Splash Screen using AsyncTask - java

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();
}
}

Related

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 ();
}

App crashes after theme change (apparently caused by fragment)

My Main Activity has three tabs. Each tab is a fragment. Now if you change the theme (white and dark are available), the activity is being recreated so that the change takes effect. But the app crashes.
How I deal with the fragments:
if (savedInstanceState == null) {
pageadapter = new SectionsPageAdapter(getSupportFragmentManager());
rFragMore = new RoomlistFragmentMore();
rFragMyRooms = new RoomlistFragmentMyRooms();
rFragFavs = new RoomlistFragmentFavorites();
} else {
rFragMyRooms = (RoomlistFragmentMyRooms)pageadapter.getItem(0);
rFragFavs = (RoomlistFragmentFavorites)pageadapter.getItem(1);
rFragMore = (RoomlistFragmentMore)pageadapter.getItem(2);
pageadapter.clearAdapter();
pageadapter = new SectionsPageAdapter(getSupportFragmentManager());
}
How I set up the Adapter:
private void setupViewPager(ViewPager viewPager) {
pageadapter.addFragment(rFragMyRooms, getResources().getString(R.string.myrooms));
pageadapter.addFragment(rFragFavs, getResources().getString(R.string.favorites));
pageadapter.addFragment(rFragMore, getResources().getString(R.string.more));
viewPager.setAdapter(pageadapter);
}
My Adapter:
public class SectionsPageAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
public void clearAdapter() {
mFragmentList.clear();
mFragmentTitleList.clear();
}
public SectionsPageAdapter(FragmentManager fm) {
super(fm);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
}
And the Error Log:
java.lang.NullPointerException: Attempt to invoke virtual method 'java.io.FileInputStream android.content.Context.openFileInput(java.lang.String)' on a null object reference
at com.yannick.mychatapp.RoomlistFragmentMore.readFromFile(RoomlistFragmentMore.java:246)
at com.yannick.mychatapp.RoomlistFragmentMore.addRoomToList(RoomlistFragmentMore.java:121)
at com.yannick.mychatapp.RoomlistFragmentMore.access$000(RoomlistFragmentMore.java:46)
at com.yannick.mychatapp.RoomlistFragmentMore$1.onDataChange(RoomlistFragmentMore.java:79)
at com.google.firebase.database.core.ValueEventRegistration.fireEvent(com.google.firebase:firebase-database##16.0.4:75)
at com.google.firebase.database.core.view.DataEvent.fire(com.google.firebase:firebase-database##16.0.4:63)
at com.google.firebase.database.core.view.EventRaiser$1.run(com.google.firebase:firebase-database##16.0.4:55)
at android.os.Handler.handleCallback(Handler.java:873)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
EDIT: the code of RoomlistFragmentMore
public class RoomlistFragmentMore extends Fragment {
private ListView listView;
private List<HashMap<String, String>> listItems = new ArrayList<>();
private String raumname, theme;
private static String userID = "";
private SimpleAdapter adapter;
private DatabaseReference root = FirebaseDatabase.getInstance().getReference().getRoot().child("rooms");
private ArrayList<Room> raumliste = new ArrayList<>();
private TextView keinraumgefunden;
private String[] kat;
private static final String TAG = "RoomlistFragmentMore";
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.roomlist_fragment_more,container,false);
listView = view.findViewById(R.id.listView);
keinraumgefunden = view.findViewById(R.id.keinraumgefunden);
kat = getResources().getStringArray(R.array.categories);
theme = readFromFile("mychatapp_theme.txt");
adapter = new SimpleAdapter(getActivity(), listItems, R.layout.listlayout,
new String[]{"name", "kat", "lock", "newest"},
new int[]{R.id.raumname, R.id.raumkat, R.id.raumlock, R.id.raumdatum});
listView.setAdapter(adapter);
root.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
addRoomToList(dataSnapshot);
}
#Override
public void onCancelled(DatabaseError databaseError) {
Toast.makeText(getActivity(), R.string.nodatabaseconnection, Toast.LENGTH_SHORT).show();
}
});
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
int position = listView.getPositionForView(view);
String roomname = listItems.get(position).values().toArray()[0].toString();
Room room = findRoom(raumliste, roomname);
request_password(room, position);
}
});
adapter.registerDataSetObserver(new DataSetObserver() {
#Override
public void onChanged() {
if (raumliste.isEmpty()) {
keinraumgefunden.setText(R.string.noroomfound);
} else {
keinraumgefunden.setText("");
}
}
});
return view;
}
private void addRoomToList(DataSnapshot dataSnapshot) {
HashMap<String, String> raeume = new HashMap<>();
raumliste.clear();
for(DataSnapshot uniqueKeySnapshot : dataSnapshot.getChildren()){
String name = uniqueKeySnapshot.getKey();
for(DataSnapshot roomSnapshot : uniqueKeySnapshot.getChildren()){
Room room = roomSnapshot.getValue(Room.class);
room.setRaumname(name);
if (!room.getPasswd().equals(readFromFile("mychatapp_raum_" + name + ".txt"))) {
raeume.put(name, kat[Integer.parseInt(room.getCaty())]+"/"+"\uD83D\uDD12"+"/");
raumliste.add(room);
}
break;
}
}
listItems.clear();
Iterator it = raeume.entrySet().iterator();
while (it.hasNext()){
HashMap<String, String> resultsMap = new HashMap<>();
Map.Entry pair = (Map.Entry)it.next();
resultsMap.put("name", pair.getKey().toString());
String daten = pair.getValue().toString();
String caty = daten.substring(0, daten.indexOf("/"));
String lock = daten.substring(daten.indexOf("/")+1, daten.lastIndexOf("/"));
String time = daten.substring(daten.lastIndexOf("/")+1, daten.length());
String newestTime = "";
int index = 0;
resultsMap.put("kat", caty);
resultsMap.put("lock", lock);
resultsMap.put("newest", newestTime);
if (time.equals("")) {
listItems.add(resultsMap);
} else {
listItems.add(index, resultsMap);
}
}
adapter.notifyDataSetChanged();
}
private void request_password(final Room room, final int position) {
LayoutInflater inflater = LayoutInflater.from(getContext());
View view = inflater.inflate(R.layout.enter_room, null);
raumname = room.getRaumname();
userID = readFromFile("mychatapp_userid.txt");
final EditText input_field = view.findViewById(R.id.room_password);
AlertDialog.Builder builder;
if (theme.equals(getResources().getStringArray(R.array.themes)[1])) {
builder = new AlertDialog.Builder(new ContextThemeWrapper(getActivity(), R.style.AlertDialogDark));
} else {
builder = new AlertDialog.Builder(getActivity());
}
builder.setTitle(R.string.pleaseenterpassword);
builder.setView(view);
builder.setCancelable(false);
builder.setPositiveButton(R.string.confirm, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
}
});
builder.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
View view = ((AlertDialog) dialogInterface).getCurrentFocus();
if (view != null) {
InputMethodManager imm = (InputMethodManager)getActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
}
dialogInterface.cancel();
}
});
final AlertDialog alert = builder.create();
alert.setOnShowListener(new DialogInterface.OnShowListener() {
#Override
public void onShow(DialogInterface dialog) {
Button b = alert.getButton(AlertDialog.BUTTON_POSITIVE);
b.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (input_field.getText().toString().trim().equals(room.getPasswd())) {
Intent tabIntent = new Intent("tab");
LocalBroadcastManager.getInstance(getActivity()).sendBroadcast(tabIntent);
Intent intent = new Intent(getActivity(), ChatActivity.class);
intent.putExtra("room_name", room.getRaumname());
intent.putExtra("user_id",userID);
updateRoomList(position);
writeToFile(room.getPasswd(),"mychatapp_raum_" + raumname + ".txt");
alert.cancel();
startActivity(intent);
} else {
Toast.makeText(getActivity(), R.string.wrongpassword, Toast.LENGTH_SHORT).show();
}
}
});
}
});
alert.show();
}
public Room findRoom(ArrayList<Room> raumliste, String raumname) {
for (Room room : raumliste) {
if (room.getRaumname().equals(raumname)) {
return room;
}
}
return null;
}
public void writeToFile(String text, String datei) {
Context context = getActivity();
try {
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(context.openFileOutput(datei, Context.MODE_PRIVATE));
outputStreamWriter.write(text);
outputStreamWriter.close();
}
catch (IOException e) {
Log.e("Exception", "File write failed: " + e.toString());
}
}
public String readFromFile(String datei) {
Context context = getActivity();
String erg = "";
try {
InputStream inputStream = context.openFileInput(datei);
if ( inputStream != null ) {
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
String receiveString = "";
StringBuilder stringBuilder = new StringBuilder();
while ( (receiveString = bufferedReader.readLine()) != null ) {
stringBuilder.append(receiveString);
}
inputStream.close();
erg = stringBuilder.toString();
}
}
catch (FileNotFoundException e) {
Log.e("login activity", "File not found: " + e.toString());
} catch (IOException e) {
Log.e("login activity", "Can not read file: " + e.toString());
}
return erg;
}
private void updateRoomList(int position) {
listItems.remove(position);
adapter.notifyDataSetChanged();
}
}
The NullPointerException occured while onDataChange() was executed (you can see this by reading the stack trace). More specifically, readFromFile() needs a valid Context to open a file.
Since your app crashed we know that getActivity() did return null. How can this happen?
You add the ValueEventListener in onCreateView(). At this point in time, the Fragment has a valid Context (see the documentation for an explanation of the Lifecycle), so all is well for the moment.
But since you do not remove the ValueEventListener, it will continue to fire even if the Fragment is temporarily not attached to the Activity because the user swiped to the next page. The Fragment won't be garbage collected because you keep it in a list and reuse it.
This approach is basically ok if you implement null checks to avoid accessing the Activity, the Context or Views in general while they are not present. Of course, you could consider a stronger separation of the data and the View layer as suggested in this guide to app architecture

Data parsed from Json cant fetch properly when add another argument in constructor

This is Fist time i'm asking question!! so bear with me.
The application is project(popular movie stage 2) from udacity where i need to fetch info of movies like tilte or poster_path or backdrop_path.
so when i fetch data from json it works perfectly fine but when i add another argument String backdrop in my Movies.java class.then getmBackdrop() shows empty and i couldn't get the data of backdrop overview and vote.but if i delete backdrop from constructor than it works fine. i dont know what is happening please help me.
this is Movies.javaclass
public class Movies implements Parcelable {
//Movies Data
public long mID;
private String mPosterPath;
private String mReleaseDate;
private String mTitle;
private String mVote;
private String mOverview;
private String mBackdrop;
private ArrayList<Trailers> trailers;
private ArrayList<Reviews> reviews;
public Movies() {
}
public Movies(String title, String releaseDate, String posterPath,
String backdrop,String vote, String overview) {
// this.mID=id;
this.mTitle = title;
this.mReleaseDate = releaseDate;
this.mPosterPath = posterPath;
this.mBackdrop = backdrop;
this.mVote = vote;
this.mOverview = overview;
this.trailers = new ArrayList<>();
this.reviews = new ArrayList<>();
}
public long getID(){ return mID ;}
public String getmBackdrop() { return mBackdrop; }
public String getPosterPath() {
return mPosterPath;
}
public String getTitle() {
return mTitle;
}
public String getReleaseDate() {
return mReleaseDate;
}
public String getOverview() {
return mOverview;
}
public String getVote() {
return mVote +"/10";
}
public void setTrailers(ArrayList<Trailers> trailers) {
this.trailers = trailers;
}
public void setReviews(ArrayList<Reviews> reviews) {
this.reviews = reviews;
}
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeLong(mID);
dest.writeString(mTitle);
dest.writeString(mReleaseDate);
dest.writeString(mPosterPath);
dest.writeValue(mBackdrop);
dest.writeString(mVote);
dest.writeString(mOverview);
}
protected Movies(Parcel in) {
mID = in.readLong();
mTitle = in.readString();
mReleaseDate = in.readString();
mPosterPath = in.readString();
mBackdrop = in.readString();
mVote = in.readString();
mOverview = in.readString();
}
public static final Creator<Movies> CREATOR = new Creator<Movies>() {
public Movies createFromParcel(Parcel source) {
return new Movies(source);
}
public Movies[] newArray(int size) {
return new Movies[size];
}
};
}
MoviepediaJsonUtils.java where i'm parsing data
public class MoviepediaJsonUtils {
public static ArrayList<Movies> getParseMovieJson(String jsonMovies) throws JSONException {
final String IMAGE_BASE_URL = "https://image.tmdb.org/t/p/w500/";
final String BACKDROP_URL= "https://image.tmdb.org/t/p/w1280/";
JSONObject movieJson = new JSONObject(jsonMovies);
JSONArray movieArray = movieJson.getJSONArray("results");
ArrayList<Movies> movieArrayList = new ArrayList<>();
for (int i = 0; i < movieArray.length(); i++) {
JSONObject movieObject = movieArray.getJSONObject(i);
long id = movieObject.getLong("id");
String title = movieObject.getString("title");
String release_date = movieObject.getString("release_date");
String poster_path = movieObject.getString("poster_path");
String backdrop = movieObject.getString("backdrop_path");
String vote_average = movieObject.getString("vote_average");
String overview = movieObject.getString("overview");
Movies movies = new Movies(title, release_date,
IMAGE_BASE_URL + poster_path, BACKDROP_URL+backdrop,vote_average, overview);
movieArrayList.add(movies);
}
return movieArrayList;
}
public static String getResponseFromHttpUrl(InputStream stream) throws IOException {
Scanner scanner = new Scanner(stream);
scanner.useDelimiter("\\A");
boolean hasInput = scanner.hasNext();
if (hasInput) {
return scanner.next();
} else {
return null;
}
}
}
MainActivityFragments.java
public class MainActivityFragments extends Fragment {
private static final int COLUMN = 2;
private RecyclerView mRecyclerView;
SharedPreferences mSettings;
GridLayoutManager mGridLayoutManager;
private SharedPreferences.Editor mEditor;
private static final String SHARED_KEY_SORT = "sort";
private static final String POPULARITY = "popular";
private static final String RATINGS = "top_rated";
public static String[] backdrop;
public static final String SAVE_LAST_UPDATE_ORDER = "save_last_update_order";
private String mLastUpdateOrder;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater,
#Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.poster_fragment, container, false);
if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT){
mGridLayoutManager = new GridLayoutManager(getActivity(),2, LinearLayoutManager.VERTICAL,false);
}else{
mGridLayoutManager = new GridLayoutManager(getActivity(), 4,LinearLayoutManager.VERTICAL,false);
}
mRecyclerView = view.findViewById(R.id.rv_movies);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.setLayoutManager(mGridLayoutManager);
mSettings = PreferenceManager.getDefaultSharedPreferences(getActivity());
mEditor = mSettings.edit();
mEditor.apply();
mRecyclerView.setAdapter(new MoviesAdapter(getActivity(), new ArrayList<Movies>()));
return view;
}
#Override
public void onStart() {
super.onStart();
if (needToUpdateUi()) {
updateUi();
}
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putString(SAVE_LAST_UPDATE_ORDER, mLastUpdateOrder);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
if (savedInstanceState != null) {
mLastUpdateOrder = savedInstanceState.getString(SAVE_LAST_UPDATE_ORDER);
}
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
updateUi();
}
// OnCreateOptionMenues will be here
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.poster_fragment, menu);
Drawable drawable = menu.findItem(R.id.icon).getIcon();
if (drawable != null) {
drawable.mutate();
drawable.setColorFilter(Color.WHITE, PorterDuff.Mode.SRC_ATOP);
}
}
// OnOptionitemSelected
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.poularity:
mEditor.putString(SHARED_KEY_SORT, POPULARITY);
mEditor.apply();
updateUi();
item.setChecked(true);
return true;
case R.id.top_rated:
mEditor.putString(SHARED_KEY_SORT, RATINGS);
mEditor.apply();
updateUi();
item.setChecked(true);
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onPrepareOptionsMenu(Menu menu) {
super.onPrepareOptionsMenu(menu);
String sortBy = mSettings.getString(SHARED_KEY_SORT, POPULARITY);
if (sortBy.equals(POPULARITY)) {
menu.findItem(R.id.poularity).setChecked(true);
} else {
menu.findItem(R.id.top_rated).setChecked(true);
}
}
private void updateUi() {
if (isNetworkAvailable()) {
OnTaskCompleted taskCompleted = new OnTaskCompleted() {
#Override
public void onFetchMoviesTaskCompleted(ArrayList<Movies> movies) {
mRecyclerView.setAdapter(new MoviesAdapter(getActivity(), movies));
}
};
MoviesAsyncTask moviesAsyncTask = new MoviesAsyncTask(taskCompleted);
mSettings = PreferenceManager.getDefaultSharedPreferences(getActivity());
String sortBy = mSettings.getString(SHARED_KEY_SORT, POPULARITY);
mLastUpdateOrder = sortBy;
moviesAsyncTask.execute(sortBy);
} else {
Toast.makeText(this.getActivity().getApplicationContext(), "Need Internet Connection", Toast.LENGTH_LONG).show();
}
}
private boolean needToUpdateUi() {
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getActivity());
if (!mLastUpdateOrder.equals(prefs.getString(SHARED_KEY_SORT, POPULARITY))) {
return true;
} else {
return false;
}
}
//Based on a stackoverflow snippet
private boolean isNetworkAvailable() {
ConnectivityManager connectivityManager
= (ConnectivityManager) this.getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
return activeNetworkInfo != null && activeNetworkInfo.isConnected();
}
}
DeatailActivityFragment
public class DetailActivityFragments extends Fragment {
private final String TAG = this.getClass().getSimpleName();
private static final String PARCEL_KEY = "movie_parcel";
Movies mMovie;
OnTaskCompleted mlistener;
ArrayList<Trailers> mTrailers;
ArrayList<Reviews> mReviews;
ImageView poster;
ImageView backdrop;
public DetailActivityFragments() {
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.activity_detail_fragment,
container, false);
Movies parceableExtra = getActivity().getIntent().getParcelableExtra(PARCEL_KEY);
poster = view.findViewById(R.id.poster_IV);
TextView title = view.findViewById(R.id.title_TV);
TextView releaseDate = view.findViewById(R.id.relaesedate_TV);
TextView vote = view.findViewById(R.id.vote_TV);
TextView overView = view.findViewById(R.id.overview_TV);
backdrop = view.findViewById(R.id.image_id);
final FloatingActionButton fab1 = view.findViewById(R.id.fab);
//String gotPosition = getStringExtra("position");
//intGotPosition=Integer.parseInt(gotPosition);
// String url = "https://image.tmdb.org/t/p/w1280"+DetailActivityFragments.backdrop[intGotPosition];
title.setText(parceableExtra.getTitle());
releaseDate.setText(parceableExtra.getReleaseDate());
vote.setText(parceableExtra.getVote());
overView.setText(parceableExtra.getOverview());
Picasso.with(view.getContext()).load(parceableExtra.getPosterPath())
.into(poster);
Picasso.with(this.getActivity()).load( parceableExtra.getmBackdrop())
.error(R.drawable.sam).into(backdrop);
fab1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Context context = view.getContext();
Intent i=new Intent(context , TrailerActivity.class);
startActivity(i);
}
});
return view;
}
}
MoviesAsyncTask.java
public class MoviesAsyncTask extends AsyncTask<String, Void, ArrayList<Movies>> {
private final String LOG_TAG = MoviesAsyncTask.class.getSimpleName();
final String MY_API_KEY = "removed deliberately";
ArrayList<Movies> mMovies;
private OnTaskCompleted mListener;
public MoviesAsyncTask(OnTaskCompleted listener) {
mListener = listener;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected ArrayList<Movies> doInBackground(String... params) {
if (params.length == 0) {
return null;
}
final String MOVIEDB_BASE_URL =
"https://api.themoviedb.org/3/movie/";
final String APIKEY = "api_key";
Uri builtUri = Uri.parse(MOVIEDB_BASE_URL).buildUpon()
.appendPath(params[0])
.appendQueryParameter(APIKEY, MY_API_KEY)
.build();
URL url = null;
try {
url = new URL(builtUri.toString());
} catch (MalformedURLException e) {
e.printStackTrace();
}
URLConnection connection = null;
try {
connection = url.openConnection();
} catch (IOException e) {
e.printStackTrace();
}
String response = null;
try {
response = MoviepediaJsonUtils.getResponseFromHttpUrl(connection.getInputStream());
} catch (IOException e) {
e.printStackTrace();
}
try {
return MoviepediaJsonUtils.getParseMovieJson(response);
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(ArrayList<Movies> movies) {
super.onPostExecute(movies);
mListener.onFetchMoviesTaskCompleted(movies);
mMovies = movies;
}
}
Try to add your string at the end of your class or remove all the parcelable generated code, add your string, then apply again the parcelable implementation.
This happens because you're not updating the parcel methods.

set image bitmap to imageView adapter

At the moment i am using custom adapter/recycle view to build a simple image and a small galery under the image, every time when i click on one of the images below it loads the image in the main imageView above.
My problem at the moment is, that everytime i click on the images on the galery i do a request for the image, i get the id of the clicked image and load again the image to display it above.
I don't like very well my solution, i want to get the bitmap of the clicked image and display it in the imageView above.
So in my main activity i do a simple request to get the main image, the rest of the images are loading in another reques of my activity that loads a recycle view with all images.
here is the activity:
public class PhotosForPlant extends AppCompatActivity implements IResult,PhotosForPlantsAdapter.OnItemClickListener {
RecyclerView recyclerView;
ArrayList<Photo> photos = new ArrayList<Photo>();
VolleyService mVolleyService;
IResult mResultCallback = null;
IResult mResultCallback2 = null;
final String GETREQUEST = "GETCALL";
PhotosForPlantsAdapter adapter;
String token;
TextView familyTxt;
TextView genreTxt;
TextView specieTxt;
TextView specieDescription;
ImageView plantImg;
int familyId;
int genreId;
String familyName;
String genreName;
Double lat = null;
Double lon = null;
Double alt = null;
String time = null;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setTheme(R.style.AppTheme);
setContentView(R.layout.photos_for_plant);
Toolbar myToolbar = (Toolbar) findViewById(R.id.my_toolbar);;
setSupportActionBar(myToolbar);
getSupportActionBar().setDisplayShowTitleEnabled(false);
findViewById(R.id.user_ic2).setVisibility(View.GONE);
TextView toolbarText = (TextView) myToolbar.findViewById(R.id.toolbar_title);
toolbarText.setText("Dados planta");;
familyTxt = (TextView)findViewById(R.id.FamilyName);
genreTxt = (TextView)findViewById(R.id.GenreName);
specieTxt = (TextView)findViewById(R.id.SpecieName);
specieDescription = (TextView)findViewById(R.id.specieDescription);
plantImg = (ImageView)findViewById(R.id.plantImage);
token = checkForToken();
getAllPhotos();
getSpecificPlant();
}
private void getSpecificPlant() {
String id = getIntent().getExtras().getString("plantId");
final String URL = "http://109d0157.ngrok.io/plants/" + id;
getSpecificVolleyCallback();
mVolleyService = new VolleyService(mResultCallback2,this);
mVolleyService.getDataObjectVolley(GETREQUEST,URL,token);
}
private void getAllPhotos() {
String id = getIntent().getExtras().getString("plantId");
final String URL = "http://109d0157.ngrok.io/fotos/" + id + "/plants";
getFotosForPlantVolleyCallback();
mVolleyService = new VolleyService(mResultCallback,this);
mVolleyService.getDataVolley(GETREQUEST,URL,token);
recyclerView = (RecyclerView)findViewById(R.id.gallery);
recyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager = new GridLayoutManager(getApplicationContext(),5,GridLayoutManager.VERTICAL, false);
recyclerView.setLayoutManager(layoutManager);
adapter = new PhotosForPlantsAdapter(getApplicationContext(), photos,this);
recyclerView.setAdapter(adapter);
}
private void getSpecificVolleyCallback() {
mResultCallback2 = new IResult() {
#Override
public void notifySuccess(String requestType, JSONObject response) {
try {
Log.d("ENTREIAQUI","ENTREI");
String specie = response.getString("specie");
loadImage(specie);
familyName = response.getJSONObject("genre").getJSONObject("family").getString("name");
genreName = response.getJSONObject("genre").getString("name");
genreId = response.getJSONObject("genre").getInt("id");
genreTxt.setText(genreName);
specieTxt.setText(specie);
familyTxt.setText(familyName);
specieDescription.setText(response.getString("description"));
familyId = response.getJSONObject("genre").getJSONObject("family").getInt("id");
} catch (JSONException e) {
e.printStackTrace();
}
}
#Override
public void notifySuccess(String requestType, JSONArray response) {
Log.d("ENTREIAQUI","ENTREI");
}
#Override
public void notifyError(String requestType, VolleyError error) {
Log.d("erro!",error.toString());
Log.d("ENTREIAQUI","ENTREI");
}
};
}
void getFotosForPlantVolleyCallback(){
mResultCallback = new IResult() {
#Override
public void notifySuccess(String requestType, JSONObject response) {
}
#Override
public void notifySuccess(String requestType, JSONArray response) {
Photo photo;
// iterate over the JSONArray response
for (int i=0; i < response.length(); i++) {
try {
JSONObject object = response.getJSONObject(i); // get the individual object from JSONArray
Log.d("objeto",object.toString());
int id = Integer.parseInt(object.getString("id")); // get the unique identifier from the object
if(lat != null && lon != null && alt != null){
lat = Double.parseDouble(object.getString("lat"));
lon = Double.parseDouble(object.getString("lon"));
alt = Double.parseDouble(object.getString("altitude"));
}
time = object.getString("date");
String path = object.getString("image");
photo = new Photo(path,id,lat,lon,alt,time); // construct the object
photos.add(photo); // add the object to the arraylist so it can be used on the cardLayout
} catch (JSONException e) {
e.printStackTrace();
}
}
adapter.notifyDataSetChanged();
}
#Override
public void notifyError(String requestType, VolleyError error) {
Log.d("resposta",error.toString());
}
};
}
public void genrePressed(View view){
Intent i = new Intent(this,SpecieLibrary.class);
i.putExtra("id",String.valueOf(genreId));
i.putExtra("name",String.valueOf(genreName));
startActivity(i);
}
public void familyPressed(View view){
Intent i = new Intent(this,GenreLibrary.class);
i.putExtra("id",String.valueOf(familyId));
i.putExtra("name",String.valueOf(familyName));
startActivity(i);
}
#Override
public void notifySuccess(String requestType, JSONObject response) {
}
#Override
public void notifySuccess(String requestType, JSONArray response) {
}
#Override
public void notifyError(String requestType, VolleyError error) {
}
public String checkForToken() {
SharedPreferences sharedPref = getSharedPreferences("user", MODE_PRIVATE);
String tokenKey = getResources().getString(R.string.token);
String token = sharedPref.getString(getString(R.string.token), tokenKey); // take the token
return token;
}
public void loadImage(String specie){
String url = "http://109d0157.ngrok.io/images/" + specie + "/Thumbnail.jpg";
Picasso.with(PhotosForPlant.this)
.load(url)
.into(plantImg);
}
#Override
public void onRowClick(int position, int id,String path, View view) {
String url = "http://109d0157.ngrok.io/" + path;
Picasso.with(PhotosForPlant.this)
.load(url)
.into(plantImg);
}
}
the loadImage, is where i load the main image and then i have the onRowClick that comes from my custom adapter, i get the path of the clicked row there and so i load it again, but what i need is to get somehow the bitmap there and setImageResource on the plantImg.
Here is my adapter:
public class PhotosForPlantsAdapter extends RecyclerView.Adapter<PhotosForPlantsAdapter.ViewHolder> {
private ArrayList<Photo> photos;
private Context context;
private OnItemClickListener listener;
public interface OnItemClickListener {
void onRowClick(int position,int id,String path, View view);
}
public PhotosForPlantsAdapter(Context context, ArrayList<Photo> photos,OnItemClickListener listener) {
this.photos = photos;
this.context = context;
this.listener = listener;
}
#Override
public PhotosForPlantsAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.photos_for_plant_row, viewGroup, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(final PhotosForPlantsAdapter.ViewHolder viewHolder, final int i) {
String urlFoto = photos.get(i).getPath();
String url = "http://109d0157.ngrok.io/" + urlFoto;
viewHolder.img.setScaleType(ImageView.ScaleType.CENTER_CROP);
Picasso.with(context)
.load(url)
.resize(240, 120)
.centerInside()
.into(viewHolder.img);
viewHolder.img.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (listener != null) {
listener.onRowClick(viewHolder.getAdapterPosition(),photos.get(i).getId(),photos.get(i).getPath(), view);
}
}
});
}
#Override
public int getItemCount() {
return photos.size();
}
public class ViewHolder extends RecyclerView.ViewHolder{
private ImageView img;
public ViewHolder(View view) {
super(view);
img = (ImageView) view.findViewById(R.id.img);
}
}
}
try to set Image in this way as bitmap
URL newurl = new URL("http://109d0157.ngrok.io/" + urlFoto);
mIcon_val=BitmapFactory.decodeStream(newurl.openConnection() .getInputStream());
viewHolder.img.setImageBitmap(mIcon_val);
and get Image in this way
Bitmap imgBitmap = ((BitmapDrawable)image.getDrawable()).getBitmap();

Values duplicating when fetching data from database and displaying to ListView

Im new to Android Developement and currently working on an app that should give me the time between first time clicking a button and second time clicking the button and add it to a currently selected customer.
Current Status of App:
I established a connection to da mySql Database using Volley and a local webservice.
It works to insert my customers and time stamps to the table, but when loading times for a specific customer i get a strange result in one case. I tried debugging it but the app keeps crashing on debugging without a message. When not debugging it doesnt crash but shows weird data.
To the problem:
In my main activity called "ZeitErfassen" i have a button to get an overview of all customers display in a ListView.
I create the Listview with a custom ArrayAdapter because i want to pass my objects to the next Activity where my customers are displayed.
So onCreate of the overview of customers i create a new arraylist and fill it with all customers from my database. this list i pass to my customadapter and then set it as my adapter of the Listview.
Now, when i click on an item, i call a php script and pass the customer_id to the query to fetch all times from database where customer_id = customer_id.
Now the part where i get "strange" data...
1.(Source:ZeitErfassen;Destination:AddCustomer) I create a new customer,example xyz, in the app, data gets passed to the database.
2.(Source:ZeitErfassen;Destination:DisplayCustomer) I call my overview for all customers where the ListView is filled with data as described above. At the end ob the List I see the customer i just created,xyz.
3.Go back to Main Activity(ZeitErfassen)
4.(Source:ZeitErfassen;Destination:DisplayCustomer)I open the overview for all customers again, and it shows my last created user two times! so last entry, xyz, entry before last, xyz!
After that, i can open the view as many times as i want, the customer never gets duplicated again!
The debugger stopps after step 2.
Now when i click on the new customers, it calls the script to fetch the times by customer_id.
One of the xyz entrys display the correct times from database.
The second one, i just found out, display the times where customer_id="". In the database the value for "" is 0.
I have no clue where the second customer suddenly appears from and debugging didnt help me either -.-
When i close the app an open it again, there ist just one entry for the user that was visible twice before closing the app. It doesnt duplicate on opening view...
Here is my code..
Main Activity ZeitErfassen
public class ZeitErfassen extends AppCompatActivity {
public static LinkedList<Kunde> kunden = new LinkedList<Kunde>();
boolean running = false;
long startTime,endTime,totalTime;
private SharedPreferences app_preferences;
private SharedPreferences.Editor editor;
private TextView displayTime;
public Button startEndButton;
private ArrayAdapter<String> adapter;
private Spinner spinner;
public static Kunde selectedCustomer;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_zeit_erfassen);
//Einstellungen laden
app_preferences = getApplicationContext().getSharedPreferences("MyPref", MODE_PRIVATE);
startTime= app_preferences.getLong("startTime", 0);
endTime = app_preferences.getLong("endTime", 0);
running = app_preferences.getBoolean("running", false);
displayTime = (TextView)findViewById(R.id.zeit_bei_Kunde);
displayTime.setText((CharSequence) app_preferences.getString("zeitAnzeige", "Zeit bei Kunde"));
startEndButton = (Button)findViewById(R.id.start_Timer);
startEndButton.setText((CharSequence) app_preferences.getString("timerButton", "Start Timer"));
DatabaseHelper.customerFromDatabaseToList(this);
editor = app_preferences.edit();
editor.commit();
}
public void onDestroy() {
super.onDestroy();
editor.putLong("startTime", startTime);
editor.putString("zeitAnzeige", (String) displayTime.getText());
editor.putString("timerButton", (String) startEndButton.getText());
editor.putLong("endTime", endTime);
editor.putLong("totalTime", totalTime);
editor.putBoolean("running", app_preferences.getBoolean("running", false));
editor.commit();
this.finish();
}
public void onResume() {
super.onResume();
// saveCustomers();
// createDropDown();
}
public void startTimer(View view) {
editor = app_preferences.edit();
if(running == false) {
startTime = getTime();
running = true;
editor.putLong("startTime", startTime);
startEndButton.setText("End Timer");
displayTime.setText("Zeitstoppung läuft");
editor.putString("zeitAnzeige", (String) displayTime.getText());
editor.putString("timerButton", (String) startEndButton.getText());
editor.putBoolean("running", true);
editor.commit();
} else {
setSelectedCustomer();
endTime = getTime();
editor.putLong("endTime",endTime);
totalTime = endTime - startTime;
editor.putLong("totalTime", totalTime);
displayTime.setText(formatTime(totalTime));
editor.putString("zeitAnzeige", (String) displayTime.getText());
startEndButton.setText("Start Timer");
editor.putString("timerButton", (String) startEndButton.getText());
running = false;
editor.putBoolean("running", false);
editor.commit();
DatabaseHelper.timeToDatabase(String.valueOf(selectedCustomer.getId()),formatTime(totalTime),this);
// selectedCustomer.saveTimeToCustomer(selectedCustomer, formatTimeForCustomer(totalTime));
}
}
public String formatTime(Long totalTime) {
int hours = (int) ((totalTime / (1000*60*60)) % 24);
int minutes = (int) ((totalTime / (1000*60)) % 60);
int seconds = (int) (totalTime / 1000) % 60;
String time = (String.valueOf(hours) + ":" + String.valueOf(minutes) + ":" + String.valueOf(seconds));
return time;
}
public String formatTimeForCustomer(Long totalTime) {
StringBuilder time = new StringBuilder();
Calendar cal = Calendar.getInstance();
int year = cal.get(Calendar.YEAR);
int month = cal.get(Calendar.MONTH);
int day = cal.get(Calendar.DAY_OF_MONTH);
time.append((String.valueOf(year) + "." + String.valueOf(month) + "." + String.valueOf(day))).append(formatTime(totalTime));
return time.toString();
}
public void neuerKunde(View view) {
Intent intent = new Intent(this, AddKunde.class);
startActivity(intent);
}
public void kundenÜbersicht(View view) {
// setSelectedCustomer();
Intent intent = new Intent(this, DisplayCustomer.class);
startActivity(intent);
}
public long getTime() {
long millis = System.currentTimeMillis();
return millis;
}
public void setSelectedCustomer() {
if(kunden.size() > 0) {
if (spinner.getSelectedItem().toString() != null) {
String tempCustomer = spinner.getSelectedItem().toString();
for (Kunde k : kunden) {
if (k.getName().equals(tempCustomer)) {
selectedCustomer = k;
}
}
}
}
}
public void createDropDown() {
/*File file = new File(this.getFilesDir(),"kunden.ser"); NOT USED BECAUSE DATABASE WORKS
if(file.exists()) {
Kunde.importFromFile(this);
}*/
if (kunden.size() > 0) {
spinner = (Spinner) findViewById(R.id.chooseCustomer);
// Create an ArrayAdapter using the string array and a default spinner layout
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, DisplayCustomer.namesOfCustomers());
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
spinner.setAdapter(adapter);
}
}
}
DisplayCustomer(Where all customers are displayed with data from Database)
public class DisplayCustomer extends AppCompatActivity {
CustomerAdapter customerAdapter;
public ArrayAdapter<String> adapterCustomerView;
private ListView listCustomerView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_display_customer);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
ArrayList<Kunde> customerList = getCustomerObjects();
customerAdapter = new CustomerAdapter(this,customerList);
listCustomerView = (ListView)findViewById(R.id.list_View_Customers);
// adapterCustomerView = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, namesOfCustomers());
listCustomerView.setAdapter(customerAdapter);
openCustomerDetails();
}
public static ArrayList<String> namesOfCustomers() {
ArrayList<String> customerNames = new ArrayList<>();
if(ZeitErfassen.kunden.size() > 0 ) {
for (Kunde k : ZeitErfassen.kunden) {
customerNames.add(k.getName());
}
}
return customerNames;
}
public static ArrayList<Kunde> getCustomerObjects() {
ArrayList<Kunde> customerList = new ArrayList<>();
if(ZeitErfassen.kunden.size() > 0 ) {
for (Kunde k : ZeitErfassen.kunden) {
customerList.add(k);
}
}
return customerList;
}
public void openCustomerDetails() {
listCustomerView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Kunde kunde = new Kunde();
kunde = (Kunde)listCustomerView.getItemAtPosition(position);
Intent intent = new Intent(DisplayCustomer.this, DisplayDetailedCustomer.class);
intent.putExtra("selectedCustomerObject",(Parcelable)kunde);
startActivity(intent);
}
});
}
}
My CustomerAdapter to pass data from one intent to another.
public class CustomerAdapter extends ArrayAdapter<Kunde> {
public CustomerAdapter(Context context, ArrayList<Kunde> customerList) {
super(context,0,customerList);
}
public View getView(int position, View convertView, ViewGroup parent) {
//Data for this position
Kunde kunde = getItem(position);
if (convertView == null) {
convertView = LayoutInflater.from(getContext()).inflate(R.layout.items_customer_layout, parent, false);
}
// Lookup view for data population
TextView tvName = (TextView) convertView.findViewById(R.id.tvCustomerName);
// Populate the data into the template view using the data object
tvName.setText(kunde.getName());
// Return the completed view to render on screen
return convertView;
}
}
DatabaseHelper Class
public class DatabaseHelper {
public static RequestQueue requestQueue;
public static String host = "http://192.168.150.238/";
public static final String insertUrl = host+"insertCustomer.php";
public static final String showUrl = host+"showCustomer.php";
public static final String insertTimeUrl = host+"insertTime.php";
public static final String showTimeUrl = host+"showTimes.php";
public static void customerFromDatabaseToList(final Context context) {
//Display customer from database
requestQueue = Volley.newRequestQueue(context);
final ArrayList<String> customerNames = new ArrayList<>();
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.POST, showUrl, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
JSONArray customers = response.getJSONArray("customers");
if(customers.length() > 0) {
for (int i = 0; i < customers.length(); i++) {
JSONObject customer = customers.getJSONObject(i);
String customerName = customer.getString("cus_name");
String customerAddress = customer.getString("cus_address");
int customerID = Integer.valueOf(customer.getString("cus_id"));
if (customerName != null && customerAddress != null) {
try {
Kunde k = new Kunde(customerName, customerAddress, customerID);
if (!listContainsObject(k)) {
ZeitErfassen.kunden.add(k);
}
} catch (Exception e) {
showAlert("Fehler in customerFromDatabaseToListn!", "Fehler", context);
}
} else {
showAlert("Fehler in customerFromDatabaseToListn!", "Fehler", context);
}
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
requestQueue.add(jsonObjectRequest);
}
public static boolean listContainsObject(Kunde cust) {
for(Kunde k : ZeitErfassen.kunden) {
if(k.getId() == cust.getId()) {
return true;
}
}
return false;
}
public static void timeToDatabase(final String customer_id, final String time_value, final Context context) {
requestQueue = Volley.newRequestQueue(context);
StringRequest request = new StringRequest(Request.Method.POST, DatabaseHelper.insertTimeUrl, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
showAlert("Fehler","Fehler bei Verbindung zur Datenbank",context);
}
}) {
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String,String> parameters = new HashMap<String,String>();
parameters.put("customerid",customer_id);
parameters.put("timevalue",time_value);
return parameters;
}
};
requestQueue.add(request);
};
public static void showAlert(String title, String message, Context context) {
// 1. Instantiate an AlertDialog.Builder with its constructor
AlertDialog.Builder builder = new AlertDialog.Builder(context);
// 2. Chain together various setter methods to set the dialog characteristics
builder.setMessage(message)
.setTitle(title);
// 3. Get the AlertDialog from create()
AlertDialog dialog = builder.create();
}
public static ArrayList<String> timesFromDataBaseToList(final Context context,final int customer_id) {
requestQueue = Volley.newRequestQueue(context);
final String cus_id = String.valueOf(customer_id) ;
final ArrayList<String> customerTimes = new ArrayList<>();
StringRequest jsonObjectRequest = new StringRequest(Request.Method.POST, showTimeUrl, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject object = new JSONObject(response.toString());
JSONArray times = object.getJSONArray("customertimes");
if (times.length() > 0) {
for (int i = 0; i < times.length(); i++) {
JSONObject jsonObject = times.getJSONObject(i);
String timeValue = jsonObject.getString("time_value");
if (timeValue != null) {
customerTimes.add(timeValue);
}
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(context,"Fehler beim Holen der Zeiten",Toast.LENGTH_LONG).show();
error.printStackTrace();
}
}){
protected Map<String, String> getParams() throws AuthFailureError {
Map<String,String> parameters = new HashMap<String,String>();
parameters.put("cus_id",cus_id);
return parameters;
}
};
requestQueue.add(jsonObjectRequest);
return customerTimes;
};
}
DisplayDetailedCustomer / Display the times
public class DisplayDetailedCustomer extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_display_detailed_customer);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
Intent getCustomerParcable = getIntent();
Kunde customer = getCustomerParcable.getExtras().getParcelable("selectedCustomerObject");
TextView displayCustomerNameDetailed =(TextView) findViewById(R.id.detailedCustomerViewName);
TextView displayCustomerAddressDetailed =(TextView) findViewById(R.id.detailedCustomerAddress);
ListView timeListView = (ListView)findViewById(R.id.detailedTimeListView);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, DatabaseHelper.timesFromDataBaseToList(this,customer.getId()));
timeListView.setAdapter(adapter);
displayCustomerNameDetailed.setText(customer.getName());
displayCustomerAddressDetailed.setText(customer.getAdresse());
}
}
Kunde Class / Customer Class with interface Parcelable
public class Kunde implements Serializable,Parcelable {
private String name;
private String adresse;
private int id;
public LinkedList<String> zeiten;
public Kunde(String name, String adresse) throws Exception{
setName(name);
setAdresse(adresse);
zeiten = new LinkedList<String>();
}
public Kunde(String name, String adresse,int id) throws Exception{
setName(name);
setAdresse(adresse);
setId(id);
zeiten = new LinkedList<String>();
}
public Kunde(){};
public void setId(int id) {
this.id = id;
}
public int getId(){
return id;
}
public void setName(String name) throws Exception {
if(name != null) {
this.name = name;
} else throw new Exception("Name ist ungueltig! in setName");
}
public void setAdresse(String adresse) throws Exception{
if(adresse != null) {
this.adresse = adresse;
}else throw new Exception("Adresse ist ungueltig! in setAdresse");
}
public String getName() {
return name;
}
public String getAdresse() {
return adresse;
}
public void saveZeit(Long totalTime) {
zeiten.add(String.valueOf(totalTime));
}
public void saveTimeToCustomer(Kunde customer,String time){
customer.zeiten.add(time);
}
//------------------------------------Parcelable Methods to pass Daata from one Intent to another----------------------------------------
#Override
public int describeContents() {
return 0;
}
#Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeInt(this.id);
dest.writeString(this.name);
dest.writeString(this.adresse);
// dest.writeList(this.zeiten);
}
// this is used to regenerate your object. All Parcelables must have a CREATOR that implements these two methods
public static final Parcelable.Creator<Kunde> CREATOR = new Parcelable.Creator<Kunde>() {
public Kunde createFromParcel(Parcel in) {
return new Kunde(in);
}
public Kunde[] newArray(int size) {
return new Kunde[size];
}
};
// example constructor that takes a Parcel and gives you an object populated with it's values
private Kunde(Parcel in) {
LinkedList<String> zeiten = null;
id = in.readInt();
name = in.readString();
adresse = in.readString();
}
}
Thanks for taking your time!!

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