问使用初始数据创建和引导数据库

EN

/***
  Copyright (c) 2008-2012 CommonsWare, LLC
  Licensed under the Apache License, Version 2.0 (the "License"); you may not
  use this file except in compliance with the License. You may obtain   a copy
  of the License at http://www.apache.org/licenses/LICENSE-2.0. Unless required
  by applicable law or agreed to in writing, software distributed under the
  License is distributed on an "AS IS" BASIS,   WITHOUT WARRANTIES OR CONDITIONS
  OF ANY KIND, either express or implied. See the License for the specific
  language governing permissions and limitations under the License.

  From _The Busy Coder's Guide to Android Development_
    https://commonsware.com/Android
 */

package com.commonsware.android.constants;

import android.content.ContentValues;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.hardware.SensorManager;

public class DatabaseHelper extends SQLiteOpenHelper {
  private static final String DATABASE_NAME="constants.db";
  private static final int SCHEMA=1;
  static final String TITLE="title";
  static final String VALUE="value";
  static final String TABLE="constants";

  public DatabaseHelper(Context context) {
    super(context, DATABASE_NAME, null, SCHEMA);
  }

  @Override
  public void onCreate(SQLiteDatabase db) {
    db.execSQL("CREATE TABLE constants (title TEXT, value REAL);");

    ContentValues cv=new ContentValues();

    cv.put(TITLE, "Gravity, Death Star I");
    cv.put(VALUE, SensorManager.GRAVITY_DEATH_STAR_I);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Earth");
    cv.put(VALUE, SensorManager.GRAVITY_EARTH);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Jupiter");
    cv.put(VALUE, SensorManager.GRAVITY_JUPITER);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Mars");
    cv.put(VALUE, SensorManager.GRAVITY_MARS);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Mercury");
    cv.put(VALUE, SensorManager.GRAVITY_MERCURY);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Moon");
    cv.put(VALUE, SensorManager.GRAVITY_MOON);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Neptune");
    cv.put(VALUE, SensorManager.GRAVITY_NEPTUNE);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Pluto");
    cv.put(VALUE, SensorManager.GRAVITY_PLUTO);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Saturn");
    cv.put(VALUE, SensorManager.GRAVITY_SATURN);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Sun");
    cv.put(VALUE, SensorManager.GRAVITY_SUN);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, The Island");
    cv.put(VALUE, SensorManager.GRAVITY_THE_ISLAND);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Uranus");
    cv.put(VALUE, SensorManager.GRAVITY_URANUS);
    db.insert(TABLE, TITLE, cv);

    cv.put(TITLE, "Gravity, Venus");
    cv.put(VALUE, SensorManager.GRAVITY_VENUS);
    db.insert(TABLE, TITLE, cv);
  }

  @Override
  public void onUpgrade(SQLiteDatabase db, int oldVersion,
                        int newVersion) {
    throw new RuntimeException("How did we get here?");
  }
}