如何使用 ListView 删除 Android Studio 显示中的重复联系人 [重复]

Question

我正在编写一个程序来在 hp 中显示我的联系人列表，但我总是得到重复的联系人。我的代码哪里不对？

display my code run

这是我的代码

在这里我很困惑如何制作不需要将重复联系人添加到列表视图的过滤器：

contactModelArrayList = new ArrayList<>();
String[] projection = new String[]{
        ContactsContract.CommonDataKinds.Phone.NUMBER,
        ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME
};
Cursor phones = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,
        projection,
        ContactsContract.Contacts.IN_VISIBLE_GROUP + " = '1'",
        null,
        ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME+" COLLATE LOCALIZED ASC");

while (phones.moveToNext())
{
    String name=phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
    String phoneNumber = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));

    ContactModel contactModel = new ContactModel();
    contactModel.setName(name);
    contactModel.setNumber(phoneNumber);

    contactModelArrayList.add(contactModel);

}

phones.close();

contactAllAdapter = new ContactAllAdapter(this,contactModelArrayList);
listView.setAdapter(contactAllAdapter);

这用于文件 ContactAll 适配器

public class ContactAllAdapter extends BaseAdapter {
    private Context context;
    private ArrayList<ContactModel> contactModels;
    private String kode, nomor;

    public ContactAllAdapter(Context context, ArrayList<ContactModel> contactModels) {
        this.context = context;
        this.contactModels = contactModels;
    }

    @Override
    public int getViewTypeCount() {
        if(getCount() > 0){
            return getCount();
        }else{
            return super.getViewTypeCount();
        }
    }

    @Override
    public int getCount() {
        return contactModels.size();
    }

    @Override
    public Object getItem(int position) {
        return contactModels.get(position);
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {
        final ViewHolder holder;

        if (convertView == null) {
            holder = new ViewHolder();
            LayoutInflater inflater = (LayoutInflater) context
                    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.row_all_contact, null, true);

            holder.cname = convertView.findViewById(R.id.contact_name);
            holder.cnumber = convertView.findViewById(R.id.contact_number);
            holder.cinvite = convertView.findViewById(R.id.contact_invite);

            convertView.setTag(holder);
        }else {
            // the getTag returns the viewHolder object set as a tag to the view
            holder = (ViewHolder)convertView.getTag();
        }

        holder.cname.setText(contactModels.get(position).getName());
        holder.cnumber.setText(contactModels.get(position).getNumber());

        holder.cinvite.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                final String appPackageName = context.getPackageName();
                String text = context.getResources().getString(R.string.share_app_text);
                String link = "https://play.google.com/store/apps/details?id=" + appPackageName;//app link is auto generated by using package name

                Intent sendIntent = new Intent(Intent.ACTION_VIEW);
                sendIntent.putExtra("sms_body", text+"\n\n"+link);
                sendIntent.putExtra("address", contactModels.get(position).getNumber());
                sendIntent.setType("vnd.android-dir/mms-sms");
                context.startActivity(sendIntent);
            }
        });

        return convertView;
    }

    private class ViewHolder {

        protected TextView cname, cnumber;
        protected Button cinvite;
    }
}

还有Contact Model这个文件类

public class ContactModel {

    private String name, number;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getNumber() {
        return number;
    }

    public void setNumber(String number) {
        this.number = number;
    }
}

Answer 1

在您的活动中（第一段代码）：

    Set<ContactModel> contactModelSet = new HashSet<>();

    // the same ...

    ArrayList<ContactModel> contactModelArrayList = new ArrayList<>(contactModelSet);

    contactAllAdapter = new ContactAllAdapter(this,contactModelArrayList);

在 ContactModel 类中：

@Override
public int hashCode() {
    // calculate hash code if needed, something like this
    return this.name.hashCode() + this.number.hashCode();
}

@Override
public boolean equals(Object obj) {
    if (obj instanceof ContactModel) {
        ContactModel cm = (ContactModel) obj;
        return this.getName().equals(cm.getName()) && this.getNumber().equals(cm.getNumber());
    }
    return false;
}

@Override
public int compareTo(ContactModel o) {
    // implement if you need to order
    // don't know your criteria
    // must return -1, 0, 1 if this is less, equal or greater than o
    return 0;
}