Dear friends we will see how to create a sample project demo using SQLite.
steps to create a demo on sqlite.
1. copy below code of DatabaseHelper.java class.
/**
*
*/
package com.android.sqlite.db;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
/**
* @author Sandeep
* @since 18 Nov 2011
*/
public class DatabaseHelper extends SQLiteOpenHelper {
private static final String DB_PATH = "/data/data/com.android.sqlite/databases/";
private static final String DB_NAME = "example.db";
/**
* @param context
* @param name
* @param factory
* @param version
*/
public DatabaseHelper(Context context, String name, CursorFactory factory,
int version) {
super(context, name, factory, version);
}
@Override
public void onCreate(SQLiteDatabase db) {
// TBL_CONTACT
String query = "CREATE TABLE CONTACT "+" "+" (ID INTEGER, FName TEXT, LName TEXT, Contact_no TEXT);";
db.execSQL(query);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
/**
* Check if the database already exist to avoid
* re-copying the file each time you open the application.
* @return true if it exists, false if it doesn't
*/
public boolean checkDataBase(){
SQLiteDatabase checkDB = null;
try{
String myPath = DB_PATH + DB_NAME;
checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
}catch(SQLiteException e){
//database does't exist yet.
}
if(checkDB != null){
checkDB.close();
}
return checkDB != null ? true : false;
}
}
2. Now create a class DBOperation.java which contain all insert,delete functions.
package com.android.sqlite.db;
import com.android.sqlite.newcontact;
import com.android.sqlite.welcome;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
public class DbOperation {
DatabaseHelper dbHelper = null;
public DbOperation() {
dbHelper = welcome.dbHelper;
}
/* Add contact */
public void addContact(String fname, String lname, String number) {
SQLiteDatabase db = dbHelper.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put("FName", fname);
cv.put("LName", lname);
cv.put("Contact_no", number);
db.insert("CONTACT", null, cv);
db.close();
}
public String[][] getAll(String query){
String[][] array = null;
SQLiteDatabase db = null;
Cursor cursor = null;
try {
db = dbHelper.getReadableDatabase();
cursor = db.rawQuery(query, null);
if(!cursor.isFirst()){
cursor.moveToFirst();
}
int rowCount = cursor.getCount();
int columnCount = cursor.getColumnCount();
array = new String[rowCount][columnCount];
int index =0;
if(cursor.isFirst()){
do{
for(int j=0;j<columnCount;j++){
array[index][j]= cursor.getString(j);
System.out.println(cursor.getColumnName(j)+":"+cursor.getString(j));
System.out.println();
}
index++;
}while(cursor.moveToNext());
}
} catch (Exception e) {
e.printStackTrace();
}finally{
if(cursor!=null)
cursor.close();
if(db!=null)
db.close();
}
return array;
}
}
3. Now copy these code in main.java
package com.android.sqlite;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.android.sqlite.db.DatabaseHelper;
import com.android.sqlite.db.DbOperation;
/**
*
* @author Sandeep Sharma
*
*/
public class welcome extends Activity {
public static DatabaseHelper dbHelper=null;
public DbOperation dboper=null;
private boolean dbExist;
private EditText fname,lname,contact;
Button newcontact;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.lead_list);
//---create db ---
dbHelper = new DatabaseHelper(this,"example.db",
null,1);
dbExist = dbHelper.checkDataBase();
dboper=new DbOperation();
fname=(EditText)findViewById(R.id.edt_Fname);
lname=(EditText)findViewById(R.id.edt_Lname);
contact=(EditText)findViewById(R.id.edt_contact);
newcontact=(Button)findViewById(R.id.button1);
newcontact.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
dboper.addContact(fname.getText().toString() , lname.getText().toString(), contact.getText().toString());
Toast.makeText(getApplicationContext(), "Record Saved!", Toast.LENGTH_SHORT).show();
}
});
}
}
4. Overwrite your main.xml with below code.
<?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="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/lbl_Fname"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/FName"
android:textAppearance="?android:attr/textAppearanceLarge" />
<EditText
android:id="@+id/edt_Fname"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="textPersonName" >
<requestFocus />
</EditText>
<TextView
android:id="@+id/lbl_Lname"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/LName"
android:textAppearance="?android:attr/textAppearanceLarge" />
<EditText
android:id="@+id/edt_Lname"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="textPersonName" >
<requestFocus />
</EditText>
<TextView
android:id="@+id/lbl_contact"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/Contact"
android:textAppearance="?android:attr/textAppearanceLarge" />
<EditText
android:id="@+id/edt_contact"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="textPersonName" >
<requestFocus />
</EditText>
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Save" android:gravity="center_vertical|center_horizontal" android:layout_gravity="center_horizontal" android:layout_margin="30dip"/>
</LinearLayout>
Now try to run code. If any variable declaration missing please correct it.
Now once you get these demo working you can find sqlite database file.
to get sqlite database file switch to ddms perspective. open file explorer you can see your database file in path below.
data/data/your_packagename/databases/example.db
to open this file you need sqlite browser.
click here to download sqlite browser
