please help, When i tried same code with same model classes this code run perfectly but it will take many time to connect with firebase app crashed multiple time then connect once but after connecting app run successfully until I change the databasereference name or remove by mistake.....Is is happen every time or just with me????
06-22 08:54:46.182 16552-16552/sszj_capricorn.pricecontrolists E/AndroidRuntime: FATAL EXCEPTION: main
Process: sszj_capricorn.pricecontrolists, PID: 16552
java.lang.NoSuchMethodError: com.google.firebase.FirebaseApp.zzNU
at com.google.firebase.database.FirebaseDatabase.getInstance(Unknown Source)
at com.google.firebase.database.FirebaseDatabase.getInstance(Unknown Source)
at sszj_capricorn.pricecontrolists.Controller.MainActivity.onCreate(MainActivity.java:44)
at android.app.Activity.performCreate(Activity.java:5275)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2166)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2252)
at android.app.ActivityThread.access$800(ActivityThread.java:139)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1200)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5103)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:606)
at dalvik.system.NativeStart.main(Native Method)
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
FirebaseDatabase database;
DatabaseReference myRef;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
PhotoView photoView = (PhotoView) findViewById(R.id.imageView);
mRecyclerView = (RecyclerView) findViewById(R.id.rv);
mRecyclerView.setHasFixedSize(true);
// mLayoutManager=new LinearLayoutManager(this);
//mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
FirebaseDatabase.getInstance().setPersistenceEnabled(true);
database = FirebaseDatabase.getInstance();
myRef = database.getReference("Veg");
}
public void onStart() {
super.onStart();
FirebaseRecyclerAdapter<ModelClass, MainActivity.BlogViewHolder> firebaseRecyclerAdapter =
new FirebaseRecyclerAdapter<ModelClass, MainActivity.BlogViewHolder>(ModelClass.class, R.layout.design_row, MainActivity.BlogViewHolder.class, myRef) {
#Override
protected void populateViewHolder(MainActivity.BlogViewHolder viewHolder, ModelClass model, int position) {
viewHolder.setTitle(model.gettitle());
viewHolder.setImage(getApplicationContext(), model.getImage());
}
};
mRecyclerView.setAdapter(firebaseRecyclerAdapter);
}
public static class BlogViewHolder extends RecyclerView.ViewHolder {
View mView;
public BlogViewHolder(View itemView) {
super(itemView);
mView = itemView;
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent browserIntent = new Intent(Intent.ACTION_VIEW,
Uri.parse("https://price-control-list-fca08.firebaseio.com/"));
Intent browserChooserIntent = Intent.createChooser(browserIntent, "Soghat");
v.getContext().startActivity(browserChooserIntent);
}
});
}
public void setTitle(String title) {
TextView post_title = (TextView) mView.findViewById(R.id.titleText);
post_title.setText(title);
}
public void setImage(Context ctx, String image) {
ImageView post_image = (ImageView) mView.findViewById(R.id.imageView);
Picasso.with(ctx).load(image).into(post_image);
}
}
}
Related
I have an updateTask method which opens an alert dialog. I am trying to call this method through a listener in the onBindViewHolder function in my custom adapter.
However my alert dialog does not pop up and while debugging I found out that my update task method is not called.
Please help me understand why.
Thanks
Here is my customAdapter:
public class TasksAdapter extends RecyclerView.Adapter<TasksAdapter.TaskViewHolder> {
private ArrayList<Model> tasks;
private TaskUpdateListener listener;
TasksAdapter(ArrayList<Model> tasks,TaskUpdateListener listener) {
this.tasks = tasks;
this.listener = listener;
}
#Override
public TaskViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.retrieved_layout, parent, false);
return new TaskViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull TaskViewHolder holder, int position) {
Model task = tasks.get(position);
holder.setDate(task.getDate());
holder.setTask(task.getTask());
holder.setDesc(task.getDescription());
holder.mView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String taskString = task.getTask();
String descString = task.getDescription();
listener.onTaskUpdate(task, position);
}
});
}
#Override
public int getItemCount() {
return tasks.size();
}
public static class TaskViewHolder extends RecyclerView.ViewHolder {
View mView;
public TaskViewHolder(#NonNull View itemView) {
super(itemView);
mView = itemView;
}
public void setTask(String task) {
TextView taskTextView = mView.findViewById(R.id.taskTv);
taskTextView.setText(task);
}
public void setDesc(String desc) {
TextView descTextView = mView.findViewById(R.id.descriptionTv);
descTextView.setText(desc);
}
public void setDate(String date) {
TextView dateTextView = mView.findViewById(R.id.dateTv);
}
}
public interface TaskUpdateListener {
void onTaskUpdate(Model model, int position);
}
}
And here is my HomeActivity:
public class HomeActivity extends AppCompatActivity {
private Toolbar toolbar;
private RecyclerView recyclerView;
private FloatingActionButton floatingActionButton;
private FirebaseDatabase database = FirebaseDatabase.getInstance();
private DatabaseReference userTasksRef;
private FirebaseAuth mAuth;
private FirebaseUser mUser;
private String onlineUserID;
private ProgressDialog loader;
private String key = "";
private String task;
private String description;
#Override
public void onBackPressed(){
new AlertDialog.Builder(this)
.setMessage("Are you sure you want exit ?")
.setCancelable(false)
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
finish();
}
})
.setNegativeButton("No", null)
.show();
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_home);
toolbar = findViewById(R.id.homeToolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setTitle("Todo List App");
mAuth = FirebaseAuth.getInstance();
recyclerView = findViewById(R.id.recyclerView);
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
linearLayoutManager.setReverseLayout(true);
linearLayoutManager.setStackFromEnd(true);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(linearLayoutManager);
loader = new ProgressDialog(this);
mUser = mAuth.getCurrentUser();
onlineUserID = mUser.getUid();
database = FirebaseDatabase.getInstance("https://todolist-bbccd-default-rtdb.europe-west1.firebasedatabase.app");
userTasksRef = database.getReference("users").child(onlineUserID).child("tasks");
floatingActionButton = findViewById(R.id.fab);
floatingActionButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
addTask();
}
});
}
private void addTask() {
AlertDialog.Builder myDialog = new AlertDialog.Builder(this);
LayoutInflater inflater = LayoutInflater.from(this);
View myView = inflater.inflate(R.layout.input_file, null);
myDialog.setView(myView);
final AlertDialog dialog = myDialog.create();
dialog.setCancelable(false);
final EditText task = myView.findViewById(R.id.task);
final EditText description = myView.findViewById(R.id.description);
Button save = myView.findViewById(R.id.saveBtn);
Button cancel = myView.findViewById(R.id.CancelBtn);
cancel.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
dialog.dismiss();
}
});
save.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String mTask = task.getText().toString().trim();
String mDescription = description.getText().toString().trim();
String id = userTasksRef.push().getKey();
String date = DateFormat.getDateInstance().format(new Date());
if (TextUtils.isEmpty(mTask)) {
task.setError("Task Required");
return;
}
if (TextUtils.isEmpty(mDescription)) {
description.setError("Description Required");
return;
} else {
loader.setMessage("Adding your data");
loader.setCanceledOnTouchOutside(false);
loader.show();
Model model = new Model(mTask, mDescription, id, date);
userTasksRef.child(id).setValue(model).addOnCompleteListener(new OnCompleteListener<Void>() {
#Override
public void onComplete(#NonNull Task<Void> task) {
if (task.isSuccessful()) {
Toast.makeText(HomeActivity.this, "Task has been inserted successfully", Toast.LENGTH_SHORT).show();
loader.dismiss();
} else {
String error = task.getException().toString();
Toast.makeText(HomeActivity.this, "Failed: " + error, Toast.LENGTH_SHORT).show();
loader.dismiss();
}
}
});
}
dialog.dismiss();
}
});
dialog.show();
}
#Override
protected void onStart() {
super.onStart();
ArrayList<Model> tasks = new ArrayList<>();
userTasksRef.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(#NonNull DataSnapshot dataSnapshot) {
for (DataSnapshot taskSnapshot : dataSnapshot.getChildren()) {
Model task = taskSnapshot.getValue(Model.class);
tasks.add(task);
}
}
#Override
public void onCancelled(#NonNull DatabaseError databaseError) {
// Handle errors here
}
});
TasksAdapter.TaskUpdateListener listener = new TasksAdapter.TaskUpdateListener() {
#Override
public void onTaskUpdate(Model model, int position) {
updateTask(model, position);
}
};
TasksAdapter adapter = new TasksAdapter(tasks, listener);
recyclerView.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
public void updateTask(Model task, final int position ) {
AlertDialog.Builder myDialog = new AlertDialog.Builder(this);
LayoutInflater inflater = LayoutInflater.from(this);
View view = inflater.inflate(R.layout.update_data, null);
myDialog.setView(view);
final AlertDialog dialog = myDialog.create();
final EditText mTask = view.findViewById(R.id.mEditTextTask);
final EditText mDescription = view.findViewById(R.id.mEditTextDescription);
mTask.setText(task.getTask());
mTask.setSelection(task.getTask().length());
mDescription.setText(task.getDescription());
mDescription.setSelection(task.getDescription().length());
Button delButton = view.findViewById(R.id.btnDelete);
Button updateButton = view.findViewById(R.id.btnUpdate);
updateButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String tasktxt = mTask.getText().toString().trim();
String descriptiontxt = mDescription.getText().toString().trim();
String date = DateFormat.getDateInstance().format(new Date());
Model model = new Model(tasktxt, descriptiontxt, key, date);
userTasksRef.child(key).setValue(model).addOnCompleteListener(new OnCompleteListener<Void>() {
#Override
public void onComplete(#NonNull Task<Void> task) {
if (task.isSuccessful()){
Toast.makeText(HomeActivity.this, "Data has been updated successfully", Toast.LENGTH_SHORT).show();
}else {
String err = task.getException().toString();
Toast.makeText(HomeActivity.this, "update failed "+err, Toast.LENGTH_SHORT).show();
}
}
});
dialog.dismiss();
}
});
}
}
Attempt to invoke interface method 'void com.example.imovie.adapter.MovieItemClickListener.onMovieClick(com.example.imovie.models.Movie, android.widget.ImageView)' on a null object reference
public class MovieAdapter extends RecyclerView.Adapter<MovieAdapter.MyViewHolder> {
Context context ;
List<Movie> mData;
MovieItemClickListener movieItemClickListener;
public MovieAdapter(Context context, List<Movie> mData, MovieItemClickListener listener) {
this.context = context;
this.mData = mData;
movieItemClickListener = listener;
}
#NonNull
#Override
public MyViewHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(context).inflate(R.layout.item_movie,viewGroup,false);
return new MyViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull MyViewHolder myViewHolder, int i) {
myViewHolder.TvTitle.setText(mData.get(i).getTitle());
myViewHolder.ImgMovie.setImageResource(mData.get(i).getThumbnail());
}
#Override
public int getItemCount() {
return mData.size();
}
public class MyViewHolder extends RecyclerView.ViewHolder {
private TextView TvTitle;
private ImageView ImgMovie;
public MyViewHolder(#NonNull View itemView) {
super(itemView);
TvTitle = itemView.findViewById(R.id.item_movie_title);
ImgMovie = itemView.findViewById(R.id.item_movie_img);
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
movieItemClickListener.onMovieClick(mData.get(getAdapterPosition()),ImgMovie);//i have a null object reference
}
});
}
}
}
public class HomeFragment extends Fragment implements MovieItemClickListener {
private HomeViewModel homeViewModel;
private List<Slide> listSlides;
private ViewPager slidePager;
private TabLayout indicator;
private RecyclerView moviesRV;
private RecyclerView moviesRV2;
private MovieItemClickListener movieItemClickListener;
public View onCreateView(#NonNull LayoutInflater inflater,
ViewGroup container, Bundle savedInstanceState) {
homeViewModel =
ViewModelProviders.of(this).get(HomeViewModel.class);
View root = inflater.inflate(R.layout.fragment_home, container, false);
slidePager = root.findViewById(R.id.slider_pager);
indicator = root.findViewById(R.id.indicator);
moviesRV = root.findViewById(R.id.rsViewMovies);
moviesRV2 = root.findViewById(R.id.rsViewMovies2);
iniSlider();
final SliderPagerAdapter sliderPagerAdapteradapter = new SliderPagerAdapter(getContext(), listSlides);
final MovieAdapter movieAdapter = new MovieAdapter(getContext(), DateSource.getPopularMovies(), movieItemClickListener);
final Timer timer = new Timer();
timer.scheduleAtFixedRate(new SliderTimer(), 4000, 6000);
homeViewModel.getText().observe(this, new Observer<String>() {
#Override
public void onChanged(#Nullable String s) {
slidePager.setAdapter(sliderPagerAdapteradapter);
indicator.setupWithViewPager(slidePager, true);
moviesRV.setAdapter(movieAdapter);
moviesRV.setLayoutManager(new LinearLayoutManager(getContext(), LinearLayoutManager.HORIZONTAL, false));
moviesRV2.setAdapter(movieAdapter);
moviesRV2.setLayoutManager(new LinearLayoutManager(getContext(), LinearLayoutManager.HORIZONTAL, false));
}
});
return root;
}
#Override
public void onMovieClick(Movie movie, ImageView imageView) {
Intent intent = new Intent(getContext(), MovieDetailActivity.class);
intent.putExtra("title", movie.getTitle());
intent.putExtra("imgURL", movie.getThumbnail());
intent.putExtra("imgCover", movie.getCoverPhoto());
ActivityOptions options = ActivityOptions.makeSceneTransitionAnimation(getActivity(),
imageView, "sharedName");
startActivity(intent, options.toBundle());
Toast.makeText(getContext(), "item clicked : " + movie.getTitle(), Toast.LENGTH_LONG).show();
}
class SliderTimer extends TimerTask {
#Override
public void run() {
if (getActivity() != null) {
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
if (slidePager.getCurrentItem() < listSlides.size() - 1) {
slidePager.setCurrentItem(slidePager.getCurrentItem() + 1);
} else {
slidePager.setCurrentItem(0);
}
}
});
}
}
}
private void iniSlider() {
listSlides = new ArrayList<>();
listSlides.add(new Slide(R.drawable.a, "slide title \n movie title"));
listSlides.add(new Slide(R.drawable.b, "slide title"));
listSlides.add(new Slide(R.drawable.a, "slide title \n movie title"));
listSlides.add(new Slide(R.drawable.b, "slide title"));
}
}
If I'm not wrong, HomeFragment.movieItemClickListener is never initialized.
You may want to make the following changes in HomeFragment:
1. Delete the line
private MovieItemClickListener movieItemClickListener;
2. In this line
final MovieAdapter movieAdapter = new MovieAdapter(getContext(), DateSource.getPopularMovies(), movieItemClickListener);
change movieItemClickListener to this, because HomeFragment implements MovieItemClickListener.
That should fix the NullPointerException.
I am getting compile error in line .addOnCompleteListener(LoginActivity.this : Login Activity is not an enclosed class.
Am I doing anything wrong in below code?
Below is my code in Activity
public class LoginFirebase extends AppCompatActivity {
private FirebaseAuth auth;
Button btn_Login;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login_firebase);
btn_Login = (Button) findViewById(R.id.btn_Login);
btn_Login.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(final View view) {
auth.signInWithEmailAndPassword("username", "password")
.addOnCompleteListener(LoginActivity.this, new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
}
})
}
});
}
}
Please replace LoginActivity to LoginFirebase .
This mqtt subscriber code works fine. I can easily subscribe to messages which are published at broker.hivemq.com with respective topic.
public class AccelerometerSubscriber implements MqttCallback,
IMqttActionListener {
public static void main(String[] args) throws MqttException {
int QUALITY_OF_SERVICE = 2;
MqttClient client=new MqttClient("tcp://broker.hivemq.com:1883",
MqttClient.generateClientId());
client.setCallback( new SimpleMqttCallBack() );
client.connect();
System.out.println("Subscribing ....");
client.subscribe("MQTT Examples"); }
System.out.println("some action"); //------------right here--------------
public void connectionLost(Throwable throwable) {
System.out.println("Connection to MQTT broker lost!"); }
public void messageArrived(String s, MqttMessage mqttMessage) throws Exception {
System.out.println("Message received:\n\t"+ new String(mqttMessage.getPayload()) );
}
public void deliveryComplete(IMqttDeliveryToken iMqttDeliveryToken) {
// not used in this example
}}
Now I want to perform action only when a message is received. I'm unable to do that.
You have a class (AccelerometerSubscriber) that implements the interface MqttCallback, use an instance of it instead of doing client.setCallback( new SimpleMqttCallBack() );
public class AccelerometerSubscriber implements MqttCallback, IMqttActionListener {
public static void main(String[] args) throws MqttException {
AccelerometerSubscriber as = new AccelerometerSubscriber();
int QUALITY_OF_SERVICE = 2;
MqttClient client = new MqttClient("tcp://broker.hivemq.com:1883", MqttClient.generateClientId());
client.setCallback(as);
client.connect();
System.out.println("Subscribing ....");
client.subscribe("MQTT Examples");
}
#Override
public void connectionLost(Throwable throwable) {
System.out.println("Connection to MQTT broker lost!");
}
#Override
public void messageArrived(String s, MqttMessage mqttMessage) throws Exception {
//message is received is here!!!
System.out.println("Message received:\n\t" + new String(mqttMessage.getPayload()));
}
#Override
public void deliveryComplete(IMqttDeliveryToken iMqttDeliveryToken) {
System.out.println("deliveryComplete");
}
#Override
public void onFailure(IMqttToken arg0, Throwable arg1) {
System.out.println("onFailure");
}
#Override
public void onSuccess(IMqttToken arg0) {
System.out.println("onSuccess");
}
}
I'm using trying to use a javafx combobox with a cell factory to render the list, I was using the setText on the override updateItem() of my CellList, but I found out when I change a value on the underlying model, that doesnẗ afects the deployed list on the combo box. So I try to make it binding both properties and It's works but when a try to clear the selection I have a Exception. This is the code:
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.Stage;
import javafx.util.Callback;
public class BasicComboBoxSample extends Application {
public static void main(String[] args) { launch(args); }
#Override public void start(Stage stage) {
final Employee john = new Employee("John");
final Employee jill = new Employee("Jill");
final Employee jack = new Employee("Jack");
final ComboBox<Employee> cboEmployees = new ComboBox();
cboEmployees.getItems().addAll(john, jill, jack);
cboEmployees.setValue(jill);
Button b = new Button("ChangeName");
b.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent actionEvent) {
john.setName("Maria");
}
});
Button c = new Button("Clear");
c.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent actionEvent) {
cboEmployees.getSelectionModel().clearSelection();
}
});
Button d = new Button("Select First");
d.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent actionEvent) {
cboEmployees.getSelectionModel().select(john);
}
});
Callback<ListView<Employee>, ListCell<Employee>> cellFactory = new Callback<ListView<Employee>, ListCell<Employee>>() {
#Override
public ListCell<Employee> call(ListView<Employee> listView) {
return new EmployeeListCell(); //To change body of implemented methods use File | Settings | File Templates.
}
};
cboEmployees.setButtonCell(new EmployeeListCell());
cboEmployees.setCellFactory(cellFactory);
final StackPane layout = new StackPane();
VBox v = new VBox();
v.getChildren().add(cboEmployees);
v.getChildren().add(b);
v.getChildren().add(c);
v.getChildren().add(d);
layout.getChildren().add(v);
layout.setStyle("-fx-background-color: cornsilk; -fx-padding: 15;");
stage.setScene(new Scene(layout));
stage.show();
}
class Employee {
public Employee(String name) { this.setName(name); }
private SimpleStringProperty name = new SimpleStringProperty("");
String getName() {
return name.get();
}
SimpleStringProperty nameProperty() {
return name;
}
void setName(String name) {
this.name.set(name);
}
}
public class EmployeeListCell extends ListCell<Employee> {
#Override
protected void updateItem(Employee emp, boolean b) {
super.updateItem(emp, b);
if(emp != null){
textProperty().bind(emp.nameProperty());
}
}
}
}
And the Exception was:
Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: A bound value cannot be set.
at javafx.beans.property.StringPropertyBase.set(StringPropertyBase.java:157)
at javafx.beans.property.StringPropertyBase.set(StringPropertyBase.java:67)
at javafx.beans.property.StringProperty.setValue(StringProperty.java:84)
at javafx.scene.control.Labeled.setText(Labeled.java:135)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin.updateDisplayText(ComboBoxListViewSkin.java:420)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin.updateDisplayNode(ComboBoxListViewSkin.java:399)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin.getDisplayNode(ComboBoxListViewSkin.java:229)
at com.sun.javafx.scene.control.skin.ComboBoxBaseSkin.updateDisplayArea(ComboBoxBaseSkin.java:125)
at com.sun.javafx.scene.control.skin.ComboBoxBaseSkin.handleControlPropertyChanged(ComboBoxBaseSkin.java:120)
at com.sun.javafx.scene.control.skin.ComboBoxListViewSkin.handleControlPropertyChanged(ComboBoxListViewSkin.java:198)
at com.sun.javafx.scene.control.skin.SkinBase$3.changed(SkinBase.java:282)
at javafx.beans.value.WeakChangeListener.changed(WeakChangeListener.java:107)
at com.sun.javafx.binding.ExpressionHelper$Generic.fireValueChangedEvent(ExpressionHelper.java:367)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:100)
at javafx.beans.property.ObjectPropertyBase.fireValueChangedEvent(ObjectPropertyBase.java:123)
at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:130)
at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:163)
at javafx.scene.control.ComboBoxBase.setValue(ComboBoxBase.java:148)
at javafx.scene.control.ComboBox.updateValue(ComboBox.java:416)
at javafx.scene.control.ComboBox.access$300(ComboBox.java:166)
at javafx.scene.control.ComboBox$6.changed(ComboBox.java:401)
at com.sun.javafx.binding.ExpressionHelper$Generic.fireValueChangedEvent(ExpressionHelper.java:367)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:100)
at javafx.beans.property.ReadOnlyObjectWrapper$ReadOnlyPropertyImpl.fireValueChangedEvent(ReadOnlyObjectWrapper.java:195)
at javafx.beans.property.ReadOnlyObjectWrapper.fireValueChangedEvent(ReadOnlyObjectWrapper.java:161)
at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:130)
at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:163)
at javafx.scene.control.SelectionModel.setSelectedItem(SelectionModel.java:101)
at javafx.scene.control.ComboBox$ComboBoxSelectionModel$1.invalidated(ComboBox.java:448)
at com.sun.javafx.binding.ExpressionHelper$SingleInvalidation.fireValueChangedEvent(ExpressionHelper.java:155)
at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:100)
at javafx.beans.property.ReadOnlyIntegerWrapper$ReadOnlyPropertyImpl.fireValueChangedEvent(ReadOnlyIntegerWrapper.java:195)
at javafx.beans.property.ReadOnlyIntegerWrapper.fireValueChangedEvent(ReadOnlyIntegerWrapper.java:161)
at javafx.beans.property.IntegerPropertyBase.markInvalid(IntegerPropertyBase.java:130)
at javafx.beans.property.IntegerPropertyBase.set(IntegerPropertyBase.java:163)
at javafx.scene.control.SelectionModel.setSelectedIndex(SelectionModel.java:67)
at javafx.scene.control.SingleSelectionModel.updateSelectedIndex(SingleSelectionModel.java:208)
at javafx.scene.control.SingleSelectionModel.clearSelection(SingleSelectionModel.java:67)
at de.thomasbolz.javafx.BasicComboBoxSample$2.handle(BasicComboBoxSample.java:45)
at de.thomasbolz.javafx.BasicComboBoxSample$2.handle(BasicComboBoxSample.java:42)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:69)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:217)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:170)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:38)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:37)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:53)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:28)
at javafx.event.Event.fireEvent(Event.java:171)
at javafx.scene.Node.fireEvent(Node.java:6863)
at javafx.scene.control.Button.fire(Button.java:179)
at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:193)
at com.sun.javafx.scene.control.skin.SkinBase$4.handle(SkinBase.java:336)
at com.sun.javafx.scene.control.skin.SkinBase$4.handle(SkinBase.java:329)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:64)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:217)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:170)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:38)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:37)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:53)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:33)
at javafx.event.Event.fireEvent(Event.java:171)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3328)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3168)
at javafx.scene.Scene$MouseHandler.access$1900(Scene.java:3123)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1563)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2265)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:250)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:173)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:292)
at com.sun.glass.ui.View.handleMouseEvent(View.java:528)
at com.sun.glass.ui.View.notifyMouse(View.java:922)
at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method)
at com.sun.glass.ui.gtk.GtkApplication$3$1.run(GtkApplication.java:82)
at java.lang.Thread.run(Thread.java:722)
You need to unbind the textProperty in case the emp is null
Add the condition in EmployeeListCell class
else {
textProperty().unbind();
}