ios - Twitter 趋势 API 1.1 错误 "unrecognized selector sent to instance"

Question

看看下面我的代码:

NSError *jsonParsingError;
NSDictionary *jsonResults = [NSJSONSerialization JSONObjectWithData:responseData options:0 error:&jsonParsingError];
NSArray *trends = jsonResults[@"trends"]; //error on this line

我遇到“无法识别的选择器发送到实例”错误。

我使用的网址是:https://api.twitter.com/1.1/trends/place.json?id=1

查看 jsonResults 值:

与 TwitterSearch(示例应用程序)结果相比:

这是 jsonResults 变量的记录值:

2013-08-26 11:05:44.489 TwitterTrends[48410:490b] JSON: (
        {
        "as_of" = "2013-08-26T03:04:24Z";
        "created_at" = "2013-08-26T02:51:26Z";
        locations =         (
                        {
                name = Worldwide;
                woeid = 1;
            }
        );
        trends =         (
                        {
                events = "<null>";
                name = "#chupaedu";
                "promoted_content" = "<null>";
                query = "%23chupaedu";
                url = "http://twitter.com/search?q=%23chupaedu";
            },
                        {
                events = "<null>";
                name = "#VMA2013NAMTV";
                "promoted_content" = "<null>";
                query = "%23VMA2013NAMTV";
                url = "http://twitter.com/search?q=%23VMA2013NAMTV";
            },
                        {
                events = "<null>";
                name = "#YoConfiesoQue";
                "promoted_content" = "<null>";
                query = "%23YoConfiesoQue";
                url = "http://twitter.com/search?q=%23YoConfiesoQue";
            },
                        {
                events = "<null>";
                name = "#MiObsesionPor";
                "promoted_content" = "<null>";
                query = "%23MiObsesionPor";
                url = "http://twitter.com/search?q=%23MiObsesionPor";
            },
                        {
                events = "<null>";
                name = "#LasMejoresPeliculasQueViFueron";
                "promoted_content" = "<null>";
                query = "%23LasMejoresPeliculasQueViFueron";
                url = "http://twitter.com/search?q=%23LasMejoresPeliculasQueViFueron";
            },
                        {
                events = "<null>";
                name = "Emile Sande";
                "promoted_content" = "<null>";
                query = "%22Emile+Sande%22";
                url = "http://twitter.com/search?q=%22Emile+Sande%22";
            },
                        {
                events = "<null>";
                name = "Daniel Furlan";
                "promoted_content" = "<null>";
                query = "%22Daniel+Furlan%22";
                url = "http://twitter.com/search?q=%22Daniel+Furlan%22";
            },
                        {
                events = "<null>";
                name = JHud;
                "promoted_content" = "<null>";
                query = JHud;
                url = "http://twitter.com/search?q=JHud";
            },
                        {
                events = "<null>";
                name = "Omg Adam Lambert";
                "promoted_content" = "<null>";
                query = "%22Omg+Adam+Lambert%22";
                url = "http://twitter.com/search?q=%22Omg+Adam+Lambert%22";
            },
                        {
                events = "<null>";
                name = "Macklemore & Ryan Lewis";
                "promoted_content" = "<null>";
                query = "%22Macklemore+%26+Ryan+Lewis%22";
                url = "http://twitter.com/search?q=%22Macklemore+%26+Ryan+Lewis%22";
            }
        );
    }
)

Answer 1

如 H2CO3 所示，返回的是一个数组，而不是一个字典。我将代码修改为:

NSArray *jsonResults = [NSJSONSerialization JSONObjectWithData:responseData 选项:0 错误:&jsonParsingError];