2015/9/10问题集
Android取得经纬度
从中取得经纬度。
记得要添加权限
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
-
package com.zsz.develop.gpsfixdemo;
import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.widget.Toast;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
public class GPSActivity extends AppCompatActivity {
String latLongString;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_gps);
init();
}
private void init() {
/**
*取得系统位置管理的引用，
*getSystem这个一定要在activity里面引用
*/
LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
LocationListener locationListener = new LocationListener() {
@Override
public void onLocationChanged(Location location) {
makeUseOfNewLocation(location);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
};
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
}
private void makeUseOfNewLocation(Location location) {
TextView tv1;
tv1 = (TextView) this.findViewById(R.id.tv1);
if (location != null) {
double latitude = location.getLatitude();
double longitude= location.getLongitude();
tv1.setText("维度：" + latitude+ "\n经度" + longitude);
} else {
tv1.setText("无法获取地理信息");
}
}
如果还要将经纬度转化为城市
package com.zsz.develop.gpsfixdemo;
import android.Manifest;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Criteria;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.provider.Settings;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import android.widget.Toast;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;
public class GPSActivity extends AppCompatActivity {
String latLongString;
double latitude;
double longitude;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_gps);
init();
}
private void init() {
openGPSSettings();
getLaction();
}
private void openGPSSettings() {
LocationManager alm = (LocationManager) this
.getSystemService(Context.LOCATION_SERVICE);
if (alm
.isProviderEnabled(android.location.LocationManager.GPS_PROVIDER)) {
Toast.makeText(this, "GPS模块正常", Toast.LENGTH_SHORT)
.show();
Log.w("gps ", "正常");
return;
}
Toast.makeText(this, "请开启GPS！", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(Settings.ACTION_SECURITY_SETTINGS);
startActivityForResult(intent, 0);
}
private void getLaction(){
/**
*取得系统位置管理的引用，
*getSystem这个一定要在activity里面引用
*/
LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
String serviceName = Context.LOCATION_SERVICE;
locationManager = (LocationManager) this.getSystemService(serviceName);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
String provider = locationManager.getBestProvider(criteria, true);
LocationListener locationListener = new LocationListener() {
@Override
public void onLocationChanged(Location location) {
makeUseOfNewLocation(location);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
};
locationManager.requestLocationUpdates(provider, 1000 * 60, 100, locationListener);
}
private void makeUseOfNewLocation(Location location) {
TextView tv1;
tv1 = (TextView) this.findViewById(R.id.tv1);
if (location != null) {
latitude = location.getLatitude();
longitude= location.getLongitude();
tv1.setText("维度：" + latitude+ "\n经度" + longitude);
} else {
tv1.setText("无法获取地理信息");
}
List<Address> addList = null;
Geocoder ge = new Geocoder(this);
try {
addList = ge.getFromLocation(latitude, longitude, 2);
tv1.append(addList+"");
} catch (IOException e) {
e.printStackTrace();
}
if(addList!=null && addList.size()>0){
for(int i=0; i<addList.size(); i++){
Address ad = addList.get(i);
latLongString += "\n";
latLongString += ad.getCountryName() + ";" + ad.getLocality();
tv1.append("您当前的位置是:\n" + latLongString);
}
}
}
}
Location服务之Geocoder
提到Android基于位置的服务，就不得不提android.location包，
location包提供了很便捷的API来实现基于位置的服务。主要包括Geocoder和LocationManager。今天就先来介绍一下Geocoder。
Geocoder可以在街道地址和经纬度地图坐标之间进行转换。它提供了对两种地理编码功能的访问：
Forward Geocoding(前向地理编码)：查找某个地址的经纬度
Reverse Geocoding(反向地理编码)：查找一个给定的经纬度所对应的街道地址。
Location获取地理位置信息（中）Criteria类的简单使用
在使用android lcoation的时候，可能不希望自己去硬性的选择是GPS服务还是NETWORK服务，可能是我们考虑的因素有很多，自己很难决定，Android SDK提供了一个类Criteria，直译为标准。
//翻译：返回满足给定的criteria(标准)的最佳provider，（前面一篇文章提到过两种重要provider的区别）。只有当provider权限允许的时候才会返回，如果几个provider均满足criteria设定的标准，最贴近标准的provider将会被返回。如果没有provider满足，标准将按照下面的序列放宽松。
