app/src/main/java/uk/me/njae/sunshine/ForecastFragment.java

   1 package uk.me.njae.sunshine;
   2
   3 import android.net.Uri;
   4 import android.os.AsyncTask;
   5 import android.os.Bundle;
   6 import android.support.v4.app.Fragment;
   7 import android.util.Log;
   8 import android.view.LayoutInflater;
   9 import android.view.Menu;
  10 import android.view.MenuInflater;
  11 import android.view.MenuItem;
  12 import android.view.View;
  13 import android.view.ViewGroup;
  14 import android.widget.ArrayAdapter;
  15 import android.widget.ListView;
  16
  17 import org.json.JSONArray;
  18 import org.json.JSONException;
  19 import org.json.JSONObject;
  20
  21 import java.io.BufferedReader;
  22 import java.io.IOException;
  23 import java.io.InputStream;
  24 import java.io.InputStreamReader;
  25 import java.net.HttpURLConnection;
  26 import java.net.URL;
  27 import java.text.SimpleDateFormat;
  28 import java.util.ArrayList;
  29 import java.util.Arrays;
  30 import java.util.Date;
  31 import java.util.List;
  32
  33 /**
  34  * A placeholder fragment containing a simple view.
  35  */
  36 public class ForecastFragment extends Fragment {
  37
  38     private ArrayAdapter<String> mForecastAdapter;
  39
  40     public ForecastFragment() {
  41     }
  42
  43     @Override
  44     public void onCreate(Bundle savedInstanceState) {
  45         super.onCreate(savedInstanceState);
  46         setHasOptionsMenu(true);
  47     }
  48
  49     @Override
  50     public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
  51         // Inflate the menu; this adds items to the action bar if it is present.
  52         inflater.inflate(R.menu.forecastfragment, menu);
  53     }
  54
  55     @Override
  56     public boolean onOptionsItemSelected(MenuItem item) {
  57         // Handle action bar item clicks here. The action bar will
  58         // automatically handle clicks on the Home/Up button, so long
  59         // as you specify a parent activity in AndroidManifest.xml.
  60         int id = item.getItemId();
  61         if (id == R.id.action_refresh) {
  62             FetchWeatherTask weatherTask = new FetchWeatherTask();
  63             weatherTask.execute("94043");
  64             return true;
  65         }
  66         return super.onOptionsItemSelected(item);
  67     }
  68
  69     @Override
  70     public View onCreateView(LayoutInflater inflater, ViewGroup container,
  71                              Bundle savedInstanceState) {
  72
  73         String[] forecastArray = {
  74                 "Today - Sunny - 10/10",
  75                 "Tomorrow - Cloudy - 11/11",
  76                 "Tuesday - Snow - 12/12",
  77                 "Wednesday - Rain - 13/13",
  78                 "Thursday - Hail - 14/14",
  79                 "Friday - Scorchio - 15/15",
  80                 "Saturday - Fog - 16/16"
  81         };
  82
  83         List<String> weekForecast = new ArrayList<String>(
  84                 Arrays.asList(forecastArray));
  85         mForecastAdapter = new ArrayAdapter<String>(
  86                 getActivity(),
  87                 R.layout.list_item_forecast,
  88                 R.id.list_item_forecast_textview,
  89                 weekForecast
  90         );
  91
  92         View rootView = inflater.inflate(R.layout.fragment_main, container, false);
  93
  94         ListView list_view = (ListView) rootView.findViewById(R.id.listview_forecast);
  95         list_view.setAdapter(mForecastAdapter);
  96
  97         return rootView;
  98     }
  99
 100     public class FetchWeatherTask extends AsyncTask<String, Void, String[]> {
 101
 102         private final String LOG_TAG = FetchWeatherTask.class.getSimpleName();
 103
 104         @Override
 105         protected void onPostExecute(String[] result) {
 106             if (result != null) {
 107                 mForecastAdapter.clear();
 108 //                for (String dayForecastStr: result) {
 109 //                    mForecastAdapter.add(dayForecastStr);
 110 //                }
 111                 mForecastAdapter.addAll(result);
 112             }
 113         }
 114
 115         @Override
 116         protected String[] doInBackground(String... params) {
 117             if (params.length == 0) {
 118                 return null;
 119             }
 120
 121             // These two need to be declared outside the try/catch
 122             // so that they can be closed in the finally block.
 123             HttpURLConnection urlConnection = null;
 124             BufferedReader reader = null;
 125
 126             // Will contain the raw JSON response as a string.
 127             String forecastJsonStr;
 128
 129             String format = "json";
 130             String units = "metric";
 131             int numDays = 7;
 132
 133             try {
 134                 // Construct the URL for the OpenWeatherMap query
 135                 // Possible parameters are avaiable at OWM's forecast API page, at
 136                 // http://openweathermap.org/API#forecast
 137                 final String FORECAST_BASE_URL = "http://api.openweathermap.org/data/2.5/forecast/daily?";
 138                 final String QUERY_PARAM = "q";
 139                 final String FORMAT_PARAM = "mode";
 140                 final String UNITS_PARAM = "units";
 141                 final String DAYS_PARAM = "cnt";
 142
 143                 Uri builtUri = Uri.parse(FORECAST_BASE_URL).buildUpon()
 144                         .appendQueryParameter(QUERY_PARAM, params[0])
 145                         .appendQueryParameter(FORMAT_PARAM, format)
 146                         .appendQueryParameter(UNITS_PARAM, units)
 147                         .appendQueryParameter(DAYS_PARAM, Integer.toString(numDays))
 148                         .build();
 149
 150                 URL url = new URL(builtUri.toString());
 151 /**/                Log.v(LOG_TAG, "Built URI " + builtUri.toString());
 152
 153                 // Create the request to OpenWeatherMap, and open the connection
 154                 urlConnection = (HttpURLConnection) url.openConnection();
 155                 urlConnection.setRequestMethod("GET");
 156                 urlConnection.connect();
 157
 158                 // Read the input stream into a String
 159                 InputStream inputStream = urlConnection.getInputStream();
 160                 StringBuffer buffer = new StringBuffer();
 161                 if (inputStream == null) {
 162                     // Nothing to do.
 163                     return null;
 164                 }
 165                 reader = new BufferedReader(new InputStreamReader(inputStream));
 166
 167                 String line;
 168                 while ((line = reader.readLine()) != null) {
 169                     // Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
 170                     // But it does make debugging a *lot* easier if you print out the completed
 171                     // buffer for debugging.
 172                     buffer.append(line + "\n");
 173                 }
 174
 175                 if (buffer.length() == 0) {
 176                     // Stream was empty.  No point in parsing.
 177                     return null;
 178                 }
 179                 forecastJsonStr = buffer.toString();
 180 //                Log.v(LOG_TAG, "Forecast JSON string: " + forecastJsonStr);
 181                 try {
 182                     return getWeatherDataFromJson(forecastJsonStr, numDays);
 183                 } catch (JSONException e) {
 184                     Log.e(LOG_TAG, e.getMessage(), e);
 185                     e.printStackTrace();
 186                 }
 187
 188                 // This will only happen if we fail to read the forecast
 189                 return null;
 190
 191             } catch (IOException e) {
 192                 Log.e(LOG_TAG, "Error ", e);
 193                 // If the code didn't successfully get the weather data, there's no point in attempting
 194                 // to parse it.
 195                 forecastJsonStr = null;
 196             } finally {
 197                 if (urlConnection != null) {
 198                     urlConnection.disconnect();
 199                 }
 200                 if (reader != null) {
 201                     try {
 202                         reader.close();
 203                     } catch (final IOException e) {
 204                         Log.e(LOG_TAG, "Error closing stream", e);
 205                     }
 206                 }
 207             }
 208             return null;
 209         }
 210
 211         /* The date/time conversion code is going to be moved outside the asynctask later,
 212          * so for convenience we're breaking it out into its own method now.
 213          */
 214         private String getReadableDateString(long time) {
 215             // Because the API returns a unix timestamp (measured in seconds),
 216             // it must be converted to milliseconds in order to be converted to valid date.
 217             Date date = new Date(time * 1000);
 218             SimpleDateFormat format = new SimpleDateFormat("E, MMM d");
 219             return format.format(date).toString();
 220         }
 221
 222         /**
 223          * Prepare the weather high/lows for presentation.
 224          */
 225         private String formatHighLows(double high, double low) {
 226             // For presentation, assume the user doesn't care about tenths of a degree.
 227             long roundedHigh = Math.round(high);
 228             long roundedLow = Math.round(low);
 229
 230             String highLowStr = roundedHigh + "/" + roundedLow;
 231             return highLowStr;
 232         }
 233
 234         /**
 235          * Take the String representing the complete forecast in JSON Format and
 236          * pull out the data we need to construct the Strings needed for the wireframes.
 237          * <p/>
 238          * Fortunately parsing is easy:  constructor takes the JSON string and converts it
 239          * into an Object hierarchy for us.
 240          */
 241         private String[] getWeatherDataFromJson(String forecastJsonStr, int numDays)
 242                 throws JSONException {
 243
 244             // These are the names of the JSON objects that need to be extracted.
 245             final String OWM_LIST = "list";
 246             final String OWM_WEATHER = "weather";
 247             final String OWM_TEMPERATURE = "temp";
 248             final String OWM_MAX = "max";
 249             final String OWM_MIN = "min";
 250             final String OWM_DATETIME = "dt";
 251             final String OWM_DESCRIPTION = "main";
 252
 253             JSONObject forecastJson = new JSONObject(forecastJsonStr);
 254             JSONArray weatherArray = forecastJson.getJSONArray(OWM_LIST);
 255
 256             String[] resultStrs = new String[numDays];
 257             for (int i = 0; i < weatherArray.length(); i++) {
 258                 // For now, using the format "Day, description, hi/low"
 259                 String day;
 260                 String description;
 261                 String highAndLow;
 262
 263                 // Get the JSON object representing the day
 264                 JSONObject dayForecast = weatherArray.getJSONObject(i);
 265
 266                 // The date/time is returned as a long.  We need to convert that
 267                 // into something human-readable, since most people won't read "1400356800" as
 268                 // "this saturday".
 269                 long dateTime = dayForecast.getLong(OWM_DATETIME);
 270                 day = getReadableDateString(dateTime);
 271
 272                 // description is in a child array called "weather", which is 1 element long.
 273                 JSONObject weatherObject = dayForecast.getJSONArray(OWM_WEATHER).getJSONObject(0);
 274                 description = weatherObject.getString(OWM_DESCRIPTION);
 275
 276                 // Temperatures are in a child object called "temp".  Try not to name variables
 277                 // "temp" when working with temperature.  It confuses everybody.
 278                 JSONObject temperatureObject = dayForecast.getJSONObject(OWM_TEMPERATURE);
 279                 double high = temperatureObject.getDouble(OWM_MAX);
 280                 double low = temperatureObject.getDouble(OWM_MIN);
 281
 282                 highAndLow = formatHighLows(high, low);
 283                 resultStrs[i] = day + " - " + description + " - " + highAndLow;
 284             }
 285
 286 //            for (String s: resultStrs) {
 287 //                Log.v(LOG_TAG, "Forecast entry: " + s);
 288 //            }
 289             return resultStrs;
 290         }
 291     }
 292 }