I was looking answer in similar topics but nothing works for me. I have Activity which has a fragment. This fragment has adapter. Everything is fine even if I rotate screen, but when I rotate screen and try to update adapter (for example by sort items in adapter - method sort) I get NULL on adapter.
When Activity starts first time this is happening:
ON CREATE (ACTIVITY)
SETUP VIEW PAGER (ACTIVITY)
CONSTRUCTOR (FRAGMENT)
SET DATA IN ADAPTER (ACTIVITY)
ON CREATE (FRAGMENT)
CREATE ADAPTER (FRAGMENT)
ON CREATE VIEW (FRAGMENT)
UPDATE ADAPTER (FRAGMENT)
ON ACTIVITY CREATED (FRAGMENT)
In the second time when I rotate screen:
ON CREATE (ACTIVITY)
CONSTRUCTOR (FRAGMENT)
ON CREATE (FRAGMENT)
CREATE ADAPTER (FRAGMENT)
SETUP VIEW PAGER (ACTIVITY)
CONSTRUCTOR (FRAGMENT)
SET DATA IN ADAPTER (ACTIVITY)
ON CREATE VIEW (FRAGMENT)
UPDATE ADAPTER (FRAGMENT)
ON ACTIVITY CREATED (FRAGMENT)
So the problem is that in activity method super.onCreate(savedInstanceState) the fragment is recreated istelf. I was trying pass NULL for super.onCreate(null) and also checking if savedInstance is NULL, changing FragmentPagerAdapter for FragmentStatePagerAdapter, and many others things. What I want to do is save and get fragment, adapter in proper way or just make activity start everytime like in the first time.
PART OF MAIN ACTIVITY
public class MainActivity extends AppCompatActivity {
private TabLayout tabLayout;
private ViewPager viewPager;
SongsFragment songsFragment;
TabAdapter tabAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(null);
setContentView(R.layout.activity_main);
//init work
tabAdapter = new TabAdapter(getSupportFragmentManager());
songsFragment = new SongsFragment();
songsFragment.setData(database.getSongs(readOption(), readOrder()));
tabAdapter.addFragment(songsFragment, "TAB");
viewPager.setAdapter(tabAdapter);
tabLayout.setupWithViewPager(viewPager);
}
public void sort() {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setItems(R.array.sorts, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
if(which == 0) writeSort("number", "ASC");
else if(which == 1) writeSort("number", "DESC");
else if(which == 2) writeSort("title", "ASC");
else if(which == 3) writeSort("title", "DESC");
songsFragment.setData(database.getSongs(readOption(), readOrder()));
songsFragment.updateAdapter();
}
}).show();
}
}
FRAGMENT
public class SongsFragment extends Fragment {
private RecyclerView recyclerView;
List<Song> songs = new ArrayList<>();
SongsAdapter adapter;
public SongsFragment() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.v("TAG", "onCr");
if(!(savedInstanceState == null || !savedInstanceState.containsKey("list"))) {
songs = (List<Song>) savedInstanceState.getSerializable("list");
}
createAdapter();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
Log.v("TAG", "onCrV");
View view = inflater.inflate(R.layout.fragment_songs, container, false);
recyclerView = (RecyclerView) view.findViewById(R.id.fragment_songs_SongsList);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
recyclerView.setAdapter(adapter);
updateAdapter();
return view;
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putSerializable("list", (Serializable) songs);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
public void setData(List<Song> songs) {
this.songs = songs;
}
public void createAdapter() {
adapter = new SongsAdapter(getContext(), songs);
}
public void updateAdapter() {
adapter.clear();
adapter.addAll(songs);
adapter.notifyDataSetChanged();
}
}
FRAGMENT PAGER ADAPTER
public class TabAdapter extends FragmentStatePagerAdapter {
List<Fragment> fragments = new ArrayList<>();
List<String> titles = new ArrayList<>();
public TabAdapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return fragments.get(position);
}
#Override
public int getCount() {
return fragments.size();
}
#Override
public CharSequence getPageTitle(int position) {
return titles.get(position);
}
public void addFragment(Fragment fragment, String title) {
fragments.add(fragment);
titles.add(title);
}
}
Related
I'm trying to update my WebView in a Fragment when RecyclerView Item is clicked. In the debug console it's printing my hard-coded URL, but it's not updating the View - it is staying on "Google" webpage without any changes, but seems like onClickListener is working.
MainActivity.java
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private RecyclerView.Adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Add Websites
ArrayList<Website> websitesList = new ArrayList<>();
websitesList.add(new Website(R.drawable.ic_launcher_background, "Line 1", "https://google.com/"));
websitesList.add(new Website(R.drawable.ic_launcher_background, "Line 2", "https://yahoo.com/"));
websitesList.add(new Website(R.drawable.ic_launcher_background, "Line 3", "https://abv.bg/"));
mRecyclerView = findViewById(R.id.recyclerView);
mLayoutManager = new LinearLayoutManager(this);
mAdapter = new WebsiteAdapter(websitesList);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
}
public void switchContent(int id, Fragment fragment) {
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.add(id, fragment);
ft.commit();
}
}
RecyclerView Adapter
#Override
public void onBindViewHolder(#NonNull ExampleViewHolder holder, int position) {
final Website currentItem = mWebsiteList.get(position);
holder.mImageView.setImageResource(currentItem.getImage());
holder.mTitle.setText(currentItem.getTitle());
holder.mTitle.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
fragmentJump(currentItem);
}
});
}
#Override
public int getItemCount() {
return mWebsiteList.size();
}
private void fragmentJump(Website mItemSelected) {
Fragment mFragment = new WebsiteView();
Bundle mBundle = new Bundle();
mBundle.putString("url", "http://facebook.com/");
mFragment.setArguments(mBundle);
switchContent(R.id.fragment, mFragment);
}
public void switchContent(int id, Fragment fragment) {
if (mContext == null)
return;
if (mContext instanceof MainActivity) {
MainActivity mainActivity = (MainActivity) mContext;
mainActivity.switchContent(id, fragment);
}
}
WebView Fragment
private WebView webView;
String mUrl;
public WebsiteView() {}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_website_view, container, false);
try {
mUrl = getArguments().getString("url");
} catch(Exception ex) {
System.out.println(ex.toString());
mUrl = "http://google.com/";
}
System.out.println(mUrl);
webView = v.findViewById(R.id.webView);
webView.setWebViewClient(new WebViewClient());
webView.loadUrl(mUrl);
return v;
}
Okay, it appeared that I'm actually trying to update the Fragment data, and when I replace another fragment with my desired one it works. Any ideas how to update the WebView in the fragment?
I got a problem with updating ViewPager fragments. We need to show fragments with data to registered user, when he doesn't registered we need to show fragments with message to register. I use this method to check it in MainActivity:
#Override
public void setAdapter(boolean isUserExist) {
Log.d("RegDebug", "In setAdapter");
mainPagerAdapter.clearData();
mainPagerAdapter.addFragment(searchFragment, getString(R.string.search_title));
if (isUserExist) {
Log.d("RegDebug", "In setAdapter reg");
mainPagerAdapter.addFragment(new ChatsFragment(), getString(R.string.chats_title));
mainPagerAdapter.addFragment(new ActionsFragment(), getString(R.string.actions_title));
Toast.makeText(getApplicationContext(), "Registered!", Toast.LENGTH_SHORT).show();
} else {
Log.d("RegDebug", "In setAdapter unreg");
mainPagerAdapter.addFragment(RegisterFragment.newInstance(Consts.CHATS_TAB_NAME), getString(R.string.chats_title));
mainPagerAdapter.addFragment(RegisterFragment.newInstance(Consts.ACTIONS_TAB_NAME), getString(R.string.actions_title));
Toast.makeText(getApplicationContext(), "Unregistered!!!", Toast.LENGTH_SHORT).show();
}
mainPagerAdapter.notifyDataSetChanged();
viewPager.setAdapter(mainPagerAdapter);
}
I call this method in presenter with setting value from firebase auth, checking if user exists:
public void checkForUserExist() {
if (mainInteractor.isUserExist()) {
getViewState().setRegAdapter();
} else getViewState().setUnregAdapter();
}
And then call presenter method in onCreate of MainActivity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
dialogFragment = new FilterDialogFragment();
searchFragment = new SearchFragment();
//UI
toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
viewPager = findViewById(R.id.main_view_pager);
tabLayout = findViewById(R.id.main_tabs);
//mainPagerAdapter = new MainPagerAdapter(getSupportFragmentManager());
mainPresenter.checkForUserExist();
tabLayout.setupWithViewPager(viewPager);
}
I try to log the boolean result and it returns exactly value that must be, but pager adapter can't update its content.Code of MainPagerAdapter:
public class MainPagerAdapter extends FragmentPagerAdapter{
private final List<Fragment> fragmentList = new ArrayList<>();
private final List<String> fragmentTitleList = new ArrayList<>();
public MainPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int position) {
return fragmentList.get(position);
}
#Override
public int getCount() {
return fragmentTitleList.size();
}
#Nullable
#Override
public CharSequence getPageTitle(int position) {
return fragmentTitleList.get(position);
}
public void addFragment(Fragment fragment, String title){
fragmentList.add(fragment);
fragmentTitleList.add(title);
}
public void clearData(){
fragmentList.clear();
fragmentTitleList.clear();
notifyDataSetChanged();
Log.d("RegDebug", " fragmentList size is " + fragmentList.size()
+ " fragmentTitleList size is " + fragmentTitleList.size());
}
}
Use OnPageChangeListener of ViewPager class & notify to your current fragment from there using interface.
I have a Fragment that contains a RecyclerView. I am trying to implement a filter on the RecyclerView. The filter UI opens a new Fragment Dialog where the user will input a value. Once the user hits the Search Button in the Fragment Dialog, the value should be returned to the RecyclerView Fragment and the existing data in the view should be cleared. I want to re-populate the RecyclerView with the new set of data that I will obtain from the server. My problem is that, I have a method called resetAdapterDetails() in the RecyclerView Fragment which works as expected if called from the RecyclerView Fragment itself. But, when I try to call the same method from the Fragment Dialog, I get an exception:
transactionList.clear(); --> is trying to clear a list which is null
Though the data is still visible in the RecyclerView.
The RecyclerView Fragment:
public class TransactionHistoryFragment extends Fragment implements SearchView.OnQueryTextListener, DateRangePickerFragment.OnDateRangeSelectedListener{
private RecyclerView recyclerview;
private TransactionHistoryAdapter adapter;
private List<Transaction> transactionList;
public TransactionHistoryFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_transaction_history, container, false);
recyclerview = (RecyclerView) view.findViewById(R.id.recyclerview);
LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
recyclerview.setLayoutManager(layoutManager);
return view;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
setHasOptionsMenu(true);
getTransactionHistory("");
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.transactions_history_menu, menu);
final MenuItem searchItem = menu.findItem(R.id.action_search);
final SearchView searchView = (SearchView) MenuItemCompat.getActionView(searchItem);
searchView.setOnQueryTextListener(this);
super.onCreateOptionsMenu(menu, inflater);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.filter_date:
FragmentManager fmDate = getActivity().getFragmentManager();
DateRangePickerFragment dialogFragmentDate = DateRangePickerFragment.newInstance(this, true);
dialogFragmentDate.show(fmDate, "Sample Fragment");
return true;
case R.id.filter_mobile:
FragmentManager fmMobile = getActivity().getFragmentManager();
SearchMobileFragment dialogFragmentMobile = new SearchMobileFragment ();
dialogFragmentMobile.show(fmMobile, "Sample Fragment");
//resetAdapterDetails();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
#Override
public boolean onQueryTextChange(String newText) {
final List<Transaction> filteredModelList = filter(transactionList, newText);
adapter.setFilter(filteredModelList);
return true;
}
#Override
public boolean onQueryTextSubmit(String query) {
return false;
}
//for filtering the list
private List<Transaction> filter(List<Transaction> models, String query) {
query = query.toLowerCase();final List<Transaction> filteredModelList = new ArrayList<>();
for (Transaction model : models) {
final String text = model.getTxnStatus().toLowerCase();
if (text.contains(query)) {
filteredModelList.add(model);
}
}
return filteredModelList;
}
//for populating the list
private void getTransactionHistory(String agentId){
GetTransactionHistoryTask task = new GetTransactionHistoryTask("agent1", "password");
task.getTransactionsByAgent("OU23","OU230000000123456789").subscribe(transactionHistoryResponse -> {
if(transactionHistoryResponse != null && transactionHistoryResponse.getTransactions() != null && transactionHistoryResponse.getTransactions().size() > 0 && transactionHistoryResponse.getErrors().size() == 0){
transactionList = transactionHistoryResponse.getTransactions();
adapter = new TransactionHistoryAdapter(transactionList);
recyclerview.addItemDecoration(new DividerItemDecoration(getActivity(), LinearLayoutManager.VERTICAL));
recyclerview.setAdapter(adapter);
onClickListnerRecyclerView();
}
else{
}
}, e -> e.printStackTrace());
}
private void onClickListnerRecyclerView() {
recyclerview.addOnItemTouchListener(
new RecyclerItemClickListener(getActivity(), new RecyclerItemClickListener.OnItemClickListener() {
#Override
public void onItemClick(View view, int position) {
try {
final Transaction transactionModel= (Transaction) adapter.getObjectAt(position);
Intent i = new Intent(getActivity(), TransactionDetailsActivity.class);
i.putExtra("transaction_object",transactionModel);
startActivity(i);
}
catch (Exception e){
Log.e("List issue", e.toString());
}
}
})
);
}
#Override
public void onDateRangeSelected(int startDay, int startMonth, int startYear, int endDay, int endMonth, int endYear) {
}
public void fetchDateRange(String startDate, String endDate) {
Log.e("DateRange",startDate + "\n" + endDate);
}
public void fetchMobileNumber(String mobileNumber) {
Log.e("Mobile",mobileNumber);
resetAdapterDetails();
}
public boolean resetAdapterDetails(){
try {
transactionList.clear();
adapter.notifyDataSetChanged();
recyclerview.setAdapter(adapter);
} catch (Exception e) {
Log.e("Reset Error", ""+e.getMessage());
}
return true;
}
}
The Dialog Fragment:
public class SearchMobileFragment extends DialogFragment {
EditText mMobileNumberEditText;
Button search_button;
public SearchMobileFragment() {
// Required empty public constructor
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_search_mobile, container, false);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
mMobileNumberEditText = (EditText) view.findViewById(R.id.mobile_number_editText);
search_button = (Button) view.findViewById(R.id.search_button);
search_button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
dismiss();
TransactionHistoryFragment obj = new TransactionHistoryFragment();
obj.fetchMobileNumber(mMobileNumberEditText.getText().toString());
}
});
}
}
The fetchMobileNumber() method in the TransactionHistoryFragment (RecyclerView Fragment) is called through the fetchMobileNumber() method which is called from the SearchMobileFragment (Dialog Fragment).
Where am I going wrong? Why the transactionList.clear(); is throwing the null pointer exception?
You are getting the issue because you are creating new TransactionHistoryFragment instance search_button click in SearchMobileFragment. Which makes it's all variables null and initialize it again and here your transactionList becomes null.
You can achieve the same thing easily with different way also. As the place of SearchMobileFragment as a DialogFragment you can make it as Activity and start it as startActivityForResult from your TransactionHistoryFragment and implement onActivityResult callback to doing the fiteration.
But right now in your case you can manage it in different ways also:
First way:
As you are doing in your DialogFragment
search_button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
dismiss();
/*TransactionHistoryFragment obj = new TransactionHistoryFragment();
obj.fetchMobileNumber(mMobileNumberEditText.getText().toString());*/
}
});
Don't do the call for fetchMobileNumber here, in onResume of your TransactionHistoryFragment you should make a call for this. On the click of search_button save the filter data to SharedPreferences and use that in onResume of the TransactionHistoryFragment for filtering and after that clear this saved data from SharedPreferences onPause of this fragment.
You should remove
transactionList.clear();
of code from resetAdapterDetails() in TransactionHistoryFragment, because after search filter you will get updated transactionList which is already passed to adapter then forcefully no need to clear it. Or have a check before clearing it like:
if(transactionList!=null){
transactionList.clear();
}
Second way: Using BroadcastReceiver you can achieve the same thing.
Register a receiver in your TransactionHistoryFragment and sendBroadcast from SearchMobileFragment. In onReceive of the TransactionHistoryFragment do the filtration process.
I had resolved the above issue in a different way. In the Dialog Fragment I have implemented a View.OnClickListener and have created an Interface to initialize the same from the RecyclerView Fragment. I am posting the complete source codes below; the SearchMobileFragment now looks like:
public class SearchMobileFragment extends DialogFragment implements View.OnClickListener{
private OnMobileNumberSelectedListener onMobileNumberSelectedListener;
EditText mMobileNumberEditText;
Button mSearchButton;
public SearchMobileFragment() {
// Required empty public constructor
}
public static SearchMobileFragment newInstance(OnMobileNumberSelectedListener callback) {
SearchMobileFragment searchMobileFragment = new SearchMobileFragment();
searchMobileFragment.initialize(callback);
return searchMobileFragment;
}
public void initialize(OnMobileNumberSelectedListener callback) {
onMobileNumberSelectedListener = callback;
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_search_mobile, container, false);
getDialog().getWindow().requestFeature(Window.FEATURE_NO_TITLE);
mMobileNumberEditText = (EditText) root.findViewById(R.id.mobile_number_editText);
mSearchButton = (Button) root.findViewById(R.id.search_button);
mSearchButton.setOnClickListener(this);
return root;
}
#Override
public void onStart() {
super.onStart();
if (getDialog() == null)
return;
getDialog().getWindow().setLayout(WindowManager.LayoutParams.MATCH_PARENT, WindowManager.LayoutParams.WRAP_CONTENT);
}
public void setOnMobileNumberSelectedListener(OnMobileNumberSelectedListener callback) {
this.onMobileNumberSelectedListener = callback;
}
#Override
public void onClick(View v) {
dismiss();
onMobileNumberSelectedListener.onMobileNumberSelected(mMobileNumberEditText.getText().toString());
}
public interface OnMobileNumberSelectedListener {
void onMobileNumberSelected(String mobileNumber);
}
}
The RecyclerView Fragment modifications:
public class TransactionHistoryFragment extends Fragment implements SearchView.OnQueryTextListener,
DateRangePickerFragment.OnDateRangeSelectedListener, SearchMobileFragment.OnMobileNumberSelectedListener{
private RecyclerView recyclerview;
private TransactionHistoryAdapter adapter;
private List<Transaction> transactionList;
SearchView search;
public static final String TIMERANGEPICKER_TAG = "timerangepicker";
public TransactionHistoryFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_transaction_history, container, false);
recyclerview = (RecyclerView) view.findViewById(R.id.recyclerview);
LinearLayoutManager layoutManager = new LinearLayoutManager(getActivity());
recyclerview.setLayoutManager(layoutManager);
return view;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
setHasOptionsMenu(true);
getTransactionHistory();
}
#Override
public void onResume() {
Log.e("onResumeTHF","invoked");
super.onResume();
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.transactions_history_menu, menu);
search = (SearchView) menu.findItem(R.id.action_search).getActionView();
search.setOnQueryTextListener(this);
super.onCreateOptionsMenu(menu, inflater);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.filter_date:
FragmentManager fmDate = getActivity().getFragmentManager();
DateRangePickerFragment dialogFragmentDate = DateRangePickerFragment.newInstance(this, true);
dialogFragmentDate.show(fmDate, "Sample Fragment");
return true;
case R.id.filter_mobile:
FragmentManager fmMobile = getActivity().getFragmentManager();
SearchMobileFragment dialogFragmentMobile = SearchMobileFragment.newInstance(this);
dialogFragmentMobile.show(fmMobile, "Sample Fragment");
return true;
default:
return super.onOptionsItemSelected(item);
}
}
#Override
public boolean onQueryTextChange(String newText) {
Log.e("newText",newText);
final List<Transaction> filteredModelList = filter(transactionList, newText);
adapter.setFilter(filteredModelList);
return true;
}
#Override
public boolean onQueryTextSubmit(String query) {
return false;
}
#Override
public void onMobileNumberSelected(String mobileNumber) {
Log.e("mobileNumber",mobileNumber);
resetAdapterDetails();
}
public boolean resetAdapterDetails(){
try {
transactionList.clear();
adapter.notifyDataSetChanged();
recyclerview.setAdapter(adapter);
} catch (Exception e) {
Log.e("Reset Error", ""+e.getMessage());
}
return true;
}
}
Happy coding!
The null pointer exception is because when you create a new TransactionHistoryFragment using new onViewCreated is not called and hence transactionList is never initialized. You can create a setter for the list or pass it as a constructor to the fragment to fix this
in my app i have a Tabs with fragment classes. i trying to refresh listView in "fragment a" with the new data i insert.
In "fragment b" i have EditText and Button ,that inserting text to the database.
in "fragment a" i have the ListView with the dataBase rows. when "fragment a" is "OnCreateView" i just put the dataBase on a "ArrayList" and past it to my baseAdapter.
but "onCreateView" not refreshing my new data every time i get into the "fragment a" else i goes to "fragment c" and "onDestroy" call on "fragment a".
so my result it was to call : "setUserVisibleHint" override method, and check if it is visible and refreshing the list.
but i dont think it is the good practice .
what should i do?
Class a
public class ListFragment extends Fragment{
basAdapterCustom adapter;
ListView lv;
ArrayList<Clock> list;
private DbHandler hand;
Context context;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.list_fragment, container, false);
context = getActivity();
Log.d(TAG, "onCreateView");
hand = new DbHandler(context);
list = new ArrayList<Clock>();
lv = (ListView) v.findViewById(R.id.listOfShifts);
adapter = new basAdapterCustom(list, getActivity());
lv.setAdapter(adapter);
refreshList();
return v;
}
//like on "resume":
#Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
// Make sure that we are currently visible
if (this.isVisible()) {
refreshList();
if (!isVisibleToUser) {
// TODO stop
}
}
}
private void refreshList() {
list = hand.getByWorkName();
adapter = new basAdapterCustom(list,getActivity());
lv.setAdapter(adapter);
}
class b:
public class ClockFragment extends Fragment{
DbHandler hand;
Context context;
#Override
public View onCreateView(LayoutInflater inflater,
#Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.clock, container,false);
context = getActivity();
hand = new DbHandler(context);
return v;
}
// ADD to .Db
public void addToDb(View v){
hand.add(new Clock(0, dateDay));
}
}
class mainActivity:
public class MainActivity extends FragmentActivity implements ActionBar.TabListener, OnPageChangeListener{
public static final String TAG = "myClock";
String[] tabMenu = {"FRAG A","FRAG B","FRAG C"};
private ViewPager viewPager;
private TabPagerAdapter mAdapter;
private ActionBar actionBar;
#SuppressLint("NewApi")
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.d(MainActivity.TAG, "OnCreate = MainActivity (Pager");
viewPager = (ViewPager) findViewById(R.id.pager );
actionBar = getActionBar();
mAdapter = new TabPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(mAdapter);
actionBar.setHomeButtonEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
for (String tabsNames : tabMenu) {
actionBar.addTab(actionBar.newTab().setText(tabsNames).setTabListener(this));
}
viewPager.setOnPageChangeListener(this);
}
// public void transDialog(){
// Dialog mDialog = new Dialog(this, android.R.style.Theme_Translucent_NoTitleBar_Fullscreen);
// }
#Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
viewPager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
// TODO Auto-generated method stub
}
#Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
#Override
public void onPageScrollStateChanged(int arg0) {
}
#Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
#Override
public void onPageSelected(int position) {
actionBar.setSelectedNavigationItem(position);
}
}
PagetAdapter.class
public class TabPagerAdapter extends FragmentPagerAdapter {
private static final String TAG = "myClock";
public TabPagerAdapter(FragmentManager fm) {
super(fm);
// TODO Auto-generated constructor stub
}
#Override
public Fragment getItem(int index) {
Log.d(TAG, " CLASS : TabPagerAdapter");
switch (index) {
case 0:
return new ListFragment();
case 1:
return new ClockFragment();
case 2:
return new SettingFragment();
default:
break;
}
Log.d(TAG, " CLASS : TabPagerAdapter = "+index);
return null;
}
#Override
public int getCount() {
return 3;
}
}
Please help me i hope you are understand my problem...
You want to update listView in fragment A, after insert data in fragment b? Then you have a few solutions to choose:
1. Implement communications between fragments via activity. Then B insert date, it send message to activity, that data need to be updated. Then fragment A started, it's ask activity to need update data. For details on implementing this communication check link.
2. Use some bus library, EventBus for example. Then fragment B insert data, it post 'data changed' event to bus. Fragment A checks on start if this event occurs.
3. Use Loaders which "monitor the source of their data and deliver new results when the content changes."
I'm currently using FragmentStatePagerAdapter and I would like it to have a "navigate up" feature (DisplayHomeAsUpEnabled). When I set the following code it shows up as a correct navigate back button. But nothing happens when I click on it, can you guys see anything that I', doing wrong in my code, I get no error while pressing the "navigate up" button and I get no compiler errors.
Here is the code, its in the "public boolean onOptionsItemSelected(MenuItem item) {" it gets interesting at the bottom.
public class ShareholdingDetailFragment extends FragmentActivity {
final int NUM_ITEMS = Portfolio.getPortfolio().count();
MyAdapter mAdapter;
ViewPager mPager;
Bundle extras;
#Override
protected void onCreate(Bundle savedInstanceState) {
System.out.println(NUM_ITEMS + "e");
super.onCreate(savedInstanceState);
setContentView(R.layout.shareholdingdetailview_fragment_wrapper);
mAdapter = new MyAdapter(getSupportFragmentManager());
mPager = (ViewPager)findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
}
public class MyAdapter extends FragmentStatePagerAdapter {
public MyAdapter(FragmentManager fm) {
super(fm);
}
public int getCount() {
return NUM_ITEMS;
}
public Fragment getItem(int position) {
return ShareholdingFragment.newInstance(position);
}
}
public static class ShareholdingFragment extends Fragment {
int mNum;
static ShareholdingFragment newInstance(int num) {
ShareholdingFragment f = new ShareholdingFragment();
// Supply num input as an argument.
Bundle args = new Bundle();
args.putInt("num", num);
f.setArguments(args);
return f;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mNum = getArguments() != null ? getArguments().getInt("num") : 1;
}
#SuppressLint({ "NewApi", "NewApi" })
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.shareholdingdetailview_fragment, container, false);
/****************Setting the Display as home and it shows*******************/
ActionBar bar = getActivity().getActionBar();
bar.setDisplayHomeAsUpEnabled(true);
/**********************************/
return view;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home://Not working
System.out.println("test");//This isn't printed out
Intent upIntent = new Intent(getActivity(), DetailShareHoldingActivity.class);
if (NavUtils.shouldUpRecreateTask(getActivity(), upIntent)) {
getActivity().finish();
} else {
NavUtils.navigateUpTo(getActivity(), upIntent);
}
return true;
}
return super.onOptionsItemSelected(item);
}
}
}
Try adding: setHasOptionsMenu(true); in your onCreate() in ShareholdingFragment.
Add setHomeButtonEnabled(true) on API Level 14 and higher when you configure your action bar. On API Level 11-13, the home button is enabled automatically.
If you're using the new Toolbar and ActionbarDrawerToggle. You can assign clickHandler directly. For my activities that have this drawer toolbar I implemented an interface to enable drawer if at root,
#Override
public void enableDrawer(boolean enable) {
mDrawerToggle.setDrawerIndicatorEnabled(enable);
mDrawerToggle.setToolbarNavigationClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Pop fragment back stack or pass in a custom click handler from the fragment.
}
});
}