12 .Android Location的使用

大家好，今天说说Android Location，Location在Android开发中还是经常用到的，比如通过经纬度获取天气，根据Location获取所在地区详细地址（比如Google Map开发)等。而在Android中通过LocationManager来获取Location，通常获取Location有GPS获取、WIFI获取。

我今天做一个简单的小Demo，来教大家如何获取Location，从而获取经纬度。下一节将教大家通过Location来获取Address。

第一步：创建一个Android工程命名为LocationDemo

第二步：修改main.xml代码如下:

<? xml version = "1.0" encoding = "utf-8" ?>
< LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android"
    android:orientation = "vertical"
    android:layout_width = "fill_parent"
    android:layout_height = "fill_parent" >
    < TextView
        android:id = "@+id/longitude"
        android:layout_width = "fill_parent"
        android:layout_height = "wrap_content"
        android:text = "longitude:"
        />
    < TextView
        android:id = "@+id/latitude"
        android:layout_width = "fill_parent"
        android:layout_height = "wrap_content"
        android:text = "latitude:"
        />
</ LinearLayout >

第三步：修改LocationDemo.java，代码如下：

package com.android.tutor;

import android.app.Activity;
import android.content.Context;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;

public class LocationDemo extends Activity {

    private TextView longitude;
    private TextView latitude;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super .onCreate(savedInstanceState);
        setContentView(R.layout.main);

        longitude = (TextView) findViewById(R.id.longitude);
        latitude = (TextView) findViewById(R.id.latitude);

        Location mLocation = getLocation( this );

        longitude.setText( "Longitude: " + mLocation.getLongitude());
        latitude.setText( "Latitude: " + mLocation.getLatitude());
    }

    // Get the Location by GPS or WIFI
    public Location getLocation(Context context) {
        LocationManager locMan = (LocationManager) context
                .getSystemService(Context.LOCATION_SERVICE);
        Location location = locMan
                .getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if (location == null ) {
            location = locMan
                    .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
        }
        return location;
    }
}

第四步：增加权限，修改AndroidManifest.xml代码如下（第14行为所增行）：

<? xml version = "1.0" encoding = "utf-8" ?>
< manifest xmlns:android = "http://schemas.android.com/apk/res/android"
    package = "com.android.tutor" android:versionCode = "1"
    android:versionName = "1.0" >
    < application android:icon = "@drawable/icon" android:label = "@string/app_name" >
        < activity android:name = ".LocationDemo" android:label = "@string/app_name" >
            < intent-filter >
                < action android:name = "android.intent.action.MAIN" />
                < category android:name = "android.intent.category.LAUNCHER" />
            </ intent-filter >
        </ activity >
    </ application >
    < uses-sdk android:minSdkVersion = "7" />
    < uses-permission android:name = "android.permission.ACCESS_FINE_LOCATION" />
</ manifest >

第五步：运行LocationDemo工程，所得效果如下(真机深圳测试)：