how to insert data sqlite using kotlin android

how to insert  data  SQLite using kotlin  android 

Today learn how to insert data  SQLite using kotlin  android follow the  SQLite using kotlin android. for follow the site: google android developer

SQLite is an open-source relational database that is used to perform database operations on Android devices such as storing, manipulating or retrieving persistent data from the database.

By default SQLite database is embedded in android. So, there is no need to perform any database setup or administration task.

The SQLiteOpenHelper class provides the functionality to use the SQLite database.

1.MainActivity.kt:

import android.content.ContentValues

import android.content.Intent

import android.database.sqlite.SQLiteDatabase

import android.os.Bundle

import android.support.v7.app.ActionBarActivity

import android.view.Menu

import android.view.MenuItem

import android.view.View

import android.widget.Button

import android.widget.EditText

import android.widget.TextView

import android.widget.Toast

class MainActivity:ActionBarActivity() {

  internal var controller = DBController(this)

  internal var add:Button

  internal var view:Button

  internal var update:Button

  internal var delete:Button

  internal var placeid:EditText

  internal var place:EditText

  internal var country:EditText

  internal var infotext:TextView

  protected fun onCreate(savedInstanceState:Bundle) {

    super.onCreate(savedInstanceState)

    setContentView(R.layout.activity_main)

    placeid = findViewById(R.id.edplaceid) as EditText

    place = findViewById(R.id.edplace) as EditText

    country = findViewById(R.id.edcountry) as EditText

    add = findViewById(R.id.btnadd) as Button

    update = findViewById(R.id.btnupdate) as Button

    delete = findViewById(R.id.btndelete) as Button

    view = findViewById(R.id.btnview) as Button

    infotext = findViewById(R.id.txtresulttext) as TextView

    view.setOnClickListener(object:View.OnClickListener() {

      fun onClick(v:View) {

        val i = Intent(this@MainActivity, PlacesList::class.java)

        startActivity(i)

      }

    })

    add.setOnClickListener(object:View.OnClickListener() {

      fun onClick(v:View) {

        try

        {

          if (place.getText().toString().trim().equals("") || country.getText().toString().trim().equals(""))

          {

            infotext.setText("Please insert place name and country..")

          }

          else

          {

            controller = DBController(getApplicationContext())

            val db = controller.getWritableDatabase()

            val cv = ContentValues()

            cv.put("place", place.getText().toString())

            cv.put("country", country.getText().toString())

            db.insert("places", null, cv)

            db.close()

            infotext.setText("Place added Successfully")

          }

        }

        catch (ex:Exception) {

          infotext.setText(ex.message.toString())

        }

      }

    })

    update.setOnClickListener(object:View.OnClickListener() {

      fun onClick(v:View) {

        try

        {

          if ((place.getText().toString().trim().equals("") && country.getText().toString().trim().equals("")) || placeid.getText().toString().trim().equals(""))

          {

            infotext.setText("Please insert values to update..")

          }

          else

          {

            controller = DBController(getApplicationContext())

            val db = controller.getWritableDatabase()

            val cv = ContentValues()

            cv.put("place", place.getText().toString())

            cv.put("country", country.getText().toString())

            db.update("places", cv, "id=" + placeid.getText().toString(), null)

            Toast.makeText(this@MainActivity,

                           "Updated successfully", Toast.LENGTH_SHORT)

            .show()

            infotext.setText("Updated Successfully")

          }

        }

        catch (ex:Exception) {

          infotext.setText(ex.message.toString())

        }

      }

    })

    delete.setOnClickListener(object:View.OnClickListener() {

      fun onClick(v:View) {

        try

        {

          if (placeid.getText().toString().trim().equals(""))

          {

            infotext.setText("Please insert place ID to delete..")

          }

          else

          {

            controller = DBController(getApplicationContext())

            val db = controller.getWritableDatabase()

            db.delete("places", "id=" + placeid.getText().toString(), null)

            Toast.makeText(this@MainActivity,

                           "deleted successfully", Toast.LENGTH_SHORT)

            .show()

            infotext.setText("Deleted Successfully")

          }

        }

        catch (ex:Exception) {

          infotext.setText(ex.message.toString())

        }

      }

    })

  }

  fun onCreateOptionsMenu(menu:Menu):Boolean {

    // getMenuInflater().inflate(R.menu.menu_main, menu);

    return true

  }

  fun onOptionsItemSelected(item:MenuItem):Boolean {

    val id = item.getItemId()

    //if (id == R.id.action_settings) {

    return true

  }

  //return super.onOptionsItemSelected(item);

}

2. DBController.kt:

import android.content.Context

import android.database.Cursor

import android.database.sqlite.SQLiteDatabase

import android.database.sqlite.SQLiteOpenHelper

import java.util.ArrayList

import java.util.HashMap

class DBController(context:Context):SQLiteOpenHelper(context, databasename, null, versioncode) {

  // return contact list

  val allPlace:ArrayList<HashMap<String, String>>

  get() {

    val wordList:ArrayList<HashMap<String, String>>

    wordList = ArrayList<HashMap<String, String>>()

    val selectQuery = "SELECT * FROM " + tablename

    val database = this.getWritableDatabase()

    val cursor = database.rawQuery(selectQuery, null)

    if (cursor.moveToFirst())

    {

      do

      {

        val map = HashMap<String, String>()

        map.put("id", cursor.getString(0))

        map.put("place", cursor.getString(1))

        map.put("country", cursor.getString(2))

        wordList.add(map)

      }

      while (cursor.moveToNext())

    }

    return wordList

  }

  fun onCreate(database:SQLiteDatabase) {

    val query:String

    query = "CREATE TABLE IF NOT EXISTS " + tablename + "(" + id + " integer primary key, " + place + " text, " + country + " text)"

    database.execSQL(query)

  }

  fun onUpgrade(database:SQLiteDatabase, version_old:Int,

                current_version:Int) {

    val query:String

    query = "DROP TABLE IF EXISTS " + tablename

    database.execSQL(query)

    onCreate(database)

  }

  companion object {

    private val tablename = "places" // tablename

    private val place = "place" // column name

    private val id = "ID" // auto generated ID column

    private val country = "country" // column name

    private val databasename = "placesinfo" // Dtabasename

    private val versioncode = 1 //versioncode of the database

  }

}

3. PlacesList.kt:

 

import android.os.Bundle

import android.support.v7.app.ActionBarActivity

import android.view.Menu

import android.view.MenuItem

import android.widget.ListView

import android.widget.SimpleAdapter

import android.widget.TextView

import java.util.HashMap

class PlacesList:ActionBarActivity() {

  internal var controller = DBController(this)

  internal var ls:ListView

  internal var infotext:TextView

  protected fun onCreate(savedInstanceState:Bundle) {

    super.onCreate(savedInstanceState)

    setContentView(R.layout.placeslist)

    ls = findViewById(R.id.placeslist) as ListView

    infotext = findViewById(R.id.txtresulttext) as TextView

    try

    {

      val data = controller.getAllPlace()

      if (data.size != 0)

      {

        // Srno, RMCode, Fileno, Loc, FileDesc, TAGNos

        val adapter = SimpleAdapter(

          this@PlacesList, data, R.layout.rows,

          arrayOf<String>("id", "place", "country"), intArrayOf(R.id.txtplaceid, R.id.txtplacename, R.id.txtcountry))

        ls.setAdapter(adapter)

        val length = (data.size).toString()

        infotext.setText(length + " places")

      }

      else

      {

        infotext.setText("No data in database")

      }

    }

    catch (ex:Exception) {

      infotext.setText(ex.message.toString())

    }

  }

  fun onCreateOptionsMenu(menu:Menu):Boolean {

    // getMenuInflater().inflate(R.menu.menu_main, menu);

    return true

  }

  fun onOptionsItemSelected(item:MenuItem):Boolean {

    val id = item.getItemId()

    //if (id == R.id.action_settings) {

    return true

  }

  // return super.onOptionsItemSelected(item);

}

 

 

 

4. activity_main.xml:

 

<?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="vertical"

    android:weightSum="7"

    android:background="#ffb6ffb0">

 

    <TextView

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_weight="0.5"

        android:layout_margin="5dp"

        android:gravity="center_horizontal"

        android:text="PLACES TO VISIT : "

        android:textSize="25sp"

        android:textStyle="italic|normal" />

 

    <EditText

        android:id="@+id/edplaceid"

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_weight="1"

        android:layout_margin="5dp"

        android:hint="PLACE ID" />

 

    <EditText

        android:id="@+id/edplace"

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_weight="1"

        android:layout_margin="5dp"

        android:hint="PLACE NAME" />

 

    <EditText

        android:id="@+id/edcountry"

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_weight="1"

        android:layout_margin="5dp"

        android:hint="COUNTRY" />

 

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_weight="0.8"

        android:orientation="horizontal"

        android:weightSum="3">

 

        <Button

            android:id="@+id/btnadd"

            android:layout_width="0dp"

            android:layout_marginLeft="5dp"

            android:layout_marginRight="5dp"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:background="#ffff2f5d"

            android:textColor="#fff"

            android:textSize="20sp"

            android:text="ADD" />

 

        <Button

            android:id="@+id/btnupdate"

            android:layout_width="0dp"

            android:layout_marginLeft="5dp"

            android:layout_marginRight="5dp"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:background="#ffff2f5d"

            android:textColor="#fff"

            android:textSize="20sp"

            android:text="UPDATE" />

 

        <Button

            android:id="@+id/btndelete"

            android:layout_width="0dp"

            android:layout_marginLeft="5dp"

            android:layout_marginRight="5dp"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:background="#ffff2f5d"

            android:textColor="#fff"

            android:textSize="20sp"

            android:text="DELETE" />

    </LinearLayout>

 

    <Button

        android:id="@+id/btnview"

        android:layout_width="match_parent"

        android:layout_marginLeft="5dp"

        android:layout_marginRight="5dp"

        android:layout_marginTop="5dp"

        android:layout_height="0dp"

        android:layout_weight="0.8"

        android:background="#ff2b84ff"

        android:textColor="#fff"

        android:textSize="20sp"

        android:text="VIEW PLACES" />

 

    <TextView

        android:id="@+id/txtresulttext"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_marginLeft="5dp"

        android:layout_marginTop="15dp"

        android:gravity="left"

        android:text=""

        android:layout_weight="1"

        android:textStyle="italic|bold"

        android:textSize="20sp" />

</LinearLayout>

 

 

 5. placeslist.xml:

<?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="vertical"

    android:weightSum="10">

    <ListView

        android:id="@+id/placeslist"

        android:layout_width="match_parent"

        android:layout_weight="9"

        android:layout_height="0dp"

        android:layout_alignParentLeft="true"></ListView>

    <TextView

        android:id="@+id/txtresulttext"

        android:layout_width="match_parent"

        android:layout_height="0dp"

        android:layout_marginLeft="5dp"

        android:layout_marginTop="5dp"

        android:gravity="left"

        android:text=""

        android:layout_weight="1"

        android:textStyle="italic|bold"

        android:textSize="13sp" />

</LinearLayout>

 6. rows.xml :

 

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

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

    android:layout_width="fill_parent"

    android:layout_height="wrap_content"

    android:orientation="vertical" >

 

    <LinearLayout

        android:id="@+id/lvh"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:orientation="horizontal"

        android:scrollbars="horizontal"

        android:weightSum="4" >

 

        <TextView

            android:id="@+id/txtplaceid"

            android:layout_width="0dp"

            android:layout_height="wrap_content"

            android:layout_weight="0.6"

            android:gravity="center"

            android:text="1"

            android:background="#ffb6ffb0"

            android:textColor="#000"

            android:textSize="20sp" />

 

        <TextView

            android:id="@+id/txtplacename"

            android:layout_width="0dp"

            android:layout_height="wrap_content"

            android:layout_weight="1.7"

            android:gravity="center"

            android:text="Barcelona"

            android:background="#ffc5ffe3"

            android:textColor="#000"

            android:textSize="20sp" />

 

        <TextView

            android:id="@+id/txtcountry"

            android:layout_width="0dp"

            android:layout_height="wrap_content"

            android:layout_weight="1.7"

            android:gravity="center"

            android:text="Spain"

            android:background="#ffd3f5ff"

            android:textColor="#000"

            android:textSize="20sp" />

 

 

    </LinearLayout>

 

</LinearLayout>

 

 

 7. AndroidManifest.xml :

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

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

    package="com.prakash.shree.studentinformation">

 

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:roundIcon="@mipmap/ic_launcher_round"

        android:supportsRtl="true"

        android:theme="@style/AppTheme">

        <activity android:name=".MainActivity">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

 

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

 

</manifest>