java - SQLiteAssetHelper :Couldn't open database for writing (will try read-only)

Question

这个问题已经被人们问过了，但是通过他们中的许多人的步骤我仍然无法解决这个问题，我的应用程序在模拟器上运行良好但在真实设备上运行不正常并提供以下内容2 个异常，第一个异常是第二个异常的主要来源，我想存在一些权限问题。我已经添加了

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

到 list 文件，但我得到了相同的结果。我的数据库非常简单，只有一张表。我还添加了“android_metadata”表并将我的其他表的 id 字段编辑为“_id”。我确定我的数据库存在于 Assets 文件夹中。

如有任何帮助，我们将不胜感激。

第一个异常

02-24 12:58:10.067: E/SQLiteAssetHelper(7107): Couldn't open Shajra for writing (will try read-only):
02-24 12:58:10.067: E/SQLiteAssetHelper(7107): com.readystatesoftware.sqliteasset.SQLiteAssetHelper$SQLiteAssetException: Missing databases/Shajra file (or .zip, .gz archive) in assets, or target folder not writable
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.content.res.AssetManager.openAsset(Native Method)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.content.res.AssetManager.open(AssetManager.java:325)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.content.res.AssetManager.open(AssetManager.java:299)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at com.readystatesoftware.sqliteasset.SQLiteAssetHelper.copyDatabaseFromAssets(SQLiteAssetHelper.java:436)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at com.readystatesoftware.sqliteasset.SQLiteAssetHelper.createOrOpenDatabase(SQLiteAssetHelper.java:400)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at com.readystatesoftware.sqliteasset.SQLiteAssetHelper.getWritableDatabase(SQLiteAssetHelper.java:176)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at com.readystatesoftware.sqliteasset.SQLiteAssetHelper.getReadableDatabase(SQLiteAssetHelper.java:254)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at com.nannandotcom.MainActivity.onCreate(MainActivity.java:27)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1072)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1836)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1893)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.app.ActivityThread.access$1500(ActivityThread.java:135)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1054)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.os.Handler.dispatchMessage(Handler.java:99)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.os.Looper.loop(Looper.java:150)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at android.app.ActivityThread.main(ActivityThread.java:4389)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at java.lang.reflect.Method.invokeNative(Native Method)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at java.lang.reflect.Method.invoke(Method.java:507)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:849)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:607)
02-24 12:58:10.067: E/SQLiteAssetHelper(7107):  at dalvik.system.NativeStart.main(Native Method)

第二个异常(exception)

02-24 12:58:10.077: E/Database(7107): dbopen(): sqlite3_open_v2("/data/data/com.example.nannandotcom/databases/Shajra", &handle, 1, NULL) failed
02-24 12:58:10.077: E/Database(7107): dbopen(): errno = 2, error message = No such file or directory
02-24 12:58:10.077: D/AndroidRuntime(7107): Shutting down VM
02-24 12:58:10.077: W/dalvikvm(7107): threadid=1: thread exiting with uncaught exception (group=0x4011f5a0)
02-24 12:58:10.108: E/AndroidRuntime(7107): FATAL EXCEPTION: main
02-24 12:58:10.108: E/AndroidRuntime(7107): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.nannandotcom/com.nannandotcom.MainActivity}: android.database.sqlite.SQLiteException: unable to open database file
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1872)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1893)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.app.ActivityThread.access$1500(ActivityThread.java:135)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1054)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.os.Handler.dispatchMessage(Handler.java:99)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.os.Looper.loop(Looper.java:150)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.app.ActivityThread.main(ActivityThread.java:4389)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at java.lang.reflect.Method.invokeNative(Native Method)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at java.lang.reflect.Method.invoke(Method.java:507)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:849)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:607)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at dalvik.system.NativeStart.main(Native Method)
02-24 12:58:10.108: E/AndroidRuntime(7107): Caused by: android.database.sqlite.SQLiteException: unable to open database file
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.database.sqlite.SQLiteDatabase.dbopen(Native Method)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1962)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:906)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at com.readystatesoftware.sqliteasset.SQLiteAssetHelper.getReadableDatabase(SQLiteAssetHelper.java:264)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at com.nannandotcom.MainActivity.onCreate(MainActivity.java:27)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1072)
02-24 12:58:10.108: E/AndroidRuntime(7107):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1836)
02-24 12:58:10.108: E/AndroidRuntime(7107):     ... 11 more

数据库助手

package com.nannandotcom;

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

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;

import com.nannandotcom.model.ProfileBean;
import com.readystatesoftware.sqliteasset.SQLiteAssetHelper;

public class DatabaseHelper extends SQLiteAssetHelper {

    private static final String DATABASE_NAME = "Shajra";
    private static final int DATABASE_VERSION = 1;

    private Context context;

    public DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
        this.context = context;
    }

    public void copyDatabase() throws IOException{
    //  SQLiteDatabase checkDB = SQLiteDatabase.openDatabase(context.getAssets().+(DATABASE_NAME), null, SQLiteDatabase.OPEN_READONLY);
    //  checkDB.close();
    InputStream myInput = context.getAssets().open(DATABASE_NAME);      
    String outFileName =  "/data/data/"+ context.getPackageName() + "/databases/" + DATABASE_NAME;     
    OutputStream myOutput = new FileOutputStream(outFileName);

    byte[] buffer = new byte[1024];
    int length;
    while ((length = myInput.read(buffer))>0){
        myOutput.write(buffer, 0, length);
    }

    myOutput.flush();
    myOutput.close();
    myInput.close();
    }

    public ProfileBean getProfileBean(SQLiteDatabase database,int id){
        ProfileBean profileBean = new ProfileBean();
        try {
            Cursor c = database.query("Profiles",
                    new String[]{"_id","Name","Qualification","WorkingAt","LivesAt","MaritalStatus","NumberOfChildren",
                    "Telephone","Email","Picture","MarriedTo","Father","Mother","DOB","Gender"},
                    "_id=?",
                    new String[]{Integer.toString(id)},null, null, null);
            if (c != null ) {
                if  (c.moveToFirst()) {
                    do {

                    }while (c.moveToNext());
                } 
            }   
        }
        catch(Exception e){
            e.printStackTrace();
        }
        return profileBean;
    }
}

主要 Activity

package com.nannandotcom;

import java.io.IOException;
import com.example.nannandotcom.R;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        DatabaseHelper databaseHelper = new DatabaseHelper(this);
        SQLiteDatabase database = databaseHelper.getReadableDatabase();

        try {
            databaseHelper.copyDatabase();
    }   
        }catch(SQLException sqle){

            throw sqle;

        }
        }
        catch(Exception e){
            Log.e("MainActivity", e.getMessage());
            e.printStackTrace();
        }

        final EditText enterName = (EditText) findViewById(R.id.editText1);
        Button submit = (Button) findViewById(R.id.button1);
        submit.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                Intent mainActivityIntent = new   Intent(MainActivity.this, Welcome.class);
                mainActivityIntent.putExtra("userName", enterName.getText().toString());
                startActivity(mainActivityIntent);
            }
        });
    }

    @Override
    public 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;
    }

}

Answer 1

我认为您在 DATABASE_NAME 中缺少数据库扩展。

因此根据 Assets 目录给出特定的 DATABASE_NAME 和扩展名。

替换

private static final String DATABASE_NAME = "Shajra"; 

与

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

或者

private static final String DATABASE_NAME = "Shajra.sqlite";