Develop Reference

Mimic the back button on the actionbar

So I have the action bar back button which returns me from an activity to my main activity. The problem I have is that it calls loadData() (which loads data from an API) when you press the action bar back button.
If I press the back button on the device (the button beside the home button) then I will be brought back to the previous view (the mainactivity) and won't have to call the API again.
So I'm trying to find a way to mimic the physical back button as an action bar widget.
I don't want MainActivity's code to be called again as it will execute another API call (I can only have 5 per minute) and it is also slower. I just want it to go back to the view I was just at.
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerView;
private RecyclerView.Adapter adapter;
private ArrayList<ListItem> listItems;
private String defaultQuery = "ham";
private String builtURL;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
recyclerView = findViewById(R.id.recycler_view);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
listItems = new ArrayList<>();
loadData(defaultQuery);
}
#Override
public boolean onCreateOptionsMenu(final Menu menu) {
getMenuInflater().inflate(R.menu.menu_main, menu);
final SearchView searchView = (SearchView) menu.findItem(R.id.action_search).getActionView();
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String query) {
listItems.clear();
loadData(query);
(menu.findItem(R.id.action_search)).collapseActionView();
return false;
}
#Override
public boolean onQueryTextChange(String newText) {
return false;
}
});
searchView.setIconified(false);
return true;
}
public void loadData(String query) {
final ProgressDialog progressDialog = new ProgressDialog(this);
progressDialog.setMessage("Loading recipes...");
progressDialog.show();
Log.d("q", "loadData: " + query);
builtURL = buildURL(query);
StringRequest request = new StringRequest(Request.Method.GET,
builtURL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
progressDialog.dismiss();
if(response == null) {
response = "THERE WAS AN ERROR";
}
try {
JSONObject obj = new JSONObject(response);
JSONArray hits = obj.getJSONArray("hits");
for (int i = 0; i < hits.length(); i++) {
JSONObject a = hits.getJSONObject(i);
JSONObject recipe = a.getJSONObject("recipe");
String ingredients = recipe.getString("ingredientLines");
ingredients = ingredients.replace("[", "");
ingredients = ingredients.replace("]", "");
ingredients = ingredients.replace("\"", "");
ingredients = ingredients.replace("\\", "");
ingredients = ingredients.replace(",", "\n");
ListItem item = new ListItem(
recipe.getString("label"),
recipe.getString("source"),
recipe.getString("image"),
ingredients,
recipe.getString("url")
);
listItems.add(item);
}
adapter = new Adapter(listItems, getApplicationContext(), builtURL);
recyclerView.setAdapter(adapter);
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
progressDialog.dismiss();
Toast.makeText(getApplicationContext(), error.getMessage(), Toast.LENGTH_LONG).show();
}
});
RequestQueue rq = Volley.newRequestQueue(this);
rq.add(request);
}
private String buildURL(String query) {
Log.d("q", "buildURL: " + query);
Uri.Builder builder = new Uri.Builder();
//url built here but I removed it because it shows API key etc.
String urlToSend = builder.build().toString();
//debugging purposes to show the url created
Log.d("url", "doInBackground: " + urlToSend);
return urlToSend;
}
#Override
public boolean onNavigateUp(){
finish();
return true;
}
This is the activity that I'm coming from.
public class recipe_view extends AppCompatActivity {
ImageView ivRecipeImage;
TextView tvRecipeName;
TextView tvRecipeCreator;
TextView tvRecipeIngredients;
String url;
Integer pos;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_recipe_view);
Bundle data = getIntent().getExtras();
ArrayList<ListItem> list = data.getParcelableArrayList("list");
pos = data.getInt("pos");
for (int i = 0; i < list.size() ; i++) {
System.out.println(list.get(i));
System.out.println(pos);
}
ivRecipeImage = findViewById(R.id.recipeImage);
tvRecipeName = findViewById(R.id.recipeName);
tvRecipeCreator = findViewById(R.id.recipeCreator);
tvRecipeIngredients = findViewById(R.id.ingredients);
tvRecipeName.setText(list.get(pos).getTitle());
tvRecipeCreator.setText(list.get(pos).getAuthor());
Picasso.with(getApplicationContext())
.load(list.get(pos).getImageUrl())
.centerCrop()
.fit()
.into(ivRecipeImage);
tvRecipeIngredients.setText(list.get(pos).getListOfIngredients());
url = list.get(pos).getRecipeUrl();
final Button button = findViewById(R.id.bViewInstructions);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent goToBrowser = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(goToBrowser);
}
});
}
}

In your manifest xml
set
<activity
android:name=".your_activity"
android:label="#string/title_activity_sign_up"
android:parentActivityName=".whateveractivity"
android:screenOrientation="portrait" >
</activity>
then in code
#Override
public void onBackPressed() {
NavUtils.navigateUpFromSameTask(this);
// Otherwise defer to system default behavior.
super.onBackPressed();
}
To elaborate what you are doing is overriding the onbackpressed hardware button.
Also make your parent activity's launchmode singleInstance.

button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent goToBrowser = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(goToBrowser);
finish();
}
});

when press back button activity does not finish

My app contains two activities and First activity load data from web using volley and after successful loading of data start second activity, the second activity contains dynamic tabs and view pager. My issues is when i press back button from second activity does not finish the activity but restart second activity again and it will finish when press ten times of back button that is my tabs count is 10, any one can help me to solve this issue..
First Actvity, SplashActivity.java
public class SplashActivity extends AppCompatActivity {
private static final String HOME_URL = "http://sampleurl.com/beta/Mobile_controller";
public static ArrayList<CategoryModel> categories;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_splash);
getCategories();
}
private void getCategories() {
categories = new ArrayList<>();
StringRequest request = new StringRequest(Request.Method.POST, HOME_URL, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject object = new JSONObject(response);
JSONArray categoryJsonArray = object.getJSONArray("category");
for (int i = 0; i < categoryJsonArray.length(); i++) {
CategoryModel model = new CategoryModel();
JSONObject cat = categoryJsonArray.getJSONObject(i);
model.setCategoryID(cat.getString("category_id"));
model.setCategoryName(cat.getString("category_name"));
categories.add(model);
startActivity(new Intent(getApplicationContext(), MainActivity.class));
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getApplicationContext(), String.valueOf("error : " + error.getMessage()),Toast.LENGTH_SHORT).show();
}
});
RequestQueue queue = Volley.newRequestQueue(SplashActivity.this);
queue.add(request);
}
}
Second Activity MainActivity.java
public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
MediaController mediaController;
private ArrayList<CategoryModel> categoryList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.tb_home);
setSupportActionBar(toolbar);
categoryList = SplashActivity.categories;
NavigationView navDrawer = (NavigationView) findViewById(R.id.navigation_home);
navDrawer.setNavigationItemSelectedListener(this);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout_home);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.app_name, R.string.app_name);
drawer.setDrawerListener(toggle);
toggle.syncState();
TabLayout tabLayout = (TabLayout) findViewById(R.id.tbl_home);
for (int i = 0; i < categoryList.size(); i++) {
tabLayout.addTab(tabLayout.newTab().setText(categoryList.get(i).getCategoryName()));
}
final ViewPager viewPager = (ViewPager) findViewById(R.id.vp_home_content);
SwipingTabsAdapter swipingTabsAdapter = new SwipingTabsAdapter(getSupportFragmentManager(), categoryList, tabLayout.getTabCount());
viewPager.setAdapter(swipingTabsAdapter);
viewPager.setOffscreenPageLimit(3);
viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
#Override
public void onTabSelected(TabLayout.Tab tab) {
viewPager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(TabLayout.Tab tab) {
}
#Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_option_home, menu);
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
SearchView searchView = (SearchView) menu.findItem(R.id.menu_option_search).getActionView();
if (searchView != null) {
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String query) {
return false;
}
#Override
public boolean onQueryTextChange(String newText) {
Toast.makeText(getApplicationContext(), newText, Toast.LENGTH_SHORT).show();
return true;
}
});
}
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.menu_option_account:
Toast.makeText(getApplicationContext(), "account", Toast.LENGTH_SHORT).show();
break;
}
return true;
}
#Override
public void onBackPressed() {
super.onBackPressed();
}
#Override
public boolean onNavigationItemSelected(#NonNull MenuItem item) {
return false;
}
}
View pager Adapter
public class SwipingTabsAdapter extends FragmentStatePagerAdapter {
private int tabs;
private ArrayList<CategoryModel> categoryList;
public SwipingTabsAdapter(FragmentManager fm, ArrayList<CategoryModel> categories, int tabCounts) {
super(fm);
this.categoryList = categories;
this.tabs = tabCounts;
}
#Override
public Fragment getItem(int position) {
/*switch (position) {
case 0:
return new NewsCategoriesFragment();
case 1:
return new NewsCategoriesFragment();
default:
return new NewsCategoriesFragment();
}*/
return NewsCategoriesFragment.newInstance(Integer.parseInt(categoryList.get(position).getCategoryID()));
}
#Override
public int getCount() {
return tabs;
}
}
My fragment
public class NewsCategoriesFragment extends Fragment {
private ArrayList<SliderModel> sliderNews;
private SliderNewsAdapter sliderNewsAdapter;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_new_categories, container, false);
Button button = (Button) view.findViewById(R.id.button);
Bundle bundle = getArguments();
int id = bundle.getInt("id");
getNews(id);
ViewPager viewPager = (ViewPager) view.findViewById(R.id.vp_slider_news);
sliderNewsAdapter = new SliderNewsAdapter(getContext(), sliderNews);
viewPager.setAdapter(sliderNewsAdapter);
button.setText(String.valueOf(id));
return view;
}
public static Fragment newInstance(int id) {
NewsCategoriesFragment fragment = new NewsCategoriesFragment();
Bundle bundle = new Bundle();
bundle.putInt("id", id);
fragment.setArguments(bundle);
return fragment;
}
private void getNews(final int categoryId) {
sliderNews = new ArrayList<>();
StringRequest request = new StringRequest(Request.Method.POST, NEWS_URL, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONObject object = new JSONObject(response);
JSONArray sliderNewsJsonArray = object.getJSONArray("slider_news");
for (int i = 0; i < sliderNewsJsonArray.length(); i++) {
SliderModel model = new SliderModel();
JSONObject data = sliderNewsJsonArray.getJSONObject(i);
model.setNewsThumbImg(data.getString("news_thump_image"));
sliderNews.add(model);
}
sliderNewsAdapter.notifyDataSetChanged();
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getContext(), "JSON Exception", Toast.LENGTH_SHORT).show();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getContext(), String.valueOf("error "+ error.getMessage()), Toast.LENGTH_SHORT).show();
}
}){
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> data = new HashMap<>();
data.put("id", String.valueOf(categoryId));
return data;
}
};
RequestQueue queue = Volley.newRequestQueue(getContext());
queue.add(request);
}
}

Problem is you put your startActivity inside the for loop, put start activity after for loop in Splashactiivty getCategories, it will work fine
Change this,
try {
JSONObject object = new JSONObject(response);
JSONArray categoryJsonArray = object.getJSONArray("category");
for (int i = 0; i < categoryJsonArray.length(); i++) {
CategoryModel model = new CategoryModel();
JSONObject cat = categoryJsonArray.getJSONObject(i);
model.setCategoryID(cat.getString("category_id"));
model.setCategoryName(cat.getString("category_name"));
categories.add(model);
startActivity(new Intent(getApplicationContext(), MainActivity.class));
}
} catch (JSONException e) {
e.printStackTrace();
}
to
try {
JSONObject object = new JSONObject(response);
JSONArray categoryJsonArray = object.getJSONArray("category");
for (int i = 0; i < categoryJsonArray.length(); i++) {
CategoryModel model = new CategoryModel();
JSONObject cat = categoryJsonArray.getJSONObject(i);
model.setCategoryID(cat.getString("category_id"));
model.setCategoryName(cat.getString("category_name"));
categories.add(model);
}
startActivity(new Intent(getApplicationContext(), MainActivity.class));
} catch (JSONException e) {
e.printStackTrace();
}

in second activity override as
#Override
public void onBackPressed() {
finish();
}

You don't really need to Launch a intent to previous activity. Android has something called Back Stack which contains previous launched activities in a stack data structure.You could have just overridden onBackPressed() method to get it done.
#Override
public void onBackPressed(){
this.finish();
}
Also note launching intent as NewTask helps you to get away from existing backstack and has its own backstack.

Multiple Service calling by using Volley

I have a MainActivity where the Swipeable Tabs are created and from there two fragments are called. I have 2 webservice for Fragment A and Fragment B where I have to parse data coming from server. I am using volley. When I am in the first fragment; both the webservice are being called and the data are not loaded for the first time.
But in the Second time it is showing correctly but it should be like this that when I am in Fragment A the service of the Fragment A should be called and when I am in Fragment B the service of the Fragment B should be called. I am attaching the code snippets.
MainActivity.java
public class MainActivity extends AppCompatActivity {
DrawerLayout mDrawerLayout;
NavigationView mNavigationView;
FragmentManager mFragmentManager;
FragmentTransaction mFragmentTransaction;
int status = 0 ;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/**
*Setup the DrawerLayout and NavigationView
*/
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawerLayout);
mNavigationView = (NavigationView) findViewById(R.id.shitstuff);
android.support.v7.widget.Toolbar toolbar = (android.support.v7.widget.Toolbar) findViewById(R.id.toolbar);
// Show menu icon
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayShowHomeEnabled(true);
/**
* Lets inflate the very first fragment
* Here , we are inflating the NewsFragment as the first Fragment
*/
mFragmentManager = getSupportFragmentManager();
mFragmentTransaction = mFragmentManager.beginTransaction();
mFragmentTransaction.replace(R.id.containerView, new NewsFragment()).commit();
// mNavigationView.setBackgroundColor(Color.parseColor("#CFCFCF"));
/**
* Setup click events on the Navigation View Items.
*/
mNavigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
mDrawerLayout.closeDrawers();
if (menuItem.getItemId() == R.id.nav_item_sent) {
FragmentTransaction fragmentTransaction = mFragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.containerView, new SportsFragment()).commit();
status = 1;
if (status == 1){
}
}
if (menuItem.getItemId() == R.id.nav_item_inbox) {
FragmentTransaction xfragmentTransaction = mFragmentManager.beginTransaction();
xfragmentTransaction.replace(R.id.containerView, new NewsFragment()).commit();
}
if (menuItem.getItemId() == R.id.nav_item_sent){
FragmentTransaction xfragmentTransaction = mFragmentManager.beginTransaction();
xfragmentTransaction.replace(R.id.containerView, new VideosFragment()).commit();
}
if (menuItem.getItemId() == R.id.nav_item_draft) {
FragmentTransaction xfragmentTransaction = mFragmentManager.beginTransaction();
xfragmentTransaction.replace(R.id.containerView, new OpinionFragment()).commit();
}
if (menuItem.getItemId() == R.id.nav_item_sports) {
FragmentTransaction xfragmentTransaction = mFragmentManager.beginTransaction();
xfragmentTransaction.replace(R.id.containerView, new SportsFragment()).commit();
}
if (menuItem.getItemId() == R.id.nav_item_weather) {
FragmentTransaction xfragmentTransaction = mFragmentManager.beginTransaction();
xfragmentTransaction.replace(R.id.containerView, new NewsFragment()).commit();
}
return false;
}
});
/**
* Setup Drawer Toggle of the Toolbar
*/
ActionBarDrawerToggle mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout, toolbar, R.string.app_name,
R.string.app_name);
mDrawerLayout.setDrawerListener(mDrawerToggle);
mDrawerToggle.syncState();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_about_us:
Intent intent = new Intent(MainActivity.this, AboutUs.class);
startActivity(intent);
return true;
case R.id.action_terms_of_use:
Intent intent_two = new Intent(MainActivity.this, TermsUse.class);
startActivity(intent_two);
return true;
case R.id.action_privacy_policy:
Intent intent_three = new Intent(MainActivity.this, PrivacyPolicy.class);
startActivity(intent_three);
return true;
case R.id.action_contact_us:
Intent intent_four = new Intent(MainActivity.this, ContactUs.class);
startActivity(intent_four);
case R.id.search:
// hidetext();
Toast.makeText(MainActivity.this, "In the development Phase... Thank You...", Toast.LENGTH_SHORT).show();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
// private void hidetext() {
//
// Intent i = new Intent(MainActivity.this, SearchResultActivity.class);
// startActivity(i);
// }
}
TopNewsFragment
public class TopNewsFragment extends Fragment {
// Log tag
private static final String TAG = MainActivity.class.getSimpleName();
private static final String url = "http://sikkimexpress.itstunner.com/api/homenewslist/topnews";
private ProgressDialog pDialog;
private List<Movie> movieList = new ArrayList<Movie>();
Movie movie;
private ListView listView;
private CustomListAdapter adapter;
String imageURL = "", title = "", description = "";
public static final String KEY_ID = "news_id";
public static final String KEY_HEADURL = "news_url";
public static final String KEY_DETAILS = "news_details";
public static final String KEY_TITLE = "news_title";
RequestQueue requestQueue;
public TopNewsFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View rootView = inflater.inflate(R.layout.fragment_news, container, false);
listView = (ListView) rootView.findViewById(R.id.list);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int Position,
long offset) {
// TODO Auto-generated method stub
Movie item = (Movie) adapter.getItem(Position);
Intent intent = new Intent(rootView.getContext(), DetailsPage.class);
intent.putExtra(KEY_ID, item.getNewsId());
intent.putExtra(KEY_HEADURL, item.getThumbnailUrl());
intent.putExtra(KEY_TITLE, item.getTitle());
intent.putExtra(KEY_DETAILS, item.getDescription());
startActivity(intent);
}
});
// requestQueue = Volley.newRequestQueue(getActivity());
adapter = new CustomListAdapter(getActivity(), movieList);
listView.setAdapter(adapter);
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Loading...Please Wait...");
pDialog.setCancelable(false);
pDialog.show();
Volley.newRequestQueue(getActivity()).add(new JsonObjectRequest(Request.Method.GET, url, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
hidePDialog();
try {
JSONArray jsonArray = response.getJSONArray("HomeNews");
// if (jsonArray.length() == 0) {
// new AlertDialog.Builder(getActivity())
// .setTitle("Alert")
// .setMessage("No Items found...")
// .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
// public void onClick(DialogInterface dialog, int which) {
// // continue with delete
// }
// })
// .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
// public void onClick(DialogInterface dialog, int which) {
// // do nothing
// }
// })
// .setIcon(android.R.drawable.ic_dialog_alert)
// .show();
// }
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject homenews = jsonArray.getJSONObject(i);
Movie movie = new Movie();
movie.setNewsId(homenews.getString("NewsId"));
movie.setDateTime(homenews.getString("DateTime"));
movie.setNewsType(homenews.getString("NewsType"));
movie.setTitle(homenews.getString("Title"));
title = movie.setTitle(homenews.getString("Title"));
description = movie.setDescription(homenews.getString("Description"));
movie.setDescription(homenews.getString("Description"));
imageURL = movie.setThumbnailUrl(homenews.getString("MainImageThumbnail"));
movie.setThumbnailUrl(homenews.getString("MainImageThumbnail"));
movieList.add(movie);
System.out.println("Setting up in ListView");
// System.out.println("Result:- " + newsId + " " + dateTime + " " + newsType + " " + title + " " + description + " " + mainImageURL);
}
} catch (JSONException e) {
e.printStackTrace();
}
adapter.notifyDataSetChanged();
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
// new AlertDialog.Builder(getActivity())
// .setTitle("No Connectivity ")
// .setMessage("Please check your internet connectivity!")
// .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
// public void onClick(DialogInterface dialog, int which) {
// // continue with delete
// }
// })
// //.setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
// //public void onClick(DialogInterface dialog, int which) {
// // do nothing
// //}
// //})
// .setIcon(android.R.drawable.ic_dialog_alert)
// .show();
hidePDialog();
}
}));
// AppController.getInstance().addToRequestQueue(jsonObjectRequest);
// requestQueue.add(jsonObjectRequest);
return rootView;
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
}
#Override
public void onDetach() {
super.onDetach();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
}
LatestNewsFragment.java
public class LatestNewsFragment extends Fragment {
// Log tag
private static final String TAG = MainActivity.class.getSimpleName();
private static final String url = "http://sikkimexpress.itstunner.com/api/homenewslist/latest";
private ProgressDialog pDialog;
private List<Movie> movieList = new ArrayList<Movie>();
private ListView listView;
private CustomListAdapter adapter;
// contacts JSONArray
private JSONArray users = null;
RequestQueue requestQueue;
public static final String KEY_HEADURL="news_url";
public static final String KEY_DETAILS="news_details";
public static final String KEY_TITLE = "news_title";
public LatestNewsFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View rootView = inflater.inflate(R.layout.fragment_news, container, false);
listView = (ListView) rootView.findViewById(R.id.list);
// requestQueue = Volley.newRequestQueue(getActivity());
adapter = new CustomListAdapter(getActivity(), movieList);
listView.setAdapter(adapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int Position,
long offset) {
// TODO Auto-generated method stub
Movie item = (Movie) adapter.getItem(Position);
Intent intent = new Intent(rootView.getContext(), DetailsPage.class);
// intent.putExtra("URL", movie.getThumbnailUrl());
// intent.putExtra("title", movie.getTitle());
// intent.putExtra("description", movie.getDescription());
intent.putExtra(KEY_HEADURL, item.getThumbnailUrl());
intent.putExtra(KEY_TITLE, item.getTitle());
intent.putExtra(KEY_DETAILS, item.getDescription());
startActivity(intent);
}
});
pDialog = new ProgressDialog(getActivity());
// Showing progress dialog before making http request
pDialog.setMessage("Loading...Please Wait...");
pDialog.setCancelable(false);
pDialog.show();
Volley.newRequestQueue(getActivity()).add(new JsonObjectRequest(Request.Method.GET, url, new Response.Listener<JSONObject>() {
// JsonObjectRequest jsonObjectRequest =
#Override
public void onResponse(JSONObject response) {
try {
hidePDialog();
JSONArray jsonArray = response.getJSONArray("HomeNews");
// if (jsonArray.length() == 0){
// new AlertDialog.Builder(getActivity())
// .setTitle("Alert")
// .setMessage("No Items found...")
// .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
// public void onClick(DialogInterface dialog, int which) {
// // continue with delete
// }
// })
// .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
// public void onClick(DialogInterface dialog, int which) {
// // do nothing
// }
// })
// .setIcon(android.R.drawable.ic_dialog_alert)
// .show();
// }
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject homenews = jsonArray.getJSONObject(i);
Movie movie = new Movie();
movie.setNewsId(homenews.getString("NewsId"));
movie.setDateTime(homenews.getString("DateTime"));
movie.setNewsType(homenews.getString("NewsType"));
movie.setTitle(homenews.getString("Title"));
movie.setDescription(homenews.getString("Description"));
movie.setThumbnailUrl(homenews.getString("MainImageThumbnail"));
movieList.add(movie);
System.out.println("Setting up in ListView");
}
} catch (JSONException e) {
e.printStackTrace();
}
adapter.notifyDataSetChanged();
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
// new AlertDialog.Builder(getActivity())
// .setTitle("No Connectivity ")
// .setMessage("Please check your internet connectivity!")
// .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
// public void onClick(DialogInterface dialog, int which) {
// // continue with delete
// }
// })
// //.setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
// //public void onClick(DialogInterface dialog, int which) {
// // do nothing
// //}
// //})
// .setIcon(android.R.drawable.ic_dialog_alert)
// .show();
hidePDialog();
}
}));
// AppController.getInstance().addToRequestQueue(jsonObjectRequest);
// requestQueue.add(jsonObjectRequest);
return rootView;
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
}
#Override
public void onDetach() {
super.onDetach();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
}

What probably happens is that the two fragments are both loaded even though you are only looking at one fragment at a time. Instead of creating a new RequestQueue on every request you should only have one. For example create an Application class like so:
public class MyApp extends Application {
private RequestQueue mRequestQueue;
private static MyApp mInstance;
#Override
public void onCreate() {
super.onCreate();
mInstance = this;
}
public static synchronized MyApp getInstance() {
return mInstance;
}
public RequestQueue getRequestQueue() {
if (mRequestQueue == null) {
mRequestQueue = Volley.newRequestQueue(getApplicationContext());
}
return mRequestQueue;
}
public <T> void addToRequestQueue(Request<T> req) {
req.setTag(TAG);
getRequestQueue().add(req);
}
}
Don't forget to add your application class to your manifest inside the <activity> tag:
<application
android:name=".MyApp"
Now you can put requests on that queue from your fragments:
JsonObjectRequest req = new JsonObjectRequest(Request.Method.GET,
URL, null, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
//Do something with response
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
//Do something with error
}
});
//Put the actual request on the queue
MyApp.getInstance().addToRequestQueue(req);

Row selection ListView Android

my question is how can i do something when the user touches a row on the ListView
My app loads a json file and parses it using the Volley Library then everything is loaded nicely on a custom list row
But when I hit a row it does nothing
Really annoying thing ...
Im using a custom view and it has been impossible to assign the OnListItemClick
Here is my code
//all necessary libraries here
public class InicioPasajero extends Activity {
private static final String TAG = InicioPasajero.class.getSimpleName();
// Movies json url
private static final String url = "URL_RETURNING_JSON";
private ProgressDialog pDialog;
private List<Movie> movieList = new ArrayList<Movie>();
private ListView listView;
private CustomListAdapter adapter;
ImageButton b_ajustes;
ImageButton b_filtros;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_inicio_pasajero);
b_ajustes= (ImageButton) findViewById(R.id.Bajustes);
b_filtros= (ImageButton) findViewById(R.id.Bfiltros);
b_ajustes.setOnClickListener(new View.OnClickListener(){
public void onClick(View view){
Intent a=new Intent(InicioPasajero.this, MiPerfil.class);
startActivity(a);
}
});
listView = (ListView) findViewById(R.id.list);
adapter = new CustomListAdapter(this, movieList);
listView.setAdapter(adapter);
pDialog = new ProgressDialog(this);
// Showing progress dialog before making http request
pDialog.setMessage("Cargando...");
pDialog.show();
// changing action bar color
// Creating volley request obj
JsonArrayRequest movieReq = new JsonArrayRequest(url,
new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
Log.d(TAG, response.toString());
hidePDialog();
// Parsing json
for (int i = 0; i < response.length(); i++) {
try {
JSONObject obj = response.getJSONObject(i);
Movie movie = new Movie();
movie.setTitle(obj.getString("n"));
movie.setThumbnailUrl(obj.getString("i"));
movie.setRating(obj.getString("r"));
movie.setYear(obj.getString("h"));
// Genre is json array
JSONArray genreArry = obj.getJSONArray("g");
ArrayList<String> genre = new ArrayList<String>();
for (int j = 0; j < genreArry.length(); j++) {
genre.add((String) genreArry.get(j));
}
movie.setGenre(genre);
// adding movie to movies array
movieList.add(movie);
} catch (JSONException e) {
e.printStackTrace();
}
}
// notifying list adapter about data changes
// so that it renders the list view with updated data
adapter.notifyDataSetChanged();
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d(TAG, "Error: " + error.getMessage());
hidePDialog();
}
});
// Adding request to request queue
AppController.getInstance().addToRequestQueue(movieReq);
}
protected void onListItemClick(ListView movieList, View view, int posicion, long id) {
Log.i("Sel:","si");
// Hacer algo cuando un elemento de la lista es seleccionado
TextView textoTitulo = (TextView) view.findViewById(R.id.title);
CharSequence texto = "Seleccionado: " + textoTitulo.getText();
Toast.makeText(getApplicationContext(), texto, Toast.LENGTH_LONG).show();
}
#Override
public void onDestroy() {
super.onDestroy();
hidePDialog();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
/*
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}*/
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) {
// no hacemos nada.
return true;
}
return super.onKeyDown(keyCode, event);
}
}
Thanks in advance.

I don't see you calling setOnItemClickListener on your ListView anywhere? It also looks like you meant to have the Activity implement AdapterView.OnItemClickListener - then the overridden method named onItemClick would get called when a list item is clicked.

Passing data from activity to swipeable view fragment

Ok, I'm new to android programming and here is my problem. I've got an async task that collects json data from a server on a httpget request and updates a listview fragment in a swipeable view. I want a way to send data(a bunch of strings) from the main TabActivity class to the Tab1Fragment class.
I've done my level best at stripping down the code to the essentials.
NOTE: I've tried the bundle method that I've read in other similar questions, but they all end up throwing NULL pointer exceptions in the fragment, meaning the bundle isn't getting sent.(?)
This is my main Tab Activity:
TabActivity.java
public class TabActivity extends ActionBarActivity implements ActionBar.TabListener {
private String phoneno;
private static String url = "http://my/url/forjson";
//JSON Node Names
private static final String TAG_OPERATOR = "operator";
private static final String TAG_REGNO = "Reg No";
public String operator;
public String regNo;
private ViewPager viewPager;
private TabsPagerAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = { "Details", "Others"};
Bundle bundle = new Bundle();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_tab);
Intent intent = getIntent();
phoneno = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
new JSONParse().execute();
viewPager = (ViewPager) findViewById(R.id.pager);
actionBar = getSupportActionBar();
mAdapter = new TabsPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(mAdapter);
actionBar.setHomeButtonEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Adding Tabs
for (String tab_name : tabs) {
actionBar.addTab(actionBar.newTab().setText(tab_name)
.setTabListener(this));
}
/**
* on swiping the viewpager make respective tab selected
* */
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageSelected(int position) {
// on changing the page
// make respected tab selected
actionBar.setSelectedNavigationItem(position);
}
#Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
#Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
#Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
#Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
// on tab selected
// show respected fragment view
viewPager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
}
/*Private Class to parse JSON*/
private class JSONParse extends AsyncTask<String, String, JSONObject> {
private ProgressDialog pDialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(TabActivity.this);
pDialog.setMessage("Getting Data ...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
#SuppressWarnings("finally")
#Override
protected JSONObject doInBackground(String... args) {
//*
JSONParser jParser = new JSONParser();
// Getting JSON from URL
StringBuilder finalUrl = new StringBuilder();
JSONObject jsonForData = new JSONObject();
try{
finalUrl.append(url);
jsonForData = jParser.getJSONFromUrl(finalUrl.toString());
}catch (JSONException e) {
e.printStackTrace();
}
return jsonForData;
}
#Override
protected void onPostExecute(JSONObject json) {
pDialog.dismiss();
try {
Bundle bundle=new Bundle();
bundle.putString("oper", json.getString(TAG_OPERATOR));
bundle.putString("regNo", json.getString(TAG_REGNO));
mAdapter.getData(bundle);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}
In the above code, please understand that the JSONPasrser class that I've instantiated returns a JSONObject from the url and it works. So, no issues there.
Further, my fragment class is a listview as follows:
Tab1Fragment.java
public class Tab1Fragment extends ListFragment{
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_tab1, container, false);
String abc = "No Details Presently Available";
//Fill all string values with something
String[] values = new String[2];
for(int i=0;i<values.length;i++)
values[i] = " ";
//Make Sure number of elements match
try{
values[0] = "Provider: " + getArguments().getString("oper");//Gives a NULL value
values[1] = "No: " + + getArguments().getString("regNo");//Gives a NULL value
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this.getActivity(), android.R.layout.simple_list_item_1,values);
// Assign adapter to ListView
setListAdapter(adapter);
}
catch(Exception e){
e.printStackTrace();
Log.w("Error","The App didn't have enough elements specified to populate the listview");
}
return rootView;
}
}
The "abc" string that I've hardcoded should ideally have details sent from the TabActivity class.
I want the above fragment to recieve data from the TabActivity class to populate the listview. Any help is appreciated :)
EDIT: I've changed the adapter class as follows based on Illegal Argument's suggestion.
So now, the bundle is passed as TabActivity->TabsPagerAdapter->Tab1Fragment
But still, NULL value returned.
My Adapter class is now as follows:
TabsPagerAdapter.java
public class TabsPagerAdapter extends FragmentStatePagerAdapter {
Bundle bundle = new Bundle();
public TabsPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int index) {
switch (index) {
case 0:
Fragment fragment = new Tab1Fragment();
this.bundle.putString("operator", "hi");
fragment.setArguments(this.bundle);
return fragment;
case 1:
return new Tab2Fragment();
}
return null;
}
#Override
public int getCount() {
// get item count - equal to number of tabs
return 2;
}
public void getData(Bundle bundle){
this.bundle = bundle;
}
}

I can see that you have successfully passed data via a bundle. Please remove this. from your code below:
this.bundle.putString("operator", "hi");
fragment.setArguments(this.bundle);
change it because it is not required to be accessed that way:
bundle.putString("operator", "hi");
fragment.setArguments(bundle);
On your Tab1Fragment.java you can try something like this:
if(getArguments()!=null){
String sentString = getArguments().getString("operator");
}