Develop Reference

Can't pass null for argument 'pathString' in child() error

ModelOrderUser.java
package my.anupamroy.smartcanteenapp.models;
public class ModelOrderUser {
String orderId,orderTime,orderStatus,orderCost,orderBy,orderTo;
public ModelOrderUser(){
}
public ModelOrderUser(String orderId, String orderTime, String orderStatus, String orderCost, String orderBy, String orderTo) {
this.orderId = orderId;
this.orderTime = orderTime;
this.orderStatus = orderStatus;
this.orderCost = orderCost;
this.orderBy = orderBy;
this.orderTo = orderTo;
}
public String getOrderId() {
return orderId;
}
public void setOrderId(String orderId) {
this.orderId = orderId;
}
public String getOrderTime() {
return orderTime;
}
public void setOrderTime(String orderTime) {
this.orderTime = orderTime;
}
public String getOrderStatus() {
return orderStatus;
}
public void setOrderStatus(String orderStatus) {
this.orderStatus = orderStatus;
}
public String getOrderCost() {
return orderCost;
}
public void setOrderCost(String orderCost) {
this.orderCost = orderCost;
}
public String getOrderBy() {
return orderBy;
}
public void setOrderBy(String orderBy) {
this.orderBy = orderBy;
}
public String getOrderTo() {
return orderTo;
}
public void setOrderTo(String orderTo) {
this.orderTo = orderTo;
}
}
AdapterOrderUser.java
package my.anupamroy.smartcanteenapp.adapters;
import android.content.Context;
import android.text.Layout;
import android.text.format.DateFormat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import java.util.ArrayList;
import java.util.Calendar;
import my.anupamroy.smartcanteenapp.R;
import my.anupamroy.smartcanteenapp.models.ModelOrderUser;
public class AdapterOrderUser extends RecyclerView.Adapter<AdapterOrderUser.HolderOrderUser>{
private Context context;
private ArrayList<ModelOrderUser> orderUserList;
public AdapterOrderUser(Context context, ArrayList<ModelOrderUser> orderUserList) {
this.context = context;
this.orderUserList = orderUserList;
}
#NonNull
#Override
public HolderOrderUser onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
//inflate layout
View view = LayoutInflater.from(context).inflate(R.layout.row_order_user,parent,false);
return new HolderOrderUser(view);
}
#Override
public void onBindViewHolder(#NonNull HolderOrderUser holder, int position) {
//get data
ModelOrderUser modelOrderUser=orderUserList.get(position);
String orderId = modelOrderUser.getOrderId();
String orderBy = modelOrderUser.getOrderBy();
String orderCost = modelOrderUser.getOrderCost();
String orderStatus = modelOrderUser.getOrderStatus();
String orderTime = modelOrderUser.getOrderTime();
String orderTo = modelOrderUser.getOrderTo();
//get shop info
loadShopInfo(modelOrderUser,holder);
//set data
holder.amountTv.setText("Amount: ₹" +orderCost);
holder.statusTv.setText(orderStatus);
holder.orderIdTv.setText("OrderID:"+orderId);
// change order status text color
if(orderStatus.equals("In Progress")){
holder.statusTv.setTextColor(context.getResources().getColor(R.color.colorPrimary));
}
else if(orderStatus.equals("Completed")){
holder.statusTv.setTextColor(context.getResources().getColor(R.color.colorGreen));
}
else if(orderStatus.equals("Cancelled")){
holder.statusTv.setTextColor(context.getResources().getColor(R.color.colorRed));
}
//convert timestamp to proper format
Calendar calendar =Calendar.getInstance();
calendar.setTimeInMillis(Long.parseLong(orderTime));
String formatedDate= DateFormat.format("dd/MM/yyy",calendar).toString();
holder.dateTv.setText(formatedDate);
}
private void loadShopInfo(ModelOrderUser modelOrderUser, final HolderOrderUser holder) {
DatabaseReference ref = FirebaseDatabase.getInstance().getReference("Users");
ref.child(modelOrderUser.getOrderTo())
.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
String shopName =""+dataSnapshot.child("shopName").getValue();
holder.shopNameTv.setText(shopName);
}
#Override
public void onCancelled(#NonNull DatabaseError error) {
}
});
}
#Override
public int getItemCount() {
return orderUserList.size();
}
//view holder class
class HolderOrderUser extends RecyclerView.ViewHolder{
private TextView orderIdTv,dateTv,shopNameTv,amountTv,statusTv;
public HolderOrderUser(#NonNull View itemView) {
super(itemView);
//init views of layout
orderIdTv=itemView.findViewById(R.id.orderIdTv);
dateTv=itemView.findViewById(R.id.dateTv);
shopNameTv=itemView.findViewById(R.id.shopNameTv);
amountTv=itemView.findViewById(R.id.amountTv);
statusTv=itemView.findViewById(R.id.statusTv);
}
}
}
I am facing the following while executing don't know what is happening
java.lang.NullPointerException: Can't pass null for argument 'pathString' in child()
at com.google.firebase.database.DatabaseReference.child(DatabaseReference.java:96)
at my.anupamroy.smartcanteenapp.adapters.AdapterOrderUser.loadShopInfo(AdapterOrderUser.java:84)
at my.anupamroy.smartcanteenapp.adapters.AdapterOrderUser.onBindViewHolder(AdapterOrderUser.java:56)
at my.anupamroy.smartcanteenapp.adapters.AdapterOrderUser.onBindViewHolder(AdapterOrderUser.java:26)
Please help me out with this error
don't know why the code is throwing errors for me
please help me out
I am getting errors in lines number 84,56,26

How to store data from REST API with Volley for Android

I try to get data from my Api, I can get data and convert it into an object class I created and show it but I can't store all objects instances in an list. Someone knows ?
I tried to add every element I got in a List then try to get elements from it after but doesn't work, the list stays empty.
This is what my API returns :
{"_id":"60683c5bcdfcb74689bc8382","questionId":3,"question":"Question 3","choices":"1-/-2-/-3-/-4","category":"Other","difficulty":"Easy"}
This is my "ApiTest activity" :
package com.jojo.jojozquizz;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.JsonObjectRequest;
import com.android.volley.toolbox.Volley;
import com.jojo.jojozquizz.model.Question;
import com.jojo.jojozquizz.model.QuestionBank;
import com.jojo.jojozquizz.tools.APIListener;
import org.json.JSONException;
import org.json.JSONObject;
public class ApiTests extends AppCompatActivity implements APIListener {
private TextView text;
public static final String TAG = "MyTag";
private QuestionBank mQuestionBank;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_api_tests);
mQuestionBank = new QuestionBank();
text = findViewById(R.id.api_text);
String url = "https://nextfor.studio/questions/test";
getQuestionFromApi(url);
}
private void getQuestionFromApi(String url) {
APIListener listener = this;
RequestQueue requestQueue = Volley.newRequestQueue(this);
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.GET, url, null, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
Log.d(TAG, "onResponse: " + response.toString());
Question question = new Question();
question.setId(response.getInt("questionId"));
question.setQuestion(response.getString("question"));
question.setChoices(response.getString("choices"));
question.setCategory(response.getString("category"));
question.setDifficulty(response.getString("difficulty"));
listener.questionReceived(question);
} catch (JSONException e) {
Log.i(TAG, e.getMessage());
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.d(TAG, "onErrorResponse: " + error.getMessage());
}
});
requestQueue.add(jsonObjectRequest);
}
#Override
public void questionReceived(Question q) {
mQuestionBank.addQuestion(q);
}
}
Question class :
package com.jojo.jojozquizz.model;
import androidx.room.ColumnInfo;
import androidx.room.Entity;
import androidx.room.Ignore;
import androidx.room.PrimaryKey;
import java.io.Serializable;
import java.util.List;
#Entity(tableName = "questions")
public class Question implements Serializable {
#PrimaryKey()
#ColumnInfo(name = "id")
private long id;
#ColumnInfo(name = "question")
private String mQuestion;
#Ignore
private List<String> mChoiceList;
#ColumnInfo(name = "choices")
private String mChoices;
#ColumnInfo(name = "answer_index")
private int mAnswerIndex;
#ColumnInfo(name = "categorie")
private String mCategory;
#Ignore
private String mTrueAnswer;
#ColumnInfo(name = "difficulty")
private String mDifficulty;
public Question() {
}
public Question(int id, String mQuestion, List<String> mChoiceList, String mCategorie, String mDifficulty) {
this.id = id;
this.mQuestion = mQuestion;
this.mChoices = mChoiceList.get(0) + "-/-" + mChoiceList.get(1) + "-/-" + mChoiceList.get(2) + "-/-" + mChoiceList.get(3);
this.mAnswerIndex = 0;
this.mCategory = mCategorie;
this.mDifficulty = mDifficulty;
}
public Question(String mQuestion, List<String> mChoiceList, String mCategorie, String mDifficulty) {
this.mQuestion = mQuestion;
this.mChoices = mChoiceList.get(0) + "-/-" + mChoiceList.get(1) + "-/-" + mChoiceList.get(2) + "-/-" + mChoiceList.get(3);
this.mAnswerIndex = 0;
this.mCategory = mCategorie;
this.mDifficulty = mDifficulty;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getQuestion() {
return mQuestion;
}
public void setQuestion(String question) {
mQuestion = question;
}
public List<String> getChoiceList() {
return mChoiceList;
}
public void setChoiceList(List<String> choiceList) {
mChoiceList = choiceList;
}
public String getChoices() {
return mChoices;
}
public void setChoices(String choices) {
mChoices = choices;
}
public void setAnswerIndex(int mAnswerIndex) {
this.mAnswerIndex = mAnswerIndex;
}
public int getAnswerIndex() {
return mAnswerIndex;
}
public String getCategory() {
return mCategory;
}
public void setCategory(String categorie) {
mCategory = categorie;
}
public String getTrueAnswer() {
return mTrueAnswer;
}
public void setTrueAnswer(String trueAnswer) {
mTrueAnswer = trueAnswer;
}
public String getDifficulty() {
return mDifficulty;
}
public void setDifficulty(String difficulty) {
mDifficulty = difficulty;
}
}
QuestionBank (this is like a list of Questions) :
package com.jojo.jojozquizz.model;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
public class QuestionBank {
private List<Question> mQuestionList;
public int mNextQuestionIndex;
public QuestionBank() {
mQuestionList = new LinkedList<>();
mNextQuestionIndex = 0;
}
public QuestionBank(List<Question> questionList, boolean shuffle) {
mQuestionList = questionList;
if (shuffle)
Collections.shuffle(mQuestionList);
mNextQuestionIndex = 0;
}
public Question getQuestion() {
if (mNextQuestionIndex == mQuestionList.size())
mNextQuestionIndex = 0;
return mQuestionList.get(mNextQuestionIndex++);
}
public Question getQuestion(int i) {
return mQuestionList.get(i);
}
public void reShuffle() {
Collections.shuffle(mQuestionList);
}
public void addQuestion(Question question) {
mQuestionList.add(question);
}
public int returnListSize() {
return mQuestionList.size();
}
}
And APIListener :
package com.jojo.jojozquizz.tools;
import com.jojo.jojozquizz.model.Question;
public interface APIListener {
void questionReceived(Question q);
}

API calling is an asynchronous process. So getQuestionFromApi(url); might took some time, so if you try text.setText(mQuestionBank.getQuestion(0).getQuestion()); after getQuestionFromApi(url); line, it won't work. You could use LiveData to handle this case. Like:
class QuestionBank {
MutableLiveData<List<Question>> mQuestionList;
public int mNextQuestionIndex;
public QuestionBank() {
mQuestionList = new MutableLiveData<>(new LinkedList<>());
mNextQuestionIndex = 0;
}
public QuestionBank(List<Question> questionList, boolean shuffle) {
mQuestionList.setValue(questionList);
if (shuffle)
Collections.shuffle(mQuestionList.getValue());
mNextQuestionIndex = 0;
}
public Question getQuestion() {
if (mNextQuestionIndex == mQuestionList.getValue().size())
mNextQuestionIndex = 0;
return mQuestionList.getValue().get(mNextQuestionIndex++);
}
public Question getQuestion(int i) {
return mQuestionList.getValue().get(i);
}
public void reShuffle() {
Collections.shuffle(mQuestionList.getValue());
}
public void addQuestion(Question question) {
List<Question> tempQ = mQuestionList.getValue();
tempQ.add(question);
mQuestionList.setValue(tempQ);
}
public int returnListSize() {
return mQuestionList.getValue().size();
}
}
And inside onCreate() observe if any data has been added or not and then setText() to TextView. Like:
QuestionBank questionBank = new QuestionBank();
questionBank.mQuestionList.observe(getViewLifecycleOwner(), new Observer<List<Question>>() {
#Override
public void onChanged(List<Question> questions) {
if (!questions.isEmpty()){
textView.setText(questions.get(0).getQuestion());
Log.d("TAG==>>","New Question added Total size = "+questions.size());
}
}
});

Sorting data in List by specific value

I have an issue where my recyclerview adds new items at the end, whereas I want the latest items at the top upon user refresh. I've been scratching around all over the net and it essentially boils down to adding setreverseLayout or setStackFromEnd. This gives other complications such as the recycler view not scrolling to the top to the latest item.
I then had a thought of maybe ordering my data list by a specific value and then it should return it as I want it. Can this be done and would it resolve my issue? I want to sort it by value adopt_rownum desc.
My Custom Adapter
package com.example.admin.paws;
import android.content.Context;
import android.content.Intent;
import android.graphics.Typeface;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import com.bumptech.glide.Glide;
import java.util.List;
/**
* Created by admin on 9/16/2016.
*/
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.ViewHolder> {
public Context context;
public List<MyData> my_data;
public CustomAdapter(Context context, List<MyData> my_data) {
this.context = context;
this.my_data = my_data;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.cardnew,parent,false);
return new ViewHolder(itemView);
}
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
String name = my_data.get(position).getName();
String age = my_data.get(position).getAge();
String gender = my_data.get(position).getGender();
String SubstAge = age.substring(0,age.indexOf("(") -1);
String NameAgeGender = name + ", " + SubstAge + ", " + gender;
holder.about.setText(my_data.get(position).getAbout());
holder.NameAgeGender.setText(NameAgeGender);
Glide.with(context).load(my_data.get(position).getPhoto_path()).into(holder.photo_path);
//activity_card_details vars
// final String about = my_data.get(position).getAbout();
final String adoptId = my_data.get(position).getId()+"";
final String photo_path_dtls = my_data.get(position).getPhoto_path();
final String listedDate = my_data.get(position).getDatetime_listed();
final String status = my_data.get(position).getStatus();
final String breed = my_data.get(position).getBreed();
final String source = my_data.get(position).getSource();
final String contact_info = my_data.get(position).getContact_info();
final String suburb = my_data.get(position).getSuburb();
final String city = my_data.get(position).getCity();
final String province = my_data.get(position).getProvince();
final String concat_location = suburb + ", " + city + ", " + province;
final String viewCounter = my_data.get(position).getViewCounter()+"";
//When click on photo
holder.photo_path.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(context,CardDetailsActivity.class);
intent.putExtra("listedDate",listedDate);
intent.putExtra("adoptId",adoptId);
// intent.putExtra("about",about);
intent.putExtra("status",status);
intent.putExtra("breed",breed);
intent.putExtra("source",source);
intent.putExtra("contactinfo",contact_info);
intent.putExtra("location",concat_location);
intent.putExtra("photo_path_dtls",photo_path_dtls);
intent.putExtra("viewCounter",viewCounter);
context.startActivity(intent);
}
});
}
#Override
public int getItemCount() {
return my_data.size();
}
public class ViewHolder extends RecyclerView.ViewHolder
{
public TextView NameAgeGender;
public ImageView photo_path;
public TextView about;
private ViewHolder(View itemView) {
super(itemView);
about = (TextView) itemView.findViewById(R.id.about);
NameAgeGender = (TextView) itemView.findViewById(R.id.tvNameAgeGender);
// NameAgeGender.setTextColor(Color.parseColor("#9C9393"));
Typeface typeface = Typeface.createFromAsset(context.getAssets(), "fonts/Lato-Medium.ttf");
NameAgeGender.setTypeface(typeface);
//NameAgeGender.setBackgroundColor(Color.parseColor("#F35959"));
photo_path = (ImageView) itemView.findViewById(R.id.photo_path);
}
}
}
My DataList
package com.example.admin.paws;
public class MyData {
//the must be in the same order of the select column order
public int adopt_rownum
,viewCounter
,adopt_id;
private String
name
,type
,breed
,age
,gender
,size
,about
,photo_path
,source
,contact_info
,suburb
,city
,province
,datetime_listed
,status;
public MyData(
int adopt_rownum,
int viewCounter,
int adopt_id,
String name,
String type,
String breed,
String age,
String gender,
String size,
String about,
String photo_path,
String source,
String contact_info,
String suburb,
String city,
String province,
String datetime_listed,
String status)
{
this.adopt_rownum = adopt_rownum;
this.viewCounter = viewCounter;
this.adopt_id = adopt_id;
this.name = name;
this.type = type;
this.breed = breed;
this.age = age;
this.gender = gender;
this.size = size;
this.about = about;
this.photo_path = photo_path;
this.source = source;
this.contact_info = contact_info;
this.suburb = suburb;
this.city = city;
this.province = province;
this.datetime_listed = datetime_listed;
this.status = status;
}
//adopt_rownum used for filtering the records.
public int getAdopt_rownum() {
return adopt_rownum;
}
//viewcounter
public int getViewCounter() {
return viewCounter;
}
//adopt_id
public int getId() {
return adopt_id;
}
public void setId(int adopt_id) {
this.adopt_id = adopt_id;
}
//name
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
//type
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
//breed
public String getBreed() {
return breed;
}
public void setBreed(String breed) {
this.breed = breed;
}
//age
public String getAge() {
return age;
}
public void setAge(String age) {
this.age = age;
}
//gender
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.age = gender;
}
//size
public String getSize() {
return size;
}
public void setSize(String size) {
this.size = size;
}
//about
public String getAbout() {
return about;
}
public void setAbout(String about) {
this.about = about;
}
//photo path
public String getPhoto_path() {
return photo_path;
}
public void setPhoto_path(String photo_path) {
this.photo_path = photo_path;
}
//source
public String getSource() {
return source;
}
public void setSource(String source) {
this.source = source;
}
//contact_info
public String getContact_info() {
return contact_info;
}
public void setContact_info(String contact_info) {
this.contact_info = contact_info;
}
//suburb
public String getSuburb() {
return suburb;
}
public void setSuburb(String suburb) {
this.contact_info = suburb;
}
//city
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
//province
public String getProvince() {
return province;
}
public void setProvince(String province) {
this.province = province;
}
//datetime_listed
public String getDatetime_listed() {
return datetime_listed;
}
public void setDatetime_listed(String datetime_listed) {
this.datetime_listed = datetime_listed;
}
//status
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
}
The fragment that displays the results. Another question on the side, inside this fragment for load_data_from_server its giving me a warning that "This Async task should be static or leaks might occur". I have no idea what this means since I'm completely new to JAVA.
package com.example.admin.paws;
import android.app.Activity;
import android.content.Context;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
/**
* A simple {#link Fragment} subclass.
* Activities that contain this fragment must implement the
* {#link feedFragment.OnFragmentInteractionListener} interface
* to handle interaction events.
* Use the {#link feedFragment#newInstance} factory method to
* create an instance of this fragment.
*/
public class feedFragment extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
public Activity FragActivity;
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
private List<MyData> data_list;
private CustomAdapter adapter;
RecyclerView recyclerView;
public String EndOfFeed;
private OnFragmentInteractionListener mListener;
public feedFragment() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* #param param1 Parameter 1.
* #param param2 Parameter 2.
* #return A new instance of fragment fragment_feed.
*/
// TODO: Rename and change types and number of parameters
public static feedFragment newInstance(String param1, String param2) {
feedFragment fragment = new feedFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
setHasOptionsMenu(true);
View rootView = inflater.inflate(R.layout.fragment_feed, container, false);
final GridLayoutManager gridLayoutManager;
final SwipeRefreshLayout swipeRefreshLayout = rootView.findViewById(R.id.feedRefresh);
TextView tvEndOfFeed = rootView.findViewById(R.id.tvEndOfFeed);
tvEndOfFeed.setText(EndOfFeed);
//recycler view
recyclerView = (RecyclerView) rootView.findViewById(R.id.recycler_view);
data_list = new ArrayList<>();
load_data_from_server(0, "getFeed.php");
gridLayoutManager = new GridLayoutManager(getActivity(), 1); //2 nr of cards next to each other
recyclerView.setLayoutManager(gridLayoutManager);
//gridLayoutManager.setReverseLayout(true);
adapter = new CustomAdapter(getActivity(), data_list);
recyclerView.setAdapter(adapter);
recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
#Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
if (gridLayoutManager.findLastCompletelyVisibleItemPosition() == data_list.size() - 1) {
load_data_from_server(data_list.get(data_list.size() - 1).getAdopt_rownum(), "getFeed.php");
}
}
});
swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
//this works but issue with the ordering of the adoptrownum
load_data_from_server(data_list.get(data_list.size() -1).getAdopt_rownum(), "refreshFeed.php");
swipeRefreshLayout.setRefreshing(false);
}
});
return rootView;
}
private void load_data_from_server(final int adopt_id, final String phpScript) {
AsyncTask<Integer,Void,Void> task = new AsyncTask<Integer, Void, Void>() {
#Override
protected Void doInBackground(Integer... integers) {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url("http://10.0.2.2/app_scripts/"+phpScript+"?adopt_rownum="+integers[0])
.build();
try {
Response response = client.newCall(request).execute();
JSONArray array = new JSONArray(response.body().string());
for (int i=0; i<array.length(); i++){
JSONObject object = array.getJSONObject(i);
MyData data = new MyData(
object.getInt("ADOPT_ROWNUM"),
object.getInt("VIEWCOUNTER"),
object.getInt("ADOPT_ID"),
object.getString("NAME"),
object.getString("TYPE"),
object.getString("BREED"),
object.getString("AGE"),
object.getString("GENDER"),
object.getString("SIZE"),
object.getString("ABOUT"),
object.getString("PHOTO_PATH"),
object.getString("SOURCE"),
object.getString("CONTACT_INFO"),
object.getString("SUBURB"),
object.getString("CITY"),
object.getString("PROVINCE"),
object.getString("DATETIME_LISTED"),
object.getString("STATUS")
);
data_list.add(data);
}
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
System.out.println("End of content"+e);
}
return null;
}
#Override
protected void onPostExecute(Void aVoid) {
adapter.notifyDataSetChanged();
}
};
task.execute(adopt_id);
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
I added the Comparator as instructed below but the output is a bit weird...
public class MyComparator implements Comparator<MyData > {
#Override
public int compare(final MyData o1, final MyData o2) {
Log.d("APP", "compare Starting... ");
Integer val1 = o1.getAdopt_rownum();
Log.d("APP", "compare val1... "+val1);
Integer val2 = o2.getAdopt_rownum();
Log.d("APP", "compare val1... "+val2);
Log.d("APP", "compare val1 and val2 ="+val1.compareTo(val2));
return val1.compareTo(val2);
}
}
output
compare Starting...
compare val1... 2
compare val2... 1
compare val1 and val2 =1
...
compare Starting...
compare val1... 14
compare val2... 15
compare val2 and val2 =1
Below is how i implemented it in my fragment
private void load_data_from_server(final int adopt_id, final String phpScript) {
AsyncTask<Integer,Void,Void> task = new AsyncTask<Integer, Void, Void>() {
#Override
protected Void doInBackground(Integer... integers) {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url("http://10.0.2.2/app_scripts/"+phpScript+"?adopt_rownum="+integers[0])
.build();
try {
Response response = client.newCall(request).execute();
JSONArray array = new JSONArray(response.body().string());
for (int i=0; i<array.length(); i++){
JSONObject object = array.getJSONObject(i);
MyData data = new MyData(
object.getInt("ADOPT_ROWNUM"),
object.getInt("VIEWCOUNTER"),
object.getInt("ADOPT_ID"),
object.getString("NAME"),
object.getString("TYPE"),
object.getString("BREED"),
object.getString("AGE"),
object.getString("GENDER"),
object.getString("SIZE"),
object.getString("ABOUT"),
object.getString("PHOTO_PATH"),
object.getString("SOURCE"),
object.getString("CONTACT_INFO"),
object.getString("SUBURB"),
object.getString("CITY"),
object.getString("PROVINCE"),
object.getString("DATETIME_LISTED"),
object.getString("STATUS")
);
data_list.add(data);
**Collections.sort(data_list,new MyComparator());**
}
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
//System.out.println("End of content"+e);
EndOfFeed = e+"";
}
return null;
}
#Override
protected void onPostExecute(Void aVoid) {
adapter.notifyDataSetChanged();
}
};
task.execute(adopt_id);
}

You can sort list by a property using the following code:
Collections.sort(myList, new MyComparator());
public static class MyComparator implements Comparator<MyData > {
#Override
public int compare(final MyData o1, final MyData o2) {
return o1.getAdoptRownum().compareTo(o2.getAdoptRownum());
}
}
I usually declare comparators inside the relevant POJO class. Then you can call Collections.sort whenever you refresh your data.

Not able to display the listView in android while getting the JSON data

This is my MainActivity.java :
package example.com.getdata;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import org.json.JSONObject;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
public static final String JSON_URL = "http://172.31.131.52:8081/application/status";
private Button buttonGet;
private ListView listView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
buttonGet = (Button) findViewById(R.id.button2);
}
private void sendRequest(){
StringRequest stringRequest = new StringRequest(JSON_URL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
showJSON(response);
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(MainActivity.this,error.getMessage(),Toast.LENGTH_LONG).show();
}
});
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
private void showJSON(String json) {
Product product = new Product(json);
ArrayList<JSONObject> listItems= product.parseJSON();
listView = (ListView) findViewById(R.id.list_view);
CustomList customerList = new CustomList(this,R.layout.list_view_layout,R.id.textViewName, listItems);
//customerList.notifyDataSetChanged();
listView.setAdapter(customerList);
}
public void clickHere(View v) {
sendRequest();
}
}
Product.java
package example.com.getdata;
import android.util.Log;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import static com.android.volley.VolleyLog.TAG;
public class Product {
public String productName;
public String description;
public int priceInDollars;
//public int productID;
public static final String KEY_Name = "productName";
public static final String KEY_Desc = "description";
//public static final String KEY_ID= "ProductID";
public static final String KEY_Price ="priceInDollars" ;
private JSONArray users = null;
private String json;
public Product(String json){
this.json =json;
}
protected ArrayList<JSONObject> parseJSON(){
JSONArray jsonArray=null;
ArrayList<JSONObject> aList=new ArrayList<JSONObject>();
try {
jsonArray = new JSONArray(json);
Log.d("Debugging...", jsonArray.toString());
if(jsonArray != null) {
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jo = jsonArray.getJSONObject(i);
productName = jo.getString(KEY_Name);
description = jo.getString(KEY_Desc);
priceInDollars = jo.getInt(KEY_Price);
aList.add(jsonArray.getJSONObject(i));
// productID = jo.getInt(KEY_ID);
}
return aList;
}
else {
Log.d(TAG, "parseJSON: Null condition");
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
}
CustomList.java
package example.com.getdata;
import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
public class CustomList extends ArrayAdapter<String> {
private ArrayList<JSONObject> list;
private int vg;
private Activity context;
public CustomList(Activity context,int vg, int id, ArrayList<JSONObject> list ) {
super(context,R.layout.list_view_layout, id);
this.vg = vg;
this.context = context;
this.list=list;
// this.productID=productID;
}
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View listViewItem = inflater.inflate(vg, parent, false);
TextView textViewName = (TextView) listViewItem.findViewById(R.id.textViewName);
TextView textViewDescription = (TextView) listViewItem.findViewById(R.id.textViewDescription);
TextView textViewPrice = (TextView) listViewItem.findViewById(R.id.textViewPrice);
// TextView textViewID = (TextView) listViewItem.findViewById(R.id.textViewID);
try {
textViewName.setText(list.get(position).getString("productName"));
textViewDescription.setText(list.get(position).getString("description"));
textViewPrice.setText(list.get(position).getString("priceInDollars"));
}
catch (JSONException e) {
e.printStackTrace();
}
// textViewID.setText(productID);
return listViewItem;
}
}
I have tried and searched for answers online and I am still not able to figure out the problem. I am unable to see the list of objects. Through debugging, I am sure that the objects are read into the json objects, still I am not able to display the objects in a listView.
Any help is appreciated.

You need to crate constructor with all variables of Product class and put all values in Product class object and add into ArrayList .
See Product Class :
public class Product {
public String productName;
public String description;
public int priceInDollars;
//public int productID;
public static final String KEY_Name = "productName";
public static final String KEY_Desc = "description";
//public static final String KEY_ID= "ProductID";
public static final String KEY_Price ="priceInDollars" ;
private JSONArray users = null;
private String json;
public Product(String productName, String json, JSONArray users, int priceInDollars, String description) {
this.productName = productName;
this.json = json;
this.users = users;
this.priceInDollars = priceInDollars;
this.description = description;
}
public String getProductName() {
return productName;
}
public void setProductName(String productName) {
this.productName = productName;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public static String getKEY_Name() {
return KEY_Name;
}
public static String getKEY_Price() {
return KEY_Price;
}
public String getJson() {
return json;
}
public void setJson(String json) {
this.json = json;
}
public JSONArray getUsers() {
return users;
}
public void setUsers(JSONArray users) {
this.users = users;
}
public static String getKEY_Desc() {
return KEY_Desc;
}
public int getPriceInDollars() {
return priceInDollars;
}
public void setPriceInDollars(int priceInDollars) {
this.priceInDollars = priceInDollars;
}
}
And When your are parsing your data you need to change like below code:
protected ArrayList<Product> parseJSON(){
JSONArray jsonArray=null;
ArrayList<Product> aList=new ArrayList<Product>();
try {
jsonArray = new JSONArray(json);
Log.d("Debugging...", jsonArray.toString());
if(jsonArray != null) {
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jo = jsonArray.getJSONObject(i);
String productName = jo.optString(KEY_Name);
String description = jo.optString(KEY_Desc);
String priceInDollars = jo.optInt(KEY_Price);
Product product = new Product(productName,json,
jsonArray.getJSONObject(i),priceInDollars,description);
aList.add(product);
// productID = jo.getInt(KEY_ID);
}
return aList;
}
else {
Log.d(TAG, "parseJSON: Null condition");
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
Also you need to change in Adapter class where you have passes ArrayList<JsonArray> in this case you have to pass ArrayList<Product>.

You missed
#override
public int getCount()
{
return list.size();
}
and make sure you either "setAdapter" on your listview after getting the json or call "notifydatasetchanged" method

Use
super(context,R.layout.list_view_layout, list);
instead of
super(context,R.layout.list_view_layout, id);

Make sure getCount() is properly implemented in Adapterclass:
#Override
public int getCount(){
return list.size();
}

Extend the CustomList class as:
type JSONObject
instead of
type String

How to populate ListView with SQLite database info with next button click

I am building an app that populates a ListView with a single random record from a SQLite DB every time I click on a "next" button for a guessing-style game. Currently I am able to pull a random record from the DB when the app opens, however, I do not know if I need a new class and I do not know where to put the code for the "next" button, nor do I know what the code should be. I'm basically trying to get the app to refresh the ListView with a new single random record from the DB every time someone clicks on a button that says "next". I already have the xml layout done and the app opens and displays the first random record perfectly. Thank you for any help! :)
MainActivity class:
package com.example.derek.guessinggame;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.view.Menu;
import android.view.MenuInflater;
public class MainActivity extends FragmentActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
FragmentManager fragmentManager = getSupportFragmentManager();
if (fragmentManager.findFragmentById(android.R.id.content) == null) {
GuessListFragment guessListFragment = new GuessListFragment();
fragmentManager.beginTransaction().add(android.R.id.content, guessListFragment).commit();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu_main, menu);
return super.onCreateOptionsMenu(menu);
}
ContentProvider class:
package com.example.derek.guessinggame;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteQueryBuilder;
import android.net.Uri;
import android.provider.BaseColumns;
import android.text.TextUtils;
import android.util.Log;
public class GuessProvider extends ContentProvider {
private GuessDatabase mOpenHelper;
private static final String TAG = GuessProvider.class.getSimpleName();
private static final UriMatcher sUriMatcher = buildUriMatcher();
private static final int GUESS = 100;
private static final int GUESS_ID = 101;
private Uri uri;
private String selection;
private String[] selectionArgs;
private static UriMatcher buildUriMatcher() {
final UriMatcher matcher = new UriMatcher(UriMatcher.NO_MATCH);
final String authority = GuessContract.CONTENT_AUTHORITY;
matcher.addURI(authority, "guess", GUESS);
matcher.addURI(authority, "guess/*", GUESS_ID);
return matcher;
}
#Override
public boolean onCreate() {
mOpenHelper = new GuessDatabase(getContext());
return true;
}
private void deleteDatabase() {
mOpenHelper.close();
GuessDatabase.deleteDatabase(getContext());
mOpenHelper = new GuessDatabase(getContext());
}
#Override
public String getType(Uri uri) {
final int match = sUriMatcher.match(uri);
switch (match) {
case GUESS:
return GuessContract.Guess.CONTENT_TYPE;
case GUESS_ID:
return GuessContract.Guess.CONTENT_ITEM_TYPE;
default:
throw new IllegalArgumentException("Unknown Uri: " + uri);
}
}
#Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
final SQLiteDatabase db = mOpenHelper.getReadableDatabase();
final int match = sUriMatcher.match(uri);
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
queryBuilder.setTables(GuessDatabase.Tables.GUESS);
switch (match) {
case GUESS:
// do nothing
break;
case GUESS_ID:
String id = GuessContract.Guess.getGuessId(uri);
queryBuilder.appendWhere(BaseColumns._ID + "=" + id);
break;
default:
throw new IllegalArgumentException("Unknown Uri: " + uri);
}
Cursor cursor = queryBuilder.query(db, projection, selection, selectionArgs, null, null, sortOrder);
return cursor;
}
#Override
public Uri insert(Uri uri, ContentValues values) {
Log.v(TAG, "insert(uri=" + uri + ", values=" + values.toString());
final SQLiteDatabase db = mOpenHelper.getWritableDatabase();
final int match = sUriMatcher.match(uri);
switch (match) {
case GUESS:
long recordId = db.insertOrThrow(GuessDatabase.Tables.GUESS, null, values);
return GuessContract.Guess.buildGuessUri(String.valueOf(recordId));
default:
throw new IllegalArgumentException("Unknown Uri: " + uri);
}
}
#Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
Log.v(TAG, "update(uri=" + uri + ", values=" + values.toString());
final SQLiteDatabase db = mOpenHelper.getWritableDatabase();
final int match = sUriMatcher.match(uri);
String selectionCriteria = selection;
switch (match) {
case GUESS:
// do nothing
break;
case GUESS_ID:
String id = GuessContract.Guess.getGuessId(uri);
selectionCriteria = BaseColumns._ID + "=" + id
+ (!TextUtils.isEmpty(selection) ? " AND (" + selection + ")" : "");
break;
default:
throw new IllegalArgumentException("Unknown Uri: " + uri);
}
return db.update(GuessDatabase.Tables.GUESS, values, selectionCriteria, selectionArgs);
}
#Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
Log.v(TAG, "delete(uri=" + uri);
if (uri.equals(GuessContract.BASE_CONTENT_URI)) {
deleteDatabase();
return 0;
}
final SQLiteDatabase db = mOpenHelper.getWritableDatabase();
final int match = sUriMatcher.match(uri);
switch (match) {
case GUESS_ID:
String id = GuessContract.Guess.getGuessId(uri);
String selectionCriteria = BaseColumns._ID + "=" + id
+ (!TextUtils.isEmpty(selection) ? " AND (" + selection + ")" : "");
return db.delete(GuessDatabase.Tables.GUESS, selectionCriteria, selectionArgs);
default:
throw new IllegalArgumentException("Unknown Uri: " + uri);
}
}
}
ListLoader class:
package com.example.derek.guessinggame;
import android.content.ContentResolver;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.provider.BaseColumns;
import android.support.v4.content.AsyncTaskLoader;
import android.util.Log;
import java.util.ArrayList;
import java.util.List;
public class GuessListLoader extends AsyncTaskLoader<List<Guess>> {
private static final String LOG_TAG = GuessListLoader.class.getSimpleName();
private List<Guess> mGuess;
private ContentResolver mContentResolver;
private Cursor mCursor;
public GuessListLoader(Context context, Uri uri, ContentResolver contentResolver) {
super(context);
mContentResolver = contentResolver;
}
#Override
public List<Guess> loadInBackground() {
String[] projection = {BaseColumns._ID,
GuessContract.GuessColumns.GUESS_TITLE,
GuessContract.GuessColumns.GUESS_ANSWER,
GuessContract.GuessColumns.GUESS_HINT1,
GuessContract.GuessColumns.GUESS_HINT2,
GuessContract.GuessColumns.GUESS_HINT3,
GuessContract.GuessColumns.GUESS_HINT4,
GuessContract.GuessColumns.GUESS_HINT5};
List<Guess> entries = new ArrayList<Guess>();
mCursor = mContentResolver.query(GuessContract.URI_TABLE, projection, null, null, " random()");
if (mCursor != null) {
if (mCursor.moveToFirst()) {
do {
int _id = mCursor.getInt(mCursor.getColumnIndex(BaseColumns._ID));
String title = mCursor.getString(mCursor.getColumnIndex(GuessContract.GuessColumns.GUESS_TITLE));
String answer = mCursor.getString(mCursor.getColumnIndex(GuessContract.GuessColumns.GUESS_ANSWER));
String hint1 = mCursor.getString(mCursor.getColumnIndex(GuessContract.GuessColumns.GUESS_HINT1));
String hint2 = mCursor.getString(mCursor.getColumnIndex(GuessContract.GuessColumns.GUESS_HINT2));
String hint3 = mCursor.getString(mCursor.getColumnIndex(GuessContract.GuessColumns.GUESS_HINT3));
String hint4 = mCursor.getString(mCursor.getColumnIndex(GuessContract.GuessColumns.GUESS_HINT4));
String hint5 = mCursor.getString(mCursor.getColumnIndex(GuessContract.GuessColumns.GUESS_HINT5));
Guess guess = new Guess(_id, title, answer, hint1, hint2, hint3, hint4, hint5);
entries.add(guess);
} while (mCursor.isLast());
}
}
return entries;
}
#Override
public void deliverResult(List<Guess> guess) {
if (isReset()) {
if (guess != null) {
mCursor.close();
}
}
List<Guess> oldGuessList = mGuess;
if (mGuess == null || mGuess.size() == 0) {
Log.d(LOG_TAG, "++++++++ No data returned");
}
mGuess = guess;
if (isStarted()) {
super.deliverResult(guess);
}
if (oldGuessList != null && oldGuessList != guess) {
mCursor.close();
}
}
#Override
protected void onStartLoading() {
if (mGuess != null) {
deliverResult(mGuess);
}
if (takeContentChanged() || mGuess == null) {
forceLoad();
}
}
#Override
protected void onStopLoading() {
cancelLoad();
}
#Override
protected void onReset() {
onStopLoading();
if (mCursor != null) {
mCursor.close();
}
mGuess = null;
}
#Override
public void onCanceled(List<Guess> guess) {
super.onCanceled(guess);
if (mCursor != null) {
mCursor.close();
}
}
#Override
public void forceLoad() {
super.forceLoad();
}
}
ListFragment class:
package com.example.derek.guessinggame;
import android.content.ContentResolver;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.Loader;
import java.util.List;
public class GuessListFragment extends ListFragment
implements LoaderManager.LoaderCallbacks<List<Guess>> {
private static final String LOG_TAG = GuessListFragment.class.getSimpleName();
private GuessCustomAdapter mAdapter;
private static final int LOADER_ID = 1;
private ContentResolver mContentResolver;
private List<Guess> mGuess;
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
setHasOptionsMenu(true);
mContentResolver = getActivity().getContentResolver();
mAdapter = new GuessCustomAdapter(getActivity(), getChildFragmentManager());
setEmptyText("No entries");
setListAdapter(mAdapter);
setListShown(false);
getLoaderManager().initLoader(LOADER_ID, null, this);
}
#Override
public Loader<List<Guess>> onCreateLoader(int id, Bundle args) {
mContentResolver = getActivity().getContentResolver();
return new GuessListLoader(getActivity(), GuessContract.URI_TABLE, mContentResolver);
}
#Override
public void onLoadFinished(Loader<List<Guess>> loader, List<Guess> guess) {
mAdapter.setData(guess);
mGuess = guess;
if(isResumed()) {
setListShown(true);
} else {
setListShownNoAnimation(true);
}
}
#Override
public void onLoaderReset(Loader<List<Guess>> loader) {
mAdapter.setData(null);
}
}
SQLiteOpenHelper class:
package com.example.derek.guessinggame;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.provider.BaseColumns;
public class GuessDatabase extends SQLiteOpenHelper {
private static final String TAG = GuessDatabase.class.getSimpleName();
private static final String DATABASE_NAME = "guess.db";
private static final int DATABASE_VERSION = 2;
private final Context mContext;
interface Tables {
String GUESS = "guess";
}
public GuessDatabase(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
mContext = context;
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + Tables.GUESS + " ("
+ BaseColumns._ID + " INTEGER PRIMARY KEY AUTOINCREMENT,"
+ GuessContract.GuessColumns.GUESS_TITLE + " TEXT NOT NULL,"
+ GuessContract.GuessColumns.GUESS_ANSWER + " TEXT NOT NULL,"
+ GuessContract.GuessColumns.GUESS_HINT1 + " TEXT NOT NULL,"
+ GuessContract.GuessColumns.GUESS_HINT2 + " TEXT NOT NULL,"
+ GuessContract.GuessColumns.GUESS_HINT3 + " TEXT NOT NULL,"
+ GuessContract.GuessColumns.GUESS_HINT4 + " TEXT NOT NULL,"
+ GuessContract.GuessColumns.GUESS_HINT5 + " TEXT NOT NULL)");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
int version = oldVersion;
if (version == 1) {
version = 2;
}
if (version != DATABASE_VERSION) {
db.execSQL("DROP TABLE IF EXISTS " + Tables.GUESS);
onCreate(db);
}
}
public static void deleteDatabase(Context context) {
context.deleteDatabase(DATABASE_NAME);
}
}
ArrayAdapter class:
package com.example.derek.guessinggame;
import android.content.Context;
import android.support.v4.app.FragmentManager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import java.util.List;
public class GuessCustomAdapter extends ArrayAdapter<Guess> {
private LayoutInflater mLayoutInflater;
private static FragmentManager sFragmentManager;
public GuessCustomAdapter(Context context, FragmentManager fragmentManager) {
super(context, android.R.layout.simple_expandable_list_item_2);
mLayoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
sFragmentManager = fragmentManager;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final View view;
if (convertView == null) {
view = mLayoutInflater.inflate(R.layout.custom_guess, parent, false);
} else {
view = convertView;
}
final Guess guess = getItem(position);
final int _id = guess.getId();
final String title = guess.getTitle();
final String answer = guess.getAnswer();
final String hint1 = guess.getHint1();
final String hint2 = guess.getHint2();
final String hint3 = guess.getHint3();
final String hint4 = guess.getHint4();
final String hint5 = guess.getHint5();
((TextView) view.findViewById(R.id.guess_title)).setText(title);
((TextView) view.findViewById(R.id.guess_answer)).setText(answer);
((TextView) view.findViewById(R.id.guess_hint1)).setText(hint1);
((TextView) view.findViewById(R.id.guess_hint2)).setText(hint2);
((TextView) view.findViewById(R.id.guess_hint3)).setText(hint3);
((TextView) view.findViewById(R.id.guess_hint4)).setText(hint4);
((TextView) view.findViewById(R.id.guess_hint5)).setText(hint5);
return view;
}
public void setData(List<Guess> guesses) {
clear();
if (guesses != null) {
for (Guess guess : guesses) {
add(guess);
}
}
}
}
Contract class:
package com.example.derek.guessinggame;
import android.net.Uri;
import android.provider.BaseColumns;
public class GuessContract {
interface GuessColumns{
String GUESS_ID = "_id";
String GUESS_TITLE = "guess_title";
String GUESS_ANSWER = "guess_answer";
String GUESS_HINT1 = "guess_hint1";
String GUESS_HINT2 = "guess_hint2";
String GUESS_HINT3 = "guess_hint3";
String GUESS_HINT4 = "guess_hint4";
String GUESS_HINT5 = "guess_hint5";
}
public static final String CONTENT_AUTHORITY = "com.example.derek.guessinggame.provider";
public static final Uri BASE_CONTENT_URI = Uri.parse("content://" + CONTENT_AUTHORITY);
private static final String PATH_GUESS = "guess";
public static final Uri URI_TABLE = Uri.parse(BASE_CONTENT_URI.toString() + "/" + PATH_GUESS);
public static final String[] TOP_LEVEL_PATHS = {
PATH_GUESS
};
public static class Guess implements GuessColumns, BaseColumns {
public static final Uri CONTENT_URI =
BASE_CONTENT_URI.buildUpon().appendEncodedPath(PATH_GUESS).build();
public static final String CONTENT_TYPE = "vnd.android.cursor.dir/vnd." + CONTENT_AUTHORITY + ".guess";
public static final String CONTENT_ITEM_TYPE = "vnd.android.cursor.item/vnd." + CONTENT_AUTHORITY + ".guess";
public static Uri buildGuessUri(String guessId) {
return CONTENT_URI.buildUpon().appendEncodedPath(guessId).build();
}
public static String getGuessId(Uri uri) {
return uri.getPathSegments().get(1);
}
}
}
Getters and Setter class:
package com.example.derek.guessinggame;
public class Guess {
private int _id;
private String title;
private String answer;
private String hint1;
private String hint2;
private String hint3;
private String hint4;
private String hint5;
public Guess(int _id, String title, String answer, String hint1, String hint2, String hint3, String hint4, String hint5) {
this._id = _id;
this.title = title;
this.answer = answer;
this.hint1 = hint1;
this.hint2 = hint2;
this.hint3 = hint3;
this.hint4 = hint4;
this.hint5 = hint5;
}
public int getId() {
return _id;
}
public void setId(int _id) {
this._id = _id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getAnswer() {
return answer;
}
public void setAnswer(String answer) {
this.answer = answer;
}
public String getHint1() {
return hint1;
}
public void setHint1(String hint1) {
this.hint1 = hint1;
}
public String getHint2() {
return hint2;
}
public void setHint2(String hint2) {
this.hint2 = hint2;
}
public String getHint3() {
return hint3;
}
public void setHint3(String hint3) {
this.hint3 = hint3;
}
public String getHint4() {
return hint4;
}
public void setHint4(String hint4) {
this.hint4 = hint4;
}
public String getHint5() {
return hint5;
}
public void setHint5(String hint5) {
this.hint5 = hint5;
}
}