DatabaseTest

1.效果图

2.代码

package com.example.databasetest;import android.app.Activity;import android.content.ContentValues;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import android.os.Bundle;import android.util.Log;import android.view.Menu;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;public class MainActivity extends Activity{private MyDatabaseHelper dbHelper;@Overrideprotected void onCreate(Bundle savedInstanceState){super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);dbHelper=new MyDatabaseHelper(this, "BookStore.db", null, 2);Button createDatabase=(Button)findViewById(R.id.create_database);createDatabase.setOnClickListener(new OnClickListener(){@Overridepublic void onClick(View v){// TODO Auto-generated method stubdbHelper.getWritableDatabase();}});Button addData=(Button) findViewById(R.id.add_data);addData.setOnClickListener(new OnClickListener(){public void onClick(View v){SQLiteDatabase db=dbHelper.getWritableDatabase();ContentValues values=new ContentValues();// 开始组装第一条数据values.put("name", "The Da Vinci Code");values.put("author", "Dan Brown");values.put("pages", 454);values.put("price", 16.96);db.insert("Book", null, values); // 插入第一条数据values.clear();// 开始组装第二条数据values.put("name", "The Lost Symbol");values.put("author", "Dan Brown");values.put("pages", 510);values.put("price", 19.95);db.insert("Book", null, values); // 插入第二条数据}});Button updateData=(Button)findViewById(R.id.update_data);updateData.setOnClickListener(new OnClickListener(){public void onClick(View v){SQLiteDatabase db=dbHelper.getWritableDatabase();ContentValues values=new ContentValues();values.put("price", 10.99);db.update("Book", values, "name=?", new String[]{"The Da Vinci Code"});}});Button deleteButton=(Button)findViewById(R.id.delete_data);deleteButton.setOnClickListener(new OnClickListener(){public void onClick(View v){SQLiteDatabase db=dbHelper.getWritableDatabase();db.delete("Book",  "pages > ?", new String[]{"500"});}});Button queryButton=(Button)findViewById(R.id.query_data);queryButton.setOnClickListener(new OnClickListener(){public void onClick(View v){SQLiteDatabase db=dbHelper.getWritableDatabase();Cursor cursor=db.query("Book", null, null, null, null, null, null);if (cursor.moveToFirst()){do{String name=cursor.getString(cursor.getColumnIndex("name"));String author=cursor.getString(cursor.getColumnIndex("author"));int pages=cursor.getInt(cursor.getColumnIndex("pages"));double price=cursor.getDouble(cursor.getColumnIndex("price"));Log.d("MainActivity", "book name is "+name);Log.d("MainActivity", "book author is "+author);Log.d("MainActivity", "book pages is "+pages);Log.d("MainActivity", "book price is "+price);}while(cursor.moveToNext());}cursor.close();}});}@Overridepublic boolean onCreateOptionsMenu(Menu menu){// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}}

package com.example.databasetest;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteDatabase.CursorFactory;import android.database.sqlite.SQLiteOpenHelper;import android.widget.Toast;public class MyDatabaseHelper extends SQLiteOpenHelper{public static final String CREATE_BOOK="create table book("        +"id integer primary key autoincrement,"+"author text,"+"price real,"+"pages integer,"+"name text)";public static final String CREATE_CATEGORY="create table category("+"id integer primary key autoincrement,"+"category_name text,"+"category_code integer)"; private Context mContext;public MyDatabaseHelper(Context context,String name,CursorFactoryfactory,int version){super(context,name,factory,version);mContext=context;}public void onCreate(SQLiteDatabase db){db.execSQL(CREATE_BOOK);db.execSQL(CREATE_CATEGORY);Toast.makeText(mContext, "Create succeeded", Toast.LENGTH_SHORT).show();}public void onUpgrade(SQLiteDatabase db,int oldVersion,int newVersion){db.execSQL("drop table if exists Book");db.execSQL("drop table if exists Ctegory");onCreate(db);}}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >    <Button        android:id="@+id/create_database"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="Create database" />    <Button        android:id="@+id/add_data"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="Add data" />    <Button        android:id="@+id/update_data"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="Update data" />     <Button        android:id="@+id/delete_data"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="Delete data" />     <Button        android:id="@+id/query_data"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="Query data" /></LinearLayout>