我已经在网站上阅读了有关此问题的各种内容,但无法弄清楚。我正在为此应用程序使用预构建数据库。我正在为此应用程序使用 bean 形软糖。

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="com.example.quotes"
        android:versionCode="1"
        android:versionName="1.0" >

        <uses-sdk
            android:minSdkVersion="8"
            android:targetSdkVersion="17" />

        <application
            android:allowBackup="true"
            android:icon="@drawable/ic_launcher"
            android:label="@string/app_name"
            android:theme="@style/AppTheme" >
            <activity
                android:name="com.example.quotes.MainActivity"
                android:label="@string/app_name" >
                <intent-filter>
                    <action android:name="android.intent.action.MAIN" />

                    <category android:name="android.intent.category.LAUNCHER" />
                </intent-filter>
            </activity>
        </application>

    </manifest>

Logcat输出

根据logcat它是由SQLiteCantOpenDatabaseException引起的
06-10 23:07:01.831: E/Trace(4419): error opening trace file: No such file or directory (2)
06-10 23:07:03.611: E/SQLiteLog(4419): (14) cannot open file at line 30176 of [00bb9c9ce4]
06-10 23:07:03.621: E/SQLiteLog(4419): (14) os_unix.c:30176: (2) open(/data/data/com.example.quotes/databasesQuotesdb) -
06-10 23:07:03.641: E/SQLiteDatabase(4419): Failed to open database '/data/data/com.example.quotes/databasesQuotesdb'.
06-10 23:07:03.641: E/SQLiteDatabase(4419): android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:209)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:804)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:789)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:694)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:669)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at com.example.quotes.DataBaseHelper.checkDataBase(DataBaseHelper.java:94)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at com.example.quotes.DataBaseHelper.createDataBase(DataBaseHelper.java:58)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at com.example.quotes.MainActivity.onCreate(MainActivity.java:34)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.app.Activity.performCreate(Activity.java:5104)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.os.Looper.loop(Looper.java:137)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at android.app.ActivityThread.main(ActivityThread.java:5041)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at java.lang.reflect.Method.invokeNative(Native Method)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at java.lang.reflect.Method.invoke(Method.java:511)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
06-10 23:07:03.641: E/SQLiteDatabase(4419):     at dalvik.system.NativeStart.main(Native Method)
06-10 23:07:03.731: E/SQLiteLog(4419): (14) cannot open file at line 30176 of [00bb9c9ce4]
06-10 23:07:03.731: E/SQLiteLog(4419): (14) os_unix.c:30176: (2) open(/data/data/com.example.quotes/databasesQuotesdb) -
06-10 23:07:03.781: E/SQLiteDatabase(4419): Failed to open database '/data/data/com.example.quotes/databasesQuotesdb'.
06-10 23:07:03.781: E/SQLiteDatabase(4419): android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:209)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:804)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:789)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:694)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:669)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at com.example.quotes.DataBaseHelper.openDataBase(DataBaseHelper.java:145)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at com.example.quotes.MainActivity.onCreate(MainActivity.java:44)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.app.Activity.performCreate(Activity.java:5104)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.os.Looper.loop(Looper.java:137)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at android.app.ActivityThread.main(ActivityThread.java:5041)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at java.lang.reflect.Method.invokeNative(Native Method)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at java.lang.reflect.Method.invoke(Method.java:511)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
06-10 23:07:03.781: E/SQLiteDatabase(4419):     at dalvik.system.NativeStart.main(Native Method)
06-10 23:07:03.791: D/AndroidRuntime(4419): Shutting down VM
06-10 23:07:03.791: W/dalvikvm(4419): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
06-10 23:07:03.831: E/AndroidRuntime(4419): FATAL EXCEPTION: main
06-10 23:07:03.831: E/AndroidRuntime(4419): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.quotes/com.example.quotes.MainActivity}: android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.os.Handler.dispatchMessage(Handler.java:99)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.os.Looper.loop(Looper.java:137)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.ActivityThread.main(ActivityThread.java:5041)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at java.lang.reflect.Method.invokeNative(Native Method)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at java.lang.reflect.Method.invoke(Method.java:511)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at dalvik.system.NativeStart.main(Native Method)
06-10 23:07:03.831: E/AndroidRuntime(4419): Caused by: android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteConnection.nativeOpen(Native Method)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:209)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteConnection.open(SQLiteConnection.java:193)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteConnectionPool.openConnectionLocked(SQLiteConnectionPool.java:463)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:185)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteConnectionPool.open(SQLiteConnectionPool.java:177)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteDatabase.openInner(SQLiteDatabase.java:804)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteDatabase.open(SQLiteDatabase.java:789)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:694)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:669)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at com.example.quotes.DataBaseHelper.openDataBase(DataBaseHelper.java:145)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at com.example.quotes.MainActivity.onCreate(MainActivity.java:44)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.Activity.performCreate(Activity.java:5104)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
06-10 23:07:03.831: E/AndroidRuntime(4419):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
06-10 23:07:03.831: E/AndroidRuntime(4419):     ... 11 more
06-10 23:07:04.083: D/dalvikvm(4419): GC_CONCURRENT freed 203K, 11% free 2676K/3000K, paused 25ms+18ms, total 306ms
06-10 23:07:07.811: I/Process(4419): Sending signal. PID: 4419 SIG: 9

DataBaseHelper.java
public class DataBaseHelper extends SQLiteOpenHelper{

    //The Android's default system path of your application database.
    private static String DB_PATH = "/data/data/com.example.quotes/databases";

    private static String DB_NAME = "Quotesdb";

    // Table Names of Data Base.
    static final String TABLE_Name = "Quotes";

    // Contacts Table Columns names
    //private static final String _Id = "_Id";
    //private static final String quotes = "quotes";
    //private static final String author = "author";

    private SQLiteDatabase myDataBase;

    private final Context myContext;

    /**
     * Constructor
     * Takes and keeps a reference of the passed context in order to access to the application assets and resources.
     * @param context
     */
    public DataBaseHelper(Context context) {
        super(context, DB_NAME, null, 1);
        this.myContext = context;
    }

    /**
     * Creates a empty database on the system and rewrites it with your own database.
     * */
    public void createDataBase() throws IOException{

        boolean dbExist = checkDataBase();
        SQLiteDatabase db_Read = null;

        if(dbExist){
            //do nothing - database already exist
        }else{
            //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.
            db_Read = this.getReadableDatabase();
            db_Read.close();

            try {
                copyDataBase();
            } catch (IOException e) {
                //throw new Error("Error copying database");
                e.toString();
            }
        }
    }

    /**
     * Check if the database already exist to avoid re-copying the file each time you open the application.
     * @return true if it exists, false if it doesn't
     */
    private boolean checkDataBase(){

        SQLiteDatabase checkDB = null;

        try{
            String myPath = DB_PATH + DB_NAME;
            checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
        }catch(SQLiteException e){
            //database does't exist yet.
        }

        if(checkDB != null){
            checkDB.close();
        }

        return checkDB != null ? true : false;
    }

    /**
     * Copies your database from your local assets-folder to the just created empty database in the
     * system folder, from where it can be accessed and handled.
     * This is done by transfering bytestream.
     * */
    private void copyDataBase() throws IOException{

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

        // Path to the just created empty db
        String outFileName = DB_PATH + 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();
    }

    public void openDataBase() throws SQLException{
        //Open the database
        String myPath = DB_PATH + DB_NAME;
        myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);

    }

    @Override
    public synchronized void close() {
        if(myDataBase != null)
            myDataBase.close();

        super.close();
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        // TODO Auto-generated method stub
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // TODO Auto-generated method stub
    }

    /*// Getting single contact
    public List<Quotes> getQuote(int id) {
        ArrayList<Quotes>();
        getReadableDatabase();

        Cursor cursor = db.query(TABLE_Name, new String[] { _Id,
                qotes,author }, _Id + "=?", new String[] { String.valueOf(id) },
                null, null, null, null);

        //String query = "SELECT _Id, qotes, author From "+TABLE_Name;
        //String query = "SELECT * From Quotes";

        //Cursor cursor = db.rawQuery(query, null);

        if (cursor != null)
            cursor.moveToFirst();
        Quotes quotes = new Quotes(Integer.parseInt(cursor.getString(0)),
        cursor.getString(1),cursor.getString(2));
        QuoteList.add(quotes);
        return QuoteList;
    }
    */
}

最佳答案

将此权限添加到项目的AndroidManifest.xml文件中的manifest标记(应为顶级标记)中。

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

10-08 13:21