F32

At a Glance

F32 is a library for temperature conversions and weather forecasts. It includes wrapper for OpenWeatherMap API and provides developer with super-simple way to obtain weather information by geographic coordinates, city name and ZIP code.

Components included in F32:

• OpenWeatherMap API wrapper (current weather and forecast)
• Temperature converter
• Temperature formatter

How To Get Started

Use gradle dependency: compile 'com.visuality.f32forandroid:f32:2.4'

Requirements

• Android Studio 2.3 or later
• Java 7 or later
• Android 4.0.3 or later

Usage

Preparations For Weather Requests

Before making requests for weather forecast, sign up here and get API key (if you don't already have one).

Also, don't forget to append INTERNET permission to your application's manifest file:

<uses-permission android:name="android.permission.INTERNET"/>

Current weather

Below you can see how to make request for current weather:

/*
 * Request for current weather using coordinates.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getCurrentWeatherByCoordinates(
        47.2257, // latitude
        38.9383, // longitude
        new WeatherManager.CurrentWeatherHandler() {
            @Override
            public void onReceivedCurrentWeather(WeatherManager manager, Weather weather) {
                // Handle current weather information
            }

            @Override
            public void onFailedToReceiveCurrentWeather(WeatherManager manager) {
                // Handle error
            }
        }
);

/*
 * Request for current weather using city name.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getCurrentWeatherByCityName(
        "New York", // city name
        new WeatherManager.CurrentWeatherHandler() {
            @Override
            public void onReceivedCurrentWeather(WeatherManager manager, Weather weather) {
                // Handle current weather information
            }

            @Override
            public void onFailedToReceiveCurrentWeather(WeatherManager manager) {
                // Handle error
            }
        }
);

/*
 * Request for current weather using city ID.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getCurrentWeatherByCityId(
        2172797, // city id
        new WeatherManager.CurrentWeatherHandler() {
            @Override
            public void onReceivedCurrentWeather(WeatherManager manager, Weather weather) {
                // Handle current weather information
            }

            @Override
            public void onFailedToReceiveCurrentWeather(WeatherManager manager) {
                // Handle error
            }
        }
);

/*
 * Request for current weather using ZIP code.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getCurrentWeatherByZipCode(
        "94040", // ZIP code
        "us", // country code
        new WeatherManager.CurrentWeatherHandler() {
            @Override
            public void onReceivedCurrentWeather(WeatherManager manager, Weather weather) {
                // Handle current weather information
            }

            @Override
            public void onFailedToReceiveCurrentWeather(WeatherManager manager) {
                // Handle error
            }
        }
);

Weather class

Object of Weather type can tell you a lot of information:

/*
 * Location name.
 */

String locationName = weather.getNavigation().getLocationName();

/*
 * Latitude of the place.
 */

double latitude = weather.getNavigation().getCoordinate().getLatitude();

/*
 * Longitude of the place.
 */

double longitude = weather.getNavigation().getCoordinate().getLongitude();

/*
 * Sea level.
 */

double seaLevel = weather.getNavigation().getSeaLevel();

/*
 * Ground level.
 */

double groundLevel = weather.getNavigation().getGroundLevel();

/*
 * Current temperature in Kelvin.
 */

double currentTemperatureInKelvin = weather.getTemperature().getCurrent()
    .getValue(TemperatureUnit.KELVIN);

/*
 * Current temperature in Celcius.
 */

double currentTemperatureInCelcius = weather.getTemperature().getCurrent()
    .getValue(TemperatureUnit.CELCIUS);

/*
 * Current temperature in Fahrenheit.
 */

double currentTemperatureInFahrenheit = weather.getTemperature().getCurrent()
    .getValue(TemperatureUnit.FAHRENHEIT);

/*
 * Minimum temperature in Kelvin.
 */

double minimumTemperatureInKelvin = weather.getTemperature().getMinimum()
    .getValue(TemperatureUnit.KELVIN);

/*
 * Minimum temperature in Celcius.
 */

double minimumTemperatureInCelcius = weather.getTemperature().getMinimum()
    .getValue(TemperatureUnit.CELCIUS);

/*
 * Minimum temperature in Fahrenheit.
 */

double minimumTemperatureInFahrenheit = weather.getTemperature().getMinimum()
    .getValue(TemperatureUnit.FAHRENHEIT);

/*
 * Maximum temperature in Kelvin.
 */

double maximumTemperatureInKelvin = weather.getTemperature().getMaximum()
    .getValue(TemperatureUnit.KELVIN);

/*
 * Maximum temperature in Celcius.
 */

double maximumTemperatureInCelcius = weather.getTemperature().getMaximum()
    .getValue(TemperatureUnit.CELCIUS);

/*
 * Maximum temperature in Fahrenheit.
 */

double maximumTemperatureInFahrenheit = weather.getTemperature().getMaximum()
    .getValue(TemperatureUnit.FAHRENHEIT);

/*
 * Sunrise timestamp.
 */

long sunriseTimestamp = weather.getLight().getSunriseTimestamp();

/*
 * Sunset timestamp.
 */

long sunsetTimestamp = weather.getLight().getSunsetTimestamp();

/*
 * Pressure in hectopascal.
 */

double pressureInHectopascal = weather.getAtmosphere().getPressure().getValue(AtmosphericPressure.Unit.HECTOPASCAL);

/*
 * Pressure in millimeter of Mercury.
 */

double pressureInMillimeterOfMercury = weather.getAtmosphere().getPressure().getValue(AtmosphericPressure.Unit.MILLIMETER_OF_MERCURY);

/*
 * Humidity.
 */

int humidityPercentage = weather.getAtmosphere().getHumidityPercentage();

/*
 * Wind speed in meters per second.
 */

double windSpeed = weather.getWind().getSpeed();

/*
 * Wind direction in degrees.
 */

double direction = weather.getWind().getDirection();

/*
 * Cloudiness in percents.
 */

int cloudinessPercentage = weather.getCloudiness().getPercentage();

/*
 * Rain volume for last three hours.
 */

double rainThreeHoursVolume = weather.getRain().getThreeHoursVolume();

/*
 * Snow volume for last three hours.
 */

double snowThreeHoursVolume = weather.getSnow().getThreeHoursVolume();

/*
 * Weather timestamp.
 */

long weatherTimestamp = weather.getWeatherTimestamp();

Forecast

Example of request for 5 day forecast:

/*
 * Request for 5 day forecast using coordinates.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getFiveDayForecastByCoordinates(
        47.2257, // latitude
        38.9383, // longitude
        new WeatherManager.ForecastHandler() {
            @Override
            public void onReceivedForecast(WeatherManager manager, Forecast forecast) {
                // Handle forecast
            }

            @Override
            public void onFailedToReceiveForecast(WeatherManager manager) {
                // Handle error...
            }
        }
);

/*
 * Request for 5 day forecast using city name.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getFiveDayForecastByCityName(
        "New York", // city name
        new WeatherManager.ForecastHandler() {
            @Override
            public void onReceivedForecast(WeatherManager manager, Forecast forecast) {
                // Handle forecast
            }

            @Override
            public void onFailedToReceiveForecast(WeatherManager manager) {
                // Handle error...
            }
        }
);

/*
 * Request for 5 day forecast using city ID.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getFiveDayForecastByCityId(
        2172797, // city id
        new WeatherManager.ForecastHandler() {
            @Override
            public void onReceivedForecast(WeatherManager manager, Forecast forecast) {
                // Handle forecast
            }

            @Override
            public void onFailedToReceiveForecast(WeatherManager manager) {
                // Handle error...
            }
        }
);

/*
 * Request for 5 day forecast using ZIP code.
 */

new WeatherManager("INSERT_YOUR_API_KEY_HERE").getFiveDayForecastByZipCode(
        "94040", // ZIP code
        "us", // country code
        new WeatherManager.ForecastHandler() {
            @Override
            public void onReceivedForecast(WeatherManager manager, Forecast forecast) {
                // Handle forecast
            }

            @Override
            public void onFailedToReceiveForecast(WeatherManager manager) {
                // Handle error...
            }
        }
);

If request was successful, handler returns object of Forecast type. Forecast is a set of weathers for different timestamps. For example, forecast may include weather for today's 4 PM, today's 7 PM, tomorrow's 8 AM, etc. Below you can see example of usage:

new WeatherManager(API_KEY).getFiveDayForecastByCoordinates(
        47.2257,
        38.9383,
        new WeatherManager.ForecastHandler() {
            @Override
            public void onReceivedForecast(WeatherManager manager, Forecast forecast) {
                // Example of handling forecast.
                
                int numberOfAvailableTimestamps = forecast.getNumberOfTimestamps();
                
                for (int timestampIndex = 0; timestampIndex < numberOfAvailableTimestamps; timestampIndex++) {
                    long timestamp = forecast.getTimestampByIndex(timestampIndex);
                    Weather weatherForTimestamp = forecast.getWeatherForTimestamp(timestamp);
                    // Do something with weather information...
                }
            }

            @Override
            public void onFailedToReceiveForecast(WeatherManager manager) {
                // Handle error...
            }
        }
);

Also, you can request the most appropriate weather for random timestamp:

new WeatherManager(API_KEY).getFiveDayForecastByCoordinates(
        47.2257,
        38.9383,
        new WeatherManager.ForecastHandler() {
            @Override
            public void onReceivedForecast(WeatherManager manager, Forecast forecast) {
                // Example of handling forecast.
                
                long rightNow = System.currentTimeMillis() / 1000;
                
                long inOneHour = rightNow + TimeUnit.HOURS.toSeconds(1);
                Weather weatherInOneHour = forecast.getWeatherForTimestamp(inOneHour);
                
                long afterTwoDays = rightNow + TimeUnit.DAYS.toSeconds(2);
                Weather weatherInTwoDays = forecast.getWeatherForTimestamp(afterTwoDays);
            }

            @Override
            public void onFailedToReceiveForecast(WeatherManager manager) {
                // Handle error...
            }
        }
);

You can simply check earliest and latest available timestamp:

long earliestAvailableTimestamp = forecast.getEarliestTimestamp();
long latestAvailableTimestamp = forecast.getLatestTimestamp();

Temperature Conversions

You can easily convert temperature from Kelvin to Celcius, from Celcius to Fahrenheit, etc. Use Temperature class for that:

Temperature temperature = new Temperature(32, TemperatureUnit.FAHRENHEIT);
double temperatureInFahrenheit = temperature.getValue(TemperatureUnit.FAHRENHEIT); // 32.0 degrees
double temperatureInCelcius = temperature.getValue(TemperatureUnit.CELCIUS); // 0.0 degrees
double temperatureInKelvin = temperature.getValue(TemperatureUnit.KELVIN); // 273.15 degrees

Full list of supported temperature scales:

• Celcius
• Delisle
• Fahrenheit
• Kelvin
• Rankine
• Réaumur
• Rømer

Temperature Formatter

Before displaying temperature in the app, you need to convert it to string. It's recommended to use TemperatureFormatter class for this purpose:

/*
 * Format temperature with no digits after decimal point.
 */

String temperatureWithoutDecimalPoint = new TemperatureFormatter().getStringFromTemperature(
        32.0,
        TemperatureUnit.FAHRENHEIT
);

Log.d("TemperatureFormatter", temperatureWithoutDecimalPoint); // "32 °F"

/*
 * Format temperature with digit after decimal point.
 */

String temperatureWithDecimalPoint = new TemperatureFormatter().getStringFromTemperature(
        273.15,
        TemperatureUnit.KELVIN
);

Log.d("TemperatureFormatter", temperatureWithDecimalPoint); // "273.15 °K"

License

F32 is available under the MIT license. See the LICENSE file for more info.