Я новичок в разработке приложений для Android. Я хочу отобразить имя пользователя из моей таблицы в базе данных SQLite после успешного входа в файл layout_main.xml с именем действия HomeActivity.Код для моего textview в моем макете activity_main.xml
<TextView
android:id="@+id/NamaProfile"
android:layout_width="120dp"
android:layout_height="20dp"
android:layout_marginStart="160dp"
android:layout_marginTop="30dp"
android:text="TextView" />
А вот код:
DBHelper
package com.demo.androidgudang;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
/**
* Created by Administrator on 5/5/2016.
*/
public class DbHelper extends SQLiteOpenHelper {
public static final String TAG = DbHelper.class.getSimpleName();
public static final String DB_NAME = "myapp.db";
public static final int DB_VERSION = 1;
public static final String USER_TABLE = "users";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_USERNAME = "username";
public static final String COLUMN_EMAIL = "email";
public static final String COLUMN_PASS = "password";
/*
create table users(
id integer primary key autoincrement,
email text,
password text);
*/
public static final String CREATE_TABLE_USERS = "CREATE TABLE " + USER_TABLE + "("
+ COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT,"
+ COLUMN_USERNAME + " TEXT,"
+ COLUMN_EMAIL + " TEXT,"
+ COLUMN_PASS + " TEXT);";
public DbHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_TABLE_USERS);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + USER_TABLE);
onCreate(db);
}
/**
* Storing user details in database
* */
public void addUser(String username,String email,String password) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(COLUMN_USERNAME, username);
values.put(COLUMN_EMAIL, email);
values.put(COLUMN_PASS, password);
long id = db.insert(USER_TABLE, null, values);
db.close();
Log.d(TAG, "user inserted" + id);
}
public boolean getUser(String username, String email, String pass){
//HashMap<String, String> user = new HashMap<String, String>();
String selectQuery = "select * from " + USER_TABLE + " where " +
COLUMN_USERNAME + " = " + "'"+username+"'" + " and " + COLUMN_PASS + " = " + "'"+pass+"'";
if(email != null)
selectQuery += "and " + COLUMN_EMAIL + " = " + "'"+email+"'";
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// Move to first row
cursor.moveToFirst();
if (cursor.getCount() > 0) {
return true;
}
cursor.close();
db.close();
return false;
}
}
HomeActivity
package com.demo.androidgudang;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class HomeActivity extends AppCompatActivity {
TextView txt_profile_name;
SharedPreferences sharedpreferences;
Intent intent;
private Button btnLogout;
private Session session;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
session = new Session(this);
if(!session.loggedin()){
logout();
}
btnLogout = (Button)findViewById(R.id.btnLogout);
btnLogout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
logout();
}
});
}
private void logout(){
session.setLoggedin(false);
finish();
startActivity(new Intent(HomeActivity.this,LoginActivity.class));
}
}
Session.java
package com.demo.androidgudang;
import android.content.Context;
import android.content.SharedPreferences;
/**
* Created by Administrator on 5/5/2016.
*/
public class Session {
SharedPreferences prefs;
SharedPreferences.Editor editor;
Context ctx;
public Session(Context ctx){
this.ctx = ctx;
prefs = ctx.getSharedPreferences("myapp", Context.MODE_PRIVATE);
editor = prefs.edit();
}
public void setLoggedin(boolean logggedin){
editor.putBoolean("loggedInmode",logggedin);
editor.commit();
}
public boolean loggedin(){
return prefs.getBoolean("loggedInmode", false);
}
}
LoginActivity.java
package com.demo.androidgudang;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class LoginActivity extends AppCompatActivity implements View.OnClickListener{
private Button login;
private EditText etUsername, etPass;
private DbHelper db;
private Session session;
TextView RegisterDisini;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
db = new DbHelper(this);
session = new Session(this);
login = (Button)findViewById(R.id.btnLogin);
etUsername = (EditText)findViewById(R.id.etUsername);
etPass = (EditText)findViewById(R.id.etPass);
login.setOnClickListener(this);
RegisterDisini = (TextView) findViewById(R.id.RegisterDisini);
RegisterDisini.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent registerHere = new Intent(LoginActivity.this, RegisterActivity.class);
startActivity(registerHere);
}
});
if(session.loggedin()){
startActivity(new Intent(LoginActivity.this,HomeActivity.class));
finish();
}
}
@Override
public void onClick(View v) {
switch(v.getId()){
case R.id.btnLogin:
login();
break;
default:
}
}
private void login(){
String username = etUsername.getText().toString();
String pass = etPass.getText().toString();
if(db.getUser(username,null,pass)){
session.setLoggedin(true);
startActivity(new Intent(LoginActivity.this, HomeActivity.class));
finish();
}else{
Toast.makeText(getApplicationContext(), "Wrong username/password",Toast.LENGTH_SHORT).show();
}
}
}