在地图上标记用户当前所处位置其实是一个GPS定位应用。首先通过GPS定位获取到用户当前所在位置的经纬度，再将该经纬度所代表的点在地图上标出来。其实除了在地图上标注自己所处的位置外，我们通常还有这样的需求：“如果我的位置发生改变，要能够实时在地图上体现出来”。
新建项目baidumaplocation.设计main.xml文件这里注意的是MapView控件必须使用来自百度库封装好的com.baidu.mapapi.MapView 。设计代码如下：
Xml代码 [url=] [/url]
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<FrameLayout
android:id="@+id/map_layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<!-- 百度MapView控件 -->
<com.baidu.mapapi.MapView
android:id="@+id/map_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:apiKey="0Mg_koWoyZUiYLfZxmPfp4LKInB5LqTnagYueaw"
android:clickable="true"
android:enabled="true" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical"
android:paddingBottom="105dip" >
<!-- 地址信息显示TextView -->
<TextView
android:id="@+id/map_bubbleText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/location_tips"
android:gravity="left|center"
android:maxEms="12"
android:paddingLeft="12dip"
android:paddingRight="10dip"
android:text="@string/load_tips"
android:textColor="#cfcfcf"
android:textSize="14sp" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical" >
<!-- 位置指标显示ImageView -->
<ImageView
android:id="@+id/point_image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginBottom="30dip"
android:src="@drawable/point_start" />
</LinearLayout>
</FrameLayout>
</LinearLayout>
三：创建覆盖整个地图捕捉触控事件的MyMapOverlay继承Overlay
Java代码 [url=] [/url]
import android.view.MotionEvent;
import com.baidu.mapapi.GeoPoint;
import com.baidu.mapapi.MapView;
import com.baidu.mapapi.Overlay;
//覆盖整个地图捕捉触控事件的OverLay
public abstract class MyMapOverlay extends Overlay{
private int point_X;
private int point_Y;
private GeoPoint newPoint;
public MyMapOverlay(int x,int y){
point_X = x;
point_Y = y;
}
boolean flagMove=false;
//这里实现根据地图移动时重新获取屏幕中心点的经纬度坐标
@Override
public boolean onTouchEvent(MotionEvent event, MapView mapView) {
System.out.println("X->"+event.getX()+":"+point_X);
System.out.println("Y->"+event.getY()+":"+point_Y);
if(event.getAction() == MotionEvent.ACTION_DOWN){
changePoint(newPoint,1);
}else if(event.getAction() == MotionEvent.ACTION_UP){
newPoint = mapView.getProjection().fromPixels(point_X,point_Y);
changePoint(newPoint,2);
}
return false;
}
public abstract void changePoint(GeoPoint newPoint,int type);
}
四：LocationActivity类继承百度库的MapActivity以及实现LocationListener接口，代码如下：
package com.location.activity;Java代码 [url=] [/url]
import java.io.IOException;
import java.util.List;import java.util.Locale;
import android.content.Intent;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.Window;
import android.widget.TextView;
import com.android.map.MyMapOverlay;
import com.baidu.mapapi.BMapManager;
import com.baidu.mapapi.GeoPoint;
import com.baidu.mapapi.LocationListener;
import com.baidu.mapapi.MKAddrInfo;
import com.baidu.mapapi.MKBusLineResult;
import com.baidu.mapapi.MKDrivingRouteResult;
import com.baidu.mapapi.MKLocationManager;
import com.baidu.mapapi.MKPoiResult;
import com.baidu.mapapi.MKSearch;
import com.baidu.mapapi.MKSearchListener;
import com.baidu.mapapi.MKSuggestionResult;
import com.baidu.mapapi.MKTransitRouteResult;
import com.baidu.mapapi.MKWalkingRouteResult;
import com.baidu.mapapi.MapActivity;
import com.baidu.mapapi.MapController;
import com.baidu.mapapi.MapView;
import com.baidu.mapapi.Overlay;
public class LocationActivity extends MapActivity implements LocationListener {
private MapView mapView;
private MapController mMapCtrl;
private List<Overlay> mapOverlays;
public GeoPoint locPoint;
private MyMapOverlay mOverlay;
private TextView desText;
private String lost_tips;
private int point_X;
private int point_Y;
public final int MSG_VIEW_LONGPRESS = 10001;
public final int MSG_VIEW_ADDRESSNAME = 10002;
public final int MSG_GONE_ADDRESSNAME = 10003;
private Intent mIntent;
private int mLatitude;
private int mLongitude;
private String name;
private BMapManager mapManager;
private MKLocationManager mLocationManager = null;
private boolean isLoadAdrr = true;
private MKSearch mMKSearch;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.main);
initMap();
mIntent = getIntent();
mLatitude = mIntent.getIntExtra("latitude", 0);
mLongitude = mIntent.getIntExtra("longitude", 0);
name = mIntent.getStringExtra("name");
mapView = (MapView) findViewById(R.id.map_view);
desText = (TextView) this.findViewById(R.id.map_bubbleText);
lost_tips = getResources().getString(R.string.load_tips);
if (mLatitude != 0 && mLongitude != 0) {
locPoint = new GeoPoint((int) (mLatitude * 1E6),
(int) (mLongitude * 1E6));
desText.setText(name);
}
mapView.setBuiltInZoomControls(true);
mapView.setClickable(true);
MapCtrl = mapView.getController();
point_X = this.getWindowManager().getDefaultDisplay().getWidth() / 2;
point_Y = this.getWindowManager().getDefaultDisplay().getHeight() / 2;
mOverlay = new MyMapOverlay(point_X, point_Y) {
@Override
public void changePoint(GeoPoint newPoint, int type) {
if (type == 1) {
mHandler.sendEmptyMessage(MSG_GONE_ADDRESSNAME);
} else {
locPoint = newPoint;
mHandler.sendEmptyMessage(MSG_VIEW_LONGPRESS);
}
}
};
mapOverlays = mapView.getOverlays();
if (mapOverlays.size() > 0) {
mapOverlays.clear();
}
mapOverlays.add(mOverlay);
mMapCtrl.setZoom(20);
}
private void initMap() {
// 初始化MapActivity
mapManager = new BMapManager(getApplication());
// init方法的第一个参数需填入申请的API Key
mapManager.init("C66C0501D0280744759A6957C42543AE38F5D540", null);
super.initMapActivity(mapManager);
// 实例化搜索地址类
mMKSearch = new MKSearch();
// 初始化搜索地址实例
mMKSearch.init(mapManager, new MySearchListener());
mLocationManager = mapManager.getLocationManager();
// 注册位置更新事件
mLocationManager.requestLocationUpdates(this);
// 使用GPS定位
mLocationManager .enableProvider((int) MKLocationManager.MK_GPS_PROVIDER);
}
@Override
protected void onResume() {
if (mapManager != null) {
mapManager.start();
}
super.onResume();
}
@Override
protected void onPause() {
isLoadAdrr = false;
if (mapManager != null) {
mapManager.stop();
}.super.onPause();
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
/** * 通过经纬度获取地址 ** @param point 151. * @return 152. */
private String getLocationAddress(GeoPoint point) {
String add = "";
Geocoder geoCoder = new Geocoder(getBaseContext(), Locale.getDefault());
try {
List<Address> addresses = geoCoder.getFromLocation(
point.getLatitudeE6() / 1E6, point.getLongitudeE6() / 1E6, 1);
Address address = addresses.get(0);
int maxLine = address.getMaxAddressLineIndex();
if (maxLine >= 2) {
add = address.getAddressLine(1) + address.getAddressLine(2);
} else {
add = address.getAddressLine(1);
}
} catch (IOException e) {
add = "";
e.printStackTrace();
}
return add;
}
private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_VIEW_LONGPRESS:// 处理长按时间返回位置信息
{
if (null == locPoint)
return;
mMKSearch.reverseGeocode(locPoint);
desText.setVisibility(View.VISIBLE);
desText.setText(lost_tips);
mMapCtrl.animateTo(locPoint);
mapView.invalidate();
}
break;
case MSG_VIEW_ADDRESSNAME:
desText.setText((String) msg.obj);
desText.setVisibility(View.VISIBLE);
break;
case MSG_GONE_ADDRESSNAME:
desText.setVisibility(View.GONE);
break;
}
}
};
// 关闭程序也关闭定位
@Override 203.
protected void onDestroy() {
if (mapManager != null) {
mapManager.destroy();
mapManager = null;
}
super.onDestroy();
}
/*** 根据MyLocationOverlay配置的属性确定是否在地图上显示当前位置 */
@Override
protected boolean isLocationDisplayed() {
return false;
}
/*** 当位置发生变化时触发此方法 ** @param locatio* 当前位置 */
public void onLocationChanged(Location location) {
if (location != null) {
locPoint = new GeoPoint((int) (location.getLatitude()* 1E6),
(int) (location.getLongitude()* 1E6));
mHandler.sendEmptyMessage(MSG_VIEW_LONGPRESS);
}
}
/*** 内部类实现MKSearchListener接口,用于实现异步搜索服务 ** @author qiaoxu*/
public class MySearchListener implements MKSearchListener {
/*** 根据经纬度搜索地址信息结果
* @param result
*搜索结果
* @param iError
* 错误号（0表示正确返回）
*/
public void onGetAddrResult(MKAddrInfo result, int iError) {
if (result == null) {
return; .
}
Message msg = new Message();
msg.what = MSG_VIEW_ADDRESSNAME;
msg.obj = result.strAddr;
mHandler.sendMessage(msg);
}
/** * 驾车路线搜索结果
* @param result 2
* 搜索结果
* @param iError
* 错误号（0表示正确返回）
*/
public void onGetDrivingRouteResult(MKDrivingRouteResult result, int iError) {
}
/*** POI搜索结果（范围检索、城市POI检索、周边检索*
* @param result
* 搜索结果 275
* @param type
* 返回结果类型（11,12,21:poi列表 7:城市列表）
* @param iError
* 错误号（0表示正确返回）
*/
public void onGetPoiResult(MKPoiResult result, int type, int iError) {
}
/*** 公交换乘路线搜索结果
* @param result
* 搜索结果
* @param iError
* 错误号（0表示正确返回）
*/
public void onGetTransitRouteResult(MKTransitRouteResult result,int iError) {
}
/*** 步行路线搜索结果
* @param result
* 搜索结果
* @param iError
* 错误号（0表示正确返回）
*/
public void onGetWalkingRouteResult(MKWalkingRouteResult result, int iError) {
}
public void onGetBusDetailResult(MKBusLineResult arg0, int arg1) {
// TODO Auto-generated method stub
}
public void onGetSuggestionResult(MKSuggestionResult arg0, int arg1) {
// TODO Auto-generated method stub
}
}
}
五：在AndroidManifest.xml住添加相关的访问权限
<!-- 访问网络的权限 --> Xml代码 [url=]
[/url]
1. <uses-permission android:name="android.permission.INTERNET" />
2. <!-- 访问精确位置的权限 -->
3. <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
4. <!-- 访问网络状态的权限 -->
5. <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
6. <!-- 访问WIFI网络状态的权限 -->
7. <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
8. <!-- 改变WIFI网络状态的权限 -->
9. <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
10. <!-- 读写存储卡的权限 -->
11. <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
12. <!-- 读取电话状态的权限 -->
13.<uses-permission android:name="android.permission.READ_PHONE_STATE" />