How to sort items in RecyclerView depending on a Date

Question

This is what my screen should look like.

I added this library https://github.com/ShamylZakariya/StickyHeaders and tried to do it in similar way.

My model looks like this:

public class Transaction {

private int id;
private Date createdDate;
private String description;
private int amount;
private float newCredits;
}

and

public class Transactions {

private int totalCount;
private List<Transaction> transactions = new ArrayList<>();
}

So after i fetch all my transactions I set the data in adapter.. this is what my adapter looks like:

public class WalletAdapter extends SectioningAdapter {

private static final boolean USE_DEBUG_APPEARANCE = false;

private Transactions transactions;
private List<Section> sections = new ArrayList<>();

public WalletAdapter() {
}

private class Section {
    String alpha;
    Transactions transactions;
}

public Transactions getTransactions() {
    return transactions;
}

public void setTransactions(Transactions transactions) {
    this.transactions = transactions;
    sections.clear();

    char alpha = 0;

    Section currentSection = null;
    for (Transaction transaction : transactions.getTransactions()) {
        String date = parseDate(transaction.getCreatedDate());
        if (date.charAt(0) != alpha) {
            if (currentSection != null) {
                sections.add(currentSection);
            }

            currentSection = new Section();
            alpha = date.charAt(0);
            currentSection.alpha = String.valueOf(alpha);
        }

        if (currentSection != null) {
            currentSection.transactions = this.transactions;
        }
    }

    sections.add(currentSection);
    notifyAllSectionsDataSetChanged();
}

private String parseDate(Date date) {
    DateFormat df = new SimpleDateFormat("dd.MM.yyyy", Locale.getDefault());
    String formattedDate = "";
    formattedDate = df.format(date);
    return formattedDate;
}

@Override
public int getNumberOfSections() {
    return sections.size();
}

@Override
public boolean doesSectionHaveHeader(int sectionIndex) {
    return true;
}

@Override
public boolean doesSectionHaveFooter(int sectionIndex) {
    return false;
}

@Override
public int getNumberOfItemsInSection(int sectionIndex) {
    return sections.get(sectionIndex).transactions.getTransactions().size();
}

@Override
public ItemViewHolder onCreateItemViewHolder(ViewGroup parent, int itemUserType) {
    LayoutInflater inflater = LayoutInflater.from(parent.getContext());
    View v = inflater.inflate(R.layout.wallet_item, parent, false);
    return new ItemViewHolder(v);
}

@Override
public HeaderViewHolder onCreateHeaderViewHolder(ViewGroup parent, int headerUserType) {
    LayoutInflater inflater = LayoutInflater.from(parent.getContext());
    View v = inflater.inflate(R.layout.wallet_header, parent, false);
    return new HeaderViewHolder(v);
}

@Override
public void onBindItemViewHolder(SectioningAdapter.ItemViewHolder viewHolder, int sectionIndex, int itemIndex, int itemType) {
    Section section = sections.get(sectionIndex);
    ItemViewHolder holder = (ItemViewHolder) viewHolder;
    Transaction transaction = section.transactions.getTransactions().get(itemIndex);
    holder.description.setText(transaction.getDescription());
    holder.ammount.setText(String.valueOf(transaction.getAmount()));
    holder.time.setText(parseDate(transaction.getCreatedDate()));
    holder.total.setText(String.valueOf(transaction.getNewCredits()));

}

@Override
public void onBindHeaderViewHolder(SectioningAdapter.HeaderViewHolder viewHolder, int sectionIndex, int headerType) {
    Section s = sections.get(sectionIndex);
    HeaderViewHolder hvh = (HeaderViewHolder) viewHolder;
    Transaction transaction = s.transactions.getTransactions().get(sectionIndex);
    if (USE_DEBUG_APPEARANCE) {
        hvh.itemView.setBackgroundColor(0x55ffffff);
        hvh.dateHeader.setText(pad(sectionIndex * 2) + s.alpha);
    } else {
        hvh.dateHeader.setText(parseDate(transaction.getCreatedDate()));
    }
}

private String pad(int spaces) {
    StringBuilder b = new StringBuilder();
    for (int i = 0; i < spaces; i++) {
        b.append(' ');
    }
    return b.toString();
}


public class HeaderViewHolder extends SectioningAdapter.HeaderViewHolder {

    TextView dateHeader;

    public HeaderViewHolder(View itemView) {
        super(itemView);
        dateHeader = (TextView) itemView.findViewById(R.id.date);
    }
}

public class ItemViewHolder extends SectioningAdapter.ItemViewHolder {

    TextView description;
    TextView time;
    TextView ammount;
    TextView total;

    public ItemViewHolder(View itemView) {
        super(itemView);
        description = (TextView) itemView.findViewById(R.id.description);
        time = (TextView) itemView.findViewById(R.id.time);
        ammount = (TextView) itemView.findViewById(R.id.ammount);
        total = (TextView) itemView.findViewById(R.id.new_credits);
    }
}

}

So if I do it this way, It sorts and creates headers/sections by date, but it puts all transactions in all sections, not inside matching date...

you can sort the arraylist on the basis of date before sending it to the adapter — M Monis Ahmed Khan, May 11 '17 at 11:46
It actually is sorted and i get it in headers, but the problem is, for each date I have to get only transactions on that date...if I had 2 transactions in a date, I would have 2 items below header, just like in the image I forgot to upload :) I'll edit my question so you can see — joe, May 11 '17 at 11:53

Nick Titov · Accepted Answer · 2017-05-11T14:45:55.797

Seems like this should handle if item should have header or no. Smth like, if it is first item with this date return true, if not - false.

@Override
public boolean doesSectionHaveHeader(int sectionIndex) {
    return true;
}

EDIT:

You can make filtered list before setting it. For example for address book with name letter header:

public class AddressBookDemoAdapter extends SectioningAdapter {

    Locale locale = Locale.getDefault();
    static final boolean USE_DEBUG_APPEARANCE = false;

    private class Section {
        String alpha;
        ArrayList<Person> people = new ArrayList<>();
    }

    public class ItemViewHolder extends SectioningAdapter.ItemViewHolder {
        TextView personNameTextView;

        public ItemViewHolder(View itemView) {
            super(itemView);
            personNameTextView = (TextView) itemView.findViewById(R.id.personNameTextView);
        }
    }

    public class HeaderViewHolder extends SectioningAdapter.HeaderViewHolder {
        TextView titleTextView;

        public HeaderViewHolder(View itemView) {
            super(itemView);
            titleTextView = (TextView) itemView.findViewById(R.id.titleTextView);
        }
    }


    List<Person> people;
    ArrayList<Section> sections = new ArrayList<>();

    public AddressBookDemoAdapter() {
    }

    public List<Person> getPeople() {
        return people;
    }

    public void setPeople(List<Person> people) {
        this.people = people;
        sections.clear();

        // sort people into buckets by the first letter of last name
        char alpha = 0;
        Section currentSection = null;
        for (Person person : people) {
            if (person.name.last.charAt(0) != alpha) {
                if (currentSection != null) {
                    sections.add(currentSection);
                }

                currentSection = new Section();
                alpha = person.name.last.charAt(0);
                currentSection.alpha = String.valueOf(alpha);
            }

            if (currentSection != null) {
                currentSection.people.add(person);
            }
        }

        sections.add(currentSection);
        notifyAllSectionsDataSetChanged();
    }

    @Override
    public int getNumberOfSections() {
        return sections.size();
    }

    @Override
    public int getNumberOfItemsInSection(int sectionIndex) {
        return sections.get(sectionIndex).people.size();
    }

    @Override
    public boolean doesSectionHaveHeader(int sectionIndex) {
        return true;
    }

    @Override
    public boolean doesSectionHaveFooter(int sectionIndex) {
        return false;
    }

    @Override
    public ItemViewHolder onCreateItemViewHolder(ViewGroup parent, int itemType) {
        LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        View v = inflater.inflate(R.layout.list_item_addressbook_person, parent, false);
        return new ItemViewHolder(v);
    }

    @Override
    public HeaderViewHolder onCreateHeaderViewHolder(ViewGroup parent, int headerType) {
        LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        View v = inflater.inflate(R.layout.list_item_addressbook_header, parent, false);
        return new HeaderViewHolder(v);
    }

    @SuppressLint("SetTextI18n")
    @Override
    public void onBindItemViewHolder(SectioningAdapter.ItemViewHolder viewHolder, int sectionIndex, int itemIndex, int itemType) {
        Section s = sections.get(sectionIndex);
        ItemViewHolder ivh = (ItemViewHolder) viewHolder;
        Person person = s.people.get(itemIndex);
        ivh.personNameTextView.setText(capitalize(person.name.last) + ", " + capitalize(person.name.first));
    }

    @SuppressLint("SetTextI18n")
    @Override
    public void onBindHeaderViewHolder(SectioningAdapter.HeaderViewHolder viewHolder, int sectionIndex, int headerType) {
        Section s = sections.get(sectionIndex);
        HeaderViewHolder hvh = (HeaderViewHolder) viewHolder;

        if (USE_DEBUG_APPEARANCE) {
            hvh.itemView.setBackgroundColor(0x55ffffff);
            hvh.titleTextView.setText(pad(sectionIndex * 2) + s.alpha);
        } else {
            hvh.titleTextView.setText(s.alpha);
        }
    }

    private String capitalize(String s) {
        if (s != null && s.length() > 0) {
            return s.substring(0,1).toUpperCase(locale) + s.substring(1);
        }

        return "";
    }

    private String pad(int spaces) {
        StringBuilder b = new StringBuilder();
        for (int i = 0; i < spaces; i++) {
            b.append(' ');
        }
        return b.toString();
    }

}

I'm not really sure how to write that.. I would appreciate if you can give me a hint... but I think this is the major issue, since I get all transactions for every date(section), but I don't know how should I write it : @Override public int getNumberOfItemsInSection(int sectionIndex) { return sections.get(sectionIndex).transactions.getTransactions().size(); } — joe, May 11 '17 at 12:39
I tried to solve the issue with headers by adding all transaction dates in TreeSet and then looping through them, but it's not helping (inside setTransactions() method .. — joe, May 11 '17 at 12:47
@joe how about smth like that? return sectionIndex == 0 ? true : item.get(sectionIndex).getDate() != item.get(sectionIndex-1).getDate(); — Nick Titov, May 11 '17 at 12:52
great! I just had to compare parsed dates since date won't be equal because of different tame... Do you have any idea how to handle getNumberOfItemsInSection() method? — joe, May 11 '17 at 13:11
@joe updated my answer. Added some examlpe with address book. — Nick Titov, May 11 '17 at 14:47
Yep, this is what I followed... I get this thing with 0th index... but how would I compare (make sections) based on dates parsed in string with this format: "dd.MM.yyyy" ? — joe, May 12 '17 at 07:05
@joe just compare dates, not first letters. What the problem? — Nick Titov, May 12 '17 at 07:13

score -1 · Answer 2 · answered May 11 '17 at 12:30

-1

You can use comparable interface in your Transaction class and compare with particular field you want to sort

answered May 11 '17 at 12:30

Sandeep dhiman

1,863
2
17
22

I think I don't have to since I get them sorted in response ASC or DESC... but the problem are those headers(sections) and the data(transactions) for each date(section) ... it lists all transactions for every date – joe May 11 '17 at 12:37

How to sort items in RecyclerView depending on a Date

2 Answers2