如何使用 api 获取数据，我使用的是 api.weathermap.org ；但我只能获取一些数据

Question

这是我要从中获取数据的整个字符串（这基本上是伦敦的天气详细信息）

{
  "coord": {
    "lon": -0.13,
    "lat": 51.51
  },
  "weather": [
    {
      "id": 721,
      "main": "Haze",
      "description": "haze",
      "icon": "50d"
    },
    {
      "id": 701,
      "main": "Mist",
      "description": "mist",
      "icon": "50d"
    }
  ],
  "base": "stations",
  "main": {
    "temp": 278.15,
    "pressure": 1010,
    "humidity": 81,
    "temp_min": 276.15,
    "temp_max": 279.15
  },
  "visibility": 6000,
  "wind": {
    "speed": 4.1,
    "deg": 110
  },
  "clouds": {
    "all": 40
  },
  "dt": 1485525000,
  "sys": {
    "type": 1,
    "id": 5091,
    "message": 0.048,
    "country": "GB",
    "sunrise": 1485503103,
    "sunset": 1485535344
  },
  "id": 2643743,
  "name": "London",
  "cod": 200
}

我在我的 android 代码中使用过这个

protected void onPostExecute(String result)
{
    super.onPostExecute(result);

    try {
        String message = "";

        JSONObject jsonObject = new JSONObject(result);

        String weatherInfo = jsonObject.getString("weather");

        Log.i("Weather content", weatherInfo);

        JSONArray arr = new JSONArray(weatherInfo);

        for (int i = 0; i < arr.length(); i++) {
            JSONObject jsonPart = arr.getJSONObject(i);

            String main = "";
            String description = "";

            main = jsonPart.getString("main");
            description = jsonPart.getString("description");

            if (main != "" && description != "") {
                message += main + ": " + description + "\r\n";
            }
        }

        if (message != "") {
            resultTextView.setText(message);
        } else {
            Toast.makeText(getApplicationContext(), "Could not find weather", Toast.LENGTH_LONG).show();
        }
    } catch (JSONException e) {
        Toast.makeText(getApplicationContext(), "Could not find weather", Toast.LENGTH_LONG).show();
    }
}

使用上面的代码，我可以从“天气”数组中获取主要和描述等数据，但我无法从“sys”数组中获取数据（对于日落、日出值和国家/地区）

Answer 1

“sys”不是数组，可以从代码中的根json对象“jsonObject”访问。

JSONObject sysJson = jsonObject.getJSONObject("sys");
String strSunrise = sysJson.getString("sunrise");