java - passing data from sqlite to a texview -

i trying pass data sqlite table username textview in home fragment class, having difficulties displaying data in textview. here databasehelper class table created:

public class databasehandler extends sqliteopenhelper {

// static variables // database version private static final int database_version = 1;  // database name private static final string database_name = "u168512214_barzd";  // login table name private static final string table_login = "login";  // login table columns names private static final string key_id = "id"; private static final string key_name = "name"; private static final string key_email = "email"; private static final string key_uid = "uid"; private static final string key_created_at = "created_at";  public databasehandler(context context) {     super(context, database_name, null, database_version); }  // creating tables @override public void oncreate(sqlitedatabase db) {     string create_login_table = "create table " + table_login + "("             + key_id + " integer primary key,"             + key_name + " text,"             + key_email + " text unique,"             + key_uid + " text,"             + key_created_at + " text" + ")";     db.execsql(create_login_table); }  // upgrading database @override public void onupgrade(sqlitedatabase db, int oldversion, int newversion) {     // drop older table if existed     db.execsql("drop table if exists " + table_login);      // create tables again     oncreate(db); }  /**  * storing user details in database  * */ public void adduser(string name, string email, string uid, string created_at) {     sqlitedatabase db = this.getwritabledatabase();      contentvalues values = new contentvalues();     values.put(key_name, name); // name     values.put(key_email, email); // email     values.put(key_uid, uid); // email     values.put(key_created_at, created_at); // created @      // inserting row     db.insert(table_login, null, values);     db.close(); // closing database connection }  /**  * getting user data database  * */ public hashmap<string, string> getuserdetails(){     hashmap<string,string> user = new hashmap<string,string>();     string selectquery = "select  * " + table_login;      sqlitedatabase db = this.getreadabledatabase();     cursor cursor = db.rawquery(selectquery, null);     // move first row     cursor.movetofirst();     if(cursor.getcount() > 0){         log.i("key_name","value is: " + cursor.getstring(1));           log.i("key_email","value is: " + cursor.getstring(2));          log.i("key_uid","value is: " + cursor.getstring(3));          log.i("key_created_at","value is: " + cursor.getstring(4));     }     cursor.close();     db.close();     // return user     return user; }   /**  * getting user login status  * return true if rows there in table  * */ public int getrowcount() {     string countquery = "select  * " + table_login;     sqlitedatabase db = this.getreadabledatabase();     cursor cursor = db.rawquery(countquery, null);     int rowcount = cursor.getcount();     db.close();     cursor.close();      // return row count     return rowcount; } 

her fragmenthome class want display username in textview:

databasehandler db;

alertdialogmanager alert = new alertdialogmanager(); 

// session manager class arraylist> namelist;

public homefragment(){}  @override public view oncreateview(layoutinflater inflater, viewgroup container,         bundle savedinstancestate) {      view rootview = inflater.inflate(r.layout.fragment_home, container, false);                    btnviewbars = (button)rootview.findviewbyid(r.id.btnviewbars);           btnnewbar = (button)rootview.findviewbyid(r.id.btncreatebar);     // return rootview;           db= new databasehandler(getactivity());             hashmap<string, string> user = db.getuserdetails();            for(int i=0; i<user.size();i++) {          username.settext(user.get(i).get("name"));             }