Я пытаюсь сохранить свой ArrayList элементов ArrayList<MyItem> items через Gson. Но когда я снова открываю приложение, все исчезает, и данные не загружаются.
Это мой код (я использую фрагменты)
public class FragmentPage extends Fragment {
private ExampleAdapter mAdapter;
private EditText editTask;
ArrayList<MyItem> items;
private Button insertbtn;
private Button stateButton;
private TextView taskText;
private String task;
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable
Bundle savedInstanceState) {
loadData();
CreateExampleList();
View view = inflater.inflate(R.layout.page_fragment, container, false);
RecyclerView recyclerView = view.findViewById(R.id.listRecyclerView);
taskText = view.findViewById(R.id.tv_country);
insertbtn = view.findViewById(R.id.button_insert);
editTask = view.findViewById(R.id.editTask);
stateButton = view.findViewById(R.id.tv_button);
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);
}
});
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);
return view;
}
private void SaveData() {
SharedPreferences sharedPreferences = this.getActivity().getSharedPreferences("shared
preferences", 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
preferences", 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, stateButton));
mAdapter.notifyItemInserted(items.size());
}
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());
}
};
}