Java tutorial
/* * Copyright (C) 2015 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.android.sunshine.app; import android.content.Context; import android.content.SharedPreferences; import android.content.res.Resources; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.preference.PreferenceManager; import android.support.v4.content.res.ResourcesCompat; import android.text.format.Time; import com.example.android.sunshine.app.sync.SunshineSyncAdapter; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Locale; public class Utility { public static String getPreferredLocation(Context context) { SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context); return prefs.getString(context.getString(R.string.pref_location_key), context.getString(R.string.pref_location_default)); } public static String getPreferredAPI(Context context) { SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context); return prefs.getString(context.getString(R.string.pref_api_key), context.getString(R.string.pref_api_key_default)); } public static boolean isMetric(Context context) { SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context); return prefs .getString(context.getString(R.string.pref_units_key), context.getString(R.string.pref_units_metric)) .equals(context.getString(R.string.pref_units_metric)); } public static String formatTemperature(Context context, double temperature) { // Data stored in Celsius by default. If user prefers to see in Fahrenheit, convert // the values here. String suffix = "\u00B0"; if (!isMetric(context)) { temperature = (temperature * 1.8) + 32; } // For presentation, assume the user doesn't care about tenths of a degree. return String.format(context.getString(R.string.format_temperature), temperature); } static String formatDate(long dateInMilliseconds) { Date date = new Date(dateInMilliseconds); return DateFormat.getDateInstance().format(date); } // Format used for storing dates in the database. ALso used for converting those strings // back into date objects for comparison/processing. public static final String DATE_FORMAT = "yyyyMMdd"; /** * Helper method to convert the database representation of the date into something to display * to users. As classy and polished a user experience as "20140102" is, we can do better. * * @param context Context to use for resource localization * @param dateInMillis The date in milliseconds * @return a user-friendly representation of the date. */ public static String getFriendlyDayString(Context context, long dateInMillis, boolean displayLongToday) { // The day string for forecast uses the following logic: // For today: "Today, June 8" // For tomorrow: "Tomorrow" // For the next 5 days: "Wednesday" (just the day name) // For all days after that: "Mon Jun 8" Time time = new Time(); time.setToNow(); long currentTime = System.currentTimeMillis(); int julianDay = Time.getJulianDay(dateInMillis, time.gmtoff); int currentJulianDay = Time.getJulianDay(currentTime, time.gmtoff); // If the date we're building the String for is today's date, the format // is "Today, June 24" if (displayLongToday && julianDay == currentJulianDay) { String today = context.getString(R.string.today); int formatId = R.string.format_full_friendly_date; return String.format(context.getString(formatId, today, getFormattedMonthDay(context, dateInMillis))); } else if (julianDay < currentJulianDay + 7) { // If the input date is less than a week in the future, just return the day name. return getDayName(context, dateInMillis); } else { // Otherwise, use the form "Mon Jun 3" SimpleDateFormat shortenedDateFormat = new SimpleDateFormat("EEE MMM dd"); return shortenedDateFormat.format(dateInMillis); } } /** * Helper method to convert the database representation of the date into something to display * to users. As classy and polished a user experience as "20140102" is, we can do better. * * @param context Context to use for resource localization * @param dateInMillis The date in milliseconds * @return a user-friendly representation of the date. */ public static String getFullFriendlyDayString(Context context, long dateInMillis) { String day = getDayName(context, dateInMillis); int formatId = R.string.format_full_friendly_date; return String.format(context.getString(formatId, day, getFormattedMonthDay(context, dateInMillis))); } /** * Given a day, returns just the name to use for that day. * E.g "today", "tomorrow", "wednesday". * * @param context Context to use for resource localization * @param dateInMillis The date in milliseconds * @return */ public static String getDayName(Context context, long dateInMillis) { // If the date is today, return the localized version of "Today" instead of the actual // day name. Time t = new Time(); t.setToNow(); int julianDay = Time.getJulianDay(dateInMillis, t.gmtoff); int currentJulianDay = Time.getJulianDay(System.currentTimeMillis(), t.gmtoff); if (julianDay == currentJulianDay) { return context.getString(R.string.today); } else if (julianDay == currentJulianDay + 1) { return context.getString(R.string.tomorrow); } else { Time time = new Time(); time.setToNow(); // Otherwise, the format is just the day of the week (e.g "Wednesday". SimpleDateFormat dayFormat = new SimpleDateFormat("EEEE"); return dayFormat.format(dateInMillis); } } /** * Converts db date format to the format "Month day", e.g "June 24". * @param context Context to use for resource localization * @param dateInMillis The db formatted date string, expected to be of the form specified * in Utility.DATE_FORMAT * @return The day in the form of a string formatted "December 6" */ public static String getFormattedMonthDay(Context context, long dateInMillis) { Time time = new Time(); time.setToNow(); SimpleDateFormat dbDateFormat = new SimpleDateFormat(Utility.DATE_FORMAT); SimpleDateFormat monthDayFormat = new SimpleDateFormat("MMMM dd"); String monthDayString = monthDayFormat.format(dateInMillis); return monthDayString; } public static String getFormattedWind(Context context, float windSpeed, float degrees) { int windFormat; if (Utility.isMetric(context)) { windFormat = R.string.format_wind_kmh; } else { windFormat = R.string.format_wind_mph; windSpeed = .621371192237334f * windSpeed; } // From wind direction in degrees, determine compass direction as a string (e.g NW) // You know what's fun, writing really long if/else statements with tons of possible // conditions. Seriously, try it! String direction = "Unknown"; if (degrees >= 337.5 || degrees < 22.5) { direction = "N"; } else if (degrees >= 22.5 && degrees < 67.5) { direction = "NE"; } else if (degrees >= 67.5 && degrees < 112.5) { direction = "E"; } else if (degrees >= 112.5 && degrees < 157.5) { direction = "SE"; } else if (degrees >= 157.5 && degrees < 202.5) { direction = "S"; } else if (degrees >= 202.5 && degrees < 247.5) { direction = "SW"; } else if (degrees >= 247.5 && degrees < 292.5) { direction = "W"; } else if (degrees >= 292.5 && degrees < 337.5) { direction = "NW"; } return String.format(context.getString(windFormat), windSpeed, direction); } /** * Helper method to provide the icon resource id according to the weather condition id returned * by the OpenWeatherMap call. * @param weatherId from OpenWeatherMap API response * @return resource id for the corresponding icon. -1 if no relation is found. */ public static int getIconResourceForWeatherCondition(int weatherId) { // Based on weather code data found at: // http://bugs.openweathermap.org/projects/api/wiki/Weather_Condition_Codes if (weatherId >= 200 && weatherId <= 232) { return R.drawable.ic_storm; } else if (weatherId >= 300 && weatherId <= 321) { return R.drawable.ic_light_rain; } else if (weatherId >= 500 && weatherId <= 504) { return R.drawable.ic_rain; } else if (weatherId == 511) { return R.drawable.ic_snow; } else if (weatherId >= 520 && weatherId <= 531) { return R.drawable.ic_rain; } else if (weatherId >= 600 && weatherId <= 622) { return R.drawable.ic_snow; } else if (weatherId >= 701 && weatherId <= 761) { return R.drawable.ic_fog; } else if (weatherId == 761 || weatherId == 781) { return R.drawable.ic_storm; } else if (weatherId == 800) { return R.drawable.ic_clear; } else if (weatherId == 801) { return R.drawable.ic_light_clouds; } else if (weatherId >= 802 && weatherId <= 804) { return R.drawable.ic_cloudy; } return -1; } /** * Helper method to return whether or not Sunshine is using local graphics. * * @param context Context to use for retrieving the preference * @return true if Sunshine is using local graphics, false otherwise. */ public static boolean usingLocalGraphics(Context context) { SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context); String sunshineArtPack = context.getString(R.string.pref_art_pack_sunshine); return prefs.getString(context.getString(R.string.pref_art_pack_key), sunshineArtPack) .equals(sunshineArtPack); } /** * Helper method to provide the art urls according to the weather condition id returned * by the OpenWeatherMap call. * * @param context Context to use for retrieving the URL format * @param weatherId from OpenWeatherMap API response * @return url for the corresponding weather artwork. null if no relation is found. */ public static String getArtUrlForWeatherCondition(Context context, int weatherId) { SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context); String formatArtUrl = prefs.getString(context.getString(R.string.pref_art_pack_key), context.getString(R.string.pref_art_pack_sunshine)); // Based on weather code data found at: // http://bugs.openweathermap.org/projects/api/wiki/Weather_Condition_Codes if (weatherId >= 200 && weatherId <= 232) { return String.format(Locale.US, formatArtUrl, "storm"); } else if (weatherId >= 300 && weatherId <= 321) { return String.format(Locale.US, formatArtUrl, "light_rain"); } else if (weatherId >= 500 && weatherId <= 504) { return String.format(Locale.US, formatArtUrl, "rain"); } else if (weatherId == 511) { return String.format(Locale.US, formatArtUrl, "snow"); } else if (weatherId >= 520 && weatherId <= 531) { return String.format(Locale.US, formatArtUrl, "rain"); } else if (weatherId >= 600 && weatherId <= 622) { return String.format(Locale.US, formatArtUrl, "snow"); } else if (weatherId >= 701 && weatherId <= 761) { return String.format(Locale.US, formatArtUrl, "fog"); } else if (weatherId == 761 || weatherId == 781) { return String.format(Locale.US, formatArtUrl, "storm"); } else if (weatherId == 800) { return String.format(Locale.US, formatArtUrl, "clear"); } else if (weatherId == 801) { return String.format(Locale.US, formatArtUrl, "light_clouds"); } else if (weatherId >= 802 && weatherId <= 804) { return String.format(Locale.US, formatArtUrl, "clouds"); } return null; } /** * Helper method to provide the art resource id according to the weather condition id returned * by the OpenWeatherMap call. * @param weatherId from OpenWeatherMap API response * @return resource id for the corresponding icon. -1 if no relation is found. */ public static int getArtResourceForWeatherCondition(int weatherId) { // Based on weather code data found at: // http://bugs.openweathermap.org/projects/api/wiki/Weather_Condition_Codes if (weatherId >= 200 && weatherId <= 232) { return R.drawable.art_storm; } else if (weatherId >= 300 && weatherId <= 321) { return R.drawable.art_light_rain; } else if (weatherId >= 500 && weatherId <= 504) { return R.drawable.art_rain; } else if (weatherId == 511) { return R.drawable.art_snow; } else if (weatherId >= 520 && weatherId <= 531) { return R.drawable.art_rain; } else if (weatherId >= 600 && weatherId <= 622) { return R.drawable.art_snow; } else if (weatherId >= 701 && weatherId <= 761) { return R.drawable.art_fog; } else if (weatherId == 761 || weatherId == 781) { return R.drawable.art_storm; } else if (weatherId == 800) { return R.drawable.art_clear; } else if (weatherId == 801) { return R.drawable.art_light_clouds; } else if (weatherId >= 802 && weatherId <= 804) { return R.drawable.art_clouds; } return -1; } /** * Helper method to provide the string according to the weather * condition id returned by the OpenWeatherMap call. * @param context Android context * @param weatherId from OpenWeatherMap API response * @return string for the weather condition. null if no relation is found. */ public static String getStringForWeatherCondition(Context context, int weatherId) { // Based on weather code data found at: // http://bugs.openweathermap.org/projects/api/wiki/Weather_Condition_Codes int stringId; if (weatherId >= 200 && weatherId <= 232) { stringId = R.string.condition_2xx; } else if (weatherId >= 300 && weatherId <= 321) { stringId = R.string.condition_3xx; } else switch (weatherId) { case 500: stringId = R.string.condition_500; break; case 501: stringId = R.string.condition_501; break; case 502: stringId = R.string.condition_502; break; case 503: stringId = R.string.condition_503; break; case 504: stringId = R.string.condition_504; break; case 511: stringId = R.string.condition_511; break; case 520: stringId = R.string.condition_520; break; case 531: stringId = R.string.condition_531; break; case 600: stringId = R.string.condition_600; break; case 601: stringId = R.string.condition_601; break; case 602: stringId = R.string.condition_602; break; case 611: stringId = R.string.condition_611; break; case 612: stringId = R.string.condition_612; break; case 615: stringId = R.string.condition_615; break; case 616: stringId = R.string.condition_616; break; case 620: stringId = R.string.condition_620; break; case 621: stringId = R.string.condition_621; break; case 622: stringId = R.string.condition_622; break; case 701: stringId = R.string.condition_701; break; case 711: stringId = R.string.condition_711; break; case 721: stringId = R.string.condition_721; break; case 731: stringId = R.string.condition_731; break; case 741: stringId = R.string.condition_741; break; case 751: stringId = R.string.condition_751; break; case 761: stringId = R.string.condition_761; break; case 762: stringId = R.string.condition_762; break; case 771: stringId = R.string.condition_771; break; case 781: stringId = R.string.condition_781; break; case 800: stringId = R.string.condition_800; break; case 801: stringId = R.string.condition_801; break; case 802: stringId = R.string.condition_802; break; case 803: stringId = R.string.condition_803; break; case 804: stringId = R.string.condition_804; break; case 900: stringId = R.string.condition_900; break; case 901: stringId = R.string.condition_901; break; case 902: stringId = R.string.condition_902; break; case 903: stringId = R.string.condition_903; break; case 904: stringId = R.string.condition_904; break; case 905: stringId = R.string.condition_905; break; case 906: stringId = R.string.condition_906; break; case 951: stringId = R.string.condition_951; break; case 952: stringId = R.string.condition_952; break; case 953: stringId = R.string.condition_953; break; case 954: stringId = R.string.condition_954; break; case 955: stringId = R.string.condition_955; break; case 956: stringId = R.string.condition_956; break; case 957: stringId = R.string.condition_957; break; case 958: stringId = R.string.condition_958; break; case 959: stringId = R.string.condition_959; break; case 960: stringId = R.string.condition_960; break; case 961: stringId = R.string.condition_961; break; case 962: stringId = R.string.condition_962; break; default: return context.getString(R.string.condition_unknown, weatherId); } return context.getString(stringId); } /* * Helper method to provide the correct image according to the weather condition id returned * by the OpenWeatherMap call. * * @param weatherId from OpenWeatherMap API response * @return A string URL to an appropriate image or null if no mapping is found */ public static String getImageUrlForWeatherCondition(int weatherId) { // Based on weather code data found at: // http://bugs.openweathermap.org/projects/api/wiki/Weather_Condition_Codes if (weatherId >= 200 && weatherId <= 232) { return "http://upload.wikimedia.org/wikipedia/commons/2/28/Thunderstorm_in_Annemasse,_France.jpg"; } else if (weatherId >= 300 && weatherId <= 321) { return "http://upload.wikimedia.org/wikipedia/commons/a/a0/Rain_on_leaf_504605006.jpg"; } else if (weatherId >= 500 && weatherId <= 504) { return "http://upload.wikimedia.org/wikipedia/commons/6/6c/Rain-on-Thassos.jpg"; } else if (weatherId == 511) { return "http://upload.wikimedia.org/wikipedia/commons/b/b8/Fresh_snow.JPG"; } else if (weatherId >= 520 && weatherId <= 531) { return "http://upload.wikimedia.org/wikipedia/commons/6/6c/Rain-on-Thassos.jpg"; } else if (weatherId >= 600 && weatherId <= 622) { return "http://upload.wikimedia.org/wikipedia/commons/b/b8/Fresh_snow.JPG"; } else if (weatherId >= 701 && weatherId <= 761) { return "http://upload.wikimedia.org/wikipedia/commons/e/e6/Westminster_fog_-_London_-_UK.jpg"; } else if (weatherId == 761 || weatherId == 781) { return "http://upload.wikimedia.org/wikipedia/commons/d/dc/Raised_dust_ahead_of_a_severe_thunderstorm_1.jpg"; } else if (weatherId == 800) { return "http://upload.wikimedia.org/wikipedia/commons/7/7e/A_few_trees_and_the_sun_(6009964513).jpg"; } else if (weatherId == 801) { return "http://upload.wikimedia.org/wikipedia/commons/e/e7/Cloudy_Blue_Sky_(5031259890).jpg"; } else if (weatherId >= 802 && weatherId <= 804) { return "http://upload.wikimedia.org/wikipedia/commons/5/54/Cloudy_hills_in_Elis,_Greece_2.jpg"; } return null; } /** * Returns true if the network is available or about to become available. * * @param c Context used to get the ConnectivityManager * @return true if the network is available */ static public boolean isNetworkAvailable(Context c) { ConnectivityManager cm = (ConnectivityManager) c.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo activeNetwork = cm.getActiveNetworkInfo(); return activeNetwork != null && activeNetwork.isConnectedOrConnecting(); } /** * * @param c Context used to get the SharedPreferences * @return the location status integer type */ @SuppressWarnings("ResourceType") static public @SunshineSyncAdapter.LocationStatus int getLocationStatus(Context c) { SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(c); return sp.getInt(c.getString(R.string.pref_location_status_key), SunshineSyncAdapter.LOCATION_STATUS_UNKNOWN); } /** * Resets the location status. (Sets it to SunshineSyncAdapter.LOCATION_STATUS_UNKNOWN) * @param c Context used to get the SharedPreferences */ static public void resetLocationStatus(Context c) { SharedPreferences sp = PreferenceManager.getDefaultSharedPreferences(c); SharedPreferences.Editor spe = sp.edit(); spe.putInt(c.getString(R.string.pref_location_status_key), SunshineSyncAdapter.LOCATION_STATUS_UNKNOWN); spe.apply(); } }