Develop Reference

How to add a search filter in RecyclerView to filter through parsed JSON data? edited

I am developing an android app which shows a list of countries affected by Coronavirus , the total number of confirmed cases and total Deaths. I am using a JSON API to get the data and displaying it using a RecyclerView . The app works fine , and i get a list of all the countries with their respective case counts. I want to add a search option so that the users can filter the list and find a specific country. How do i do that? I am new to programming , if someone could help with this that would be awesome.
Here is the code snippet
MainActivity.java
private RecyclerView mRecyclerView;
private Corona_Stats_Adapter mCorona_Stats_Adapter;
private TextView mErrorDisplay;
private ProgressBar mProgressBar;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.corona_stats);
mRecyclerView = (RecyclerView)findViewById(R.id.Corona_stats_recycler);
mErrorDisplay = (TextView) findViewById(R.id.tv_error_message_display);
LinearLayoutManager layoutManager = new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false);
mRecyclerView.setLayoutManager(layoutManager);
mRecyclerView.setHasFixedSize(true);
mCorona_Stats_Adapter = new Corona_Stats_Adapter();
mRecyclerView.setAdapter(mCorona_Stats_Adapter);
mProgressBar = (ProgressBar)findViewById(R.id.pb_loading_indicator) ;
loadCoronaData();
}
private void loadCoronaData(){
showCoronaDataView();
//String Country = String.valueOf(mSearchQuery.getText());
new Fetch_data().execute();
}
private void showCoronaDataView(){
mErrorDisplay.setVisibility(View.INVISIBLE);
mRecyclerView.setVisibility(View.VISIBLE);
}
private void showErrorMessage(){
mRecyclerView.setVisibility(View.INVISIBLE);
mErrorDisplay.setVisibility(View.VISIBLE);
}
public class Fetch_data extends AsyncTask<Void,Void,String[]> {
#Override
protected void onPreExecute() {
super.onPreExecute();
mProgressBar.setVisibility(View.VISIBLE);
}
#Override
protected String[] doInBackground(Void... voids) {
URL covidRequestURL = NetworkUtils.buildUrl();
try {
String JSONCovidResponse = NetworkUtils.getResponseFromHttpUrl(covidRequestURL);
String[] simpleJsonCovidData = CovidJSON_Utils.getSimpleStringFromJson(MainActivity.this, JSONCovidResponse);
return simpleJsonCovidData;
} catch (IOException | JSONException e) {
e.printStackTrace();
return null;
}
}
#Override
protected void onPostExecute(String[] coronaData) {
mProgressBar.setVisibility(View.INVISIBLE);
if(coronaData !=null){
showCoronaDataView();
mCorona_Stats_Adapter.setCoronaData(coronaData);
} else{
showErrorMessage();
}
}
}
}
RecyclerView Adapter class Corona_stats_Adapter.java
public class Corona_Stats_Adapter extends RecyclerView.Adapter<Corona_Stats_Adapter.Corona_Stats_AdapterViewHolder>
{
private Context context;
// private List<Country> countryList;
// private List<Country> countryListFiltered;
private String[] mCoronaData;
public Corona_Stats_Adapter(){
}
#NonNull
#Override
public Corona_Stats_AdapterViewHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int viewType) {
Context context = viewGroup.getContext();
int LayoutIdForListItem =R.layout.corona_stats_list_item;
LayoutInflater inflater =LayoutInflater.from(context);
boolean ShouldAttachToParentImmediately = false;
View view = inflater.inflate(LayoutIdForListItem,viewGroup,ShouldAttachToParentImmediately);
return new Corona_Stats_AdapterViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull Corona_Stats_AdapterViewHolder corona_stats_adapterViewHolder, int position) {
String coronaStats = mCoronaData[position];
corona_stats_adapterViewHolder.mCoronaTextView.setText(coronaStats);
}
#Override
public int getItemCount() {
if(null == mCoronaData) return 0;
return mCoronaData.length;
// return countryListFiltered.size();
}
public class Corona_Stats_AdapterViewHolder extends RecyclerView.ViewHolder {
public final TextView mCoronaTextView;
public Corona_Stats_AdapterViewHolder(#NonNull View view) {
super(view);
mCoronaTextView = (TextView) view.findViewById(R.id.tv_corona_data);
}
}
public void setCoronaData(String[] coronaData){
mCoronaData = coronaData;
notifyDataSetChanged();
}
}
Parsing the JSON data in CovidJSON_Utils.java
public final class CovidJSON_Utils {
public static String[] getSimpleStringFromJson(Context context, String codivJsonString)
throws JSONException {
final String COV_COUNTRY = "Countries";
final String COV_CONFIRMED = "confirmed";
final String COV_DEATHS = "deaths";
final String COV_MESSAGE_CODE = "code";
String[] parsedCovidData = null;
JSONObject covidJsonObject = new JSONObject(codivJsonString);
if (covidJsonObject.has(COV_MESSAGE_CODE)) {
int errorCode = covidJsonObject.getInt(COV_MESSAGE_CODE);
switch (errorCode) {
case HttpURLConnection.HTTP_OK:
break;
case HttpURLConnection.HTTP_NOT_FOUND:
return null;
default:
return null;
}
}
JSONArray countryCovidArray = covidJsonObject.getJSONArray(COV_COUNTRY);
parsedCovidData = new String[countryCovidArray.length()];
for (int i = 0; i < countryCovidArray.length(); i++) {
JSONObject countryJSONObject = countryCovidArray.getJSONObject(i);
String Country = countryJSONObject.getString("Country");
String Confirmed = String.valueOf(countryJSONObject.getInt("TotalConfirmed"));
String Deaths = String.valueOf(countryJSONObject.getInt("TotalDeaths"));
parsedCovidData[i] = Country + "- Cases " + Confirmed + "- Deaths " + Deaths;
}
return parsedCovidData;
}
}

The problem is with below initialization in the MainActivity.Oncreate method
mCorona_Stats_Adapter = new Corona_Stats_Adapter(this,countries);
Initialize the adapter in onPostExecute method with updated countries data.
Hope this will help you.

You have to set arraylist to update country data in adapter after getting data from the server.
Public void setCoronaData (Arraylist coronaData) {
countryList = coronaData;
notifyDataSetChanged ();
}

How to Delete Item Without Deleting Position in Recycler View?

I really need your help. I've searched Google many days with many keywords, but I couldn't get it. So, I decided to ask to you.
So, here it is. Actually, I have one button in RecyclerView, but this button is repeated as much amount of data available, there are: Button with text "Baca 3x", "Baca 4x", and so on. I want, if I click button with text "Baca 3x" 3 times, it will change to "Baca 2x" >> "Baca 1x" >> remove item. Also if I click button with text "Baca 4x" 4 times, it will change to "Baca 3x" >> "Baca 2x" >> "Baca 1x" >> remove item.
But my problem is, I can't treat every button with different treatment, because every time the item has been deleted, position of data changes automatically. Because of this, I can't get specific button. For example: There is two button,
1. Button "Baca 3x" on position 0
2. Button "Baca 4x" on position 1
If button "Baca 3x" on position 0 has been deleted, so button "Baca 4x" changed it's position automatically to 0. The problem lays here.
Until now I just get every button based on their positions, which is a problem for me. Because of this I am thinking about How to Delete Item Without Deleting Position in Recycler View? Can you guys solve my problem? Should I use DiffUtil?And how to use it? Below the complete code I use:
ModelDoa.java
public class ModelDoa {
public static final int DOA_PAGI = 0;
public static final int DOA_SORE = 1;
public static final int DOA_MASJID = 2;
public static final int DOA_BANGUNT = 3;
public static final int DOA_MAU_TIDUR = 4;
private String mName;
private String bName;
private int mType;
public ModelDoa(String name, String butong, int type) {
this.mName = name;
this.bName = butong;
this.mType = type;
}
public String getName() {
return mName;
}
public void setName(String name) {
this.mName = name;
}
public int getType() {
return mType;
}
public void setType(int type) { this.mType = type; }
public String ambilName() {
return bName;
}
public void setNama(String butonk) {
this.bName = butonk;
}
}
AdapterDoa.java
public class AdapterDoa extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
public List<ModelDoa> mList;
public AdapterDoa(List<ModelDoa> list) {
this.mList = list;
}
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
switch (viewType) {
case DOA_PAGI:
View vieu = LayoutInflater.from(parent.getContext()).inflate(R.layout.content_doa, parent, false);
PagiViewHolder rcv = new PagiViewHolder(vieu, this);
return rcv;
case DOA_SORE:
View doa = LayoutInflater.from(parent.getContext()).inflate(R.layout.content_doa, parent, false);
SoreViewHolder mdoa = new SoreViewHolder(doa);
return mdoa;
case DOA_MASJID:
View dMasjid = LayoutInflater.from(parent.getContext()).inflate(R.layout.content_doa, parent, false);
MasjidViewHolder mMasjid = new MasjidViewHolder(dMasjid);
return mMasjid;
case DOA_BANGUNT:
View dBangunt = LayoutInflater.from(parent.getContext()).inflate(R.layout.content_doa, parent, false);
BanguntViewHolder mBangunt = new BanguntViewHolder(dBangunt);
return mBangunt;
case DOA_MAU_TIDUR:
View regut = LayoutInflater.from(parent.getContext()).inflate(R.layout.content_doa, parent, false);
MauTidurViewHolder turu = new MauTidurViewHolder(regut);
return turu;
}
return null;
}
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
ModelDoa object = mList.get(position);
if (object != null) {
switch (object.getType()) {
case DOA_PAGI:
((PagiViewHolder) holder).mTitle.setText(object.getName());
((PagiViewHolder) holder).tombolbaca.setText(object.ambilName());
break;
case DOA_SORE:
((SoreViewHolder) holder).mTitle.setText(object.getName());
((SoreViewHolder) holder).tombolbaca.setText(object.ambilName());
break;
case DOA_MASJID:
((MasjidViewHolder) holder).mTitle.setText(object.getName());
((MasjidViewHolder) holder).tombolbaca.setText(object.ambilName());
break;
case DOA_BANGUNT:
((BanguntViewHolder) holder).mTitle.setText(object.getName());
((BanguntViewHolder) holder).tombolbaca.setText(object.ambilName());
break;
case DOA_MAU_TIDUR:
((MauTidurViewHolder) holder).mTitle.setText(object.getName());
((MauTidurViewHolder) holder).tombolbaca.setText(object.ambilName());
break;
}
}
}
public void deleteItem(int position) {
mList.remove(position); // hapus list
notifyItemRemoved(position); // hapus tampilan
// notifyItemRangeChanged( position, mList.size());
}
#Override
public int getItemCount() {
if (mList == null)
return 0;
return mList.size();
}
#Override
public int getItemViewType(int position) {
if (mList != null) {
ModelDoa object = mList.get(position);
if (object != null) {
return object.getType();
}
}
return 0;
}
}
PagiViewHolder.java
public class PagiViewHolder extends RecyclerView.ViewHolder {
public TextView mTitle;
public Button tombolbaca;
public Button teksbaca;
public Button tombolshare;
private RelativeLayout rl2;
private int klik10 = 10;
private AdapterDoa myAdapter;
public PagiViewHolder(View itemView, AdapterDoa myAdapter) {
super(itemView);
this.myAdapter = myAdapter;
itemView.setOnClickListener(mainViewClickListener);
mTitle = (TextView) itemView.findViewById(R.id.titleTextView);
tombolbaca = (Button) itemView.findViewById(R.id.buttonbaca);
tombolshare = (Button) itemView.findViewById(R.id.buttonshare);
tombolbaca.setOnClickListener(bacaClickListener);
tombolshare.setOnClickListener(shareClickListener);
rl2 = (RelativeLayout) itemView.findViewById(R.id.relmasjid);
}
private View.OnClickListener bacaClickListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
teksbaca = (Button) v.findViewById(R.id.buttonbaca);
// Baca 10x
if( getAdapterPosition() ==0 ) {
klik10--;
teksbaca.setText("Baca " + klik10 + "x");
if (klik10 <= 0)
{
// modify listItems however you want... add, delete, shuffle, etc
myAdapter.deleteItem(getAdapterPosition());
}
}
} // onclick
};
private View.OnClickListener shareClickListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
// Do button click handling here
Intent sendIntent = new Intent();
sendIntent.setAction(Intent.ACTION_SEND);
sendIntent.putExtra(Intent.EXTRA_TEXT, mTitle.getText().toString() + "\n \n download aplikasinya di: http://www.tauhid.or.id" );
sendIntent.setType("text/plain");
Intent.createChooser(sendIntent,"Share via");
v.getContext().startActivity(sendIntent);
}
};
private View.OnClickListener mainViewClickListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
// Do button click handling here
}
};
}
DoaPagi.java
public class DoaPagi extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_doa_pagi);
// toolbar
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
//this line shows back button
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
List<ModelDoa> rowListItem = getData();
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(DoaPagi.this);
RecyclerView mRecyclerView = (RecyclerView) findViewById(R.id.recyclerView);
mRecyclerView.setLayoutManager(linearLayoutManager);
mRecyclerView.setHasFixedSize(true);
AdapterDoa rcAdapter = new AdapterDoa(rowListItem);
mRecyclerView.setAdapter(rcAdapter);
}
private List<ModelDoa> getData() {
String[] data = getResources().getStringArray(R.array.doapagi);
String[] baca = getResources().getStringArray(R.array.bacapagi);
List<ModelDoa> list = new ArrayList<ModelDoa>();
for (int i = 0; i < data.length; i++) {
list.add(new ModelDoa(data[i], baca[i], ModelDoa.DOA_PAGI));
}
return list;
}
// Agar back button pada halaman induk settings berfungsi
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
this.finish();
return true;
}
return super.onOptionsItemSelected(item);
}
}
UPDATE (FIX CODE) By: Krishna Sharma:
https://github.com/seadclark/RecyclerViewWithButtonClicks

Here is the fix. just update the ModelDoa constructor as below. I have verified myself and working as expected now. Also sent you pull request on github.
public ModelDoa(String name, String butong, int type) {
this.mName = name;
this.bName = butong;
this.mType = type;
String[] data = butong.split("\\s");
if (data.length > 0) {
String count = data[1].substring(0, data[1].length() - 1);
read10 = Integer.parseInt(count);
}
}

Instead of removing the item from your list AND updating the interface, have two methods. One of them (deleteItem) will only delete the item and the other (deleteItemAndUpdate) will delete the item and update the interface.
public void deleteItem(int position) {
mList.remove(position); // hapus list
}
public void deleteItemAndUpdate(int position) {
mList.remove(position); // hapus list
notifyItemRemoved(position); // hapus tampilan
}
In the future, you can decide whether you want to only remove the item from your list OR remove the item and update the UI.
EDIT 1:
You need to keep track of the amount of times that each item was clicked. We can call this value readCount. Every time that the item is clicked, we subtract 1 from this value. When this value reaches 0, we remove it from the list.
ModelDoa:
public class ModelDoa {
private int readCount = 10;
public int getReadCount() {
return this.readCount;
}
public void setReadCount(int readCount) {
this.readCount = readCount;
}
}
PagiViewHolder:
private View.OnClickListener bacaClickListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
teksbaca = (Button) v.findViewById(R.id.buttonbaca);
ModelDoa modelDoa = mAdapter.getItem(getAdapterPosition());
if (modelDoa != null) {
modelDoa.setReadCount(modelDoa.getReadCount() - 1);
if (modelDoa.getReadCount() <= 0) {
myAdapter.deleteItem(getAdapterPosition());
}
teksbaca.setText("Baca " + modelDoa.getReadCount() + "x");
}
}
};
AdapterDoa:
public ModelDoa getItem(int position) {
if (position > -1 && position < getItemCount()) {
return this.mList.get(position);
} else {
return null;
}
}
EDIT 2:
The idea is to set the readCount variable when you instantiate the object. You do not have multiple variables that do the same thing. You just change the single readCount variable to be either 7 or 10 when you are creating it and use the same getItem method when retrieving the model (not variable!) itself.
ModelDoa:
public class ModelDoa {
private String name;
private String butong;
private int type;
private int readCount;
public ModelDoa(String name, String butong, int type, int readCount) {
this.mName = name;
this.bName = butong;
this.mType = type;
this.readCount = readCount;
}
public int getReadCount() {
return this.readCount;
}
public void setReadCount(int readCount) {
this.readCount = readCount;
}
}
DoaPagi:
private List<ModelDoa> getData() {
String[] data = getResources().getStringArray(R.array.doapagi);
String[] baca = getResources().getStringArray(R.array.bacapagi);
List<ModelDoa> list = new ArrayList<ModelDoa>();
for (int i = 0; i < data.length; i++) {
// Here is where you would set the value of readCount.
list.add(new ModelDoa(data[i], baca[i], ModelDoa.DOA_PAGI, i));
}
return list;
}

Android Studio app works when I launch it from Android Studio, but not when I launch from device

I am new to app development and so far my app is working as intended but only when I launch it on my device from Android Studio. For example, I have once instance variable that I give a value of 1 in the onCreate() method. When I launch the app from android studio on to my device, it works fine and the variable has a value of 1. However, when I launch it from my device without using android studio, the variable is given a value of 0. I have also found that I will get a bunch of NullPointerExceptions on variables that I know should have a value, and once again it works when launched from Android Studio, but not when launched from the device.
Here is MainActivity
public class MainActivity extends AppCompatActivity
{
private ArrayList<String> arrayList;
private ArrayList<ListItem> itemList;
private ArrayAdapter<String> adapter;
private EditText txtInput;
private int payRoll;
private String value;
private Intent mainToPayroll;
private int hours;
private int earnings;
private ArrayList<Integer> rollList;
private ArrayList<Integer> hourList;
private ArrayList<Integer> wageList;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
rollList = new ArrayList<>(0);
hourList = new ArrayList<>(0);
wageList = new ArrayList<>(0);
payRoll = 1;
Bundle bun = getIntent().getExtras();
if(bun != null)
{
rollList = bun.getIntegerArrayList("rolls");
hourList = bun.getIntegerArrayList("hours");
wageList = bun.getIntegerArrayList("wages");
payRoll = bun.getInt("roll");
}
ListView listView = (ListView) findViewById(R.id.listv);
String[] items = {};
arrayList = new ArrayList<>(Arrays.asList(items));
itemList = new ArrayList<>(0);
adapter = new ArrayAdapter<String>(this, R.layout.list_item, R.id.txtitem, arrayList);
listView.setAdapter(adapter);
Button btAdd = (Button) findViewById(R.id.btadd);
mainToPayroll = new Intent(this, PayrollActivity.class);
if(rollList != null)
{
for (int i = 0; i < rollList.size(); i++) {
ListItem newItem = new ListItem(rollList.get(i), hourList.get(i), wageList.get(i));
arrayList.add(newItem.toString());
itemList.add(newItem);
adapter.notifyDataSetChanged();
}
rollList.clear();
hourList.clear();
wageList.clear();
}
btAdd.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
ListItem newItem = new ListItem(payRoll, 0, 0);
arrayList.add(newItem.toString());
itemList.add(newItem);
adapter.notifyDataSetChanged();
payRoll++;
}
});
listView.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
value = (String)adapter.getItem(position);
ListItem item = itemList.get(position);
Bundle info = new Bundle();
info.putString("val", value);
info.putInt("hours", item.getHours());
info.putInt("wage", item.getWages());
info.putInt("pos", position);
if(itemList.size() > 0)
{
for (ListItem items : itemList)
{
rollList.add(items.getPayroll());
hourList.add(items.getHours());
wageList.add(items.getWages());
}
}
info.putIntegerArrayList("rolls", rollList);
info.putIntegerArrayList("hours", hourList);
info.putIntegerArrayList("wages", wageList);
info.putInt("roll", payRoll);
info.putBoolean("rest", restore);
mainToPayroll.putExtras(info);
startActivity(mainToPayroll);
}
});
}
This Activity is started whenever an item on the listview is clicked
public class PayrollActivity extends AppCompatActivity
{
private static TextView text;
private String payrollNumber;
private int payrollHrs;
private int payrollWages;
private int position;
private Intent payrollToMain;
private Button returnButton;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_payroll);
final Bundle info = getIntent().getExtras();
System.out.print(getIntent().getType());
payrollNumber = info.getString("val");
payrollHrs = info.getInt("hours");
payrollWages = info.getInt("wage");
position = info.getInt("pos");
payrollToMain = new Intent(this, MainActivity.class);
returnButton = (Button) findViewById(R.id.btnRtrn);
returnButton.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
Bundle thing = new Bundle();
thing.putIntegerArrayList("rolls", info.getIntegerArrayList("rolls"));
thing.putIntegerArrayList("hours", info.getIntegerArrayList("hours"));
thing.putIntegerArrayList("wages", info.getIntegerArrayList("wages"));
thing.putInt("roll", info.getInt("roll"));
thing.putBoolean("rest", info.getBoolean("rest"));
payrollToMain.putExtras(thing);
startActivity(payrollToMain);
}
});
text = (TextView) findViewById(R.id.title);
text.setText(payrollNumber);
}
public static void setLabelText(String val)
{
text.setText(val);
}
This is a class I created for the items that go on the listview
public class ListItem
{
private int payroll;
private int hrs;
private int wages;
public ListItem(int roll, int hours, int wag)
{
payroll = roll;
hrs = hours;
wages = wag;
}
public int getPayroll()
{
return payroll;
}
public int getHours()
{
return hrs;
}
public int getWages()
{
return wages;
}
public void setPayroll(int roll)
{
payroll = roll;
}
public void setHrs(int hours)
{
hrs = hours;
}
public void setWages(int wage)
{
wages = wage;
}
public String toString()
{
return "Payroll " + payroll + "\n" + hrs + " hours\n$" + wages;
}

I think your problem is this piece of code in your MainActivity:
Bundle bun = getIntent().getExtras();
if(bun != null)
{
rollList = bun.getIntegerArrayList("rolls");
hourList = bun.getIntegerArrayList("hours");
wageList = bun.getIntegerArrayList("wages");
payRoll = bun.getInt("roll");
}
The getIntent().getExtras() may return a non-null Bundle object but the bundle may not have the keys you are trying to access, in which case all your instance variables will be set to null or zero for int.
You can get around this by simply checking if a particular key exists in the bundle and only setting your variable if it does.
bun.containsKey()
Or you can initialize your variables if they are null after loading them from the bundle.

Try uninstalling the app completely from the device and then try again. This solves the issue at times.

My Android UI doesn't run?

I implemented AsyncTask to execute results. Here is the error I get...
FATAL EXCEPTION: AsyncTask #1
Process: ai69.psoui, PID: 3287
java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:309)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.<init>(Handler.java:200)
at android.os.Handler.<init>(Handler.java:114)
at android.app.Activity.<init>(Activity.java:754)
at android.support.v4.app.SupportActivity.<init>(SupportActivity.java:31)
at android.support.v4.app.BaseFragmentActivityGingerbread.<init>(BaseFragmentActivityGingerbread.java:37)
at android.support.v4.app.BaseFragmentActivityHoneycomb.<init>(BaseFragmentActivityHoneycomb.java:29)
at android.support.v4.app.BaseFragmentActivityJB.<init>(BaseFragmentActivityJB.java:30)
at android.support.v4.app.FragmentActivity.<init>(FragmentActivity.java:79)
at android.support.v7.app.AppCompatActivity.<init>(AppCompatActivity.java:61)
at ai69.psoui.MainActivity.<init>(MainActivity.java:0)
at android_tests.CustomUseCase.<init>(CustomUseCase.java:19)
at android_tests.TestFactory.getTest(TestFactory.java:15)
at ai69.psoui.ParticleActivity.runTest(ParticleActivity.java:91)
at ai69.psoui.ParticleActivity$runTests.doInBackground(ParticleActivity.java:53)
at ai69.psoui.ParticleActivity$runTests.doInBackground(ParticleActivity.java:50)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
I have looked at different SOF posts about "Looper.prepare()" but the thing is, prior to a few changes in changing static variables to getter/setter methods, my UI was working fine.
Here is my code...
public class ParticleActivity extends AppCompatActivity {
public final static String EXTRA_MESSAGE = "PSOUI.MESSAGE";
private ProgressDialog pd;
private double[] results = {-1.0, -1.0, -1.0};
EditText particles;
EditText iterations;
EditText userSol;
EditText userBatt;
private double battery;
private double solution;
//int numberOfDimensions = MainActivity.dimensions.size();
//public ArrayList<Double> costData = MainActivity.costDATA; //costs that
the user enters for each resource
//public ArrayList<Double> costWlan = MainActivity.costWLAN;
//public ArrayList<Double> costUtilities = MainActivity.costUTILITY;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_particle);
particles = (EditText) findViewById(R.id.particles);
iterations = (EditText) findViewById(R.id.iterations);
userSol = (EditText) findViewById(R.id.solution);
userBatt = (EditText) findViewById(R.id.battery);
pd = null;
runPSOButton();
}
#Override
public void onPause(){
super.onPause();
if(pd != null)
pd.dismiss();
}
public class runTests extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... params) { //sort this out
results = runTest("CustomUseCase"); //i only want to run this one!!!
return null;
}
#Override
protected void onPostExecute(Void v) {
if (results != null && results.length > 0 && results[0] != -1) {
loadIntent(results);
} //otherwise it will evaluate the next logic statement results[0] != -1 with no chance of NulLPointerException
}
#Override
protected void onPreExecute() {
pd = ProgressDialog.show(ParticleActivity.this, "Busy", "Algorithm is currently executing");
pd.setCancelable(true);
pd.show();
}
}
public void runPSOButton() {
final Button runPSO = (Button) findViewById(R.id.runpso);
runPSO.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(final View v) {
new runTests().execute();
}
});
}
public double[] runTest(String test) {
int noPart = Integer.parseInt(particles.getText().toString());
int noIter = Integer.parseInt(iterations.getText().toString());
return new TestFactory(noPart, noIter).getTest(test).test();
}
public void loadIntent(double[] result) {
double[] results = result;
Intent intent = new Intent(this, SolutionActivity.class);
intent.putExtra(EXTRA_MESSAGE, results);
startActivity(intent);
}
public double setBatteryCost(){
battery = Double.parseDouble(userBatt.getText().toString());
return battery;
}
public double getBatteryCost(){return setBatteryCost();}
public double setUserSolution(){
solution = Double.parseDouble(userSol.getText().toString());
return solution;
}
public double getUserSolution(){return setUserSolution();}
}
Can someone explain whats happening? New to Android Studio and have been developing for only 3 months in Java, so for any solutions can I kindly request an explanation for it too? Much appreciated thank you
UPDATE:
Here is my mainActivity...
public class MainActivity extends AppCompatActivity {
//declare variables
EditText name;
EditText data;
EditText wlan;
EditText utility;
Button addservice;
ListView lv;
ListView lv2;
ListView lv3;
ListView lv4;
public ArrayList<String> servicenames;
public ArrayList<String> dimensions;
public ArrayList<Double> costDATA;
public ArrayList<Double> costWLAN;
public ArrayList<Double> costUTILITY;
ArrayAdapter<String> namesAdapter;
ArrayAdapter<Double> dataAdapter;
ArrayAdapter<Double> wlanAdapter;
ArrayAdapter<Double> utilityAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//map the components to the variables
name = (EditText) findViewById(R.id.servicename);
data = (EditText) findViewById(R.id.data);
wlan = (EditText) findViewById(R.id.wlan);
utility = (EditText) findViewById(R.id.utility);
addservice = (Button) findViewById(R.id.addservice);
lv = (ListView) findViewById(R.id.lv);
lv2 = (ListView) findViewById(R.id.lv2);
lv3 = (ListView) findViewById(R.id.lv3);
lv4 = (ListView) findViewById(R.id.lv4);
//create arraylists for each component
servicenames = new ArrayList<String>();
dimensions = new ArrayList<String>();
costDATA = new ArrayList<Double>();
costWLAN = new ArrayList<Double>();
costUTILITY = new ArrayList<Double>();
//create adapters to pass on the arraylist
namesAdapter = new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_list_item_1, servicenames);
dataAdapter = new ArrayAdapter<Double>(MainActivity.this, android.R.layout.simple_list_item_1, costDATA);
wlanAdapter = new ArrayAdapter<Double>(MainActivity.this, android.R.layout.simple_list_item_1, costWLAN);
utilityAdapter = new ArrayAdapter<Double>(MainActivity.this, android.R.layout.simple_list_item_1, costUTILITY);
//display each arraylist in the listviews
lv.setAdapter(namesAdapter);
lv2.setAdapter(wlanAdapter);
lv3.setAdapter(dataAdapter);
lv4.setAdapter(utilityAdapter);
namesAdapter.notifyDataSetChanged();
dataAdapter.notifyDataSetChanged();
wlanAdapter.notifyDataSetChanged();
utilityAdapter.notifyDataSetChanged();
dimensions.add("DATA");
dimensions.add("WLAN");
onClickBtn();
}
public void onClickBtn() { //when user clicks button, the user input is added to the listview, and cleared for the next service
addservice.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String namesOfService = name.getText().toString(); //user input for service names
String costOfData = data.getText().toString(); //user input for data costs
String costOfWLAN = wlan.getText().toString(); //user input for wlan costs
String costOfUtility = utility.getText().toString(); //user input for utility costs
Double doubleWLAN = Double.parseDouble(costOfWLAN); //convert user input into double
Double doubleData = Double.parseDouble(costOfData);
Double doubleUtility = Double.parseDouble(costOfUtility);
costDATA.add(doubleData); //add the double costs to each resource arraylist
costWLAN.add(doubleWLAN);
costUTILITY.add(doubleUtility);
servicenames.add(namesOfService);
dimensions.add(namesOfService);
namesAdapter.notifyDataSetChanged();
dataAdapter.notifyDataSetChanged();
wlanAdapter.notifyDataSetChanged();
utilityAdapter.notifyDataSetChanged();
name.setText(""); //empty the edit text fields when button is clicked
wlan.setText("");
data.setText("");
utility.setText("");
}
});
}
public void nextButton(View view) //next button, onto the next activity
{
Intent intent = new Intent(MainActivity.this, ParticleActivity.class);
startActivity(intent);
}
public int getDimensions(){ return dimensions.size();}
public ArrayList<String> getElements(){ return servicenames;}
public ArrayList<Double> getCostDATA(){;return costDATA;}
public ArrayList<Double> getCostWLAN(){return costUTILITY;}
public ArrayList<Double> getCostUTILITY(){return costUTILITY;}
}
As you can see, the arraylists that store the user input is accessible using getters and setters rather than setting the arraylists static (which I did before). I access these arraylists in another class called CustomUseCase and CustomService. Here is the code for customUseCase:
public class CustomUseCase extends Test {
MainActivity mainActivity = new MainActivity();
ParticleActivity particleActivity = new ParticleActivity();
private int numberOfDimensions = mainActivity.getDimensions();
private ArrayList<Double> costData = mainActivity.getCostDATA(); //costs that the user enters for each resource
private ArrayList<Double> costWlan = mainActivity.getCostWLAN();
private ArrayList<Double> costUtilities = mainActivity.getCostUTILITY();
private double batteryCost = particleActivity.getBatteryCost();
private int maxIter;
private int noParticles;
public CustomUseCase(int noParticles, int maxIterations) {
this.noParticles = noParticles;
this.maxIter = maxIterations;
}
#Override
public double[] test() {
long max = 10000; //maximum number of iterations, override //2 bits for the WLAN/DATA and the rest for the amount of services the user inputs
double[] results = new double[numberOfDimensions]; //new array of results with numOfBits as number of elements
for (int i = 1; i <= max; i++) {
BinaryPso bpso = new BinaryPso(noParticles,
numberOfDimensions);
ParticleActivity getUserInput = new ParticleActivity();
CustomService customService =
new CustomService(batteryCost, costData, costWlan, costUtilities);
long start = System.currentTimeMillis(); //start time
bpso.setSolution(getUserInput.getUserSolution()); //changed this to user selection
bpso.optimize(maxIter, customService, true);
this.found += (bpso.getFound() ? 1 : 0);
this.iterations += bpso.getSolIterations(); //use the method in bpso to get number of iterations taken
long end = System.currentTimeMillis() - start; //end time minus start time
this.sumTimes += end; //override the time spent variable
System.out.println("P-value: " + Particle.getValue(Particle.bestGlobal()));
System.out.println("P-bitCombo: " + Arrays.toString(Particle.bestGlobal()));
System.out.println("P-goodness: " + customService.getGoodness(Particle.bestGlobal()));
}
System.out.println("Time: " + sumTimes / max);
System.out.println("Iterations: " + iterations / max);
System.out.println("Success Rate: " + found);
boolean[] bestCombo = Particle.bestGlobal();
for (Boolean b : bestCombo) {
System.out.print(b + " ");
}
System.out.println();
results[0] = sumTimes / max;
results[1] = iterations / max;
results[2] = found;
return results;
}
public static List<Boolean> getBestComboArray() { //method to get best global array
boolean[] bestCombo = Particle.bestGlobal(); //calculate best global
List<Boolean> bestCombi = new ArrayList<>(bestCombo.length);
for (int x = 0; x < bestCombo.length; x++) {
bestCombi.add(bestCombo[x]);
}
return bestCombi;
}
}
And here is my CustomService class:
public class CustomService implements Goodness {
MainActivity mainActivity = new MainActivity();
private int numOfDimensions = mainActivity.getDimensions();
private ArrayList<String> serviceNames = mainActivity.getElements();
private ArrayList<Double> costData = mainActivity.getCostDATA();
private ArrayList<Double> costWlan = mainActivity.getCostWLAN();
private ArrayList<Double> costUtilities = mainActivity.getCostUTILITY();
private double batteryCost;
public void setBatteryCost(double batteryCost) {
this.batteryCost = batteryCost;
}
public CustomService(double batteryCost, ArrayList<Double> costData, ArrayList<Double> costWlan,
ArrayList<Double> costUtilities) {
if (costUtilities == null || costUtilities.size() < 1 || costData.size() < 1 || costWlan.size() < 1) {
throw new RuntimeException("Please add atleast 1 cost to Data, WLAN and Utility");
}
this.batteryCost = batteryCost; //make sure you add battery field to UI, user enters battery level
this.costData = costData;
this.costWlan = costWlan;
this.costUtilities = costUtilities;
}
public double getGoodness(boolean[] bits) {
double utility = 0.0;
double rcost = 0.0;
ArrayList<Double> resourceCost = new ArrayList<Double>();
Collections.sort(costUtilities); //sort the costUtilities arraylist
double maxValue = Collections.max(costUtilities); //get the maximum value from the costUtilities arraylist
if(bits[0] && bits[1]){
return -500;
}
if(!bits[0] || bits[1]){
return -1000;
}
for(int x = 1; x < numOfDimensions; x++){
if(bits[x] == costUtilities.contains(maxValue)){
return -1900;
}
}
if (bits[0]) {
resourceCost = costData;
} else if (bits[1]) {
resourceCost = costWlan;
}
for (int i = 2; i <= serviceNames.size(); i++) { //if i = 2, 2<=4
if (bits[i]) {
utility += costUtilities.get(i-2);
rcost += resourceCost.get(i-2);
}
}
if (rcost < batteryCost) {
return utility;
}
return utility * 0.50;
}
}

you can not update UI items on nonUIThread.
search usage of runOnUiThread on google.
call your method in runOnUiThread().
#Override
protected Void doInBackground(Void... params) { //sort this out
runOnUiThread (new Runnable() {
public void run() {
results = runTest("CustomUseCase");
}
}
return null;
}

This explains all: "Can't create handler inside thread that has not called Looper.prepare()" and it seems your TestFactory() method creates a Handler without a Looper.
Inside a secondary Thread a Handler should be like this
....
Looper.prepare();
mHandler = new Handler() {
#Override
public void handleMessage(Message msg) {
// do work with received messages
}
};
Looper.loop();
....
More info : What is the purpose of Looper and how to use it?

Splash Screen using AsyncTask

I have a splash screen using AsyncTask, it will download some data from database and store the data in ArrayList. This ArrayList will be used for RecyclerView in fragments of MainActivity.class.
The problem is when I run the app from Android Studio to my phone, everything works perfectly. But, when I destroy the app and run it manually from my phone it will display blank white screen and then it will crash. And if I run once again after it crashed, the app will work. So, this app will always work only if I run it from Android Studio or after it crashed.
The error says that it is caused by the empty list. If I'm not mistaken, I think the AsyncTask doesn't seem to work properly after the activity is destroyed. But I don't know how to fix it. Please help me to solve this problem.
SplashScreen.java
public class SplashScreenActivity extends AppCompatActivity {
public static Event event;
private static List<Feed> feedList;
private static List<Event> eventList;
private static List<Event> todayList;
private static List<Event> upcomingList;
private static List<Partner> partnerList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_splashscreen);
Time today = new Time(Time.getCurrentTimezone());
today.setToNow();
Config.TODAY_DATE = String.valueOf(today.monthDay) + "-" + String.valueOf(today.month) + "-" + String.valueOf(today.year);
new DownloadData().execute("");
}
class DownloadData extends AsyncTask<String, Integer, String>
{
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
startActivity(new Intent(getBaseContext(), WelcomeActivity.class));
finish();
}
#Override
protected String doInBackground(String... params) {
RequestHandler rh = new RequestHandler();
String JSON_STRING = rh.sendGetRequest(Config.URL_GET_ALL_DATA);
JSONObject jsonObject;
eventList = new ArrayList<>();
todayList = new ArrayList<>();
upcomingList = new ArrayList<>();
partnerList = new ArrayList<>();
feedList = new ArrayList<>();
try {
jsonObject = new JSONObject(JSON_STRING);
JSONArray getEvent = jsonObject.getJSONArray(Config.TAG_JSON_EVENT);
for (int i = 0; i < getEvent.length(); i++) {
int id = getEvent.getJSONObject(i).getInt(Config.TAG_ID);
int eoId = getEvent.getJSONObject(i).getInt(Config.TAG_EO_ID);
String eoName = getEvent.getJSONObject(i).getString(Config.TAG_EO_NAME);
String title = getEvent.getJSONObject(i).getString(Config.TAG_TITLE);
String day = getEvent.getJSONObject(i).getString(Config.TAG_DAY);
String date = getEvent.getJSONObject(i).getString(Config.TAG_DATE);
int price = getEvent.getJSONObject(i).getInt(Config.TAG_PRICE);
event = new Event(id, eoId, eoName, title, day, date, price);
eventList.add(event);
if(Config.TODAY_DATE.equals(event.getDate())){
todayList.add(event);
} else {
upcomingList.add(event);
}
}
JSONArray getPartner = jsonObject.getJSONArray(Config.TAG_JSON_PARTNER);
for (int i = 0; i < getPartner.length(); i++) {
int pId = getPartner.getJSONObject(i).getInt(Config.TAG_ID);
String pName = getPartner.getJSONObject(i).getString(Config.TAG_NAME);
String pEmail = getPartner.getJSONObject(i).getString(Config.TAG_EMAIL);
String pPhone = getPartner.getJSONObject(i).getString(Config.TAG_PHONE);
String pPhoto = getPartner.getJSONObject(i).getString(Config.TAG_PHOTO_URL);
Partner partner = new Partner(pId, pName, pEmail, pPhone, pPhoto);
partnerList.add(partner);
}
JSONArray getArticle = jsonObject.getJSONArray(Config.TAG_JSON_ARTICLE);
for (int i = 0; i < getArticle.length(); i++) {
int feedId = getArticle.getJSONObject(i).getInt(Config.TAG_ID);
String feedAuthor = getArticle.getJSONObject(i).getString(Config.TAG_FEED_AUTHOR);
String feedTitle = getArticle.getJSONObject(i).getString(Config.TAG_FEED_TITLE);
String feedContent = getArticle.getJSONObject(i).getString(Config.TAG_FEED_CONTENT);
String feedDate = getArticle.getJSONObject(i).getString(Config.TAG_FEED_DATE);
String feedThumbnail = getArticle.getJSONObject(i).getString(Config.TAG_FEED_THUMBNAIL);
Feed feed = new Feed(feedId, feedAuthor, feedTitle, feedContent, feedDate, feedThumbnail);
feedList.add(feed);
}
} catch (JSONException e) {
e.printStackTrace();
}
return JSON_STRING;
}
}
public static List<Feed> getFeedList(){ return feedList;}
public static List<Event> getEventList() {return eventList;}
public static List<Event> getTodayList() { return todayList;}
public static List<Event> getUpcomingList() { return upcomingList;}
public static List<Partner> getPartnerList() {return partnerList;}
}
DiscoverFragment.java
public class DiscoverFragment extends Fragment implements ViewPager.OnPageChangeListener, View.OnClickListener {
protected View view;
private LinearLayout pager_indicator;
private int dotsCount;
private ImageView[] dots;
private List<Feed> feedList;
private List<Event> eventList;
private List<Partner> partnerList;
public DiscoverFragment() {}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_discover, container, false);
RecyclerView recyclerViewEvent = (RecyclerView) view.findViewById(R.id.discover_event_recycler_view);
RecyclerView recyclerViewPartner = (RecyclerView) view.findViewById(R.id.discover_partner_recycler_view);
ClickableViewPager intro_images = (ClickableViewPager) view.findViewById(R.id.pager_introduction);
pager_indicator = (LinearLayout) view.findViewById(R.id.viewPagerCountDots);
eventList = SplashScreenActivity.getEventList();
partnerList = SplashScreenActivity.getPartnerList();
feedList = SplashScreenActivity.getFeedList();
EventAdapter eventAdapter = new EventAdapter(getContext(), eventList);
DiscoverPartnerAdapter discoverPartnerAdapter = new DiscoverPartnerAdapter(getContext(), partnerList);
DiscoverFeedAdapter mAdapter = new DiscoverFeedAdapter(getContext(), feedList);
final LinearLayoutManager layoutManagerEvent = new LinearLayoutManager(getContext());
final LinearLayoutManager layoutManagerPartner = new LinearLayoutManager(getContext());
layoutManagerEvent.setOrientation(LinearLayoutManager.HORIZONTAL);
layoutManagerPartner.setOrientation(LinearLayoutManager.HORIZONTAL);
addBottomDots(0);
intro_images.setAdapter(mAdapter);
intro_images.setCurrentItem(0);
intro_images.addOnPageChangeListener(this);
intro_images.setOnItemClickListener(new ClickableViewPager.OnItemClickListener() {
#Override
public void onItemClick(int position) {
Config.FEED_ID = position;
startActivity(new Intent(getContext(), ArticleActivity.class));
}
});
return view;
}
private void addBottomDots(int currentPage) {
dots = new ImageView[feedList.size()]; //the problem
pager_indicator.removeAllViews();
for (int i = 0; i < dots.length; i++) {
dots[i] = new ImageView(getContext());
dots[i].setImageDrawable(getResources().getDrawable(R.drawable.nonselecteditem_dot));
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT
);
params.setMargins(4, 0, 4, 0);
pager_indicator.addView(dots[i], params);
}
if (dots.length > 0)
dots[currentPage].setImageDrawable(getResources().getDrawable(R.drawable.selecteditem_dot));
}
#Override
public void onClick(View v) {
switch (v.getId()) {
}
}
#Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
#Override
public void onPageSelected(int position) {
addBottomDots(position);
for (int i = 0; i < dotsCount; i++) {
dots[i].setImageDrawable(getResources().getDrawable(R.drawable.nonselecteditem_dot));
}
dots[position].setImageDrawable(getResources().getDrawable(R.drawable.selecteditem_dot));
}
}
LogCat
01-29 00:40:57.565 32535-32535/com.irmaelita.esodiaapp E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.irmaelita.esodiaapp, PID: 32535
java.lang.NullPointerException: Attempt to invoke interface method 'int java.util.List.size()' on a null object reference
at com.irmaelita.esodiaapp.fragment.DiscoverFragment.addBottomDots(DiscoverFragment.java:181)
at com.irmaelita.esodiaapp.fragment.DiscoverFragment.onCreateView(DiscoverFragment.java:158)

feedList is null. You create feedList instance when DownloadData task is executed. But you call feedList.size() in addBottomDots when fragment view should be created. So, most probably addBottomDots is called before DownloadData task is executed. You need to fix it.

The feedlist in your discover fragment is going empty while initializing. Please set a null check before doing so.It not about running from android studio.If I have understood it correctly you are trying to access a list from splasScreen activity after finishing it. ie in post execute you finish the current activity and the fragment is in main activity,so the list is going null.So if this is the case (and please correct me if not) then either download the data somewhere centrally or best way send it to main activity with intent and use it there. Also when running from android studio kill the app manually and run it again,while the phone is connected and see if it crashes in current scenario.

Send your data from doInBackground to MainActivity with sendBroadcast
Add broadcast method in DownloadData class
private void broadcast(SplashParcel parcel) {
Intent i = new Intent("splash_parcel");
i.putExtra("values", parcel);
sendBroadcast(i);
}
#Override
protected String doInBackground(String... params) {
// your code
// ..
try {
// your code
// ..
// send splashParcel to MainActivity
SplashParcel splashParcel = new SplashParcel(feedList, eventList, todayList, upcomingList, partnerList);
broadcast (splashParcel);
} catch (JSONException e) {
e.printStackTrace();
}
return JSON_STRING;
}
Add new class SplashParcel.java
public class SplashParcel implements Parcelable {
public static final Creator<SplashParcel> CREATOR = new Creator<SplashParcel>() {
#Override
public SplashParcel createFromParcel(Parcel in) {
return new SplashParcel(in);
}
#Override
public SplashParcel[] newArray(int size) {
return new SplashParcel[size];
}
};
private static List<Feed> _feedList;
private static List<Event> _eventList;
private static List<Event> _todayList;
private static List<Event> _upcomingList;
private static List<Partner> _partnerList;
protected SplashParcel(Parcel in) {
_feedList = new ArrayList<Feed>();
in.readList(_feedList, null);
_eventList = new ArrayList<Event>();
in.readList(_eventList, null);
_todayList = new ArrayList<Event>();
in.readList(_todayList, null);
_upcomingList = new ArrayList<Event>();
in.readList(_upcomingList, null);
_partnerList = new ArrayList<Partner>();
in.readList(_partnerList, null);
}
public SplashParcel(List<Feed> feedList, List<Event> eventList, List<Event> todayList, List<Event> upcomingList, List<Partner> partnerList) {
_feedList = feedList;
_eventList = eventList;
_todayList = todayList;
_upcomingList = upcomingList;
_partnerList = partnerList;
}
public SplashParcel() {
}
public List<Feed> getFeedList() {
return _feedList;
}
public void setFeedList(List<Feed> feedList) {
_feedList = feedList;
}
public List<Event> getEventList() {
return _eventList;
}
public void setEventList(List<Event> eventList) {
_eventList = eventList;
}
public List<Event> getTodayList() {
return _todayList;
}
public void setTodayList(List<Event> todayList) {
_todayList = todayList;
}
public List<Event> getUpcomingList() {
return _upcomingList;
}
public void setUpcomingList(List<Event> upcomingList) {
_upcomingList = upcomingList;
}
public List<Partner> getPartnerList() {
return _partnerList;
}
public void setPartnerList(List<Partner> partnerList) {
_partnerList = partnerList;
}
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel parcel, int i) {
parcel.writeList(_feedList);
parcel.writeList(_eventList);
parcel.writeList(_todayList);
parcel.writeList(_upcomingList);
parcel.writeList(_partnerList);
}
}
MainActivity.java
// member variable
private BroadcastReceiver _splashReceiver;
private Bundle _bundle = new Bundle();
#Override
protected void onResume() {
super.onResume();
splashReceiver();
}
// receive splashParcel from SplashScreenActivity
private void splashReceiver() {
if (_splashReceiver == null) {
_splashReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
SplashParcel splashParcel = intent.getParcelableExtra("values");
if (splashParcel != null) {
// save splashParcel into _budle
_bundle.putParcelable("splash_parcel", splashParcel);
}
}
};
registerReceiver(_splashReceiver, new IntentFilter("splash_parcel"));
}
}
//Send _bundle to DiscoverFragment
private void showDiscoverFragment(){
if(_bundle != null) {
// create instance of discoverFragment with passing _bundle as arguments
DiscoverFragment discoverFragment = new DiscoverFragment();
discoverFragment.setArguments(_bundle);
// replace activity_main.xml with discoverFragment
getSupportFragmentManager().beginTransaction().replace(R.id.main_container, discoverFragment).addBackStack(null).commit();
}
}
In onCreateView of DiscoverFragment:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
SplashParcel splashParcel = getArguments().getParcelable("splash_parcel");
if(splashParcel != null) {
// your splashParcel ready in here
List<Feed> feedList = splashParcel.getFeedList()
List<Event> eventList = splashParcel.getEventList()
List<Event> todayList = splashParcel.getTodayList();
List<Event> upcommingList = splashParcel.getUpcomingList();
List<Partner> partnerList = splashParcel.getPartnerList();
}
}