Android studio 错误：找不到符号变量MyOpenWeatherMapApiKey Android

我是Android新手。我需要帮助来解决下面的错误。 我被困在这里了

public class ForecastFragment extends Fragment {

    private ArrayAdapter<String> mForecastAdapter;

    public ForecastFragment() {
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Add this line in order for this fragment to handle menu events.
        setHasOptionsMenu(true);
    }

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        inflater.inflate(R.menu.forecastfragment, menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_refresh) {
            FetchWeatherTask weatherTask = new FetchWeatherTask();
            weatherTask.execute("94043");
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        // Create some dummy data for the ListView.  Here's a sample weekly forecast
        String[] data = {
                "Mon 6/23 - Sunny - 31/17",
                "Tue 6/24 - Foggy - 21/8",
                "Wed 6/25 - Cloudy - 22/17",
                "Thurs 6/26 - Rainy - 18/11",
                "Fri 6/27 - Foggy - 21/10",
                "Sat 6/28 - TRAPPED IN WEATHERSTATION - 23/18",
                "Sun 6/29 - Sunny - 20/7"
        };
        List<String> weekForecast = new ArrayList<String>(Arrays.asList(data));

        // Now that we have some dummy forecast data, create an ArrayAdapter.
        // The ArrayAdapter will take data from a source (like our dummy forecast) and
        // use it to populate the ListView it's attached to.
        mForecastAdapter =
                new ArrayAdapter<String>(
                        getActivity(), // The current context (this activity)
                        R.layout.list_item_forecast, // The name of the layout ID.
                        R.id.list_item_forecast_textview, // The ID of the textview to populate.
                        weekForecast);

        View rootView = inflater.inflate(R.layout.fragment_main, container, false);

        // Get a reference to the ListView, and attach this adapter to it.
        ListView listView = (ListView) rootView.findViewById(R.id.listview_forecast);
        listView.setAdapter(mForecastAdapter);

        return rootView;
    }

    public class FetchWeatherTask extends AsyncTask<String, Void, String[]> {

        private final String LOG_TAG = FetchWeatherTask.class.getSimpleName();

        /* The date/time conversion code is going to be moved outside the asynctask later,
         * so for convenience we're breaking it out into its own method now.
         */
        private String getReadableDateString(long time){
            // Because the API returns a unix timestamp (measured in seconds),
            // it must be converted to milliseconds in order to be converted to valid date.
            SimpleDateFormat shortenedDateFormat = new SimpleDateFormat("EEE MMM dd");
            return shortenedDateFormat.format(time);
        }

        /**
         * Prepare the weather high/lows for presentation.
         */
        private String formatHighLows(double high, double low) {
            // For presentation, assume the user doesn't care about tenths of a degree.
            long roundedHigh = Math.round(high);
            long roundedLow = Math.round(low);

            String highLowStr = roundedHigh + "/" + roundedLow;
            return highLowStr;
        }

        /**
         * Take the String representing the complete forecast in JSON Format and
         * pull out the data we need to construct the Strings needed for the wireframes.
         *
         * Fortunately parsing is easy:  constructor takes the JSON string and converts it
         * into an Object hierarchy for us.
         */
        private String[] getWeatherDataFromJson(String forecastJsonStr, int numDays)
                throws JSONException {

            // These are the names of the JSON objects that need to be extracted.
            final String OWM_LIST = "list";
            final String OWM_WEATHER = "weather";
            final String OWM_TEMPERATURE = "temp";
            final String OWM_MAX = "max";
            final String OWM_MIN = "min";
            final String OWM_DESCRIPTION = "main";

            JSONObject forecastJson = new JSONObject(forecastJsonStr);
            JSONArray weatherArray = forecastJson.getJSONArray(OWM_LIST);

            // OWM returns daily forecasts based upon the local time of the city that is being
            // asked for, which means that we need to know the GMT offset to translate this data
            // properly.

            // Since this data is also sent in-order and the first day is always the
            // current day, we're going to take advantage of that to get a nice
            // normalized UTC date for all of our weather.

            Time dayTime = new Time();
            dayTime.setToNow();

            // we start at the day returned by local time. Otherwise this is a mess.
            int julianStartDay = Time.getJulianDay(System.currentTimeMillis(), dayTime.gmtoff);

            // now we work exclusively in UTC
            dayTime = new Time();

            String[] resultStrs = new String[numDays];
            for(int i = 0; i < weatherArray.length(); i++) {
                // For now, using the format "Day, description, hi/low"
                String day;
                String description;
                String highAndLow;

                // Get the JSON object representing the day
                JSONObject dayForecast = weatherArray.getJSONObject(i);

                // The date/time is returned as a long.  We need to convert that
                // into something human-readable, since most people won't read "1400356800" as
                // "this saturday".
                long dateTime;
                // Cheating to convert this to UTC time, which is what we want anyhow
                dateTime = dayTime.setJulianDay(julianStartDay+i);
                day = getReadableDateString(dateTime);

                // description is in a child array called "weather", which is 1 element long.
                JSONObject weatherObject = dayForecast.getJSONArray(OWM_WEATHER).getJSONObject(0);
                description = weatherObject.getString(OWM_DESCRIPTION);

                // Temperatures are in a child object called "temp".  Try not to name variables
                // "temp" when working with temperature.  It confuses everybody.
                JSONObject temperatureObject = dayForecast.getJSONObject(OWM_TEMPERATURE);
                double high = temperatureObject.getDouble(OWM_MAX);
                double low = temperatureObject.getDouble(OWM_MIN);

                highAndLow = formatHighLows(high, low);
                resultStrs[i] = day + " - " + description + " - " + highAndLow;
            }

            for (String s : resultStrs) {
                Log.v(LOG_TAG, "Forecast entry: " + s);
            }
            return resultStrs;

        }
        @Override
        protected String[] doInBackground(String... params) {

            // If there's no zip code, there's nothing to look up.  Verify size of params.
            if (params.length == 0) {
                return null;
            }

            // These two need to be declared outside the try/catch
            // so that they can be closed in the finally block.
            HttpURLConnection urlConnection = null;
            BufferedReader reader = null;

            // Will contain the raw JSON response as a string.
            String forecastJsonStr = null;

            String format = "json";
            String units = "metric";
            int numDays = 7;

            try {
                // Construct the URL for the OpenWeatherMap query
                // Possible parameters are avaiable at OWM's forecast API page, at
                // http://openweathermap.org/API#forecast
                final String FORECAST_BASE_URL =
                        "http://api.openweathermap.org/data/2.5/forecast/daily?";
                final String QUERY_PARAM = "q";
                final String FORMAT_PARAM = "mode";
                final String UNITS_PARAM = "units";
                final String DAYS_PARAM = "cnt";
                final String APPID_PARAM = "02867cfd75153da1eda43a17f213ffc5";


                Uri builtUri = Uri.parse(FORECAST_BASE_URL).buildUpon()
                        .appendQueryParameter(QUERY_PARAM, params[0])
                        .appendQueryParameter(FORMAT_PARAM, format)
                        .appendQueryParameter(UNITS_PARAM, units)
                        .appendQueryParameter(DAYS_PARAM, Integer.toString(numDays))
                        .appendQueryParameter(APPID_PARAM, BuildConfig.OPEN_WEATHER_MAP_API_KEY)

                        .build();

                URL url = new URL(builtUri.toString());

                Log.v(LOG_TAG, "Built URI " + builtUri.toString());

                // Create the request to OpenWeatherMap, and open the connection
                urlConnection = (HttpURLConnection) url.openConnection();
                urlConnection.setRequestMethod("GET");
                urlConnection.connect();

                // Read the input stream into a String
                InputStream inputStream = urlConnection.getInputStream();
                StringBuffer buffer = new StringBuffer();
                if (inputStream == null) {
                    // Nothing to do.
                    return null;
                }
                reader = new BufferedReader(new InputStreamReader(inputStream));

                String line;
                while ((line = reader.readLine()) != null) {
                    // Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
                    // But it does make debugging a *lot* easier if you print out the completed
                    // buffer for debugging.
                    buffer.append(line + "\n");
                }

                if (buffer.length() == 0) {
                    // Stream was empty.  No point in parsing.
                    return null;
                }
                forecastJsonStr = buffer.toString();

                Log.v(LOG_TAG, "Forecast string: " + forecastJsonStr);
            } catch (IOException e) {
                Log.e(LOG_TAG, "Error ", e);
                // If the code didn't successfully get the weather data, there's no point in attemping
                // to parse it.
                return null;
            } finally {
                if (urlConnection != null) {
                    urlConnection.disconnect();
                }
                if (reader != null) {
                    try {
                        reader.close();
                    } catch (final IOException e) {
                        Log.e(LOG_TAG, "Error closing stream", e);
                    }
                }
            }

            try {
                return getWeatherDataFromJson(forecastJsonStr, numDays);
            } catch (JSONException e) {
                Log.e(LOG_TAG, e.getMessage(), e);
                e.printStackTrace();
            }

            // This will only happen if there was an error getting or parsing the forecast.
            return null;
        }


            }
        }
    }
}

[{
public final class BuildConfig {
  public static final boolean DEBUG = Boolean.parseBoolean("true");
  public static final String APPLICATION_ID = "com.example.patels.sunshine";
  public static final String BUILD_TYPE = "debug";
  public static final String FLAVOR = "";
  public static final int VERSION_CODE = 1;
  public static final String VERSION_NAME = "1.0";
  // Fields from build type: debug
  public static final String OPEN_WEATHER_MAP_API_KEY = MyOpenWeatherMapApiKey;
}

公共类ForecastFragment扩展了片段{
专用阵列适配器mForecastAdapter；
公众预报员（）{
}
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
//添加此行，以便此片段处理菜单事件。
设置选项菜单（真）；
}
@凌驾
创建选项菜单（菜单菜单，菜单充气机）{
充气机。充气（右菜单。艏楼碎片，菜单）；
}
@凌驾
公共布尔值onOptionsItemSelected（菜单项项）{
//处理操作栏项目单击此处。操作栏将
//自动处理Home/Up按钮上的点击，只要
//在AndroidManifest.xml中指定父活动时。
int id=item.getItemId（）；
if（id==R.id.action\u刷新）{
FetchWeatherTask weatherTask=新的FetchWeatherTask（）；
weatherTask.execute（“94043”）；
返回true；
}
返回super.onOptionsItemSelected（项目）；
}
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、，
Bundle savedInstanceState）{
//为ListView创建一些虚拟数据
字符串[]数据={
“周一6/23 - 阳光明媚-2017年11月31日“，
“6月24日星期二-大雾-21月8日”，
“6月25日星期三-多云-17月22日”，
“6月26日星期四-雨季-11月18日”，
“6月27日星期五-大雾-10月21日”，
“Sat 6/28-被困在气象站-23/18”，
“太阳6/29-晴朗-20/7”
};
List-weekForecast=newarraylist（Arrays.asList（data））；
//现在我们有了一些虚拟预测数据，创建一个ArrayAdapter。
//ArrayAdapter将从源（如我们的虚拟预测）获取数据，然后
//使用它填充它附加到的ListView。
mForecastAdapter=
新阵列适配器(
getActivity（），//当前上下文（此活动）
R.layout.list\u item\u forecast，//布局ID的名称。
R.id.list\u item\u forecast\u textview，//要填充的textview的id。
周预测）；
视图根视图=充气机。充气（R.layout.fragment_main，容器，错误）；
//获取对ListView的引用，并将此适配器连接到它。
ListView ListView=（ListView）rootView.findViewById（R.id.ListView\u forecast）；
setAdapter（mForecastAdapter）；
返回rootView；
}
公共类FetchWeatherTask扩展了AsyncTask{
私有最终字符串LOG_TAG=FetchWeatherTask.class.getSimpleName（）；
/*日期/时间转换代码稍后将被移到asynctask之外，
*为了方便起见，我们现在将其分解为自己的方法。
*/
私有字符串getReadableDateString（长时间）{
//因为API返回unix时间戳（以秒为单位），
//必须将其转换为毫秒才能转换为有效日期。
SimpleDateFormat shortenedDateFormat=新的SimpleDateFormat（“EEE MMM dd”）；
返回shortenedDateFormat.format（时间）；
}
/**
*为演示做好天气高/低的准备。
*/
专用字符串格式HighLows（双高、双低）{
//对于演示，假设用户不关心十分之一的学位。
长轮高=数学轮（高）；
长轮低=数学轮（低）；
字符串highLowStr=roundedHigh+“/”+roundedLow；
返回highLowStr；
}
/**
*以JSON格式获取表示完整预测的字符串，然后
*取出我们需要的数据来构造线框所需的字符串。
*
*幸运的是，解析很容易：构造函数获取JSON字符串并转换它
*为我们创建一个对象层次结构。
*/
私有字符串[]getWeatherDataFromJson（字符串forecastJsonStr，int numDays）
抛出JSONException{
//这些是需要提取的JSON对象的名称。
最终字符串OWM_LIST=“LIST”；
最终字符串OWM_WEATHER=“WEATHER”；
最终字符串OWM_TEMPERATURE=“temp”；
最终字符串OWM_MAX=“MAX”；
最终字符串OWM_MIN=“MIN”；
最终字符串OWM_DESCRIPTION=“main”；
JSONObject forecastJson=新的JSONObject（forecastJsonStr）；
JSONArray weatherArray=forecastJson.getJSONArray（OWM_列表）；
//OWM将根据所选城市的当地时间返回每日预测
//这意味着我们需要知道GMT偏移量来转换这些数据
//对。
//因为此数据也是按顺序发送的，并且第一天始终是
//今天，我们将利用这一点来获得一个好的
//我们所有天气的标准化UTC日期。
白天时间=新时间（）；
白天；
//我们从当地时间返回的那一天开始。否则这就是一片混乱。
int julianStartDay=Time.getJulianDay（System.currentTimeMillis（），day.gmtoff）；
//现在我们只在UTC工作
白天=新时间（）；
String[]resultStrs=新字符串[numDays]；
对于（int i=0；iit.buildConfigField "String" , "OPEN_WEATHER_MAP_API_KEY" ,  "\"MyOpenWeatherMapApiKey\""

public static final String OPEN_WEATHER_MAP_API_KEY = MyOpenWeatherMapApiKey;