小编vig*_*ere的帖子

我有以下代码,第一个游标对象工作正常,但当我做另一个查询并将其分配给flightCursor时,它给出了错误.

Cursor cursor = database.query( CityAndAirportsTable.notificationsTable, new String[] { CityAndAirportsTable.notifyFlightId },
                null, null, null, null, "Id DESC" );
        cursor.moveToFirst();
        while( !cursor.isAfterLast() ){
            String id = String.valueOf( cursor.getInt( 0 ) );
            Cursor flightCursor = database.query( CityAndAirportsTable.flightTable, new String[] { CityAndAirportsTable.fromDestinationCode,
            CityAndAirportsTable.toDestinationCode, CityAndAirportsTable.currentPrice }, CityAndAirportsTable.flightId + "=" + id,
                    null, null, null, null );
}

这里的flightCursor = database.query,我得到错误.

日志

03-27 23:49:09.628: E/SQLiteLog(2296): (14) cannot open file at line 30046 of [9491ba7d73]
03-27 23:49:09.628: E/SQLiteLog(2296): (14) os_unix.c:30046: (24) open(/data/data/com.flightapp.myapp/databases/Application_DB-journal) - 
03-27 23:49:09.628: E/SQLiteLog(2296): …

为了将shared_ptr分配给柠檬图库中的Graph类型变量,我这样做了:

typedef ListDigraph Graph;
typedef std::shared_ptr<Graph> Process_pointer;
Process_pointer process(new Graph);

它运行正常,但现在我需要为地图对象声明一个shared_ptr,通常地图对象的工作方式如下:

Graph process;
typedef ListDigraph::NodeMap<string> Node_names;
Node_names name(process);

也就是说,name需要Graph对象作为其默认构造函数.

为了声明一个shared_ptr,我这样做了:

typedef ListDigraph::NodeMap<string> Node_names;
typedef std::shared_ptr<Node_names> Nname_pointer;
Nname_pointer name = new Node_names;
name(process);

我知道,名称的声明是错误的,但我如何分配内存以及用进程对象初始化它.