java - 在Android异常中插入SQLite

Question

我创建了一个简单的 Android 应用程序来处理 SQLite 数据库，以便从表中插入和检索数据，但是当我尝试插入数据或检索时，会发生如下所示的异常:

01-26 15:48:30.930: E/AndroidRuntime(25783): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.androidhive.loginandregister/com.androidhive.loginandregister.LoginActivity}: android.database.sqlite.SQLiteException: near ")": syntax error (code 1): , while compiling: INSERT INTO info() VALUES (?)

下面是我的代码:

LoginActivity.java

package com.androidhive.loginandregister;

import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class LoginActivity extends Activity {
    DataHandler data;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        data= new DataHandler(getBaseContext());
        data.open();
        long x = data.insertdata("a", "b", "c", "d", "e");

        Toast.makeText(getBaseContext(),"Insertion Completed", Toast.LENGTH_LONG).show();

        data.close();

        Button btn = (Button)findViewById(R.id.btnLogin);

        btn.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {

                data = new DataHandler(getBaseContext());
                data.open();
                Cursor c = data.returndata();
                if(c.moveToFirst())
                {
                    do
                    {
                        Toast.makeText(getBaseContext(),c.getString(0)+ " "+ c.getString(1)+" "+c.getString(2) ,Toast.LENGTH_LONG).show();
                    }while(c.moveToNext());


                    }
                data.close();
                }

                });

    }
}

DataHandler.java

package com.androidhive.loginandregister;

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

public class DataHandler {

    public static final String id ="";
    public static final String name ="";
    public static final String number ="";
    public static final String email ="";
    public static final String website ="";
    public static final String table_name ="info";
    public static final String data_base_name ="bcb";
    public static final int database_version = 1;
    public static final String table_create ="CREATE TABLE info(id TEXT,name TEXT,number TEXT,email TEXT,website TEXT);";

    databasehelper dbhelper;
    Context ctx;
    SQLiteDatabase db;


    public DataHandler (Context ctx)
    {
        this.ctx=ctx;
        dbhelper = new databasehelper(ctx);
    }

    private static class databasehelper extends SQLiteOpenHelper
    {

    public databasehelper(Context ctx)
    {
        super(ctx,data_base_name,null,database_version);
    }

        @Override
        public void onCreate(SQLiteDatabase db) {

            try
            {
                db.execSQL(table_create);
            }

            catch (SQLException e)
            {
                e.printStackTrace();
            }

        }




        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

            db.execSQL("DROP TABLE IF EXISTS info");
            onCreate(db);
        }

    }


    public DataHandler open()
    {
    db = dbhelper.getWritableDatabase();
    return this;
    }

    public void close()
    {
        dbhelper.close();

    }

    public long insertdata(String ID, String NAME,String NUMBER,String EMAIL,String WEBSITE,String COMPANY,String PROFESSION,String COMMENTS,String STATUS)
    {
        ContentValues content = new ContentValues();
        content.put(id, ID);
        content.put(name, NAME);
        content.put(number,NUMBER);
        content.put(email, EMAIL);
        content.put(website, WEBSITE);
        return db.insertOrThrow(table_name, null, content);


    }

    public Cursor returndata()
    {
        return db.query(table_name, new String [] {id,name,number,email,website}, null, null, null, null, null);
    }
}

感谢您的帮助。

Answer 1

我认为这些应该包含您的列名称

public static final String id ="";
public static final String name ="";
public static final String number ="";
public static final String email ="";
public static final String website ="";

这就是为什么您在插入查询中得到空列列表的原因。用适当的值填充它们。