Java tutorial
/* * Copyright 2015. Appsi Mobile * * 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.appsimobile.appsii; import android.content.Context; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.os.AsyncTask; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.annotation.RequiresPermission; import android.support.v4.util.CircularArray; import android.util.Log; import com.appsimobile.appsii.dagger.AppInjector; import com.appsimobile.appsii.module.weather.loader.CantGetWeatherException; import com.appsimobile.appsii.module.weather.loader.YahooWeatherApiClient; import java.lang.ref.WeakReference; import static android.Manifest.permission.ACCESS_COARSE_LOCATION; import static android.Manifest.permission.ACCESS_FINE_LOCATION; /** * Utility helper to load location info * Created by nick on 18/06/15. */ public class LocationLoader { final LocationReceiver mLocationReceiver; LocationManager mLocationManager; AsyncTask<Location, Void, YahooWeatherApiClient.LocationInfo> mTask; /** * True when the loader has been destroyed */ boolean mDestroyed; private LocationListenerImpl mLocationListener; public LocationLoader(LocationReceiver locationReceiver) { mLocationReceiver = locationReceiver; mLocationManager = AppInjector.provideLocationManager(); } @RequiresPermission(anyOf = { ACCESS_COARSE_LOCATION, ACCESS_FINE_LOCATION }) public boolean requestLocationUpdate(Context context) throws SecurityException { if (!mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) { return false; } Location lastKnown = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); if (lastKnown != null) { onLocationChanged(lastKnown); } mLocationListener = new LocationListenerImpl(this); mLocationManager.requestSingleUpdate(LocationManager.NETWORK_PROVIDER, mLocationListener, null); return true; } public void onLocationChanged(final Location location) { if (mDestroyed) return; if (mTask != null) { mTask.cancel(true); } mTask = new AsyncTask<Location, Void, YahooWeatherApiClient.LocationInfo>() { @Override protected YahooWeatherApiClient.LocationInfo doInBackground(Location... locations) { Location location = locations[0]; try { return YahooWeatherApiClient.getLocationInfo(location); } catch (CantGetWeatherException e) { Log.w("WeatherFragment", "Error getting locationInfo", e); return null; } } @Override protected void onPostExecute(YahooWeatherApiClient.LocationInfo locationInfo) { onLocationInfoLoaded(locationInfo); } }; mTask.execute(location); } void onLocationInfoLoaded(@Nullable YahooWeatherApiClient.LocationInfo locationInfo) { CircularArray<String> woeids = locationInfo == null ? null : locationInfo.woeids; String town = locationInfo == null ? null : locationInfo.town; String country = locationInfo == null ? null : locationInfo.country; String timezone = locationInfo == null ? null : locationInfo.timezone; Log.i("WeatherFragment", "town: " + town + " country: " + country + " woeids: " + woeids); if (woeids != null && town != null) { String woeid = woeids.get(0); mLocationReceiver.onCurrentLocationInfoReady(woeid, country, town, timezone); } else { mLocationReceiver.onCurrentLocationInfoReady(null, null, null, null); } } public void destroy() { mDestroyed = true; if (mLocationListener != null) { mLocationListener.destroy(); } if (mTask != null) { mTask.cancel(true); } } private static class LocationListenerImpl implements LocationListener { WeakReference<LocationLoader> mLocationLoaderRef; public LocationListenerImpl(LocationLoader locationLoader) { mLocationLoaderRef = new WeakReference<>(locationLoader); } @Override public void onLocationChanged(Location location) { LocationLoader locationLoader = mLocationLoaderRef.get(); if (locationLoader != null) { locationLoader.onLocationChanged(location); } } @Override public void onStatusChanged(String provider, int status, Bundle extras) { } @Override public void onProviderEnabled(String provider) { } @Override public void onProviderDisabled(String provider) { } public void destroy() { mLocationLoaderRef.clear(); } } }