 29.99));
catalog.add(new Product("Switch", res
.getDrawable(R.drawable.second),
"Switch by Chip Heath and Dan Heath", 24.99));
catalog.add(new Product("Watchmen", res
.getDrawable(R.drawable.third),
"Watchmen by Alan Moore and Dave Gibbons", 14.99));
}
return catalog;
}
public static void setQuantity(Product product, int quantity) {
// Get the current cart entry
ShoppingCartEntry curEntry = cartMap.get(product);
// If the quantity is zero or less, remove the products
if(quantity <= 0) {
if(curEntry != null)
removeProduct(product);
return;
}
// If a current cart entry doesn't exist, create one
if(curEntry == null) {
curEntry = new ShoppingCartEntry(product, quantity);
cartMap.put(product, curEntry);
return;
}
// Update the quantity
curEntry.setQuantity(quantity);
}
public static int getProductQuantity(Product product) {
// Get the current cart entry
ShoppingCartEntry curEntry = cartMap.get(product);
if(curEntry != null)
return curEntry.getQuantity();
return 0;
}
public static void removeProduct(Product product) {
cartMap.remove(product);
}
public static List<Product> getCartList() {
List<Product> cartList = new Vector<Product>(cartMap.keySet().size());
for(Product p : cartMap.keySet()) {
cartList.add(p);
}
return cartList;
}
}
ShoppingCartActiity.java
package com.comlu.sush.shoppingcart;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.Button;
import android.widget.ListView;
import java.util.List;
public class ShoppingCartActivity extends AppCompatActivity {
private List<Product> mCartList;
private ProductAdapter mProductAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_shopping_cart);
mCartList = ShoppingCartHelper.getCartList();
// Make sure to clear the selections
for(int i=0; i<mCartList.size(); i++) {
mCartList.get(i).selected = false;
}
// Create the list
final ListView listViewCatalog = (ListView) findViewById(R.id.ListViewCatalog);
mProductAdapter = new ProductAdapter(mCartList, getLayoutInflater(), true,true);
listViewCatalog.setAdapter(mProductAdapter);
listViewCatalog.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
mProductAdapter.toggleSelection(position);
}
});
removeButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mProductAdapter.removeSelected();
}
});
}
#Override
protected void onResume() {
super.onResume();
// Refresh the data
if(mProductAdapter != null) {
mProductAdapter.notifyDataSetChanged();
}
}
}
ProductDetailsActivity.java
package com.comlu.sush.shoppingcart;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import java.util.List;
public class ProductDetailsActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_product_details);
final int result=0;
List<Product> catalog = ShoppingCartHelper.getCatalog(getResources());
int productIndex = getIntent().getExtras().getInt(
ShoppingCartHelper.PRODUCT_INDEX);
final Product selectedProduct = catalog.get(productIndex);
// Set the proper image and text
ImageView productImageView = (ImageView) findViewById(R.id.ImageViewProduct);
productImageView.setImageDrawable(selectedProduct.productImage);
TextView productTitleTextView = (TextView) findViewById(R.id.TextViewProductTitle);
productTitleTextView.setText(selectedProduct.title);
TextView productDetailsTextView = (TextView) findViewById(R.id.TextViewProductDetails);
productDetailsTextView.setText(selectedProduct.description);
// Update the current quantity in the cart
TextView textViewCurrentQuantity = (TextView) findViewById(R.id.textViewCurrentlyInCart);
textViewCurrentQuantity.setText("Currently in Cart: "
+ ShoppingCartHelper.getProductQuantity(selectedProduct));
// Save a reference to the quantity edit text
final EditText editTextQuantity = (EditText) findViewById(R.id.editTextQuantity);
Button addToCartButton = (Button) findViewById(R.id.ButtonAddToCart);
addToCartButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// Check to see that a valid quantity was entered
int quantity = 0;
try {
quantity = Integer.parseInt(editTextQuantity.getText()
.toString());
if (quantity < 0) {
Toast.makeText(getBaseContext(),
"Please enter a quantity of 0 or higher",
Toast.LENGTH_SHORT).show();
return;
}
} catch (Exception e) {
Toast.makeText(getBaseContext(),
"Please enter a numeric quantity",
Toast.LENGTH_SHORT).show();
return;
}
// If we make it here, a valid quantity was entered
ShoppingCartHelper.setQuantity(selectedProduct, quantity);
// Close the activity
finish();
}
});
}
}
ProductAdapter.java
package com.comlu.sush.shoppingcart;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.CheckBox;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.List;
public class ProductAdapter extends BaseAdapter {
private List<Product> mProductList;
private LayoutInflater mInflater;
private boolean mShowQuantity;
private boolean mShowCheckbox;
public ProductAdapter(List<Product> list, LayoutInflater inflater, boolean showQuantity, boolean showCheckbox) {
mProductList = list;
mInflater = inflater;
mShowQuantity = showQuantity;
mShowCheckbox = showCheckbox;
}
#Override
public int getCount() {
return mProductList.size();
}
#Override
public Object getItem(int position) {
return mProductList.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final ViewItem item;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.item, null);
item = new ViewItem();
item.productImageView = (ImageView) convertView
.findViewById(R.id.ImageViewItem);
item.productTitle = (TextView) convertView
.findViewById(R.id.TextViewItem);
item.productQuantity = (TextView) convertView
.findViewById(R.id.textViewQuantity);
item.productCheckbox = (CheckBox) convertView.findViewById(R.id.CheckBoxSelected);
convertView.setTag(item);
} else {
item = (ViewItem) convertView.getTag();
}
Product curProduct = mProductList.get(position);
item.productImageView.setImageDrawable(curProduct.productImage);
item.productTitle.setText(curProduct.title);
if(!mShowCheckbox) {
item.productCheckbox.setVisibility(View.GONE);
} else {
if(curProduct.selected == true)
item.productCheckbox.setChecked(true);
else
item.productCheckbox.setChecked(false);
}
// Show the quantity in the cart or not
if (mShowQuantity) {
item.productQuantity.setText("Quantity: "
+ ShoppingCartHelper.getProductQuantity(curProduct));
} else {
// Hid the view
item.productQuantity.setVisibility(View.GONE);
}
return convertView;
}
public void toggleSelection(int position) {
Product selectedProduct = (Product) getItem(position);
if(selectedProduct.selected) { // no need to check " == true"
selectedProduct.selected = false;
}
else {
selectedProduct.selected = true;
}
notifyDataSetInvalidated();
}
public void removeSelected() {
for(int i=mProductList.size()-1; i>=0; i--) {
if(mProductList.get(i).selected) {
mProductList.remove(i);
}
}
notifyDataSetChanged();
}
private class ViewItem {
ImageView productImageView;
TextView productTitle;
TextView productQuantity;
CheckBox productCheckbox;
}
}

You should move data manipulation to the adapter, and design-wise it would make sense and might also fix the problem you're telling us.
Write this method in your ProductAdapter:
public void removeSelected() {
for(int i = mProductList.size()-1; i >= 0; i--) {
if(mProductList.get(i).selected) {
mProductList.remove(i);
}
}
notifyDataSetChanged();
}
Update your OnClickListener (in your ShoppingCartActiity of course):
removeButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
mProductAdapter.removeSelected();
}
});
Edit
I noticed that you aren't applying OOP's concept of encapsulation here. That is, ShoppingCartActiity shouldn't be making changes to the data which belongs to your adapter.
So, just create public methods inside the ProductAdapter for item for selection, etc and call them from ShoppingCartActiity as needed.
Copy this method in your ProductAdapter:
public void toggleSelection(int position) {
Product selectedProduct = (Product) getItem(position);
if(selectedProduct.selected) { // no need to check " == true"
selectedProduct.selected = false;
}
else {
selectedProduct.selected = true;
}
notifyDataSetInvalidated();
}
mProductAdapter.toggleSelection(position); will replace following code ShoppingCartActiity:
Product selectedProduct = mCartList.get(position);
if(selectedProduct.selected == true)
selectedProduct.selected = false;
else
selectedProduct.selected = true;
mProductAdapter.notifyDataSetInvalidated();
Edit2
The problem is that the ShoppingCartActiity takes items from ShoppingCartEntry on starting up, but it never writes back the changes to it when you remove items.
update your removeButton's onClick() to:
mProductAdapter.removeSelected();
if (product.selected) {
// set products which are remaining in the adapter
ShoppingCartHelper.setProducts(mProductAdapter.getProducts());
}
ShoppingCartHelper.setProducts() would replace the old data with the passed one:
public static void setProducts(ArrayList<Product> products) {
catalog = new Vector<Product>();
for (Product product : products) {
catalog.add(product);
}
}
mProductAdapter.getProducts() will just return the list of Products, like:
public List<Product> getProducts() {
return mProductList;
}

you just have to remove selected item from list, and after adapter.notifiyDataSetChanged() it will refresh the adapter.
removeButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// Loop through and remove all the products that are selected
// Loop backwards so that the remove works correctly
for(int i=mCartList.size()-1; i>=0; i--) {
if(mCartList.get(i).selected) {
mCartList.remove(i);
//mProductAdapter.removeSelected();
}
}
if(mProductAdapter!=null)
mProductAdapter.notifyDataSetChanged();
}
});

Filter on listview disappear listitems while entering something into edittext

I am suffering a weird problem. Actually I have a customize listview in which I am using a filter, everything working fine but when I am typing a text to edittext it disappear the all listitem. I am strange why this going on with me, still I am not a champ of android so need some help. I have seen many similar problems on stackoverflow like this,this,this, and many more, but nothing works in my case. I dont know where i am doing mistake.
My listitem click working fine, So hope it will also work after item search into edittext.
Here is my MainActivity.java :
package com.sunil.listviewmuntilerowdelete;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.View;
import android.widget.AdapterView;
import android.widget.EditText;
import android.widget.ListView;
public class MainActivity extends Activity {
private String[] myfriendname = null;
EditText edtSearch;
private int[] photo = null;
ListView listView = null;
Context contex = null;
MyListAdapter adapter = null;
private List<MyFriendsSDetails> list = new ArrayList<MyFriendsSDetails>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
contex = this;
listView = (ListView) findViewById(R.id.listview);
edtSearch = (EditText) findViewById(R.id.EditText01);
myfriendname = new String[] { "Sunil Gupta", "Abhishek Tripathi",
"Sandeep Pal", "Amit Verma" };
photo = new int[] { R.drawable.sunil, R.drawable.abhi,
R.drawable.sandy, R.drawable.amit };
final String text[] = { "Sunil is a great man",
"Abhishek is hardworking", "Sandeep is same as amit",
"Amit is unique" };
final Integer[] image = { R.drawable.sunil, R.drawable.abhi,
R.drawable.sandy, R.drawable.amit,
};
for (int index = 0; index < myfriendname.length; index++) {
MyFriendsSDetails details = new MyFriendsSDetails(
myfriendname[index], photo[index]);
list.add(details);
}
adapter = new MyListAdapter(contex, list);
listView.setAdapter(adapter);
listView.setTextFilterEnabled(true);
edtSearch.addTextChangedListener(new TextWatcher() {
#Override
public void onTextChanged(CharSequence cs, int arg1, int arg2,
int arg3) {
// When user changed the Text
MainActivity.this.adapter.getFilter().filter(cs);
}
#Override
public void beforeTextChanged(CharSequence arg0, int arg1,
int arg2, int arg3) {
// TODO Auto-generated method stub
}
#Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
}
});
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
Intent intent = new Intent(MainActivity.this,
SecondActivity.class);
intent.putExtra("key1", image[position]);
intent.putExtra("key2", text[position]);
startActivity(intent);
}
});
}
}
MyListAdapter.java
package com.sunil.listviewmuntilerowdelete;
import java.util.List;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class MyListAdapter extends ArrayAdapter<MyFriendsSDetails> {
Context context;
LayoutInflater inflater;
List<MyFriendsSDetails> list;
public MyListAdapter(Context context, List<MyFriendsSDetails> list) {
super(context, 0, list);
this.context = context;
this.list = list;
inflater = LayoutInflater.from(context);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder holder;
if (convertView == null) {
holder = new ViewHolder();
convertView = inflater.inflate(R.layout.list_item, null);
holder.name = (TextView) convertView.findViewById(R.id.title);
holder.photo = (ImageView) convertView.findViewById(R.id.icon);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.name.setText(list.get(position).getMyfriendname());
holder.photo.setImageResource(list.get(position).getPhoto());
return convertView;
}
private class ViewHolder {
TextView name;
ImageView photo;
}
}
Here is MyFriendsSDetails.java :
package com.sunil.listviewmuntilerowdelete;
public class MyFriendsSDetails {
private String myfriendname = null;
private int photo = 0;
public MyFriendsSDetails(String friendname, int myphoto) {
this.myfriendname = friendname;
this.photo = myphoto;
}
public String getMyfriendname() {
return myfriendname;
}
public void setMyfriendname(String myfriendname) {
this.myfriendname = myfriendname;
}
public int getPhoto() {
return photo;
}
public void setPhoto(int photo) {
this.photo = photo;
}
}
Thanks in advance.

As you are using custom adapter, android cant recognize "MainActivity.this.adapter.getFilter().filter(cs);"
You have to override getFilter() method and do manual changes.
Checkout below code :
#Override
public Filter getFilter() {
Filter filter = new Filter() {
#SuppressWarnings("unchecked")
#Override
protected void publishResults(CharSequence constraint,FilterResults results) {
mDisplayedValues = (ArrayList<HashMap<String, String>>) results.values; // has the filtered values
notifyDataSetChanged(); // notifies the data with new filtered values
}
#Override
protected FilterResults performFiltering(CharSequence constraint) {
FilterResults results = new FilterResults(); // Holds the results of a filtering operation in values
ArrayList<HashMap<String, String>> FilteredArrList = new ArrayList<HashMap<String, String>>();
if (mOriginalValues == null) {
mOriginalValues = new ArrayList<HashMap<String, String>>(mDisplayedValues); // saves the original data in mOriginalValues
}
/********
*
* If constraint(CharSequence that is received) is null returns the mOriginalValues(Original) values
* else does the Filtering and returns FilteredArrList(Filtered)
*
********/
if (constraint == null || constraint.length() == 0) {
// set the Original result to return
results.count = mOriginalValues.size();
results.values = mOriginalValues;
} else {
constraint = constraint.toString().toLowerCase();
for (int i = 0; i < mOriginalValues.size(); i++) {
String data = mOriginalValues.get(i).get("name");
if (data.toLowerCase().startsWith(constraint.toString())) {
HashMap<String, String> hmap=new HashMap<String, String>();
hmap.put("name", mOriginalValues.get(i).get("name"));
hmap.put("image", mOriginalValues.get(i).get("image"));
FilteredArrList.add(hmap);
Log.e("DEBUG", "name : "+data);
}
}
// set the Filtered result to return
results.count = FilteredArrList.size();
results.values = FilteredArrList;
}
return results;
}
};
return filter;
}
and use it in your adapter getView()
holder.name.setText(mDisplayedValues.get(position).get("name"));

Custom listview implementation using checkboxes and buttons. Android

I have implemented a custom adapter class for controlling my listview. I'm implementing a button, a textbox and a checkbox against each row in the listview. I have a couple of buttons that are not part of the listview. They are below the listview. Now when I check any number of boxes and press the button that is not part of the listview, I want to be able to delete the checked boxes (if there are any). In other words, I want to b able to delete the checked items with the click of a button that is not part of the listview.
Here's my main class...
public class ASvideofiles extends Activity implements OnClickListener {
int count = 0;
private String[] vidNames;
private String[] vidPaths;
private ListView myList;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.asvideofiles);
Button b1 = (Button) findViewById(R.id.button1);
b1.setOnClickListener(this);
Button b2 = (Button) findViewById(R.id.button2);
b2.setOnClickListener(this);
File f = new File(Environment.getExternalStorageDirectory(),
"ABC/XYZ/");
File[] files = f.listFiles();
vidNames = new String[files.length];
vidPaths = new String[files.length];
if(files != null) {
for(int i=0; i < files.length; i++) {
vidNames[i] = files[i].getName();
vidPaths[i] = files[i].getPath();
count ++;
}
}
ArrayList<String> list = new ArrayList<String>();
for (int i = 0; i < files.length; i++) {
list.add(vidNames[i]);
}
myList = (ListView)findViewById(R.id.listView1);
myList.setAdapter(new AScustomadapter(ASvideofiles.this, list));
}
#Override
public void onClick(View v) {
if(v.getId() == R.id.button1) {
} else if(v.getId() == R.id.button2) {
}
}
}
Here's my Adapter class...
public class AScustomadapter extends BaseAdapter {
private ArrayList<String> mListItems;
private LayoutInflater mLayoutInflater;
int i = 0;
private ArrayList<Integer> checkedIndices = new ArrayList<Integer>();
public AScustomadapter(Context context, ArrayList<String> arrayList) {
mListItems = arrayList;
//get the layout inflater
mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
#Override
public int getCount() {
return mListItems.size();
}
#Override
public Object getItem(int i) {
return null;
}
#Override
public long getItemId(int i) {
return 0;
}
public int getTotalCheckedCount() {
return checkedIndices.size();
}
#Override
public View getView(final int position, View view, ViewGroup viewGroup) {
ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = mLayoutInflater.inflate(R.layout.list_item, null);
holder.itemName = (TextView) view.findViewById(R.id.list_item_text_view);
holder.cb1 = (CheckBox) view.findViewById(R.id.checkBox1);
view.setTag(holder);
} else {
holder = (ViewHolder)view.getTag();
}
final String stringItem = mListItems.get(position);
if (stringItem != null) {
if (holder.itemName != null) {
holder.itemName.setText(stringItem);
}
}
holder.cb1.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
if(checkedIndices.contains(position)){
}else {
checkedIndices.add(position);
}
}else {
checkedIndices.remove((Integer)position);
}
}
});
if(checkedIndices.contains((Integer)position)) {
holder.cb1.setChecked(true);
} else {
holder.cb1.setChecked(false);
}
//this method must return the view corresponding to the data at the specified position.
return view;
}
private static class ViewHolder {
protected TextView itemName;
protected CheckBox cb1;
}
}
The rows are basically populated with videos, so all in all, I want to be able to delete the selected videos against which the check boxes are checked and the delete button is pressed. Help required. Thanks in advance.

Maintain a Boolean Array which keeps track of the position of the rows of checked CheckBoxes.
Then in your Button onClickListener remove those items from the ArrayList and pass this updated ArrayList to your adapter.
Finally call notifyDataSetChanged()

Here , i have a solution for you. I have added your adapter class in the main activity itself. Basically i have created two array list of type string. When you check a checkbox, the corresponding textview value is stored in it the list CHECKEDLIST. In the other list ALLVALUES, all the values are stored.
On button click i match both the lists and if a match occurs, then i remove that value from ALLVALUES and call notifydatasetchanged
package com.example.test;
import java.io.File;
import java.util.ArrayList;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.os.Environment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.View.OnClickListener;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.CompoundButton.OnCheckedChangeListener;
public class MainActivity extends Activity implements OnClickListener {
private ArrayList<String> checkedIndices = new ArrayList<String>();
ArrayList<String> list = new ArrayList<String>();
AScustomadapter adapter;
int count = 0;
private String[] vidNames = {"a","b","c","d","e","f","g","h","i"};
private ListView myList;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button b1 = (Button) findViewById(R.id.button1);
b1.setOnClickListener(this);
for (int i = 0; i < vidNames.length; i++) {
list.add(vidNames[i]);
}
myList = (ListView)findViewById(R.id.list);
adapter = new AScustomadapter(getApplicationContext(), list);
myList.setAdapter(adapter);
}
#Override
public void onClick(View v) {
if(v.getId() == R.id.button1) {
for (int i = 0; i < checkedIndices.size(); i++) {
for(int j = 0; j <list.size();j++){
if(list.get(j).contains(checkedIndices.get(i))){
list.remove(j);
}
}
}
adapter.notifyDataSetChanged();
}
}
public class AScustomadapter extends BaseAdapter {
private ArrayList<String> mListItems;
private LayoutInflater mLayoutInflater;
int i = 0;
public AScustomadapter(Context context, ArrayList<String> arrayList) {
mListItems = arrayList;
//get the layout inflater
mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
#Override
public int getCount() {
return mListItems.size();
}
#Override
public Object getItem(int i) {
return list.get(i);
}
#Override
public long getItemId(int i) {
return 0;
}
public int getTotalCheckedCount() {
return checkedIndices.size();
}
#Override
public View getView(final int position, View view, ViewGroup viewGroup) {
ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = mLayoutInflater.inflate(R.layout.list_item, null);
holder.itemName = (TextView) view.findViewById(R.id.list_item_text_view);
holder.cb1 = (CheckBox) view.findViewById(R.id.checkBox1);
view.setTag(holder);
} else {
holder = (ViewHolder)view.getTag();
}
final String stringItem = mListItems.get(position);
if (stringItem != null) {
if (holder.itemName != null) {
holder.itemName.setText(stringItem);
}
}
holder.cb1.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
//is chkIos checked?
if (((CheckBox) v).isChecked()) {
if(!checkedIndices.contains(getItem(index).toString()))
checkedIndices.add(getItem(index).toString()); }
else {
checkedIndices.remove(getItem(index).toString());
}
//case 2
}
});
if(checkedIndices.contains((Integer)position)) {
holder.cb1.setChecked(true);
} else {
holder.cb1.setChecked(false);
}
//this method must return the view corresponding to the data at the specified position.
return view;
}
private class ViewHolder {
protected TextView itemName;
protected CheckBox cb1;
}
}
}