communication with sqlite (Create , insert, update,delete)

Step 1> Create a xml with name activity_main.xml



 <RelativeLayout xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

     <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="38dp"
        android:text="eid"
        android:textAppearance="?android:attr/textAppearanceMedium" />

        <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/textView1"
        android:layout_marginTop="44dp"
        android:text="ename"
        android:textAppearance="?android:attr/textAppearanceMedium" />

         <TextView
        android:id="@+id/textView3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/textView2"
        android:layout_marginTop="46dp"
        android:text="desig"
        android:textAppearance="?android:attr/textAppearanceMedium" />

         <TextView
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/textView1"
        android:layout_marginLeft="45dp"
        android:layout_toRightOf="@+id/textView1"
        android:ems="10" >

        
    

         <EditText
        android:id="@+id/editText2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/editText1"
        android:layout_alignTop="@+id/textView2"
        android:ems="10" />

             <EditText
        android:id="@+id/editText3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/textView3"
        android:layout_alignLeft="@+id/editText2"
        android:ems="10" />

                         <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/button3"
        android:layout_alignRight="@+id/editText3"
        android:layout_marginBottom="42dp"
        android:layout_marginRight="46dp"
        android:onClick="read"
        android:text="Read" />

                         <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/button2"
        android:layout_alignBottom="@+id/button2"
        android:layout_toRightOf="@+id/textView1"
        android:onClick="insert"
        android:text="Insert" />

             <Button
        android:id="@+id/button3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button1"
        android:layout_alignParentBottom="true"
        android:layout_marginBottom="42dp"
        android:onClick="update"
        android:text="Update" />

                 <Button
        android:id="@+id/button4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignRight="@+id/button2"
        android:layout_below="@+id/button2"
        android:onClick="delete"
        android:text="Delete" />

<RelativeLayout/>









Step 2> Paste it in MainActivity.java


import android.app.Activity;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

SQLiteDatabase db;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

db=openOrCreateDatabase("emp_db", Context.MODE_PRIVATE, null);


db.execSQL("create table if not exists emp_details (eid number,ename varchar(40),desig varchar(40))");


}


public void insert(View v){

EditText et1=(EditText)findViewById(R.id.editText1);
EditText et2=(EditText)findViewById(R.id.editText2);
EditText et3=(EditText)findViewById(R.id.editText3);

ContentValues cv=new ContentValues();

cv.put("eid",et1.getText().toString());
cv.put("ename",et2.getText().toString());
cv.put("desig", et3.getText().toString());

 db.insert("emp_details", null, cv);


}

public void read(View v){


EditText et1=(EditText)findViewById(R.id.editText1);

Cursor c=db.query("emp_details", new String[]{"eid","ename","desig"}, "eid=?", new String[]{et1.getText().toString()},null, null, null);


while(c.moveToNext()){



Toast.makeText(getApplicationContext(), "Eid is :"+c.getInt(0)+"\n "+"Ename is :"+c.getString(1)+"Desig is :"+c.getString(2),2000).show();

}


}

public void update(View v){

EditText et1=(EditText)findViewById(R.id.editText1);
EditText et2=(EditText)findViewById(R.id.editText2);
EditText et3=(EditText)findViewById(R.id.editText3);

ContentValues cv=new ContentValues();

cv.put("ename",et2.getText().toString());
cv.put("desig", et3.getText().toString());

db.update("emp_details",cv, "eid=?",new String[]{et1.getText().toString()});


}

public void delete(View v){

EditText et1=(EditText)findViewById(R.id.editText1);

db.delete("emp_details","eid=?",new String[]{et1.getText().toString()}); 


// db.execSQL("delete from emp_details where eid="+et1.getText().toString());


}


}