I am working on a shopping cart app,Items are displayed as below.There is a plus, minus (+/-) buttons to choose the number of quantity.
If product quantity is changed, I need to pass "productname" and "quantity" to the main activity so that I could use them to prepare final cart. I got some suggestions to use database or some content providers,
I am not sure how to do it.., please help
MainActivity.java
public class MainActivity extends AppCompatActivity {
RecyclerView recyclerView;
RecycleAdapter recycleAdapter;
List<HashMap<String, String>> onlineData;
ProgressDialog pd;
Toolbar toolbar;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = (RecyclerView) findViewById(R.id.recyle_view);
toolbar= (Toolbar) findViewById(R.id.anim_toolbar);
setSupportActionBar(toolbar);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getBaseContext());
recyclerView.setLayoutManager(linearLayoutManager);
recyclerView.setHasFixedSize(true);
final String url = "http://www.qa4.org/?json=get_recent_posts&count=45";
new AsyncHttpTask().execute(url);
}
public class AsyncHttpTask extends AsyncTask<String, Void, Integer> {
#Override
protected void onPreExecute() {
pd=new ProgressDialog(MainActivity.this);
pd.requestWindowFeature(Window.FEATURE_NO_TITLE);
pd.setMessage("Loading please wait...");
pd.setCancelable(false);
pd.show();
}
#Override
protected Integer doInBackground(String... params) {
Integer result = 0;
HttpURLConnection urlConnection;
try {
URL url = new URL(params[0]);
urlConnection = (HttpURLConnection) url.openConnection();
int statusCode = urlConnection.getResponseCode();
// 200 represents HTTP OK
if (statusCode == 200) {
BufferedReader r = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
StringBuilder response = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
response.append(line);
}
parseResult(response.toString());
result = 1; // Successful
} else {
result = 0; //"Failed to fetch data!";
}
} catch (Exception e) {
e.printStackTrace();
}
return result; //"Failed to fetch data!";
}
#Override
protected void onPostExecute(Integer result) {
// Download complete. Let us update UI
pd.dismiss();
if (result == 1) {
recycleAdapter = new RecycleAdapter(MainActivity.this,onlineData);
recyclerView.setAdapter(recycleAdapter);
} else {
Toast.makeText(MainActivity.this, "Failed to fetch data!", Toast.LENGTH_SHORT).show();
}
}
}
private void parseResult(String result) {
try {
JSONObject response = new JSONObject(result);
JSONArray posts = response.optJSONArray("posts");
onlineData = new ArrayList<>();
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.optJSONObject(i);
HashMap<String, String> item = new HashMap<>();
item.put("title", post.optString("title"));
JSONArray jsonArray = post.getJSONArray("attachments");
JSONObject jsonObject1 = jsonArray.getJSONObject(0);
JSONObject jsonArrayImages = jsonObject1.getJSONObject("images");
JSONObject jsonArrayThumb = jsonArrayImages.getJSONObject("thumbnail");
item.put("thump", jsonArrayThumb.optString("url"));
onlineData.add(item);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
RecycleAdapter.java
public class RecycleAdapter extends RecyclerView.Adapter<RecycleAdapter.ViewHolderRec> {
List<HashMap<String, String>> onlineData;
SQLiteDatabase db;
Context context;
RecycleAdapter(Context context,List<HashMap<String, String>> onlineData){
this.onlineData = onlineData;
this.context=context;
}
#Override
public ViewHolderRec onCreateViewHolder(ViewGroup parent, int viewType) {
return new ViewHolderRec( LayoutInflater.from(parent.getContext()).inflate(R.layout.item_recycle, parent, false));
}
#Override
public void onBindViewHolder(ViewHolderRec holder, int position) {
HashMap<String,String> map =onlineData.get(position);
//Download image using picasso library
Picasso.with(context).load(map.get("thump"))
.error(R.drawable.placeholder)
.placeholder(R.drawable.placeholder)
.into(holder.iv);
holder.tv.setText(map.get("title"));
}
#Override
public int getItemCount() {
return onlineData.size();
}
public class ViewHolderRec extends RecyclerView.ViewHolder implements View.OnClickListener{
ImageView iv;
TextView tv, quantity;
ImageView Add_Cart;
ImageView Remove_Cart;
public ViewHolderRec(View itemView) {
super(itemView);
iv = (ImageView) itemView.findViewById(R.id.thumbnail);
tv = (TextView) itemView.findViewById(R.id.title);
quantity = (TextView)itemView.findViewById(R.id.cart_qty);
Add_Cart = (ImageView)itemView.findViewById(R.id.cart_add);
Remove_Cart = (ImageView)itemView.findViewById(R.id.cart_remove);
itemView.setOnClickListener(this);
Add_Cart.setOnClickListener(this);
Remove_Cart.setOnClickListener(this);
}
#Override
public void onClick(View v) {
if(v.getId() == Add_Cart.getId()){
increment();
}
else if(v.getId() == Remove_Cart.getId()){
decrement();
}
}
public void increment(){
int currentNos = Integer.parseInt(quantity.getText().toString()) ;
quantity.setText(String.valueOf(++currentNos));
}
public void decrement(){
int currentNos = Integer.parseInt(quantity.getText().toString()) ;
quantity.setText(String.valueOf(--currentNos));
}
}
}
How to do this,
You should create interface, and activity implements this interface.
public interface OnItemClick {
void onClick (String value);
}
When you create adapter (last parameter is this interface)
public class MainActivity extends AppCompatActivity implements OnItemClick {
recycleAdapter = new RecycleAdapter(MainActivity.this,onlineData, this);
recyclerView.setAdapter(recycleAdapter);
#Override
void onClick (String value){
// value this data you receive when increment() / decrement() called
}
// In Adapter
private OnItemClick mCallback;
RecycleAdapter(Context context,List<HashMap<String, String>> onlineData,OnItemClick listener){
this.onlineData = onlineData;
this.context = context;
this.mCallback = listener;
}
....
public void increment(){
int currentNos = Integer.parseInt(quantity.getText().toString()) ;
quantity.setText(String.valueOf(++currentNos));
mCallback.onClick(quantity.getText().toString());
}
public void decrement(){
int currentNos = Integer.parseInt(quantity.getText().toString()) ;
quantity.setText(String.valueOf(--currentNos));
mCallback.onClick(quantity.getText().toString());
}
I failed to do it with both Interface and Observer pattern. But Local Broadcast worked for me.
In Adapter
String ItemName = tv.getText().toString();
String qty = quantity.getText().toString();
Intent intent = new Intent("custom-message");
// intent.putExtra("quantity",Integer.parseInt(quantity.getText().toString()));
intent.putExtra("quantity",qty);
intent.putExtra("item",ItemName);
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
Main Activity
public void onCreate(Bundle savedInstanceState) {
...
// Register to receive messages.
// We are registering an observer (mMessageReceiver) to receive Intents
// with actions named "custom-message".
LocalBroadcastManager.getInstance(this).registerReceiver(mMessageReceiver,
new IntentFilter("custom-message"));
}
...
public BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// Get extra data included in the Intent
String ItemName = intent.getStringExtra("item");
String qty = intent.getStringExtra("quantity");
Toast.makeText(MainActivity.this,ItemName +" "+qty ,Toast.LENGTH_SHORT).show();
}
};
Three popular ways to solve this problem
Interfaces
Phuoc Huynh has already explained how to use interfaces to solves this.
Observer pattern.
Try googling around observer to understand how it works. We will register the classes who want to receive events with the type of events they want to receive. There will be a manager classes to manage registering and unregistering of receivers and also to send the events to all receivers
public class EventManager {
private static EventManager eventManager;
private static Object syncObject = new Object();
private HashMap<String, ArrayList<EventListener>> listeners = new HashMap<>();
private EventManager(){}
public static EventManager getInstance() {
if (eventManager == null) {
synchronized (syncObject) {
if (eventManager == null) {
eventManager = new EventManager();
}
}
}
return eventManager;
}
public synchronized void registerListener(String event, EventListener listener) {
if (listeners.containsKey(event)) {
listeners.get(event).add(listener);
} else {
ArrayList<EventListener> arrayList = new ArrayList<>();
arrayList.add(listener);
listeners.put(event, arrayList);
}
}
public synchronized void unRegisterListener(String event, EventListener listener) {
if (listeners.containsKey(event)) {
listeners.get(event).remove(listener);
if (listeners.get(event).size() == 0) {
listeners.remove(event);
}
}
}
public void sendEvent(String event, Object o) {
if (listeners.containsKey(event)) {
ArrayList<EventListener> listener = listeners.get(event);
for (EventListener eventListener : listener) {
eventListener.onEvent(o);
}
}
}
}
Your MainActivity will register itself as a receiver of increment and decrement events and also implement onEvent method of IEventListener
public class MainActivity extends AppCompatActivity implements IEventListener{
#Override
protected void onCreate(Bundle onSavedInstanceState) {
EventManager.getInstance().registerEvent("increment", this);
EventManager.getInstance().registerEvent("decrement", this)
}
#Override
public void onEvent(String event) {
if (event.equals("increment") {
//increment
} else if (event.equals("decrement") {
//decrement
}
}
#Override
protected void onDestroy() {
EventManager.getInstance().unRegisterEvent("increment", this);
EventManager.getInstance().unRegisterEvent("decrement", this)
}
}
In you adapter class send the events
EventManager.getInstance().sendEvent("increment");
EventManager.getInstance().sendEvent("decrement");
LocalBroadcasts
LocalBroadcasts works the same way as the above example. you have get Instance of LocalBroadcastManger and send Broadcast on it. Define a broadcast receiver in the onCreate of the activity and register it using registerReceiver() in the Activity. Pass an intent filter in the register receiver with actiontype same as the broadcasts you want your activity to receive. Make sure you unregister the broadcasts whenever you don't need them or in the onDestroy of the activity
Simple solution using interface:
Create an interface with method containing objects/data as parameters:
public interface RecyclerViewDataPass {
public void pass(String productName, String quantity);
}
Implement interface method in Activity & pass it through RecyclerView Adapter:
RecyclerViewDataPass recyclerViewDataPass = new RecyclerViewDataPass() {
#Override
public void pass(String productName, String quantity) {
//we get data from adapter here
//assign parameters to activity variables or do the needed operations
}
};
recycleAdapter = new RecycleAdapter(MainActivity.this,onlineData,recyclerViewDataPass);
recyclerView.setAdapter(recycleAdapter);
Edit adapter's constructor:
public class RecycleAdapter extends RecyclerView.Adapter<RecycleAdapter.ViewHolderRec> {
List<HashMap<String, String>> onlineData;
SQLiteDatabase db;
Context context;
RecyclerViewDataPass recyclerViewDataPass; //here is our data pass object
RecycleAdapter(Context context,List<HashMap<String, String>> onlineData, RecyclerViewDataPass recyclerViewDataPass){
this.onlineData = onlineData;
this.context=context;
this.recyclerViewDataPass=recyclerViewDataPass; //get data pass object from activity
}
Inside RecyclerView Adapter call pass function to send data to activity:
recyclerViewDataPass.pass(tv.getText().toString(), quantity.getText().toString());
Check out this. It works for me.
Just Paste in Your Activity or Fragment
rvSelectedProductList = Recyclerview
selcetedItemAdapter = RecyclerView Adapter
rvSelectedProductList.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
final int itemCount = selectedItemAdapter.getItemCount();
for (int i = 0; i < itemCount; i++) {
TextView tvSelling = rvSelectedProductList.getChildAt(i).findViewById(R.id.tvSelling);
TextView textViewDrawerTitle = rvSelectedProductList.getChildAt(i).findViewById(R.id.tvCartQty);
String totalamount = tvSelling.getText().toString();
String qty = textViewDrawerTitle.getText().toString();
System.out.println("qty" + qty);
System.out.println("total" + totalamount);
}
rvSelectedProductList.getViewTreeObserver().removeGlobalOnLayoutListener(this);
}
});
//Simply it works for me
//In onBindViewHolder of RecyclerAdapter write the following code on clickEvent of any view;
Intent intent = new Intent(tContext, TargetActivity.class);
intent.putExtra("key", "value");
tContext.startActivity(intent);
//TargetActivity.java
String str = getIntent().getStringExtra("key");
//You got the value as String :)
add these codes in onBindViewHolder
Intent intent = new Intent("message_subject_intent");
intent.putExtra("name" , String.valueOf(messageSubject.getname()));
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
Add on MainActivity
public BroadcastReceiver mMessageReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String name= intent.getStringExtra("name");
Toast.makeText(MainActivity.this, name, Toast.LENGTH_SHORT).show();
}
};
LocalBroadcastManager.getInstance(this).registerReceiver(mMessageReceiver,new IntentFilter("message_subject_intent"));
Related
I'm creating a chat feature for an application and it works super fine. But I would like to show the user that message has been sent or it still wating for the server's response.
Fields:
List<ChatMessage> chatMessages;
ChatAdapter chatAdapter;
RecyclerView chatRecyclerView;
ImageButton submitMessageBtn;
this how I send a message on my ChatActivity class:
public void submitMessage(final String messageType, final byte[] message){
final ChatMessageResponse messageObject = new ChatMessageResponse();
new AsyncTask<Void, Void, Void>() {
#Override
protected void onPreExecute() {
super.onPreExecute();
messageObject.setMessage( message);
messageObject.setYours(true);
messageObject.setUserNickname(getNickname());
messageObject.setCreationDate(DateTime.now().withZone(DateTimeZone.UTC));
messageObject.setType(messageType);
AddMessage(messageObject);
}
#Override
protected Void doInBackground(Void... voids) {
try {
chatClient.chat().sendMessage(eventId, messageType, message);
runOnUiThread(new Runnable() {
#Override
public void run() {
// Update message on the list after has been sent to server
}
});
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}.execute();
}
public void AddMessage(ChatMessage message)
{
chatMessages.add(message);
chatAdapter.notifyDataSetChanged();
chatRecyclerView.scrollToPosition(chatMessages.size() -1);
}
When message is immediatly added to the adapter it should look like this:
my ChatAdapter class is setup like this:
public class ChatAdapter extends RecyclerView.Adapter<ChatAdapter.ChatViewHolder> {
private static final int VIEW_TYPE_MESSAGE_THIS_USER = 0;
private static final int VIEW_TYPE_MESSAGE_OTHER_USER = 1;
private final Activity activity;
public List<ChatMessage> chats=new ArrayList<>();
ArrayList<String> usercolor=new ArrayList<>();
Context mContext;
View view;
public ChatAdapter(List<ChatMessage> chats, Context mContext, Activity activity) {
this.chats = chats;
this.mContext = mContext;
this.activity = activity;
}
#Override
public ChatViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
mContext = parent.getContext();
if (viewType == VIEW_TYPE_MESSAGE_OTHER_USER) {
view = View.inflate(mContext, R.layout.message_item_left, null);
} else if (viewType == VIEW_TYPE_MESSAGE_THIS_USER){
view = View.inflate(mContext, R.layout.message_item, null);
}
return new ChatViewHolder(view,(View.OnLongClickListener)activity);
}
#Override
public void onBindViewHolder(final ChatViewHolder holder, int position){
final ChatMessageResponse m = (ChatMessageResponse) chats.get(position);
if (getItemViewType(position) == VIEW_TYPE_MESSAGE_OTHER_USER){
holder.bindToView1(m);
} else if (getItemViewType(position) == VIEW_TYPE_MESSAGE_THIS_USER)
{
holder.bindToView(m);
}
}
#Override
public int getItemCount() {
return chats.size();
}
#Override
public int getItemViewType(int position) {
return chats.get(position).isYours() ? VIEW_TYPE_MESSAGE_THIS_USER : VIEW_TYPE_MESSAGE_OTHER_USER;
}
}
When the server's response is positive the views in the ChatViewHolder (that I don't show the code because is too long) should change visibility state
Someone told me to get a referece for the view and change it on the activity's asynctask or create a Callback listener for my adapter.
But I have no Idea how to do either one of then any help is appreciated.
Are you familiar with the use of "Callbacks" or "Interfaces"? You can create an interface and implement it in your activity. Pass the callback by parameters in the "AsyncTask" and use it there.
//Interface class
/**
* Created by gmora
*/
public interface IProcess {
void updateAdapter(String result);
}
On Activity:
public class YourActivity extends AppCompatActivity {
private IProcess mProcess;
private Adapter mRecyclerAdapter;
private RecyclerView mRecyclerView;
private List<ChatMessage> chats; //update chats on activity and refresh your adapter
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_layout);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mProcess = new IProceso() {
#Override
public void updateAdapter(String pException) {
//update chats ... and update mAdater.notifyDataChange()...
// or mRecyclerView.setAdapter(new Adpater.... with new list chats)..
}
};
mRecyclerView = find....
// etc....
mRecyclerAdapter = new RecyclerAdapter( chats, ...);
mRecyclerView.setAdapter(mRecyclerAdapter);
}
}
Finally on AsyncTask... create a external class from AsyncTask please!
/**
* Created by gmora.
*/
public class YourAsyncTaskClass extends AsyncTask<String, Void, String > {
private IProcess iProcess;
public StarSearchPrinterTask(IProcess pIProcess) {
this.iProcess= pIProcess;
}
#Override
protected void onPreExecute() {
//loading... its optional
}
#Override
protected String doInBackground(String... interfaceType) {
// execute webservice or api and get results..
return results;
}
#Override
protected void onPostExecute(String results) {
mIProceso.updateAdapter(results);
}
}
This is my Activity:
public class HomeTimelineActivity extends AppCompatActivity {
private TwitterClient client;
Context mContext;
#BindView(R.id.rvTweets)
RecyclerView rvTweets;
List<Tweet> mTweets;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home_timeline);
Butterknife.bind(this);
client = TwitterApplication.getRestClient();
populateTimeline();
}
private void populateTimeline() {
client.getHomeTimeline(new JsonHttpResponseHandler() {
#Override
public void onSuccess(int statusCode, Header[] headers, JSONArray jsonArray) {
Log.d("DEBUG", jsonArray.toString());
mTweets = new ArrayList<Tweet>();
for (int i = 0; i < jsonArray.length(); i++) {
try {
JSONObject jsonTweet = jsonArray.getJSONObject(i);
Tweet tweet = new Tweet();
tweet.setBody(jsonTweet.getString("text"));
tweet.setUid(jsonTweet.getLong("id"));
tweet.setCreateAt(jsonTweet.getString("created_at"));
JSONObject jsonUser = jsonTweet.getJSONObject("user");
User user = new User();
user.setName(jsonUser.getString("name"));
user.setUid(jsonUser.getLong("id"));
user.setScreenname(jsonUser.getString("screen_name"));
user.setProfileImageurl(jsonUser.getString("profile_image_url"));
tweet.setUser(user);
mTweets.add(tweet);
runOnUiThread(new Runnable() {
#Override
public void run() {
TweetAdapter adapter = new TweetAdapter(mContext, mTweets);
rvTweets.setAdapter(adapter);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(mContext);
rvTweets.setLayoutManager(layoutManager);
}
});
} catch (JSONException e) {
e.printStackTrace();
continue;
}
}
}
#Override
public void onFailure(int statusCode, Header[] headers, Throwable throwable, JSONArray errorResponse) {
Log.d("DEBUT", errorResponse.toString());
}
});
}
}
This is my Adapter:
public class TweetAdapter extends RecyclerView.Adapter<TweetAdapter.TweetViewHolder>{
private Context mContext;
private List<Tweet> mTweets;
// Automatically add the Constructor here
public TweetAdapter(Context context, List<Tweet> tweets) {
mContext = context;
mTweets = tweets;
}
// Implements compulsory methods
#Override
public TweetViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.tweet_list_items,
parent, false);
TweetViewHolder viewHolder = new TweetViewHolder(view);
return viewHolder;
}
#Override
public void onBindViewHolder(TweetViewHolder holder, int position) {
holder.bindModel(mTweets.get(position));
}
#Override
public int getItemCount() {
return mTweets.size();
}
public class TweetViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
// Hook the ID to new created Widget using ButterKnife
#BindView(R.id.imgUserProfile)
ImageView userProfile;
#BindView(R.id.tvUserName)
TextView userName;
#BindView(R.id.tvTweet)
TextView tweetText;
TweetViewHolder(View view) {
super(view);
ButterKnife.bind(this, view);
// Set the OnclickListener of an item in list
itemView.setOnClickListener(this);
}
void bindModel(Tweet tweet) {
// Use the Widget mVar and the model name to set_get info
tweetText.setText(tweet.getBody());
}
#Override
public void onClick(View view) {
// Add What happen with OnClick
}
}
}
I try to set the Adapter with the mTweets List. I used debugger to make sure that the getTweet method has returned enough Object
tweets = {ArrayList#5524} size = 25
0 = {Tweet#5530}
1 = {Tweet#5531}
2 = {Tweet#5532}
3 = {Tweet#5533}
4 = {Tweet#5534}
5 = {Tweet#5535}
6 = {Tweet#5536}
7 = {Tweet#5537}
8 = {Tweet#5538}
9 = {Tweet#5539}
10 = {Tweet#5540}
11 = {Tweet#5541}
However, when I try to set the Adapter, there is no data displayed and the app immediately stopped. Strange, the Logcat is blank without any information. It's simply black. The authentication with Twitter worked.
Anyone please help me with this.
There are some steps you need to follow to improve your code performance and get it up and running.
The main thing which you are missing is that you are setting the mTweets after every iteration in the loop. You should set mTweets in the Adapter only after the entire list is populated. Following that, you should call adapter notifyDataSetChanged().
Follow these:
step 1
// Class variable adapter...
private TweetAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home_timeline);
client = TwitterApplication.getRestClient();
// Initially pass null as the mTweets since you don't have any tweets right now...
adapter = new TweetAdapter(mContext, null);
rvTweets.setAdapter(adapter);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(mContext);
rvTweets.setLayoutManager(layoutManager);
populateTimeline();
}
step 2
In your TweetAdapter, modify getItemCount method to handle the null checks on mTweets. Add a new Method addNewTweets to your Adapter.
#Override
public int getItemCount() {
return (mTweets !=null) ? mTweets.size() : 0;
}
public void setNewTweets(List<Tweet> newTweetList) {
this.mTweets = newTweetList;
}
step 3
Modify this method populateTimeline
private void populateTimeline() {
client.getHomeTimeline(new JsonHttpResponseHandler() {
#Override
public void onSuccess(int statusCode, Header[] headers, JSONArray jsonArray) {
Log.d("DEBUG", jsonArray.toString());
mTweets = new ArrayList<Tweet>();
for (int i = 0; i < jsonArray.length(); i++) {
try {
JSONObject jsonTweet = jsonArray.getJSONObject(i);
Tweet tweet = new Tweet();
tweet.setBody(jsonTweet.getString("text"));
tweet.setUid(jsonTweet.getLong("id"));
tweet.setCreateAt(jsonTweet.getString("created_at"));
JSONObject jsonUser = jsonTweet.getJSONObject("user");
User user = new User();
user.setName(jsonUser.getString("name"));
user.setUid(jsonUser.getLong("id"));
user.setScreenname(jsonUser.getString("screen_name"));
user.setProfileImageurl(jsonUser.getString("profile_image_url"));
tweet.setUser(user);
mTweets.add(tweet);
/* REMOVE THIS CODE!
runOnUiThread(new Runnable() {
#Override
public void run() {
TweetAdapter adapter = new TweetAdapter(mContext, mTweets);
rvTweets.setAdapter(adapter);
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(mContext);
rvTweets.setLayoutManager(layoutManager);
}
});
*/
} catch (JSONException e) {
e.printStackTrace();
continue;
}
// NOW SET MTWEETS IN YOUR ADAPTER.
// NOTIFY the adapter that the data is changed.
adapter.setNewTweets(mTweets);
adapter.notifyDataSetChanged();
}
}
hope you fine and well,
i have the following main class :
public class MainActivity extends AppCompatActivity {
Activity activity;
ViewPager viewPager;
CustomAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewPager=(ViewPager)findViewById(R.id.view_pager);
adapter=new CustomAdapter(this);
viewPager.setAdapter(adapter);
ConnectionAsyncTask connectionAsyncTask = new
ConnectionAsyncTask(MainActivity.this);
connectionAsyncTask.execute("http://www.mocky.io/v2/570d3677270000f600dc29b6");
}
public void showUploader()
{
// findViewById(R.id.progressBar1).setVisibility(View.VISIBLE);
}
public void hideUploader()
{
//findViewById(R.id.progressBar1).setVisibility(View.GONE);
}
public void DisplyOnTextView(List< Student > students) {
List <Student> my = students ;
}
}
when i run the app, this main activity will use another class to read json data from link as follows:
public class StudentJasonParser {
public static List<Student> getObjectFromJason(String jason)
{
List<Student> students;
try {
JSONArray jsonArray = new JSONArray(jason);
students = new ArrayList<>();
for(int i=0;i<jsonArray.length();i++)
{
JSONObject jsonObject = new JSONObject();
jsonObject= (JSONObject) jsonArray.get(i);
Student student = new Student();
student.setID(jsonObject.getInt("id"));
student.setName(jsonObject.getString("name"));
student.setUrl(jsonObject.getString("url"));
student.setDes(jsonObject.getString("des\n"));
student.setRate(jsonObject.getDouble("rate"));
student.setLon(jsonObject.getDouble("lon"));
student.setLat(jsonObject.getDouble("lat"));
students.add(student);
}
} catch (JSONException e) {
e.printStackTrace();
return null;
}
return students;
}
}
now this class will return the data to the following class :
public class ConnectionAsyncTask extends AsyncTask<String,String,String> {
Activity activity;
public ConnectionAsyncTask(Activity activity) {
this.activity=activity;
}
#Override
protected void onPreExecute() {
//((MainActivity)activity).DisplyOnTextView();
((MainActivity)activity).showUploader();
}
#Override
protected String doInBackground(String... params) {
String content =HttpManager.getData(params[0]);
return content;
}
#Override
protected void onProgressUpdate(String... values) {
super.onProgressUpdate(values);
}
#Override
protected void onPostExecute(String s) {
((MainActivity)activity).hideUploader();
List<Student> students= StudentJasonParser.getObjectFromJason(s);
if (students != null) {
((MainActivity) activity).DisplyOnTextView(students);
}
}
}
this line : ((MainActivity)activity).DisplyOnTextView(students);
will return the fetched data to the main class in the following function (mentioned in the main class ! )
public void DisplyOnTextView(List< Student > students) {
List <Student> my = students ;
}
now what i want is to pass this list to the following class in order to use it in the imageView and textView in the viewPager instead of the pre-defined data in the class :
public class CustomAdapter extends PagerAdapter {
private int[] images = {R.drawable.sample_0,R.drawable.sample_1};
private Context ctx;
private LayoutInflater LayoutInflater;
public CustomAdapter(Context ctx)
{
this.ctx=ctx;
}
#Override
public int getCount() {
return images.length;
}
#Override
public boolean isViewFromObject(View view, Object object) {
return (view==(LinearLayout)object);
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
LayoutInflater = (LayoutInflater)ctx.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = LayoutInflater.inflate(R.layout.slide_layout,container,false);
ImageView imageView =(ImageView) view.findViewById(R.id.image_view);
TextView textView = (TextView)view.findViewById(R.id.image_count);
imageView.setImageResource(images[position]);
textView.setText(""+position);
container.addView(view);
return view;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((LinearLayout) object);
}
}
any idea ?!
thanks, regards.
what i want is to pass this list to the following class in order to use it in the imageView and textView in the viewPager
Then simply pass in the list as a parameter to the adapter and add a member variable for it. The usage of this adapter is at the bottom of this post, because I want to mention some other stuff.
class CustomAdapter extends PagerAdapter {
private Context ctx;
private List<Student> data;
public CustomAdapter(Context ctx, List<Student> students) {
this.ctx = ctx;
this.data = students;
}
If you want to use that data variable in the instantiateItem method, then you can do Student s = this.data.get(position); and use the various methods on the Student object to load the TextView or ImageView.
Please note that you will need an image loading library (Picasso, Glide, Fresco, etc.) to load a URL into an ImageView. While on the topic of libraries, though, you will save yourself much development time by looking into Gson for JSON parsing and Retrofit or Volley for HTTP network calls with JSON data.
As for your usage of the AsyncTask, passing around the Activity variable is bad practice. Try to use an asynchronous callback to the Activity instead.
public interface AsyncResponse<T> {
void onResponse(T response);
}
public class ConnectionAsyncTask extends AsyncTask<String, Void, List<Student>> {
private AsyncResponse<List<Student>> callback;
public ConnectionAsyncTask(AsyncResponse<List<Student>> callback) {
this.callback = callback;
}
#Override
protected List<User> doInBackground(String... params) {
String url = params[0];
final List<Student> students = new ArrayList<Student>();
// TODO: JSON stuff
return students;
}
#Override
protected void onPostExecute(List<Student> result) {
if (this.callback != null) {
this.callback.onResponse(result);
} else {
Log.w("ConnectionAsyncTask", "Ignoring result");
}
}
}
public class SampleViewPagerActivity extends Activity {
private ViewPager pager;
private PagerAdapter adapter;
private ArrayList<Student> students;
private ProgressDialog progress;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// 1. Inflate a layout
setContentView(R.layout.viewpager_activity);
// 2. Initialize the views
this.pager = (ViewPager) findViewById(R.id.pager);
this.progress = new ProgressDialog(this);
this.progress.setTitle("Loading");
this.progress.setMessage("Please wait");
// 3. Populate the views with data
this.students = new ArrayList<Student>();
this.adapter = new CustomAdapter(this, students);
this.pager.setAdapter(adapter);
// This code runs later, after 'execute' is called and the response is returned
ConnectionAsyncTask task = new ConnectionAsyncTask(new AsyncResponse<List<Student>>() {
#Override
public void onResponse(List<Student> response) {
students.clear();
students.addAll(response);
adapter.notifyDataSetChanged();
progress.hide();
}
});
// Optionally show some progress while waiting
this.progress.show();
// TODO: Use real URL
task.execute("http://www.somesite.com/data");
}
}
I am working on a RecyclerView which must be Draggable & swipeable. Everything works perfect.
The Data is getting Fetched in one class called ExerciseDataProvider & the RV code is another Fragment RecyclerListViewFragment.
The problem is that i can't notify Data changed from the FetchExercise on postExecute method. So the Data's are not getting populated in the RV.
Please Guide me in a Right Direction.
ACTIVITY
public class DraggableSwipeableExampleActivity extends AppCompatActivity {
private static final String FRAGMENT_TAG_DATA_PROVIDER = "data provider";
private static final String FRAGMENT_LIST_VIEW = "list view";
private static final String FRAGMENT_TAG_ITEM_PINNED_DIALOG = "item pinned dialog";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_demo);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(new ExampleDataProviderFragment(), FRAGMENT_TAG_DATA_PROVIDER)
.commit();
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new RecyclerListViewFragment(), FRAGMENT_LIST_VIEW)
.commit();
}
}
public AbstractDataProvider getDataProvider() {
final Fragment fragment = getSupportFragmentManager().findFragmentByTag(FRAGMENT_TAG_DATA_PROVIDER);
return ((ExampleDataProviderFragment) fragment).getDataProvider();
}
DATA PROVIDER
public class ExerciseDataProvider extends AbstractDataProvider {
private List<ConcreteData> mData;
private ConcreteData mLastRemovedData;
private int mLastRemovedPosition = -1;
public ExerciseDataProvider() {
new FetchExercise().execute();
mData = new LinkedList<>();
}
class FetchExercise extends AsyncTask<Void,Void,Void> {
#Override
protected Void doInBackground(Void... params) {
final int viewType = 0;
final int swipeReaction = RecyclerViewSwipeManager.REACTION_CAN_SWIPE_UP | RecyclerViewSwipeManager.REACTION_CAN_SWIPE_DOWN;
String url = "https://gist.githubusercontent.com/fake/cb9aa5494e7ee36ac3ca/raw/a4abfd19368063/exercise.JSON";
Log.d("Path", url);
try {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder().url(url).build();
Response response = client.newCall(request).execute();
String jsonData = response.body().string();
try {
JSONArray jsonArray = new JSONArray(jsonData);
for (int i = 0; i < jsonArray.length(); i++) {
final long id = i;
JSONObject jsonObject = jsonArray.getJSONObject(i);
String exercise_name = jsonObject.getString("name");
int exercise_duration = jsonObject.getInt("duration");
mData.add(new ConcreteData(id, viewType, exercise_name, exercise_duration, swipeReaction));
Log.d("exercise_name", exercise_name);
}
} catch (JSONException e) {
e.printStackTrace();
}
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
}
}
#Override
public int getCount() {
return mData.size();
}
#Override
public Data getItem(int index) {
if (index < 0 || index >= getCount()) {
throw new IndexOutOfBoundsException("index = " + index);
}
return mData.get(index);
}
#Override
public int undoLastRemoval() {
if (mLastRemovedData != null) {
int insertedPosition;
if (mLastRemovedPosition >= 0 && mLastRemovedPosition < mData.size()) {
insertedPosition = mLastRemovedPosition;
} else {
insertedPosition = mData.size();
}
mData.add(insertedPosition, mLastRemovedData);
mLastRemovedData = null;
mLastRemovedPosition = -1;
return insertedPosition;
} else {
return -1;
}
}
#Override
public void moveItem(int fromPosition, int toPosition) {
if (fromPosition == toPosition) {
return;
}
final ConcreteData item = mData.remove(fromPosition);
mData.add(toPosition, item);
mLastRemovedPosition = -1;
}
#Override
public void removeItem(int position) {
//noinspection UnnecessaryLocalVariable
final ConcreteData removedItem = mData.remove(position);
mLastRemovedData = removedItem;
mLastRemovedPosition = position;
}
public static final class ConcreteData extends Data {
private final long mId;
private final String mText;
private final int mViewType;
private final int mDuration;
private boolean mPinned;
ConcreteData(long id, int viewType, String text, int duration, int swipeReaction) {
mId = id;
mViewType = viewType;
mText = text;
mDuration = duration;
}
#Override
public int getViewType() {
return mViewType;
}
#Override
public int getDuration() {
return mDuration;
}
#Override
public long getId() {
return mId;
}
#Override
public String toString() {
return mText;
}
#Override
public String getText() {
return mText;
}
#Override
public boolean isPinned() {
return mPinned;
}
#Override
public void setPinned(boolean pinned) {
mPinned = pinned;
}
}
}
RecyclerListViewFragment
public class RecyclerListViewFragment extends Fragment {
private RecyclerView mRecyclerView;
private RecyclerView.LayoutManager mLayoutManager;
private RecyclerView.Adapter mAdapter;
private RecyclerView.Adapter mWrappedAdapter;
private RecyclerViewDragDropManager mRecyclerViewDragDropManager;
private RecyclerViewSwipeManager mRecyclerViewSwipeManager;
private RecyclerViewTouchActionGuardManager mRecyclerViewTouchActionGuardManager;
public RecyclerListViewFragment() {
super();
}
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_recycler_list_view, container, false);
}
#Override
public void onViewCreated(View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
//noinspection ConstantConditions
mRecyclerView = (RecyclerView) getView().findViewById(R.id.recycler_view);
mLayoutManager = new LinearLayoutManager(getContext());
// touch guard manager (this class is required to suppress scrolling while swipe-dismiss animation is running)
mRecyclerViewTouchActionGuardManager = new RecyclerViewTouchActionGuardManager();
mRecyclerViewTouchActionGuardManager.setInterceptVerticalScrollingWhileAnimationRunning(true);
mRecyclerViewTouchActionGuardManager.setEnabled(true);
// drag & drop manager
mRecyclerViewDragDropManager = new RecyclerViewDragDropManager();
mRecyclerViewDragDropManager.setDraggingItemShadowDrawable(
(NinePatchDrawable) ContextCompat.getDrawable(getContext(), R.drawable.material_shadow_z3));
// swipe manager
mRecyclerViewSwipeManager = new RecyclerViewSwipeManager();
//adapter
final MyDraggableSwipeableItemAdapter myItemAdapter = new MyDraggableSwipeableItemAdapter(getDataProvider());
myItemAdapter.setEventListener(new MyDraggableSwipeableItemAdapter.EventListener() {
#Override
public void onItemRemoved(int position) {
((DraggableSwipeableExampleActivity) getActivity()).onItemRemoved(position);
}
#Override
public void onItemViewClicked(View v, boolean pinned) {
onItemViewClick(v, pinned);
}
});
mAdapter = myItemAdapter;
mWrappedAdapter = mRecyclerViewDragDropManager.createWrappedAdapter(myItemAdapter); // wrap for dragging
mWrappedAdapter = mRecyclerViewSwipeManager.createWrappedAdapter(mWrappedAdapter); // wrap for swiping
final GeneralItemAnimator animator = new SwipeDismissItemAnimator();
animator.setSupportsChangeAnimations(false);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mWrappedAdapter); // requires *wrapped* adapter
mRecyclerView.setItemAnimator(animator);
// additional decorations
//noinspection StatementWithEmptyBody
if (supportsViewElevation()) {
// Lollipop or later has native drop shadow feature. ItemShadowDecorator is not required.
} else {
mRecyclerView.addItemDecoration(new ItemShadowDecorator((NinePatchDrawable) ContextCompat.getDrawable(getContext(), R.drawable.material_shadow_z1)));
}
mRecyclerView.addItemDecoration(new SimpleListDividerDecorator(ContextCompat.getDrawable(getContext(), R.drawable.list_divider_h), true));
mRecyclerViewTouchActionGuardManager.attachRecyclerView(mRecyclerView);
mRecyclerViewSwipeManager.attachRecyclerView(mRecyclerView);
mRecyclerViewDragDropManager.attachRecyclerView(mRecyclerView);
}
#Override
public void onPause() {
mRecyclerViewDragDropManager.cancelDrag();
super.onPause();
}
#Override
public void onDestroyView() {
if (mRecyclerViewDragDropManager != null) {
mRecyclerViewDragDropManager.release();
mRecyclerViewDragDropManager = null;
}
if (mRecyclerViewSwipeManager != null) {
mRecyclerViewSwipeManager.release();
mRecyclerViewSwipeManager = null;
}
if (mRecyclerViewTouchActionGuardManager != null) {
mRecyclerViewTouchActionGuardManager.release();
mRecyclerViewTouchActionGuardManager = null;
}
if (mRecyclerView != null) {
mRecyclerView.setItemAnimator(null);
mRecyclerView.setAdapter(null);
mRecyclerView = null;
}
if (mWrappedAdapter != null) {
WrapperAdapterUtils.releaseAll(mWrappedAdapter);
mWrappedAdapter = null;
}
mAdapter = null;
mLayoutManager = null;
super.onDestroyView();
}
private void onItemViewClick(View v, boolean pinned) {
int position = mRecyclerView.getChildAdapterPosition(v);
if (position != RecyclerView.NO_POSITION) {
((DraggableSwipeableExampleActivity) getActivity()).onItemClicked(position);
}
}
public AbstractDataProvider getDataProvider() {
return ((DraggableSwipeableExampleActivity) getActivity()).getDataProvider();
}
public void notifyItemChanged(int position) {
mAdapter.notifyItemChanged(position);
}
public void notifyItemInserted(int position) {
mAdapter.notifyItemInserted(position);
mRecyclerView.scrollToPosition(position);
}
}
To update recyclerView from onPostExecute in a data provider class, your onPostExecute should have access to context where your recyclerView is defined.
Since your FetchExercise async task is defined inside ExerciseDataProvider class, try passing activity context to ExerciseDataProvider's constructor and then pass it on to FetchExercise async task as described here: getting context in AsyncTask
public class MyCustomTask extends AsyncTask<Void, Void, Long> {
private Context mContext;
public MyCustomTask (Context context){
mContext = context;
}
protected void onPostExecute(Long result) {
//use mContext to update recycler view
}
}
}
Use the context to update the recyclerView.
UPDATE
Step 1
Define an interface that will notify your activity of data set change inside a class that initialises your data provider class and pass activity context to constructor of data provider class.
public class ExampleDataProviderFragment extends Fragment {
private AbstractDataProvider mDataProvider;
//Define an interface that will notify your activity of data set change
public interface EventListener {
void onNotifyDataSetChanged();
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setRetainInstance(true);
//Pass activity context to ExerciseDataProvider
mDataProvider = new ExerciseDataProvider(getActivity());
}
public AbstractDataProvider getDataProvider() {
return mDataProvider;
}
}
Step 2
Add context parameter to ExerciseDataProvider's constructor and use it to notify activity that implements your interface to notify dataset change.
public class ExerciseDataProvider extends AbstractDataProvider {
private List<ConcreteData> mData;
private ConcreteData mLastRemovedData;
private int mLastRemovedPosition = -1;
//Add context parameter to constructor
public ExerciseDataProvider(Context context) {
//Pass context to async task
new FetchExercise(context).execute();
mData = new LinkedList<>();
}
class FetchExercise extends AsyncTask<Void,Void,Integer> {
Context mContext;
public FetchExercise(Context context) {
mContext = context;
}
#Override
protected Integer doInBackground(Void... params) {
...
return 1;
}
#Override
protected void onPostExecute(Integer result) {
super.onPostExecute(result);
//Typecast context to interface defined above
//and notify dataset changes by calling its method
ExampleDataProviderFragment.EventListener eventListener = (ExampleDataProviderFragment.EventListener)mContext;
eventListener.onNotifyDataSetChanged();
}
}
}
Step 3
Implement above defined interface in your activity class and notify recyclerview adapter inside it
public class DraggableSwipeableExampleActivity extends AppCompatActivity
implements ExampleDataProviderFragment.EventListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
...
}
//implement interface method and notify recyclerview of changes
#Override
public void onNotifyDataSetChanged() {
Fragment fragment = getSupportFragmentManager().findFragmentByTag(FRAGMENT_LIST_VIEW);
// you might need to change visibility of `mWrappedAdapter` in the fragment that defines it or create a getter for it so that you can access it here
((RecyclerListViewFragment) fragment).mWrappedAdapter.notifyDataSetChanged();
}
...
}
I think #random is correct you should be notifying your Recycle view on post execute.
#Override
protected void onPostExecute(Void aVoid) {
mRecyclerViewAdapter.notifyDataSetChanged();
super.onPostExecute(aVoid);
}
or if you have done something in your async task to add/delete something in the data set you would do:
#Override
protected void onPostExecute(Void aVoid) {
mRecyclerViewAdapter.notifyItemRemoved(itemposition); // or item added
mRecyclerViewAdapter.notifyDataSetChanged();
super.onPostExecute(aVoid);
}
Hope it helps !
I'm new in Android and I have following code that shows the list of item in Adapter.
I have Four Different Adapter from where I am calling one comman AsyncTask to update Result. I have implemented one Interface ApiResponse and overrides apiResponseProcessing() to get result.
In Item of List "Add to Cart" Button Added in every row. OnClick of that button I am requesting to server. On Success of that response i want to update Button with "Added To Cart".
I have question How to update that string which is binded in onBindViewHolder(). I am getting success in that method but dont know how to update clicked Button from that method.
Here's my Adapter
/**
* Adapter
**/
public class AlbumPhotoDetailAdapter
extends RecyclerView.Adapter<AlbumPhotoDetailAdapter.ViewHolder> implements ApiResponse {
private final ArrayList<Photo> mValues;
Album album;
private Activity mContext;
private int mMemberId;
public AlbumPhotoDetailAdapter(Activity context, ArrayList<Photo> items) {
mValues = items;
this.mContext = context;
mMemberId = MemberPreference.getMemberId(mContext);
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.album_photo_detail_sub_view, parent, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
final Photo photo = mValues.get(position);
/**
* Album Owner Name
*/
String mOwnerName = photo.getOwnerName();
String mOwnerProfilePic = photo.getOwnerImage();
String mDateTime = photo.getDatetime();
String mPrice = String.valueOf(photo.getPrice());
/**
* Price String
*/
String priceStr = String.format(mContext.getString(R.string.string_dollar_price), mPrice);
holder.mAlbumPhotoDetailPhotoPrice.setText(priceStr);
/**
* Main Image
*/
Picasso.with(mContext).load(photo.getLink())
.error(R.drawable.ic_place_holder_circle)
.placeholder(R.drawable.ic_place_holder_circle)
.transform(new ImageTransformation(holder.mAlbumPhotoDetailSubMainImage))
.into(holder.mAlbumPhotoDetailSubMainImage);
/**
* Owner Name and Profile Pic
*/
holder.mAlbumPhotoDetailSubOwnerNameTextView.setText(mOwnerName);
Picasso.with(mContext).load(mOwnerProfilePic)
.error(R.drawable.ic_place_holder_circle)
.placeholder(R.drawable.ic_place_holder_circle)
.resize(100, 100)
.transform(new CircleTransform())
.into(holder.mAlbumPhotoDetailSubOwnerImage);
mDateTime = mDateTime != null ? DateUtils.getNiceTime(mDateTime) : "----";
holder.mAlbumPhotoDetailSubOwnerPostedTimeTextView.setText(mDateTime);
// Photo Add to cart.
holder.mAddToCartButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(InternetConnection.checkConnection(mContext)) {
new BackgroundAsyncTask(mContext, (ApiResponse) mContext, mMemberId, photo.getId()).execute();
} else {
DailyStudio.noInternetConnectionToast(mContext);
}
}
});
}
#Override
public int getItemCount() {
return mValues.size();
}
#Override
public void apiResponseProcessing(String response) {
Log.i(TAG,"Api Response : "+response);
if(response.equals(Fields.JSON_SUCCESS)) {
}
}
/**
* View Holder
*/
public static class ViewHolder extends RecyclerView.ViewHolder {
public final View mView;
private ImageView mAlbumPhotoDetailSubOwnerImage;
private ImageView mAlbumPhotoDetailSubMainImage;
private TextView mAlbumPhotoDetailSubOwnerNameTextView;
private TextView mAlbumPhotoDetailSubOwnerPostedTimeTextView;
private TextView mAlbumPhotoDetailPhotoPrice;
private TextView mAlbumPhotoDetailSubDescription;
private Button mAddToCartButton;
public ViewHolder(View view) {
super(view);
mView = view;
mAlbumPhotoDetailSubOwnerImage = (ImageView) view.findViewById(R.id.album_photo_detail_sub_owner_image);
mAlbumPhotoDetailSubMainImage = (ImageView) view.findViewById(R.id.album_photo_detail_sub_main_image);
mAlbumPhotoDetailSubOwnerNameTextView = (TextView) view.findViewById(R.id.album_photo_detail_sub_owner_name_text_view);
mAlbumPhotoDetailSubOwnerPostedTimeTextView = (TextView) view.findViewById(R.id.album_photo_detail_sub_owner_posted_time_text_view);
mAlbumPhotoDetailPhotoPrice = (TextView) view.findViewById(R.id.album_photo_detail_photo_price);
mAlbumPhotoDetailSubDescription = (TextView) view.findViewById(R.id.album_photo_detail_sub_description);
mAddToCartButton = (Button) view.findViewById(R.id.album_photo_detail_photo_add_to_cart_button);
}
}
}
Here's my Interface
/**
* Interface..
*/
public interface ApiResponse {
public void apiResponseProcessing(String response);
}
Here's my Background AsyncTask
/**
* Background AsyncTask...
*/
public class BackgroundAsyncTask extends AsyncTask<Void, Void, String> {
private Context context;
private String accessToken;
private int memberId;
private int photoId;
private ApiResponse objIBaseApi;
public BackgroundAsyncTask(Context context, ApiResponse apiResponse, int memberId, int photoId) {
this.context = context;
this.memberId = memberId;
this.photoId = photoId;
accessToken = MemberPreference.getAccessToken(context);
this.objIBaseApi = apiResponse;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected String doInBackground(Void... params) {
JSONObject json = JSONParser.addToCartPhoto(accessToken, memberId, photoId);
if(json != null) {
Log.i(TAG,"First Json : "+json.toString());
try {
if (json.getString(Fields.RESULT).equalsIgnoreCase(Fields.JSON_SUCCESS)) {
return Fields.JSON_SUCCESS;
} else if(json.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
String refreshToken = MemberPreference.getRefreshToken(context);
JSONObject newJSONObject = JSONParser.loginMemberWithRefreshToken(refreshToken, Integer.toString(memberId));
if(newJSONObject != null) {
if(newJSONObject.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
return Fields.ERROR_ACCESS_DENIED;
} else {
return Fields.JSON_SUCCESS;
}
} else
return Fields.ERROR_ACCESS_DENIED;
} else {
return Fields.JSON_ERROR;
}
} catch (JSONException e) {
e.printStackTrace();
return Fields.JSON_ERROR;
}
}
return Fields.JSON_ERROR;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
objIBaseApi.apiResponseProcessing(result);
}
}
Is there any solution or better way to do like this?
Your help would be appreciated. Thank you.
You Can keep one flag isAddedToCart variable in you bean class which you are using in your adapter(Photo). Now just pass the position in your asynctask once user click on "add to cart" button. On getting the successful you just need to find the bean from the list of bean you passed in adapter and change the flag isAddedToCart to true and notify your adapter thats it. Here is the code snippet:-
Photo Class
public class Photo{
private boolean isAddedToCart;
public void setAddedTOCart(boolean isAdded){
isAddedToCart = isAdded;
}
public boolean isAddedToCart(){
return isAddedToCart;
}
}
AlbumPhotoDetailAdapter onBindViewHolder
#Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
final Photo photo = mValues.get(position);
/**
* Album Owner Name
*/
String mOwnerName = photo.getOwnerName();
String mOwnerProfilePic = photo.getOwnerImage();
String mDateTime = photo.getDatetime();
String mPrice = String.valueOf(photo.getPrice());
String isAdded = photo.isAddedToCart();
/**
* Price String
*/
String priceStr = String.format(mContext.getString(R.string.string_dollar_price), mPrice);
holder.mAlbumPhotoDetailPhotoPrice.setText(priceStr);
/**
* Main Image
*/
Picasso.with(mContext).load(photo.getLink())
.error(R.drawable.ic_place_holder_circle)
.placeholder(R.drawable.ic_place_holder_circle)
.transform(new ImageTransformation(holder.mAlbumPhotoDetailSubMainImage))
.into(holder.mAlbumPhotoDetailSubMainImage);
/**
* Owner Name and Profile Pic
*/
holder.mAlbumPhotoDetailSubOwnerNameTextView.setText(mOwnerName);
Picasso.with(mContext).load(mOwnerProfilePic)
.error(R.drawable.ic_place_holder_circle)
.placeholder(R.drawable.ic_place_holder_circle)
.resize(100, 100)
.transform(new CircleTransform())
.into(holder.mAlbumPhotoDetailSubOwnerImage);
mDateTime = mDateTime != null ? DateUtils.getNiceTime(mDateTime) : "----";
holder.mAlbumPhotoDetailSubOwnerPostedTimeTextView.setText(mDateTime);
if(isAdded){
holder.mAddToCartButton.setText("Added TO Cart");
}else{
holder.mAddToCartButton.setText("Add TO Cart");
}
// Photo Add to cart.
holder.mAddToCartButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(InternetConnection.checkConnection(mContext)) {
new BackgroundAsyncTask(mContext, (ApiResponse) mContext, mMemberId, photo.getId(),position).execute();
} else {
DailyStudio.noInternetConnectionToast(mContext);
}
}
});
}
your Interface
public interface ApiResponse {
public void apiResponseProcessing(String response,int position);
}
Your Adapter apiResponceProcessing()
#Override
public void apiResponseProcessing(String response,int position) {
Log.i(TAG,"Api Response : "+response);
if(response.equals(Fields.JSON_SUCCESS)) {
mValues.get(position).setAddedTOCart(true);
notifyDataSetChange();
}
}
And finally your
BackgroundAsyncTask
public class BackgroundAsyncTask extends AsyncTask<Void, Void, String> {
private Context context;
private String accessToken;
private int memberId;
private int photoId;
private int mPosition;
private ApiResponse objIBaseApi;
public BackgroundAsyncTask(Context context, ApiResponse apiResponse, int memberId, int photoId,int position) {
this.context = context;
this.memberId = memberId;
this.photoId = photoId;
accessToken = MemberPreference.getAccessToken(context);
this.objIBaseApi = apiResponse;
this.mPosition = position;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected String doInBackground(Void... params) {
JSONObject json = JSONParser.addToCartPhoto(accessToken, memberId, photoId);
if(json != null) {
Log.i(TAG,"First Json : "+json.toString());
try {
if (json.getString(Fields.RESULT).equalsIgnoreCase(Fields.JSON_SUCCESS)) {
return Fields.JSON_SUCCESS;
} else if(json.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
String refreshToken = MemberPreference.getRefreshToken(context);
JSONObject newJSONObject = JSONParser.loginMemberWithRefreshToken(refreshToken, Integer.toString(memberId));
if(newJSONObject != null) {
if(newJSONObject.getString(Fields.JSON_ERROR).equalsIgnoreCase(Fields.ERROR_ACCESS_DENIED)) {
return Fields.ERROR_ACCESS_DENIED;
} else {
return Fields.JSON_SUCCESS;
}
} else
return Fields.ERROR_ACCESS_DENIED;
} else {
return Fields.JSON_ERROR;
}
} catch (JSONException e) {
e.printStackTrace();
return Fields.JSON_ERROR;
}
}
return Fields.JSON_ERROR;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
objIBaseApi.apiResponseProcessing(result,mPosition);
}
}
Firstly in my opinion adapter should not care about network request. But
giving an answer in substance, you can try pass anonymous class for your apiResponseProcessing in same manner as you create OnClickListener for your button. It can look like this:
holder.mAddToCartButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(InternetConnection.checkConnection(mContext)) {
new BackgroundAsyncTask(
mContext,
new ApiResponse() {
#Override
public void apiResponseProcessing(String response) {
Log.i(TAG,"Api Response : "+response);
if(response.equals(Fields.JSON_SUCCESS)) {
// Here you can access you holder till it final
}
}
},
mMemberId,
photo.getId()).execute();
} else {
DailyStudio.noInternetConnectionToast(mContext);
}
}
});
But code like this looks messy and spaghetti. As i say at the beginning there are exist at least one different approach to handle changes for buttons inside listview/recivleview. I use method, where adapter only care about building interface with given data and delegate buttons clicks to someone else (in most cases activity that contains listview). An easy way notify activity about button click is Bus messaging pattern. I use Otto event library. When delegate receive notification about button click, it can initiate data changing according current task and then initiate listview reloading or partial update only required rows.
Additional comments
Try to write beautiful code. Constructor AlbumPhotoDetailAdapter has different syntax to assign instance variables. One with this keyword and other without. Usually you should use one way.
public AlbumPhotoDetailAdapter(Activity context, ArrayList<Photo> items) {
this.values = items;
this.context = context;
this.memberId = MemberPreference.getMemberId(context);
}
album instance variable have no access modifiers indication. You should know, that in java programming language omitting access specifiers is not the same as private modifier.