SQLite的一个例子

main.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="fill_parent"  

    android:orientation="vertical" >  

    <EditText   

        android:id="@+id/bookname"  

        android:layout_width="fill_parent"  

        android:layout_height="wrap_content"  

        />  

    <EditText   

        android:id="@+id/author"  

        android:layout_width="fill_parent"  

        android:layout_height="wrap_content"  

        />  

    <ListView  

        android:id="@+id/booklist"  

        android:layout_width="fill_parent"  

        android:layout_height="wrap_content"  

        >  

    </ListView>  

</LinearLayout>  

BOOKS_DB.java：

package com.wangxin;  

  

import android.content.ContentValues;  

import android.content.Context;  

import android.database.Cursor;  

import android.database.sqlite.SQLiteDatabase;  

import android.database.sqlite.SQLiteDatabase.CursorFactory;  

import android.database.sqlite.SQLiteOpenHelper;  

  

public class BooksDB extends SQLiteOpenHelper {  

    private final static String DATABASE_NAME = "BOOKS.db";  

    private final static int DATABASE_VERSION = 1;  

    public final static String TABLE_NAME = "books_table";  

    public final static String BOOK_ID = "book_id";  

    public final static String BOOK_NAME = "book_name";  

    public final static String BOOK_AUTHOR = "book_author";  

  

    public BooksDB(Context context) {  

        super(context, DATABASE_NAME, null, DATABASE_VERSION);  

    }  

  

    public BooksDB(Context context, String name, CursorFactory factory,  

            int version) {  

        super(context, name, factory, version);  

        // TODO Auto-generated constructor stub  

    }  

  

    @Override  

    public void onCreate(SQLiteDatabase db) {  

        // TODO Auto-generated method stub  

        String sql = "CREATE TABLE " + TABLE_NAME + "(" + BOOK_ID  

                + " INTEGER primary key autoincrement, " + BOOK_NAME + " text "  

                + BOOK_AUTHOR + "text);";  

        db.execSQL(sql);  

    }  

  

    @Override  

    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {  

        // TODO Auto-generated method stub  

        String sql = "DROP TABLE IF EXISTS" + TABLE_NAME;  

        db.execSQL(sql);  

        onCreate(db);  

    }  

  

    public Cursor select() {  

        SQLiteDatabase db = this.getReadableDatabase();  

        Cursor cursor = db  

                .query(TABLE_NAME, null, null, null, null, null, null);  

        return cursor;  

    }  

  

    public long insert(String bookname, String author) {  

        SQLiteDatabase db = this.getWritableDatabase();  

        ContentValues cv = new ContentValues();  

        cv.put(BOOK_NAME, bookname);  

        cv.put(BOOK_AUTHOR, author);  

        long row = db.insert(TABLE_NAME, null, cv);  

        return row;  

    }  

  

    public void delete(int id) {  

        SQLiteDatabase db = this.getWritableDatabase();  

        String where = BOOK_ID + "=?";  

        String[] whereValue = { Integer.toString(id) };  

        db.delete(TABLE_NAME, where, whereValue);  

    }  

  

    public void update(int id, String bookname, String author) {  

        SQLiteDatabase db = this.getWritableDatabase();  

        String where = BOOK_ID + "=?";  

        String[] whereValue = { Integer.toString(id) };  

  

        ContentValues cv = new ContentValues();  

        cv.put(BOOK_NAME, bookname);  

        cv.put("BOOK_AHTHOR", author);  

        db.update(TABLE_NAME, cv, where, whereValue);  

    }  

}  

SQLiteDemoActivity.java

package com.wangxin;  

  

import android.app.Activity;  

import android.content.Context;  

import android.database.Cursor;  

import android.os.Bundle;  

import android.view.Menu;  

import android.view.MenuItem;  

import android.view.View;  

import android.view.ViewGroup;  

import android.widget.AdapterView;  

import android.widget.AdapterView.OnItemClickListener;  

import android.widget.BaseAdapter;  

import android.widget.EditText;  

import android.widget.ListAdapter;  

import android.widget.ListView;  

import android.widget.SimpleAdapter;  

import android.widget.TextView;  

import android.widget.Toast;  

  

public class SQLiteDemoActivity extends Activity {  

    /** Called when the activity is first created. */  

    private EditText BookName = null;  

    private EditText BookAuthor = null;  

    private ListView BooksList = null;  

    private BooksDB mBooksDB;  

    private Cursor mCursor;  

  

    private int BOOK_ID = 0;  

    protected final static int MENU_ADD = Menu.FIRST;  

    protected final static int MENU_DELETE = Menu.FIRST + 1;  

    protected final static int MENU_UPDATE = Menu.FIRST + 2;  

  

    @Override  

    public void onCreate(Bundle savedInstanceState) {  

        super.onCreate(savedInstanceState);  

        setContentView(R.layout.main);  

        setUpViews();  

    }  

  

    public void setUpViews() {  

        mBooksDB = new BooksDB(this);  

        mCursor = mBooksDB.select();  

  

        BookName = (EditText) findViewById(R.id.bookname);  

        BookAuthor = (EditText) findViewById(R.id.author);  

        BooksList = (ListView) findViewById(R.id.booklist);  

  

        BooksList.setAdapter(new BooksListAdapter(this, mCursor));  

        BooksList.setOnItemClickListener(new onItemClickListener());  

    }  

  

    public boolean onCreateOptionsMenu(Menu menu) {  

        super.onCreateOptionsMenu(menu);  

  

        menu.add(Menu.NONE, MENU_ADD, 0, "ADD");  

        menu.add(Menu.NONE, MENU_DELETE, 0, "DELETE");  

        menu.add(Menu.NONE, MENU_DELETE, 0, "UPDATE");  

        return true;  

    }  

  

    public boolean onOptionsItemSelected(MenuItem item) {  

        super.onOptionsItemSelected(item);  

        switch (item.getItemId()) {  

        case MENU_ADD:  

            add();  

            break;  

        case MENU_DELETE:  

            delete();  

            break;  

        case MENU_UPDATE:  

            update();  

            break;  

        }  

        return true;  

    }  

  

    public void add() {  

        String bookname = BookName.getText().toString();  

        String author = BookAuthor.getText().toString();  

        // 书名和作者都不能为空，或者退出  

        if (bookname.equals("") || author.equals("")) {  

            return;  

        }  

        mBooksDB.insert(bookname, author);  

        mCursor.requery();  

        BooksList.invalidateViews();  

        BookName.setText("");  

        BookAuthor.setText("");  

        Toast.makeText(this, "Add Successed!", Toast.LENGTH_SHORT).show();  

    }  

  

    public void delete() {  

        if (BOOK_ID == 0) {  

            return;  

        }  

        mBooksDB.delete(BOOK_ID);  

        mCursor.requery();  

        BooksList.invalidateViews();  

        BookName.setText("");  

        BookAuthor.setText("");  

        Toast.makeText(this, "Delete Successed!", Toast.LENGTH_SHORT).show();  

    }  

  

    public void update() {  

        String bookname = BookName.getText().toString();  

        String author = BookAuthor.getText().toString();  

        // 书名和作者都不能为空，或者退出  

        if (bookname.equals("") || author.equals("")) {  

            return;  

        }  

        mBooksDB.update(BOOK_ID, bookname, author);  

        mCursor.requery();  

        BooksList.invalidateViews();  

        BookName.setText("");  

        BookAuthor.setText("");  

        Toast.makeText(this, "Update Successed!", Toast.LENGTH_SHORT).show();  

    }  

  

/*  public void onItemClicked(AdapterView<?> parent, View view, int position, 

            long id) { 

 

        mCursor.moveToPosition(position); 

        BOOK_ID = mCursor.getInt(0); 

        BookName.setText(mCursor.getString(1)); 

        BookAuthor.setText(mCursor.getString(2)); 

 

    }*/  

  

    public class BooksListAdapter extends BaseAdapter {  

        private Context mContext;  

        private Cursor mCursor;  

  

        public BooksListAdapter(Context context, Cursor cursor) {  

            mContext = context;  

            mCursor = cursor;  

        }  

  

        public int getCount() {  

            return mCursor.getCount();  

        }  

  

        public Object getItem(int position) {  

            return null;  

        }  

  

        public long getItemId(int position) {  

            return 0;  

        }  

  

        public View getView(int position, View convertView, ViewGroup parent) {  

            TextView mTextView = new TextView(mContext);  

            mCursor.moveToPosition(position);  

            mTextView.setText(mCursor.getString(1) + "___"  

                    + mCursor.getString(2));  

            return mTextView;  

        }  

    }  

      

    class onItemClickListener implements OnItemClickListener{  

  

        public void onItemClick(AdapterView<?> parent, View view, int position,  

                long id) {  

            // TODO Auto-generated method stub  

  

            mCursor.moveToPosition(position);  

            BOOK_ID = mCursor.getInt(0);  

            BookName.setText(mCursor.getString(1));  

            BookAuthor.setText(mCursor.getString(2));  

        }  

          

    }  

}