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Android: onSensorChanged() not called despite attaching listener

Couldn't find a solution from the existing posts. I'm trying to build a step counter using Android's built in TYPE_STEP_COUNTER sensor but the onSensorChange() method doesn't get called! In the below code, for example, "Outside stepcount" is never printed to the Logcat.
public class StepFragment extends Fragment implements SensorEventListener {
private int step_count = 0;
TextView stepCountText;
private Sensor mStepSensor;
private SensorManager mSensorManager;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.stepfragment, container, false);
stepCountText = (TextView)view.findViewById(R.id.stepcounttext);
return view;
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
mSensorManager = (SensorManager) getActivity().getSystemService(SENSOR_SERVICE);
mStepSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_STEP_COUNTER);
}
#Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
#Override
public void onSensorChanged(SensorEvent event) {
System.out.println("Outside" + step_count);
if (event.values[0] == 1.0f) {
step_count++;
System.out.println(step_count);
}
stepCountText.setText(Integer.toString(step_count));
}
#Override
public void onResume() {
super.onResume();
mSensorManager.registerListener(this, mStepSensor, SensorManager.SENSOR_DELAY_NORMAL);
if(mStepSensor != null)
{
System.out.println("Sensor step counter present");
}
}
#Override
public void onPause() {
super.onPause();
mSensorManager.unregisterListener(this);
System.out.println("Fragment Paused");
}
}
I do get "Sensor step counter present" in my Logcat which proves that my device indeed has the step_counter sensor. I'd be very grateful for some help!

What is the function that can be used instead of "this" in "Fragment"?

I'm implementing the autocomplete suggestion code in Google map place api.
We are using OnMapReadyCallback as an implement.
The MapView.getMapAsync(this) function was originally used in onCreateView. But now I'm going to use it in setupAutoCompleteFragment. However, in MapView.getMapAsync(this), it is not compiled due to this. What can be used?
public class googlemaptab extends Fragment implements OnMapReadyCallback {
MapView mapview;
Button kakaobutton;
public static googlemaptab newInstance(){
return new googlemaptab();
}
public googlemaptab() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_googlemaptab, container, false);
kakaobutton = (Button)view.findViewById(R.id.kakaobutton);
mapview = (MapView)view.findViewById(R.id.google_map_view);
setupAutoCompleteFragment();
return view;
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
kakaobutton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//클릭하면 카카오maptab으로 이동하겠다.
((MainActivity)getActivity()).replaceFragment(kakaomaptab.newInstance());
}
});
}
#Override
public void onStart() {
super.onStart();
mapview.onStart();
}
#Override
public void onResume() {
super.onResume();
mapview.onResume();
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
if(mapview != null)
{
mapview.onCreate(savedInstanceState);
}
}
#Override
public void onMapReady(GoogleMap googleMap) {
LatLng SEOUL = new LatLng(37.56, 126.97);
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(SEOUL);
markerOptions.title("서울");
markerOptions.snippet("수도");
googleMap.addMarker(markerOptions);
googleMap.moveCamera(CameraUpdateFactory.newLatLng(SEOUL));
googleMap.animateCamera(CameraUpdateFactory.zoomTo(13));
}
private void setupAutoCompleteFragment() {
PlaceAutocompleteFragment autocompleteFragment = (PlaceAutocompleteFragment)getActivity().
getFragmentManager().findFragmentById(R.id.place_autocomplete_fragment);
autocompleteFragment.setOnPlaceSelectedListener(new PlaceSelectionListener() {
#Override
public void onPlaceSelected(Place place) {
mapview.getMapAsync(this);
}
#Override
public void onError(Status status) {
Log.e("Error", status.getStatusMessage());
}
});
}
}

You could do it better this way
private void setupAutoCompleteFragment(OnMapReadyCallback instance) {
PlaceAutocompleteFragment autocompleteFragment = (PlaceAutocompleteFragment)getActivity().
getFragmentManager().findFragmentById(R.id.place_autocomplete_fragment);
autocompleteFragment.setOnPlaceSelectedListener(new PlaceSelectionListener() {
#Override
public void onPlaceSelected(Place place) {
mapview.getMapAsync(instance);
}
#Override
public void onError(Status status) {
Log.e("Error", status.getStatusMessage());
}
});
}
And don't forget to update your onCreateView with the new function signature as the following:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_googlemaptab, container, false);
kakaobutton = (Button)view.findViewById(R.id.kakaobutton);
mapview = (MapView)view.findViewById(R.id.google_map_view);
setupAutoCompleteFragment(this);
return view;
}

You can use Classname.this in this case.
For example: if your fragment name is HomeFragment then,
HomeFragment.this
If this still doesn't work then you can override onViewCreated() function and call mapView.getMapAsync(this) inside onViewCreated()
If needed check this link

have you tried with mapview.getMapAsync(getActivity()); instead of mapview.getMapAsync(this);

How to Access Activity(except mainactivity) from Fragment?

I created my test project where i code to communicate between two fragments but actully I want to access activity from fragment.
Here is code to connect fragment to fragment, its working absolutely right without any error but now i want to change this code to connect activity from fragment instead of fragment to fragment communication.
So Please change this code to access activities from fragment. I stuck on this issue for than a week.So Guys please resolve this.
here is my mainaactivity:
public class MainActivity extends AppCompatActivity implements FragmentA.FragmentAListener, FragmentB.FragmentBListener {
private FragmentA fragmentA;
private FragmentB fragmentB;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
fragmentA = new FragmentA();
fragmentB = new FragmentB();
getSupportFragmentManager().beginTransaction()
.replace(R.id.container_a, fragmentA)
.replace(R.id.container_b, fragmentB)
.commit();
}
#Override
public void onInputASent(CharSequence input) {
fragmentB.updateEditText(input);
}
#Override
public void onInputBSent(CharSequence input) {
fragmentA.updateEditText(input);
}
Here is my FragmentA.java:
public class FragmentA extends Fragment {
private FragmentAListener listener;
private EditText editText;
private Button buttonOk;
public interface FragmentAListener {
void onInputASent(CharSequence input);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_a, container, false);
editText = v.findViewById(R.id.edit_text);
buttonOk = v.findViewById(R.id.button_ok);
buttonOk.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
CharSequence input = editText.getText();
listener.onInputASent(input);
}
});
return v;
}
public void updateEditText(CharSequence newText) {
editText.setText(newText);
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof FragmentAListener) {
listener = (FragmentAListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement FragmentAListener");
}
}
#Override
public void onDetach() {
super.onDetach();
listener = null;
}
}
Here is my FragmentB.java:
public class FragmentB extends Fragment {
private FragmentBListener listener;
private EditText editText;
private Button buttonOk;
public interface FragmentBListener {
void onInputBSent(CharSequence input);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_b, container, false);
editText = v.findViewById(R.id.edit_text);
buttonOk = v.findViewById(R.id.button_ok);
buttonOk.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
CharSequence input = editText.getText();
listener.onInputBSent(input);
}
});
return v;
}
public void updateEditText(CharSequence newText) {
editText.setText(newText);
}
#Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof FragmentBListener) {
listener = (FragmentBListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement FragmentBListener");
}
}
#Override
public void onDetach() {
super.onDetach();
listener = null;
}
}
Here is my Fertilizers.java file which i want to access from FragmentA.:
public class Fertilizers extends AppCompatActivity {
RecyclerView mRecyclerView;
List<FertilizerData> myFertilizersList;
FertilizerData mFertilizersData;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fertilizers);
mRecyclerView = (RecyclerView)findViewById(R.id.recyclerView);
GridLayoutManager gridLayoutManager;
gridLayoutManager = new GridLayoutManager(Fertilizers.this, 1);
mRecyclerView.setLayoutManager(gridLayoutManager);
myFertilizersList = new ArrayList<>();
mFertilizersData = new FertilizerData("Urea Fertilizer","Urea is a concent","Rs.1900",R.drawable.urea);
myFertilizersList.add(mFertilizersData);
myFertilizersList.add(mFertilizersData); }
}
please write here a block of code to call Fertilzers Activity from FragmentA, I,ll be very thankful to you.

Calling getActivity() in your fragment gives you the calling activity so if MainActivity started your fragment then you would do
(MainActivity(getActivity())).something_from_your_main_activity

Solution found by itself regarding this issue.
FragmentHome.java class should look like this:
public class FragmentHome extends Fragment {
private Button button;
public FragmentHome(){
}
public interface OnMessageReadListener
{
public void onMessageRead(String message);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_home, container, false);
button = (Button)v.findViewById(R.id.bn);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getActivity(), Fertilizers.class);
intent.putExtra("some"," some data");
startActivity(intent);
}
});
return v;
}
}
FertilizersActivity.java should look like this:
public class Fertilizers extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fertilizers);
Bundle bundle = getIntent().getExtras();
if (bundle != null){
if(bundle.getStringArrayList("some") !=null){
Toast.makeText(getApplicationContext(),"data:" + bundle.getStringArrayList("some"),Toast.LENGTH_LONG).show();
}
}
}
}

Handling Multiple Fragments when orientation changes

I have a MainActivity, and I want to attach a fragment with 3 buttons in it to that activity. On clicking button 1 it should replace this fragment with another fragment. But when I change orientation the current fragment and the old fragment are both getting attached. Can someone help me solve this ?
Following is my MainActivity.java:
public class MainActivity extends AppCompatActivity implements OnButtonsClickListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getSupportFragmentManager().beginTransaction()
.add(R.id.mainactivity, new FragmentHomepage(), "aboutMe")
.commit();
}
#Override
public void button1Action() {
FragmentAboutMe fragmentAboutMe=new FragmentAboutMe();
getSupportFragmentManager().beginTransaction()
.add(R.id.mainactivity,fragmentAboutMe)
.commit();
}
#Override
public void button2Action() {
Intent intent =new Intent(this,ActivityMasterDetail.class);
startActivity(intent);
}
#Override
public void button3Action() {
Intent intent =new Intent(this,ActivityViewPager.class);
startActivity(intent);
}
}
This is my FragmentHomepage.java:
public class FragmentHomepage extends Fragment {
private static final String ARG_SECTION_NUMBER ="section number";
OnButtonsClickListener onButtonsClickListener;
public static FragmentHomepage newInstance(int sectionNumber){
FragmentHomepage fragmentHomepage=new FragmentHomepage();
Bundle args=new Bundle();
args.putInt(ARG_SECTION_NUMBER,sectionNumber);
fragmentHomepage.setArguments(args);
return fragmentHomepage;
}
public FragmentHomepage(){}
#Override
public void onAttach(Context context) {
super.onAttach(context);
try {
onButtonsClickListener= (OnButtonsClickListener) context;
} catch (Exception e) {
e.printStackTrace();
}
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
final Button button1= (Button) getActivity().findViewById(R.id.aboutMe);
final Button button2= (Button) getActivity().findViewById(R.id.task2);
final Button button3= (Button) getActivity().findViewById(R.id.task3);
button1.setOnClickListener(new Button.OnClickListener() {
#Override
public void onClick(View v) {
onButtonsClickListener.button1Action();
}
});
button2.setOnClickListener(new Button.OnClickListener() {
#Override
public void onClick(View v) {
onButtonsClickListener.button2Action();
}
});
button3.setOnClickListener(new Button.OnClickListener() {
#Override
public void onClick(View v) {
onButtonsClickListener.button3Action();
}
});
}
#Nullable
#Override
public View onCreateView(final LayoutInflater inflater,
ViewGroup container,
Bundle savedInstanceState) {
View rootView=null;
rootView =inflater.inflate(R.layout.fragment_homepage,container,false);
return rootView;
}
}
and my second activity is as follows
(in FragmentAboutMe.java):
public class FragmentAboutMe extends Fragment {
int counters=0;
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if(savedInstanceState==null)counters=0;
else counters=savedInstanceState.getInt("count");
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt("count",13);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater,
ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_aboutme,container,false);
}
}

In your onCreate() method put a check whether the fragment is already present. Android automatically restores the fragment manager state upon orientation change and hence upon orientation change, the fragment which you added on button click would automatically be added. Thus if you will add new fragment in onCreate() without check, this would result in adding the 2 fragments. This is causing the issue.
FragmentManager fm = getSupportFragmentManager();
if (fm.findfragmentById(R.id.mainactivity) == null) {
FragmentHomepage fragment = new FragmentHomepage ();
fm.beginTransaction().add (R.id.mainactivity, fragment).commit();
}

You would want to save the state. You would need to extend Fragment to store the objects that need saving.
Override the onConfigurationChanged(..) and it should work out.
When I had to handle screen orientation changes, I recall having used this reference [link].

There are two ways.
Either you need to save the state in the bundle in onSaveInstanceState() method. Also save the states of fragment.
When activity recreate itself then check the value of bundle inside onCreate() or onRestoreInstanceState() method. Now initialize all the objects as before.
Else
set the value of activity inside manifest file as
android:configChanges="layoutDirection|orientation|screenLayout|screenSize"
and override the method.
#Override
public void onConfigurationChanged(Configuration newConfig) {
}
Second technique will not allow the activity to restart on orientation change.

Could not dispatch Event error

I am new in android and working on app.help me in this.My Log is here
Could not dispatch event: class com.shalom.shalombase.event.RequestPurchaseEvent to handler [EventHandler public void com.shalom.shalombase.activity.MainActivity.onRequestPurchaseEvent(com.shalom.shalombase.event.RequestPurchaseEvent)]: null
at com.squareup.otto.Bus.throwRuntimeException(Bus.java:456)
at com.squareup.otto.Bus.dispatch(Bus.java:386)
at com.squareup.otto.Bus.dispatchQueuedEvents(Bus.java:367)
at com.squareup.otto.Bus.post(Bus.java:336)
Myfragment subcriptionfragment that is posting event to main activity.
public class SubscribeFragment extends ShalomBaseFragment {
private Button subscribeLayout;
private LinearLayout subscribebuttonslayout;
private FrameLayout sampleframe;
private RelativeLayout subscribelayout;
View progressLayout;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.subscribe_layout, container, false);
}
#Subscribe
public void onStoreProgressEvent (StoreProgressEvent event) {
if(event!=null&&progressLayout!=null)
{
if(event.isInProgress)
progressLayout.setVisibility(View.VISIBLE);
else
progressLayout.setVisibility(View.GONE);
}
}
#Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
initialize(view);
subscribebuttonslayout.setVisibility(View.VISIBLE);
subscribelayout.setVisibility(View.VISIBLE);
subscribeLayout.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
bus.post(new RequestPurchaseEvent(BaseConstants.YEARLY_SUBSCRIPTION));
}
});
getChildFragmentManager().beginTransaction()
.replace(R.id.sample_frame, new LibrarySamleIssueFragment())
.commit();
}
private void initialize(View view) {
subscribeLayout = (Button) view.findViewById(R.id.button1);
subscribebuttonslayout = (LinearLayout) view.findViewById(R.id.subscribe_buttons_layout);
sampleframe = (FrameLayout) view.findViewById(R.id.sample_frame);
progressLayout = (View) view.findViewById(R.id.progress_layout);
subscribelayout = (RelativeLayout) view.findViewById(R.id.subscribe_layout);
}
}
Please help me in this.It is working fine on S3, but it is creating issue on Nexus7.
I dont what is the problem with code.I am confused in this

otto code :
method.invoke(target, event);
the next operation is：
#Subscribe
public void yourMethod(Event event) {
//your code throw exception
}
your Method throw exception catched by otto
so, this is my condition.