Android development Хичээл #3

Энэ удаагийн андройдийн хичээл бид нар ORMLite Database болон Custom Adapterийн анх жишээг үзсэн билээ.
Жишээгээр Оюутны нэр код харуулдаг app хийсэн билээ.


1.Анх Project-ээ үүсгэсний дараа ORMLite-ийн  2 library-ийг /libs гэсэн folder рүү хуулна.

2.Өөрийнхөө package дээрээ DatabaseHelper болон Student гэсэн модел классаа үүсгэнэ.
Student.class

package mn.csms.databasetest;

import com.j256.ormlite.field.DatabaseField;
import com.j256.ormlite.table.DatabaseTable;

@DatabaseTable
public class Student {
@DatabaseField(generatedId=true)
public int id;
@DatabaseField(unique=true,canBeNull=false)
public String code;
@DatabaseField
public String name;
}

DatabaseHelper.class

package mn.csms.databasetest;

import java.sql.SQLException;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;

import com.j256.ormlite.android.apptools.OrmLiteSqliteOpenHelper;
import com.j256.ormlite.dao.Dao;
import com.j256.ormlite.support.ConnectionSource;
import com.j256.ormlite.table.TableUtils;

public class DatabaseHelper extends OrmLiteSqliteOpenHelper {
 public static String databaseName = "student.db";
 public static int databaseVersion = 1;
 Dao<Student, Integer> studentDao = null;

 public DatabaseHelper(Context context) {
  super(context, databaseName, null, databaseVersion);
  // TODO Auto-generated constructor stub
 }

 @Override
 public void onCreate(SQLiteDatabase arg0, ConnectionSource arg1) {
  // TODO Auto-generated method stub
  try {
   TableUtils.createTableIfNotExists(connectionSource, Student.class);
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }

 @Override
 public void onUpgrade(SQLiteDatabase database, ConnectionSource arg1,
   int arg2, int arg3) {
  // TODO Auto-generated method stub
  try {
   TableUtils.createTable(connectionSource, Student.class);
//   onCreate(database);
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }

 public Dao<Student, Integer> getStudentDao() throws SQLException {
  if (studentDao == null){
   studentDao = getDao(Student.class);}
  return studentDao;
 }

 @Override
 public void close() {
  // TODO Auto-generated method stub
  super.close();
  studentDao = null;
 }

}

Дараа нь activity_main.xml class дээрээ ListView view нэмнэ энгэснээр listview дээ бид нар custom adapter тавина.

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context=".MainActivity" >



    <ListView

        android:id="@+id/studentList"

        android:layout_width="match_parent"

        android:layout_height="wrap_content" >

    </ListView>



</RelativeLayout>

Тэгээд adapter дээрээ ашиглах шинэ student_list_item.xml гэсэн xml layout үүсгэнэ.

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="horizontal"

    android:padding="5dp" >




    <TextView

        android:id="@+id/studentName"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_weight="1"

        android:textColor="@android:color/black"

        android:textAppearance="?android:attr/textAppearanceSmall" />




    <TextView

        android:id="@+id/studentCode"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_weight="1"

        android:textAppearance="?android:attr/textAppearanceSmall" />




    <Button

        android:id="@+id/delete"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_margin="5dp"

        android:layout_weight="1"

        android:text="Delete" />




</LinearLayout>

Үүний дараа MainActivity.class

package mn.csms.databasetest;

import java.sql.SQLException;
import java.util.List;

import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {
 private DatabaseHelper helper;
 private String[] studentName = { "Jargal", "Uguumur", "Alge", "Tseegii" };
 private String[] studentCode = { "D.SW10D00" };
 private List<Student> students;
 private ListView lv;
 private StudentAdapter adapter;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  lv = (ListView) findViewById(R.id.studentList);
  helper = new DatabaseHelper(this);
  try {
   students = helper.getStudentDao().queryForAll();
  } catch (SQLException e1) {
   // TODO Auto-generated catch block
   e1.printStackTrace();
  }
  //herev database hooson bol shine ugugluudee nemne
  if (students.size()==0) {
   for (int i = 0; i < studentName.length; i++) {
    Student student = new Student();
    student.name = studentName[i];
    student.code = studentCode[0] + i;
    Log.i("student", student.code);
    try {
     //helper class iig ashiglaj nemj bna 
     helper.getStudentDao().create(student);
    } catch (SQLException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
    }
   }
  }
  try {
   //Database iin buh ugudliig List<Student> turultei avch bna 
   students = helper.getStudentDao().queryForAll();
  } catch (SQLException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  Log.i("size", students.size()+"");
  //custom adapter buyu student-d zoriulsan adapter classiig duudaj bna 
  adapter=new StudentAdapter(getApplicationContext(),0, 0, students);
  lv.setAdapter(adapter);
 }
//Custom adapter class
 private class StudentAdapter extends ArrayAdapter<Student> {

  public StudentAdapter(Context context, int resource,int text,
    List<Student> objects) {
   super(context, resource, text,objects);
  }

  @Override
  public View getView(int position, View view, ViewGroup parent) {
   // TODO Auto-generated method stub
   Holder holder = null;
   final Student student = getItem(position);
   if (view == null) {
    //R.layout.student_list_item layoutiig inflate hiij oruulj irj bna 
    LayoutInflater inflater = getLayoutInflater();
    view = inflater.inflate(R.layout.student_list_item, null);
    holder = new Holder();
    holder.name = (TextView) view.findViewById(R.id.studentName);
    holder.code = (TextView) view.findViewById(R.id.studentCode);
    holder.delete = (Button) view.findViewById(R.id.delete);
    view.setTag(holder);
   } else {
    holder = (Holder) view.getTag();
   }
   holder.name.setText(student.name);
   holder.code.setText(student.code);
   holder.delete.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {
     // TODO Auto-generated method stub
     //delete buttong darahad 
     
      adapter.remove(student);
      Toast.makeText(getApplicationContext(), student.name+" ugugdul amjilttai ustlaa", Toast.LENGTH_SHORT);

    
     
    }
   });
   return view;
  }
 }
 //studented zoriulsan viewiig class turultei zarlaj uguh heregtei
 class Holder {
  TextView name;
  TextView code;
  Button delete;
 }

 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
  // Inflate the menu; this adds items to the action bar if it is present.
  getMenuInflater().inflate(R.menu.main, menu);
  return true;
 }

}

Screenshot:

Заз тэгээд миний хичээл дууслаа source кодийг нь энэ линкээр татаж аваарай :)