I am creating an activity that contains three fragments for tabs.I want to set the data from an object(which is available in parent activity) to the child views of the fragment.I tried doing this through public methods of fragment.But when trying to access the views,It returns null pointer exception and the app crashes.Can anyone help me to solve this problem?
Parent activity is :
public class EnquiryViewActivity extends AppCompatActivity implements IFragmentToActivity {
private Context mContext;
// Session Manager Class
SessionManagement session;
private RequestQueue requestQueue;
private Gson gson;
//String enquiryId;
int enId, uid;
Enquiry enquiry;
// Alert Dialog Manager
AlertDialogManager alert = new AlertDialogManager();
/* Button btn_MoreEnqDetails, btn_ToSiteVisit, btn_nextEnq2;
EditText etName, etAddress, etSiteAddress, etPhoneNo, etMob, etEmail;
private RadioGroup rgrp_familyType;
private RadioButton radioSelectedFamilyType;
*/
private TabLayout addenqtabLayout;
private ViewPager addenqviewPager;
//Fragments
ContactFragment contactFragment;
RequirementsFragment requirementsFragment;
FollowUpFragment followupFragment;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_enquiry);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
//--------------------------------------------
//Initializing viewPager
addenqviewPager = (ViewPager) findViewById(R.id.addenqviewpager);
addenqviewPager.setOffscreenPageLimit(3);
//Initializing the tablayout
addenqtabLayout = (TabLayout) findViewById(R.id.addenqtablayout);
addenqtabLayout.setupWithViewPager(addenqviewPager);
addenqviewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
addenqviewPager.setCurrentItem(position, false);
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
setupViewPager(addenqviewPager);
//----------------------------------------------
enquiry = new Enquiry();
try {
mContext = this;
enId = getIntent().getIntExtra("EnquiryId", -1);
uid = getIntent().getIntExtra("UserId", -1);
if (enId != -1) {
Log.d("h", "get enqid is " + enId);
enquiry = EnquiryORM.findEnquiryById(mContext, enId);
} else {
Log.d("h", "didn't get bid");
}
/*int position = tabLayout.getSelectedTabPosition();
Fragment fragment = adapter.getFragment(tabLayout
.getSelectedTabPosition());
if (fragment != null) {
switch (position) {
case 0:
((TabFragment1) fragment).onRefresh();
break;
case 1:
((TabFragment2) fragment).onRefresh();
break;
}
}*/
contactFragment.setDataToScreen(enquiry);
contactFragment.disableAllViews();
} catch (NumberFormatException e) {
Log.d("NumberFormatException: ", "some int is null");
Log.d("NumberFormatException: ", e.getMessage());
}
}
//---------------------------------------------------------------
@Override
public void showToast(String msg) {
Toast.makeText(this, msg, Toast.LENGTH_LONG).show();
}
@Override
public void communicateToFragment2() {
/*RequirementsFragment fragment = (RequirementsFragment) adapter.getFragment(1);
if (fragment != null) {
fragment.fragmentCommunication();
} else {
Log.i("log", "Fragment 2 is not initialized");
}*/
}
@Override
public void gotoMoreDetails() {
if (ConnectivityReceiver.isConnected()) {
//fetch and
//send indent to next activity to view more details
//show option to edit details
fetchMoreEnquiryDetails();
} else {
alert.showAlertDialog(EnquiryViewActivity.this, "Network Error", "Internet is not available!\nCannot connect to server", false);
}
}
@Override
public void gotoSiteVisit() {
Intent in = new Intent(EnquiryViewActivity.this, SiteVisitViewActivity.class);
in.putExtra("EnquiryId", enId);
in.putExtra("UserId", uid);
startActivity(in);
}
@Override
public void saveDataContacts(Enquiry enq) {
if (enquiry != null) {
enq.setId(enquiry.getId());
enq.setStatus(enquiry.getStatus());
enq.setUser_id(enquiry.getUser_id());
enq.setEnqstatusnew(enquiry.getEnqstatusnew());
enq.setCreateddate(getDateTime());
}
int enI=(int)EnquiryORM.insertEnquiry(mContext, enq);
enq.setId(enI);
}
//-----------------------------------------------------------------------
private void setupViewPager(ViewPager viewPager) {
ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
contactFragment = new ContactFragment();
requirementsFragment = new RequirementsFragment();
followupFragment = new FollowUpFragment();
adapter.addFragment(contactFragment, "CONTACT DETAILS");
adapter.addFragment(requirementsFragment, "REQUIREMENTS");
adapter.addFragment(followupFragment, "FOLLOW-UP");
viewPager.setAdapter(adapter);
}
private void fetchMoreEnquiryDetails() {
// Get a RequestQueue
// RequestQueue requestQueue = MyVolleySingleton.getInstance(this.getApplicationContext()).getRequestQueue();
requestQueue = Volley.newRequestQueue(this);
//create gson instance which is used to parse json
GsonBuilder gsonBuilder = new GsonBuilder();
gsonBuilder.excludeFieldsWithoutExposeAnnotation();
//gsonBuilder.setDateFormat("M/d/yy hh:mm a");
gson = gsonBuilder.create();
StringRequest sr = new StringRequest(Request.Method.POST, EndPoints.GET_SELECTED_ENQUIRIES_URL, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d("d", "getting response.........\n" + response);
Toast.makeText(getApplicationContext(), "Selected Enquiry JSON data :" + response, Toast.LENGTH_LONG).show();
//Enquiry detailEnquiry = gson.fromJson(response, Enquiry.class);
//detailEnquiry.setUser_id(uid);
Enquiry detailEnquiry = new Enquiry();
List<Enquiry> enquiryList = Arrays.asList(gson.fromJson(response, Enquiry[].class));
for (Enquiry enqu : enquiryList) {
detailEnquiry = enqu;
}
forwardToViewEnquiryMoreDetails(detailEnquiry);
/*Log.d("e", "All data inserted...now display.........");
List<Enquiry> enqlist= EnquiryORM.getEnquiries(getBaseContext());
for(Enquiry i:enqlist) {
Log.d("e", "enquiry :" +i.getId());
Log.d("e", i.getName()+","+i.getStatus()+","+i.getAddress()+","+i.getUser_id());
}
*/
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e("EnqViewActivity", error.toString());
Toast.makeText(getApplicationContext(), "Error: " + error.getMessage(), Toast.LENGTH_LONG).show();
}
}) {
@Override
protected Map<String, String> getParams() throws AuthFailureError {
Log.d("d", "inside getparams()...\n");
Map<String, String> params = new HashMap<String, String>();
params.put("enquiryid", String.valueOf(enId));
params.put("userid", String.valueOf(uid));
Log.d("d", "enquiry id to pass:" + enId + "\n");
return params;
}
};
// Add the request to RequestQueue.
// MyVolleySingleton.getInstance(this).addToRequestQueue(sr);
requestQueue.add(sr);
Log.d("d", "Added to queue");
}
//-----------------------------------------------------------------------
private void forwardToViewEnquiryMoreDetails(Enquiry detailedEnquiry) {
Gson mynewgson = new Gson();
String DEnquiryDataObjectAsString = mynewgson.toJson(detailedEnquiry);
Intent toDetail = new Intent(EnquiryViewActivity.this, EnquiryViewMoreActivity.class);
toDetail.putExtra("DetailedEnquiryDataObjectAsString", DEnquiryDataObjectAsString);
startActivity(toDetail);
// close this activity
//finish();
}
private String getDateTime() {
SimpleDateFormat dateFormat = new SimpleDateFormat(
"yyyy-MM-dd HH:mm:ss", Locale.getDefault());
Date date = new Date();
return dateFormat.format(date);
}
//---------------------------------------------------------------
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.view_enq, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_add_enquiry) {
startActivity(new Intent(EnquiryViewActivity.this, EnquiryAddActivity.class));
return true;
}
if (id == R.id.action_edit_enquiry) {
// Make all fields editable
contactFragment.enableAllViews();
return true;
}
return super.onOptionsItemSelected(item);
}
}
Fragment code is :
public class ContactFragment extends Fragment implements View.OnClickListener {
private IFragmentToActivity mCallback;
Button btn_MoreEnqDetails, btn_ToSiteVisit, btn_nextEnq1;
EditText etName, etAddress, etSiteAddress, etPhoneNo, etMob, etEmail;
public ContactFragment() {
// Required empty public constructor
}
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_contact, container, false);
btn_MoreEnqDetails = (Button) view.findViewById(R.id.btn_MoreEnqDetails);
btn_ToSiteVisit = (Button) view.findViewById(R.id.btn_ToSiteVisit);
btn_nextEnq1 = (Button) view.findViewById(R.id.btn_nextEnq1);
etName = (EditText) view.findViewById(R.id.etClientName);
etAddress = (EditText) view.findViewById(R.id.etAddress);
etSiteAddress = (EditText) view.findViewById(R.id.etSiteAddress);
etPhoneNo = (EditText) view.findViewById(R.id.etPhoneNo);
etMob = (EditText) view.findViewById(R.id.etMob);
etEmail = (EditText) view.findViewById(R.id.etEmail);
btn_MoreEnqDetails.setOnClickListener(this);
btn_ToSiteVisit.setOnClickListener(this);
btn_nextEnq1.setOnClickListener(this);
return view;
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_MoreEnqDetails:
mCallback.showToast("Hello from Fragment 1");
break;
case R.id.btn_ToSiteVisit:
mCallback.gotoSiteVisit();
break;
case R.id.btn_nextEnq1:
Enquiry enq=new Enquiry();
enq=getDataFromViews(enq);
mCallback.saveDataContacts(enq);
break;
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
try {
mCallback = (IFragmentToActivity) context;
} catch (ClassCastException e) {
throw new ClassCastException(context.toString()
+ " must implement IFragmentToActivity");
}
}
@Override
public void onDetach() {
mCallback = null;
super.onDetach();
}
public void onRefresh() {
Toast.makeText(getActivity(), "Fragment 1: Refresh called.",
Toast.LENGTH_SHORT).show();
}
public void disableAllViews() {
Log.d("EnqViewAct: ", "disabling all views..");
btn_MoreEnqDetails.setEnabled(false);
btn_ToSiteVisit.setEnabled(false);
btn_nextEnq1.setEnabled(false);
etName.setEnabled(false);
etAddress.setEnabled(false);
etSiteAddress.setEnabled(false);
etPhoneNo.setEnabled(false);
etMob.setEnabled(false);
etEmail.setEnabled(false);
}
public void enableAllViews() {
Log.d("EnqViewAct: ", "enabling all views..");
btn_MoreEnqDetails.setEnabled(true);
btn_ToSiteVisit.setEnabled(true);
btn_nextEnq1.setEnabled(true);
etName.setEnabled(true);
etAddress.setEnabled(true);
etSiteAddress.setEnabled(true);
etPhoneNo.setEnabled(true);
etMob.setEnabled(true);
etEmail.setEnabled(true);
}
public void setDataToScreen(Enquiry enquiry) {
Log.d("EbqViewAct","Data to display : "
+enquiry.getId()+","+enquiry.getUser_id()+","+
enquiry.getStatus()+","+enquiry.getEnqstatusnew()+","+
enquiry.getCreateddate()+","+
enquiry.getName()+","+enquiry.getAddress()+","+
enquiry.getSiteaddress()+","+enquiry.getPhone_number()+","+
enquiry.getMobile_number()+","+enquiry.getEmail());
if(enquiry.getName()!=null && enquiry.getName()!="")
{etName.setText(enquiry.getName());}
if(enquiry.getAddress()!=null && enquiry.getAddress()!="")
{etAddress.setText(enquiry.getAddress());}
if(enquiry.getSiteaddress()!=null && enquiry.getSiteaddress()!="")
{etSiteAddress.setText(enquiry.getSiteaddress());}
if(enquiry.getPhone_number()!=null && enquiry.getPhone_number()!="")
{etPhoneNo.setText(enquiry.getPhone_number());}
if(enquiry.getMobile_number()!=null && enquiry.getMobile_number()!="")
{etMob.setText(enquiry.getMobile_number());}
if(enquiry.getEmail()!=null && enquiry.getEmail()!="")
{etEmail.setText(enquiry.getEmail());}
/* if (thisSv.getFamilytype() != null) {
if (thisSv.getFamilytype().equalsIgnoreCase("Nuclear")) {
rgrp_familyType.check(R.id.rbtn_nuclear);
} else if (thisSv.getFamilytype().equalsIgnoreCase("Join")) {
rgrp_familyType.check(R.id.rbtn_join);
} else {
rgrp_familyType.check(R.id.rbtn_nuclear);
}
}*/
}
public Enquiry getDataFromViews(Enquiry enq) {
/*
radioSelectedFamilyType = (RadioButton) findViewById(rgrp_familyType.getCheckedRadioButtonId());
if (radioSelectedFamilyType != null) {
newSv.setFamilytype(radioSelectedFamilyType.getText().toString());
}*/
if ((etName.getText().toString()) != "" && (etName.getText().toString()) != null) {
enq.setName(etName.getText().toString().trim());
}
if ((etAddress.getText().toString()) != "" && (etAddress.getText().toString()) != null) {
enq.setAddress(etAddress.getText().toString().trim());
}
if ((etSiteAddress.getText().toString()) != "" && (etSiteAddress.getText().toString()) != null) {
enq.setSiteaddress(etSiteAddress.getText().toString().trim());
}
if ((etPhoneNo.getText().toString()) != "" && (etPhoneNo.getText().toString()) != null) {
enq.setPhone_number(etPhoneNo.getText().toString().trim());
}
if ((etMob.getText().toString()) != "" && (etMob.getText().toString()) != null) {
enq.setMobile_number(etMob.getText().toString().trim());
}
if ((etEmail.getText().toString()) != "" && (etEmail.getText().toString()) != null) {
enq.setEmail(etEmail.getText().toString().trim());
}
return enq;
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
}
}
Interface is :
public interface IFragmentToActivity {
void showToast(String msg);
void communicateToFragment2();
void gotoMoreDetails();
void gotoSiteVisit();
void saveDataContacts(Enquiry enq);
}
PagerAdapter is :
public class ViewPagerAdapter extends FragmentStatePagerAdapter {
private final SparseArray<WeakReference<Fragment>> instantiatedFragments = new SparseArray<>();
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
@Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
@Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
@Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
@Override
public int getItemPosition(Object object){
return super.getItemPosition(object);
}
//--------------------------------------------------------
@Override
public Object instantiateItem(final ViewGroup container, final int position) {
final Fragment fragment = (Fragment) super.instantiateItem(container, position);
instantiatedFragments.put(position, new WeakReference<>(fragment));
return fragment;
}
@Override
public void destroyItem(final ViewGroup container, final int position, final Object object) {
instantiatedFragments.remove(position);
super.destroyItem(container, position, object);
}
@Nullable
public Fragment getFragment(final int position) {
final WeakReference<Fragment> wr = instantiatedFragments.get(position);
if (wr != null) {
return wr.get();
} else {
return null;
}
}
}
Error log is :
12-25 11:09:46.931 3136-3136/com.example.anjana.decorightkitchen E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.anjana.decorightkitchen, PID: 3136
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.anjana.decorightkitchen/com.example.anjana.decorightkitchen.activity.EnquiryViewActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.EditText.setText(java.lang.CharSequence)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.EditText.setText(java.lang.CharSequence)' on a null object reference
at com.example.anjana.decorightkitchen.fragment.ContactFragment.setDataToScreen(ContactFragment.java:149)
at com.example.anjana.decorightkitchen.activity.EnquiryViewActivity.onCreate(EnquiryViewActivity.java:140)
at android.app.Activity.performCreate(Activity.java:6237)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
NOTE : Enquiry object values are getting in the fragment properly. enqName.setText("hai") is working properly inside onCreateView() of fragment. But when enqName.setText("hai") put inside a public method of fragment,and called that method from onCreateView(), again nullpointer exception occurs.
