自己的SQLite数据库和onUpgrade [英] Own SQLite Database and onUpgrade
问题描述
我用这个教程,以创建和填充自己的SQLite数据库为Android。 的http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications
I've used this tutorial in order to create and populate my own SQLite database for android. http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications
不过,使用这些精确的方法意味着数据库犯规具有以下code升级
However, using these exact methods mean that the database doesnt upgrade with the following code
private static final int DB_Version = 2;
public DbConnector(Context context){
super(context, DB_Name, null, DB_Version);
this.context = context;
}
其实方法onUpgrade()不会被调用:(
In fact the method onUpgrade() is never called :(
感谢您的帮助
推荐答案
下面是答案感谢乔Masilotti上 <一href="http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/comment-page-2/" rel="nofollow">http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/comment-page-2/
Here is the answer thanks to Joe Masilotti on http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/comment-page-2/
private static final int DATABASE_VERSION = 1;
构造函数更改为:
Change the constructor to:
public DataBaseHelper(Context context) {
super(context, DB_NAME, null, DATABASE_VERSION);
this.myContext = context;
}
更改的CreateDatabase
来(感谢@kondortek):
Change the createDataBase
to (thanks @kondortek):
public void createDataBase() throws IOException {
boolean dbExist = checkDataBase();
if (dbExist) {
Log.v("DB Exists", "db exists");
// By calling this method here onUpgrade will be called on a
// writeable database, but only if the version number has been
// bumped
this.getWritableDatabase();
}
dbExist = checkDataBase();
if (!dbExist) {
// By calling this method and empty database will be created into
// the default system path of your application so we are gonna be
// able to overwrite that database with our database.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
修改 onUpgrade
来:
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
if (newVersion > oldVersion)
Log.v("Database Upgrade", "Database version higher than old.");
myContext.deleteDatabase(DB_NAME);
}
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