Recyclerview 僅顯示 1 項

Question

我的應用程序中有以下代碼，我試圖在過去檢索今天（dd）發生的費用項目，超過 2 次，我想在回收站視圖中填充這些項目。 我得到了預期的結果，但當時只有一項，recyclerview 沒有按預期顯示列表。

我使用實時數據庫。

我正在尋找一些想法，請查看我的代碼；

    //suggestions
    databaseReference.addValueEventListener(new ValueEventListener() {
        @SuppressLint("NotifyDataSetChanged")
        @Override
        public void onDataChange(@NonNull DataSnapshot snapshot) {
            suggestions.clear();
            int occurrences = 0;
            Expense expense1 = new Expense();

            for (DataSnapshot dataSnapshot : snapshot.getChildren()) {
                Expense expense = dataSnapshot.getValue(Expense.class);

                assert expense != null;
                if (expense.getDate().substring(0, 2).equals(day) && expense.getDate().substring(6, 10).equals(year)) {
                    for (Expense e : all_expenses) {
                        if (!today_expenses.contains(e)) {
                            suggestions_title.setVisibility(View.VISIBLE);
                            occurrences = Collections.frequency(all_expenses, e);
                            expense1 = e;
                        }
                    }
                }
            }

            if (occurrences > 2) suggestions.add(expense1);

            suggestionsAdapter.notifyDataSetChanged();

            if (suggestionsAdapter.getItemCount() == 0) {
                suggestions_title.setVisibility(View.INVISIBLE);
            }

        }

        @Override
        public void onCancelled(@NonNull DatabaseError error) {
        }
    });

下面是我的適配器類；

公共類 SuggestionsAdapter 擴展 RecyclerView.Adapter<SuggestionsAdapter.ViewHolder> {

Activity activity;
private final ArrayList<Expense> suggestions;

private String item;
private String category;
private int amount;

FirebaseAuth mAuth;
int totalMonth;

public SuggestionsAdapter(Activity activity, ArrayList<Expense> suggestions) {
    this.activity = activity;
    this.suggestions = suggestions;
}

@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(activity).inflate(R.layout.suggestions, parent, false);

    mAuth = FirebaseAuth.getInstance();
    monthTotalLimit();

    return new ViewHolder(view);
}

@SuppressLint("SetTextI18n")
@Override
public void onBindViewHolder(@NonNull ViewHolder holder, @SuppressLint("RecyclerView") int position) {
    final Expense expense = suggestions.get(position);

    holder.expense.setText("" + expense.getItem());

    holder.add.setOnClickListener(view -> {
        item = expense.getItem();
        category = expense.getCategory();
        amount = expense.getAmount();

        updateExpense();
    });

}

@Override
public int getItemCount() {
    return suggestions.size();
}

public static class ViewHolder extends RecyclerView.ViewHolder {

    private final TextView expense;
    private final TextView add;

    public ViewHolder(@NonNull View itemView) {
        super(itemView);

        expense = itemView.findViewById(R.id.expense);
        add = itemView.findViewById(R.id.add_suggestion);

    }
}

//saving amount for limit check
private void monthTotalLimit() {
    final Calendar c = Calendar.getInstance();
    @SuppressLint("SimpleDateFormat") DateFormat dateFormat = new SimpleDateFormat("MM");
    String month = dateFormat.format(c.getTime());

    DatabaseReference databaseReference = FirebaseDatabase.getInstance().getReference().child("Expenses").child(Objects.requireNonNull(mAuth.getCurrentUser()).getUid());
    databaseReference.addValueEventListener(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot snapshot) {
            int totalAmount = 0;

            for (DataSnapshot ds : snapshot.getChildren()) {
                Expense expense = ds.getValue(Expense.class);

                //dd-MM-yyyy
                assert expense != null;
                if (expense.getDate().substring(3, 5).equals(month)) {
                    totalAmount += expense.getAmount();
                    totalMonth = totalAmount;
                }
            }
        }

        @Override
        public void onCancelled(@NonNull DatabaseError error) {
        }
    });
}

private void updateExpense() {
    DatabaseReference databaseReference = FirebaseDatabase.getInstance().getReference().child("Expenses").child(Objects.requireNonNull(FirebaseAuth.getInstance().getCurrentUser()).getUid());

    AlertDialog.Builder myDialog = new AlertDialog.Builder(activity);
    LayoutInflater inflater = LayoutInflater.from(activity);

    View myView = inflater.inflate(R.layout.input_layout, null);
    myDialog.setView(myView);

    final AlertDialog dialog = myDialog.create();
    dialog.setCancelable(false);

    final EditText mItem = myView.findViewById(R.id.item);
    final TextView mDate = myView.findViewById(R.id.date);
    final EditText mAmount = myView.findViewById(R.id.amount);

    final Calendar c = Calendar.getInstance();
    @SuppressLint("SimpleDateFormat") DateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
    String date = dateFormat.format(c.getTime());

    mItem.setText(item);
    mDate.setText(date);
    mAmount.setText(String.valueOf(amount));

    final Spinner categorySpinner = myView.findViewById(R.id.spinner);

    ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(activity, R.array.Category, android.R.layout.simple_spinner_item);
    adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    categorySpinner.setAdapter(adapter);

    int spinnerPosition = adapter.getPosition(category);
    categorySpinner.setSelection(spinnerPosition);

    final Button cancel_btn = myView.findViewById(R.id.cancel_btn);
    final Button save_btn = myView.findViewById(R.id.save_btn);

    mDate.setOnClickListener(view -> datePicker(mDate));

    save_btn.setOnClickListener(view -> {
        String itemString = mItem.getText().toString();
        String amountString = mAmount.getText().toString();
        String spinnerString = categorySpinner.getSelectedItem().toString();
        String userInputDate = mDate.getText().toString();

        int amountInt;

        if (itemString.isEmpty()) {
            mItem.setError(activity.getString(R.string.name_required));
            mItem.requestFocus();
            return;
        }
        if (amountString.equals("") || amountString.equals("0")) {
            mAmount.setError(activity.getString(R.string.amount_required));
            mAmount.requestFocus();
            return;
        } else {
            amountInt = Integer.parseInt(amountString);
        }
        if ((totalMonth + amountInt) > 2000000000) {
            mAmount.setError(activity.getString(R.string.monthly_limit));
            mAmount.requestFocus();
            return;
        }
        if (spinnerString.equals(activity.getString(R.string.category))) {
            Toast.makeText(activity, R.string.category_required, Toast.LENGTH_SHORT).show();
            return;
        } else {

            String id = databaseReference.push().getKey();

            Expense expense = new Expense(itemString.toUpperCase(Locale.ROOT), spinnerString, userInputDate, id, amountInt);

            assert id != null;
            databaseReference.child(id).setValue(expense).addOnCompleteListener(task -> {
                if (!task.isSuccessful()) {
                    Toast.makeText(activity, activity.getString(R.string.input_error) + task.getException(), Toast.LENGTH_SHORT).show();
                }
            });
        }
        dialog.dismiss();
    });
    cancel_btn.setOnClickListener(view -> dialog.dismiss());

    dialog.show();
}

private void datePicker(TextView textView) {
    Calendar calendar = Calendar.getInstance();

    // Get current time
    int currentYear = calendar.get(Calendar.YEAR);
    int currentMonth = calendar.get(Calendar.MONTH);
    int currentDay = calendar.get(Calendar.DAY_OF_MONTH);

    // Create listener
    @SuppressLint("SetTextI18n") DatePickerDialog.OnDateSetListener listener = (view, year, month, day) -> {

        @SuppressLint("DefaultLocale") String dayS = String.format("%02d", day);
        @SuppressLint("DefaultLocale") String monthS = String.format("%02d", month + 1);

        textView.setText(dayS + "-" + monthS + "-" + year);

    };

    // Move day as today
    calendar.set(Calendar.DAY_OF_MONTH, currentDay);

    // Min = time after changes
    long minTime = calendar.getTimeInMillis();

    // Move day as first day of the month
    calendar.set(Calendar.DAY_OF_MONTH, 1);
    // Move to next month
    calendar.add(Calendar.MONTH, +1);
    // Go back one day (so last day of current month)
    calendar.add(Calendar.DAY_OF_MONTH, -1);

    // Max = current
    long maxTime = calendar.getTimeInMillis();

    // Create dialog
    DatePickerDialog datePickerDialog = new DatePickerDialog(activity,
            listener,
            currentYear,
            currentMonth,
            currentDay);

    // Set dates
    datePickerDialog.getDatePicker().setMinDate(minTime);
    datePickerDialog.getDatePicker().setMaxDate(maxTime);

    // Show dialog
    datePickerDialog.show();
}

}

Answer 1

您的代碼看起來不錯，必須從 firebase 數據庫中獲取多個項目，但整個屏幕上只顯示一個，因為在適配器布局中，父級的高度將是match_parent而不是wrap_content ，這就是為什么一個項目占據了整個屏幕，您看不到其余項目。 如果您甚至垂直滾動屏幕，您也會看到其他項目。 只需將其更改為wrap_content一切都會好起來的:)