安卓：从资产问题复制SQLite数据库（我有一个数据库，没有任何田部毕竟）数据库、没有任何、我有一个、资产

2023-09-07 10:05:42 作者：灬諟刂抿酒zυιㄣ

我试图使一个DataAdapter的扩展SQLiteOpenHelper。贝娄是code：

I'm trying to make an dataAdapter extend SQLiteOpenHelper. Bellow is the code:

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.annotation.SuppressLint;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import com.muoiot.enlistening.idefined.*;
import com.muoiot.enlistening.utilities.MsgUtils;

public class DbAdapter extends SQLiteOpenHelper implements DB_INFO, DB_USER, DB_QUESTION {

    public static String defaultDbPath = "";
    protected SQLiteDatabase databaseControl;
    private Context context = null;

    public DbAdapter(Context context, String name, CursorFactory factory, int version) {
        super(context, name, factory, version);
        this.context = context;
        defaultDbPath = "/data/data/" + context.getApplicationContext().getPackageName() + "/databases/";
    }

    /***********************************************************************************/
    // This function auto call at the first time when the database was not found.
    /***********************************************************************************/   
    @Override
    public void onCreate(SQLiteDatabase db) {

        MsgUtils.DB("Don't have database, need to copy from asset");
        try {
            copyDataBase();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
    /***********************************************************************************/
    // This function auto call when the database has been opened.
    /***********************************************************************************/   
    @Override
    public void onOpen(SQLiteDatabase db){
        MsgUtils.DB(" AAAAAAAAAAAAAAAAAAAAAAAAA has been opened!!!");
    }

    /***********************************************************************************/
    // Copy database
    /***********************************************************************************/       
    private void copyDataBase() throws IOException {

        // Open your local db as the input stream
        InputStream myInput = this.context.getAssets().open(DB_NAME);

        // Path to the just created empty db
        String outFileName = defaultDbPath + DB_NAME;

        // Open the empty db as the output stream
        OutputStream myOutput = new FileOutputStream(outFileName);

        // transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer)) > 0) {
            myOutput.write(buffer, 0, length);
        }

        // Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();

    }

    /***********************************************************************************/
    // Open and close database 
    /***********************************************************************************/   
    public void openDatabase(){
        databaseControl = this.getWritableDatabase();
    }

    public void closeDatabase(){
        this.getWritableDatabase().close();
    }

}

而且，现在我有copyDataBase功能的问题。我总是与任何表得到一个数据库。（我的手机扎根，所以我复制回从数据/数据//数据库的数据库审核）。

And, now I have an issue with copyDataBase function. I always get an database with out any table. (my phone was rooted, so I copy back the database from data/data//databases to review).

我是什么错在这里？谁能给我个忙吗？

What am I wrong here? Anyone can give me a hand?

安卓：从资产问题复制SQLite数据库（我有一个数据库，没有任何田部毕竟）数据库、没有任何、我有一个、资产

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