问题描述

局部变量初始化的问题

public class DatabaseHandler extends SQLiteOpenHelper {// All Static variables// Database Versionprivate static final int DATABASE_VERSION = 1;// Database Nameprivate static final String DATABASE_NAME = ""contextsManager"";// Locations table nameprivate static final String TABLE_LOCATIONLABLES = ""locationLables"";// LOCATIONLABLES Table Columns namesprivate static final String KEY_LOCID = ""loc_id"";private static final String KEY_LOCNAME = ""loc_name"";public DatabaseHandler(Context context) {    super(context DATABASE_NAME null DATABASE_VERSION);}// Creating Tables@Overridepublic void onCreate(SQLiteDatabase db) {    String TABLE_LOCATIONLABLES = ""CREATE TABLE "" + TABLE_LOCATIONLABLES + ""(""            + KEY_LOCID + "" INTEGER PRIMARY KEY + KEY_LOCNAME + "" TEXT            +  "")"";    db.execSQL(TABLE_LOCATIONLABLES);   }

提示说的是局部变量TABLE_LOCATIONLABLES可能没有被初始化?可是我初始化了的呀，这个错误如何发生的呢?

解决方案

String TABLE_LOCATIONLABLES = ""CREATE TABLE "" + TABLE_LOCATIONLABLES + ""(""

等号两各有一个，而且String TABLE_LOCATIONLABLES这个还是新定义的，计算机迷糊了，它不认为你上面已经定义了

解决方案二：
在 oncreate(db) 里重命名 字符串 TABLE_LOCATIONLABLES

@Override    public void onCreate(SQLiteDatabase db) {        String mQuery = ""CREATE TABLE "" + TABLE_LOCATIONLABLES + ""(""                + KEY_LOCID + "" INTEGER PRIMARY KEY + KEY_LOCNAME + "" TEXT                +  "")"";        db.execSQL(mQuery);       }