Я пытаюсь сохранить данные моего EditText topic автоматически после его изменения, но я получаю вот этот logcat
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.EditText.setText(java.lang.CharSequence)' on a null object reference
at com.example.barryblack.FragmentPage0.onCreateView(FragmentPage0.java:68)
Итак, вот код проблемы
final SharedPreferences prefs = PreferenceManager
.getDefaultSharedPreferences(this.getActivity());
topic = view.findViewById(R.id.topicText0);
topic.setText(prefs.getString("autosave", ""));
topic.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
@Override
public void afterTextChanged(Editable s) {
prefs.edit().putString("autosave", s.toString()).apply();
}
});
И это весь мой код, если необходимо (loadData() и SaveDate() - метод, который я сделал для сохранения ArarayList, но не имеет ничего общего с моей проблемой)
package com.example.barryblack;
public class FragmentPage0 extends Fragment {
private ExampleAdapter mAdapter;
private EditText editTask;
private Button insertbtn;
private TextView taskText;
private String task;
Context context;
ArrayList<MyItem> items;
private static final String SHARED_PREFS_FRAGMENT_A = "fragmentA";
private EditText topic;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable
ViewGroup container, @Nullable Bundle savedInstanceState) {
CreateExampleList();
View view = inflater.inflate(R.layout.page_fragment1, container, false);
loadData();
final SharedPreferences prefs = PreferenceManager
.getDefaultSharedPreferences(this.getActivity());
topic = view.findViewById(R.id.topicText0);
topic.setText(prefs.getString("autosave", ""));
topic.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int
count) {
}
@Override
public void afterTextChanged(Editable s) {
prefs.edit().putString("autosave", s.toString()).apply();
}
});
RecyclerView recyclerView = view.findViewById(R.id.listRecyclerView);
recyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager = new
LinearLayoutManager(getActivity());
new
ItemTouchHelper(itemTouchHelperCallback).attachToRecyclerView(recyclerView);
recyclerView.setLayoutManager(layoutManager);
recyclerView.setItemViewCacheSize(500);
mAdapter = new ExampleAdapter(items);
recyclerView.setAdapter(mAdapter);
taskText = view.findViewById(R.id.tv_country);
insertbtn = view.findViewById(R.id.button_insert);
editTask = view.findViewById(R.id.editTask);
context = getActivity();
insertbtn.setEnabled(false);
editTask.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int
count) {
String taskInput = editTask.getText().toString().trim();
insertbtn.setEnabled(!taskInput.isEmpty());
}
@Override
public void afterTextChanged(Editable s) {
task = editTask.getText().toString().trim();
}
});
insertbtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
InsertItem();
SaveData();
editTask.setText(null);
}
});
return view;
}
private void SaveData() {
SharedPreferences sharedPreferences =
this.getActivity().getSharedPreferences(SHARED_PREFS_FRAGMENT_A,
MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
Gson gson = new Gson();
String json = gson.toJson(items);
editor.putString("task list", json);
editor.apply();
}
private void loadData() {
SharedPreferences sharedPreferences =
this.getActivity().getSharedPreferences(SHARED_PREFS_FRAGMENT_A,
MODE_PRIVATE);
Gson gson = new Gson();
String json = sharedPreferences.getString("task list", null);
Type type = new TypeToken<ArrayList<MyItem>>() {
}.getType();
items = gson.fromJson(json, type);
if (items == null) {
items = new ArrayList();
}
}
public void InsertItem() {
items.add(new MyItem(task));
mAdapter.notifyItemInserted(items.size());
SaveData();
}
private void CreateExampleList() {
items = new ArrayList<MyItem>();
}
ItemTouchHelper.SimpleCallback itemTouchHelperCallback = new
ItemTouchHelper.SimpleCallback(0, ItemTouchHelper.LEFT |
ItemTouchHelper.RIGHT) {
@Override
public boolean onMove(@NonNull RecyclerView recyclerView, @NonNull
RecyclerView.ViewHolder viewHolder, @NonNull RecyclerView.ViewHolder target)
{
return false;
}
@Override
public void onSwiped(@NonNull RecyclerView.ViewHolder viewHolder, int
direction) {
items.remove(viewHolder.getAdapterPosition());
mAdapter.notifyItemRemoved(viewHolder.getAdapterPosition());
SaveData();
}
};
}