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Database Flex 4.5.1-移动模拟器上的数据库访问问题_Database_Sqlite_Mobile_Flex4.5 - Fatal编程技术网

Database Flex 4.5.1-移动模拟器上的数据库访问问题

Database Flex 4.5.1-移动模拟器上的数据库访问问题,database,sqlite,mobile,flex4.5,Database,Sqlite,Mobile,Flex4.5,我正在尝试连接到位于项目资产文件夹中的SQLite数据库。 我写了一个类,下面是抛出错误的部分: public class Database { private var sqlConnection:SQLConnection; public function connect(db:String):Object { var response:Object={status:false,message:''}; try {

我正在尝试连接到位于项目资产文件夹中的SQLite数据库。 我写了一个类,下面是抛出错误的部分:

public class Database
{
    private var sqlConnection:SQLConnection;

    public function connect(db:String):Object
    {
        var response:Object={status:false,message:''};
        try
        {
            var dbFile:File=File.applicationDirectory.resolvePath(db);
            sqlConnection.open(dbFile);
            response.status=true;
            response.message='';
        }
        catch(error:SQLError)
        {
            response.status=false
            response.message=error.message;
        }
        return response;
    }
}
我在
creationComplete
处理程序的MXML视图组件中调用该类:

private function init():void
{
    var db:Database=new Database();
    var connectResponse:Object=db.connect('assets/data.db');
    if(connectResponse.status)
    {
        //getData() runs a simple select query and returns an array
        acData=new ArrayCollection(db.getData());
    }
    else
    {
        //If the status is false I show a label control for debugging
        labelError.text=connectResponse.message;
        labelError.includeInLayout=true;
        labelError.visible=true;
    }

    list.dataProvider=acData;
}

我得到的错误大致如下:
TypeError:error#1009:无法访问空对象引用的属性或方法。

我认为在使用sqlConnection之前需要实例化它:

sqlConnection = new SQLConnection();
sqlConnection.open(dbFile);

哪一行抛出了TypeError?第22行,即
sqlConnection.open(dbFile)。哈哈,我真不敢相信我错过了。我已经想了差不多两天了。。。谢谢你,6。