Edit row in SQLite database using SQLiteDatabase.update().

Edit row in SQLite database using SQLiteDatabase.update().

update() of SQLiteDatabase class provide convenience method for updating rows in the database.



Further work on last exercise "Delete row in SQLite database".

Modify SQLiteAdapter.java to implement update_byID() method.

package com.exercise.AndroidSQLite;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;

public class SQLiteAdapter {

 public static final String MYDATABASE_NAME = "MY_DATABASE";
 public static final String MYDATABASE_TABLE = "MY_TABLE";
 public static final int MYDATABASE_VERSION = 1;
 public static final String KEY_ID = "_id";
 public static final String KEY_CONTENT1 = "Content1";
 public static final String KEY_CONTENT2 = "Content2";

 //create table MY_DATABASE (ID integer primary key, Content text not null);
 private static final String SCRIPT_CREATE_DATABASE =
  "create table " + MYDATABASE_TABLE + " ("
  + KEY_ID + " integer primary key autoincrement, "
  + KEY_CONTENT1 + " text not null, "
  + KEY_CONTENT2 + " text not null);";
 
 private SQLiteHelper sqLiteHelper;
 private SQLiteDatabase sqLiteDatabase;

 private Context context;
 
 public SQLiteAdapter(Context c){
  context = c;
 }
 
 public SQLiteAdapter openToRead() throws android.database.SQLException {
  sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
  sqLiteDatabase = sqLiteHelper.getReadableDatabase();
  return this; 
 }
 
 public SQLiteAdapter openToWrite() throws android.database.SQLException {
  sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
  sqLiteDatabase = sqLiteHelper.getWritableDatabase();
  return this; 
 }
 
 public void close(){
  sqLiteHelper.close();
 }
 
 public long insert(String content1, String content2){
  
  ContentValues contentValues = new ContentValues();
  contentValues.put(KEY_CONTENT1, content1);
  contentValues.put(KEY_CONTENT2, content2);
  return sqLiteDatabase.insert(MYDATABASE_TABLE, null, contentValues);
 }
 
 public int deleteAll(){
  return sqLiteDatabase.delete(MYDATABASE_TABLE, null, null);
 }
 
 public void delete_byID(int id){
  sqLiteDatabase.delete(MYDATABASE_TABLE, KEY_ID+"="+id, null);
 }
 
 public void update_byID(int id, String v1, String v2){
  ContentValues values = new ContentValues();
  values.put(KEY_CONTENT1, v1);
  values.put(KEY_CONTENT2, v2);
  sqLiteDatabase.update(MYDATABASE_TABLE, values, KEY_ID+"="+id, null);
 }
 
 public Cursor queueAll(){
  String[] columns = new String[]{KEY_ID, KEY_CONTENT1, KEY_CONTENT2};
  Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE, columns,
    null, null, null, null, null);
  
  return cursor;
 }
 
 public class SQLiteHelper extends SQLiteOpenHelper {

  public SQLiteHelper(Context context, String name,
    CursorFactory factory, int version) {
   super(context, name, factory, version);
  }

  @Override
  public void onCreate(SQLiteDatabase db) {
   // TODO Auto-generated method stub
   db.execSQL(SCRIPT_CREATE_DATABASE);
  }

  @Override
  public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
   // TODO Auto-generated method stub

  }

 }
 
}

Update AndroidSQLite.java, modify listContentOnItemClickListener to change the dialogC1_id and dialogC1_id to final EditText, and also add button to update SQLite database withmySQLiteAdapter.update_byID().

package com.exercise.AndroidSQLite;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;

public class AndroidSQLite extends Activity {
 
 EditText inputContent1, inputContent2;
 Button buttonAdd, buttonDeleteAll;
 
 private SQLiteAdapter mySQLiteAdapter;
 ListView listContent;
 
 SimpleCursorAdapter cursorAdapter;
 Cursor cursor;
 
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.main);
      
       inputContent1 = (EditText)findViewById(R.id.content1);
       inputContent2 = (EditText)findViewById(R.id.content2);
       buttonAdd = (Button)findViewById(R.id.add);
       buttonDeleteAll = (Button)findViewById(R.id.deleteall);
      
       listContent = (ListView)findViewById(R.id.contentlist);

       mySQLiteAdapter = new SQLiteAdapter(this);
       mySQLiteAdapter.openToWrite();

       cursor = mySQLiteAdapter.queueAll();
       String[] from = new String[]{SQLiteAdapter.KEY_ID, SQLiteAdapter.KEY_CONTENT1, SQLiteAdapter.KEY_CONTENT2};
       int[] to = new int[]{R.id.id, R.id.text1, R.id.text2};
       cursorAdapter =
        new SimpleCursorAdapter(this, R.layout.row, cursor, from, to);
       listContent.setAdapter(cursorAdapter);
       listContent.setOnItemClickListener(listContentOnItemClickListener);
      
       buttonAdd.setOnClickListener(buttonAddOnClickListener);
       buttonDeleteAll.setOnClickListener(buttonDeleteAllOnClickListener);
      
   }
  
   Button.OnClickListener buttonAddOnClickListener
   = new Button.OnClickListener(){

  @Override
  public void onClick(View arg0) {
   // TODO Auto-generated method stub
   String data1 = inputContent1.getText().toString();
   String data2 = inputContent2.getText().toString();
   mySQLiteAdapter.insert(data1, data2);
   updateList();
  }
    
   };
  
   Button.OnClickListener buttonDeleteAllOnClickListener
   = new Button.OnClickListener(){

  @Override
  public void onClick(View arg0) {
   // TODO Auto-generated method stub
   mySQLiteAdapter.deleteAll();
   updateList();
  }
    
   };
  
   private ListView.OnItemClickListener listContentOnItemClickListener
   = new ListView.OnItemClickListener(){

  @Override
  public void onItemClick(AdapterView<?> parent, View view, int position,
    long id) {
   // TODO Auto-generated method stub
   
   Cursor cursor = (Cursor) parent.getItemAtPosition(position);
   final int item_id = cursor.getInt(cursor.getColumnIndex(SQLiteAdapter.KEY_ID));
           String item_content1 = cursor.getString(cursor.getColumnIndex(SQLiteAdapter.KEY_CONTENT1));
           String item_content2 = cursor.getString(cursor.getColumnIndex(SQLiteAdapter.KEY_CONTENT2));
          
           AlertDialog.Builder myDialog
           = new AlertDialog.Builder(AndroidSQLite.this);
          
           myDialog.setTitle("Delete/Edit?");
          
           TextView dialogTxt_id = new TextView(AndroidSQLite.this);
           LayoutParams dialogTxt_idLayoutParams
            = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
           dialogTxt_id.setLayoutParams(dialogTxt_idLayoutParams);
           dialogTxt_id.setText("#" + String.valueOf(item_id));
          
           final EditText dialogC1_id = new EditText(AndroidSQLite.this);
           LayoutParams dialogC1_idLayoutParams
            = new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);
           dialogC1_id.setLayoutParams(dialogC1_idLayoutParams);
           dialogC1_id.setText(item_content1);
          
           final EditText dialogC2_id = new EditText(AndroidSQLite.this);
           LayoutParams dialogC2_idLayoutParams
            = new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);
           dialogC2_id.setLayoutParams(dialogC2_idLayoutParams);
           dialogC2_id.setText(item_content2);
          
           LinearLayout layout = new LinearLayout(AndroidSQLite.this);
           layout.setOrientation(LinearLayout.VERTICAL);
           layout.addView(dialogTxt_id);
           layout.addView(dialogC1_id);
           layout.addView(dialogC2_id);
           myDialog.setView(layout);
          
           myDialog.setPositiveButton("Delete", new DialogInterface.OnClickListener() {
               // do something when the button is clicked
               public void onClick(DialogInterface arg0, int arg1) {
                mySQLiteAdapter.delete_byID(item_id);
          updateList();
                }
               });
          
           myDialog.setNeutralButton("Update", new DialogInterface.OnClickListener() {
               // do something when the button is clicked
               public void onClick(DialogInterface arg0, int arg1) {
                String value1 = dialogC1_id.getText().toString();
                String value2 = dialogC2_id.getText().toString();
                mySQLiteAdapter.update_byID(item_id, value1, value2);
          updateList();
                }
               });
          
           myDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
               // do something when the button is clicked
               public void onClick(DialogInterface arg0, int arg1) {
       
                }
               });
          
           myDialog.show();
          
          
  }};

 @Override
 protected void onDestroy() {
  // TODO Auto-generated method stub
  super.onDestroy();
  mySQLiteAdapter.close();
 }

 private void updateList(){
  cursor.requery();
   }

}