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我试图在创建表时在 SQLite 数据库中添加值，但代码意外停止。我试图通过在日志中输入命令来检查它在哪里弯腰。两个表都成功创建。当我们尝试在 onCreate() 方法中插入值时，就会出现问题。任何建议，有什么问题？

package moin.WPG.databasecheck;


import java.util.ArrayList;
import java.util.List;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

public class DatabaseHandler extends SQLiteOpenHelper {

    // All Static variables
    // Database Version
    private static final int DATABASE_VERSION = 1;

    // Database Name
    private static final String DATABASE_NAME = "applicationManager";
    // Contacts table name
    private static final String TABLE_EMERGENCY_CONTACTS = "emerencyContacts";
    private static final String TABLE_PERSONAL_CONTACTS = "personalContacts";

    // Contacts Table Columns names
    private static final String KEY_ID = "id";
    private static final String KEY_NAME = "name";
    private static final String KEY_PH_NO = "phone_number";
    private static final String KEY_EMAIL_ID = "email_id";

    private static final String KEY_USER_ID = "userId";
    private static final String KEY_APP_PASSWORD = "app_password";
    private static final String KEY_USER_NAME = "user_name";

    public DatabaseHandler(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    // Creating Tables
    @Override
    public void onCreate(SQLiteDatabase db) {

        String CREATE_EMERGENCY_CONTACTS_TABLE = "CREATE TABLE " + TABLE_EMERGENCY_CONTACTS + "("
                + KEY_ID + " INTEGER PRIMARY KEY," + KEY_NAME + " TEXT,"
                + KEY_PH_NO + " TEXT," + KEY_EMAIL_ID + " TEXT" + ")";
        db.execSQL(CREATE_EMERGENCY_CONTACTS_TABLE);
        Log.d("table","table created 1");

        String CREATE_PERSONAL_CONTACTS_TABLE = "CREATE TABLE " + TABLE_PERSONAL_CONTACTS + "("
                + KEY_USER_ID + " INTEGER PRIMARY KEY," + KEY_USER_NAME + " TEXT,"
                + KEY_APP_PASSWORD + " TEXT" + ")";
        db.execSQL(CREATE_PERSONAL_CONTACTS_TABLE);
        Log.d("table","table created 2");

        db = this.getWritableDatabase();

        ContentValues[] values = new ContentValues[3];
        for(int i=1;i<=3;i++){
        values[i-1].put(KEY_ID, i);
        values[i-1].put(KEY_NAME, "name"+i); // Contact Name
        values[i-1].put(KEY_PH_NO, "ph"+1);// Contact Phone
        values[i-1].put(KEY_EMAIL_ID, "id"+i);
        db.insert(TABLE_EMERGENCY_CONTACTS, null, values[i-1]);

        }
        Log.d("inserted","table 1");
        ContentValues values2 = new ContentValues();
        values2.put(KEY_USER_ID, 1);
        values2.put(KEY_USER_NAME, "username");
        values2.put(KEY_APP_PASSWORD, "password");
        db.insert(TABLE_PERSONAL_CONTACTS, null, values2);
        Log.d("inserted","table 2"); */
        db.close(); // Closing database connection

        Log.d("database","closing");
    }

    // Upgrading database
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // Drop older table if existed
        db.execSQL("DROP TABLE IF EXISTS ");

        // Create tables again
        onCreate(db);
    }

    /**
     * All CRUD(Create, Read, Update, Delete) Operations
     */

    // Adding new contact
   /*  void addContact(Contact contact) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_ID, contact.getID());
        values.put(KEY_NAME, contact.getName()); // Contact Name
        values.put(KEY_PH_NO, contact.getPhoneNumber());// Contact Phone
        values.put(KEY_EMAIL_ID, contact.getEmailId());

        // Inserting Row
        db.insert(TABLE_EMERGENCY_CONTACTS, null, values);
        db.close(); // Closing database connection
    } */

    // Getting single contact
    Contact getEmergencyContact(int id) {
        SQLiteDatabase db = this.getReadableDatabase();

        Cursor cursor = db.query(TABLE_EMERGENCY_CONTACTS, new String[] { KEY_ID,
                KEY_NAME, KEY_PH_NO, KEY_EMAIL_ID }, KEY_ID + "=?",
                new String[] { String.valueOf(id) }, null, null, null, null);
        if (cursor != null)
            cursor.moveToFirst();

        Contact contact = new Contact(Integer.parseInt(cursor.getString(0)),
                cursor.getString(1), cursor.getString(2),cursor.getString(3));
        // return contact
        return contact;
    }

    UserInfo getUserInfo(int id) {
        SQLiteDatabase db = this.getReadableDatabase();

        Cursor cursor = db.query(TABLE_PERSONAL_CONTACTS, new String[] { KEY_USER_ID,
                KEY_USER_NAME, KEY_APP_PASSWORD }, KEY_USER_ID + "=?",
                new String[] { String.valueOf(id) }, null, null, null, null);
        if (cursor != null)
            cursor.moveToFirst();

        UserInfo userInfo = new UserInfo(Integer.parseInt(cursor.getString(0)),
                cursor.getString(1), cursor.getString(2));
        // return contact
        return userInfo;
    }
    // Getting All Contacts
   /* public List<Contact> getAllContacts() {
        List<Contact> contactList = new ArrayList<Contact>();
        // Select All Query
        String selectQuery = "SELECT  * FROM " + TABLE_EMERGENCY_CONTACTS;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery, null);

        // looping through all rows and adding to list
        if (cursor.moveToFirst()) {
            do {
                Contact contact = new Contact();
                contact.setID(Integer.parseInt(cursor.getString(0)));
                contact.setName(cursor.getString(1));
                contact.setPhoneNumber(cursor.getString(2));
                contact.setEmailId(cursor.getString(2));
                // Adding contact to list
                contactList.add(contact);
            } while (cursor.moveToNext());
        }

        // return contact list
        return contactList;
    } */ 

    // Updating single contact
    public int updateEmergencyContact(Contact contact) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_ID, contact.getID());
        values.put(KEY_NAME, contact.getName());
        values.put(KEY_PH_NO, contact.getPhoneNumber());
        values.put(KEY_EMAIL_ID, contact.getEmailId());

        // updating row
        return db.update(TABLE_EMERGENCY_CONTACTS, values, KEY_ID + " = ?",
                new String[] { String.valueOf(contact.getID()) });
    }

    public int updateUserInfo(UserInfo userInfo) {
        SQLiteDatabase db = this.getWritableDatabase();

        ContentValues values = new ContentValues();
        values.put(KEY_USER_ID, userInfo.getID());
        values.put(KEY_USER_NAME, userInfo.getName());
        values.put(KEY_APP_PASSWORD, userInfo.getPassword());

        // updating row
        return db.update(TABLE_PERSONAL_CONTACTS, values, KEY_ID + " = ?",
                new String[] { String.valueOf(userInfo.getID()) });
    }
    // Deleting single contact
 /*   public void deleteContact(Contact contact) {
        SQLiteDatabase db = this.getWritableDatabase();
        db.delete(TABLE_EMERGENCY_CONTACTS, KEY_ID + " = ?",
                new String[] { String.valueOf(contact.getID()) });
        db.close();
    } */

    // Getting contacts Count
   /* public int getContactsCount() {
        String countQuery = "SELECT  * FROM " + TABLE_EMERGENCY_CONTACTS;
        SQLiteDatabase db = this.getReadableDatabase();
        Cursor cursor = db.rawQuery(countQuery, null);
        cursor.close();

        // return count
        return cursor.getCount();
    } */

}

这是错误日志：

      4-13 12:20:08.727: D/table(754): table created 1
    04-13 12:20:08.747: D/table(754): table created 2
    04-13 12:20:08.757: D/AndroidRuntime(754): Shutting down VM
    04-13 12:20:08.766: W/dalvikvm(754): threadid=1: thread exiting with                          uncaught exception (group=0x409961f8)
    04-13 12:20:08.787: E/AndroidRuntime(754): FATAL EXCEPTION: main
    04-13 12:20:08.787: E/AndroidRuntime(754): java.lang.RuntimeException: Unable to start activity ComponentInfo{moin.WPG.databasecheck/moin.WPG.databasecheck.WPGDBActivity}: java.lang.IllegalStateException: getWritableDatabase called recursively
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1955)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1980)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.ActivityThread.access$600(ActivityThread.java:122)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1146)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.os.Handler.dispatchMessage(Handler.java:99)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.os.Looper.loop(Looper.java:137)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.ActivityThread.main(ActivityThread.java:4340)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at java.lang.reflect.Method.invokeNative(Native Method)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at java.lang.reflect.Method.invoke(Method.java:511)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at dalvik.system.NativeStart.main(Native Method)
    04-13 12:20:08.787: E/AndroidRuntime(754): Caused by: java.lang.IllegalStateException: getWritableDatabase called recursively
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:140)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at moin.WPG.databasecheck.DatabaseHandler.onCreate(DatabaseHandler.java:57)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:165)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.database.sqlite.SQLiteOpenHelper.getReadableDatabase(SQLiteOpenHelper.java:231)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at moin.WPG.databasecheck.DatabaseHandler.getEmergencyContact(DatabaseHandler.java:122)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at moin.WPG.databasecheck.WPGDBActivity.onCreate(WPGDBActivity.java:46)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.Activity.performCreate(Activity.java:4465)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
    04-13 12:20:08.787: E/AndroidRuntime(754):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1919)
    04-13 12:20:08.787: E/AndroidRuntime(754):  ... 11 more
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1 回答 1

2

不要像那些方法调用的那样调用getWritableDatabase()orgetReadableDatabase()的方法，你会让自己陷入循环（并且陷入困境）。SQLiteOpenHelperonCreate

如果您需要数据库引用，请使用该SQLiteDatabase参数，因为它是新数据库：

@Override
public void onCreate(SQLiteDatabase db) {
    //...
    // when you need the database refercence just use db
    // DON'T call getWritableDatabase() and assign it to db
于 2013-04-13T07:32:04.213 回答