MapView学习Demo2

main.xml:

<?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:layout_width="fill_parent"
		android:layout_height="wrap_content"
		android:id="@+id/TextView01" />
	<com.google.android.maps.MapView
		android:id="@+id/MapView01"
		android:layout_width="fill_parent"
		android:layout_height="fill_parent"
		android:apiKey="0axCo4Wu7FStW2yuF-kfg0X8Rr50919GvKpiCrA" />
</LinearLayout>

AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest
	xmlns:android="http://schemas.android.com/apk/res/android"
	package="com.magus.location"
	android:versionCode="1"
	android:versionName="1.0">
	<uses-sdk
		android:minSdkVersion="8" />

	<application
		android:icon="@drawable/icon"
		android:label="@string/app_name">
		<uses-library
			android:name="com.google.android.maps" />
		<activity
			android:name="Activity01"
			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-permission
		android:name="android.permission.INTERNET" />
	<uses-permission
		android:name="android.permission.ACCESS_COARSE_LOCATION" />
	<uses-permission
		android:name="android.permission.ACCESS_FINE_LOCATION" />
</manifest>

Activity01:

package com.magus.location;

import java.io.IOException;
import java.util.List;
import java.util.Locale;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Point;
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.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

public class Activity01 extends MapActivity {
	public MapController mapController;
	public MyLocationOverlay myPosition;
	public MapView myMapView;
	private static final int ZOOM_IN = Menu.FIRST;
	private static final int ZOOM_OUT = Menu.FIRST + 1;

	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		// 取得LocationManager实例
		LocationManager locationManager;
		String context = Context.LOCATION_SERVICE;
		locationManager = (LocationManager) getSystemService(context);
		myMapView = (MapView) findViewById(R.id.MapView01);
		// 取得MapController实例，控制地图
		mapController = myMapView.getController();
		// 设置显示模式
		myMapView.setSatellite(true);
		myMapView.setStreetView(true);
		// 设置缩放控制,这里我们自己实现缩放菜单
		myMapView.displayZoomControls(false);
		// 设置使用MyLocationOverlay来绘图
		mapController.setZoom(17);
		myPosition = new MyLocationOverlay();
		List<Overlay> overlays = myMapView.getOverlays();
		overlays.add(myPosition);
		// 设置Criteria（服务商）的信息
		Criteria criteria = new Criteria();
		// 经度要求
		criteria.setAccuracy(Criteria.ACCURACY_FINE);
		criteria.setAltitudeRequired(false);
		criteria.setBearingRequired(false);
		criteria.setCostAllowed(false);
		criteria.setPowerRequirement(Criteria.POWER_LOW);
		// 取得效果最好的criteria
		String provider = locationManager.getBestProvider(criteria, true);
		// 得到坐标相关的信息
		Location location = locationManager.getLastKnownLocation(provider);
		// 更新坐标
		updateWithNewLocation(location);
		// 注册一个周期性的更新，3000ms更新一次
		// locationListener用来监听定位信息的改变
		locationManager.requestLocationUpdates(provider, 3000, 0,
				locationListener);
	}

	private void updateWithNewLocation(Location location) {
		String latLongString;
		TextView myLocationText = (TextView) findViewById(R.id.TextView01);
		String addressString = "没有找到地址\n";
		if (location != null) {
			// 为绘制标志的类设置坐标
			myPosition.setLocation(location);
			// 取得经度和纬度
			Double geoLat = location.getLatitude() * 1E6;
			Double geoLng = location.getLongitude() * 1E6;
			// 将其转换为int型
			GeoPoint point = new GeoPoint(geoLat.intValue(), geoLng.intValue());
			// 定位到指定坐标
			mapController.animateTo(point);
			double lat = location.getLatitude();
			double lng = location.getLongitude();
			latLongString = "经度：" + lat + "\n纬度：" + lng;
			double latitude = location.getLatitude();
			double longitude = location.getLongitude();
			// 根据地理环境来确定编码
			Geocoder gc = new Geocoder(this, Locale.getDefault());
			try {
				// 取得地址相关的一些信息、经度、纬度
				List<Address> addresses = gc.getFromLocation(latitude,
						longitude, 1);
				StringBuilder sb = new StringBuilder();
				if (addresses.size() > 0) {
					Address address = addresses.get(0);
					for (int i = 0; i < address.getMaxAddressLineIndex(); i++)
						sb.append(address.getAddressLine(i)).append("\n");
					sb.append(address.getLocality()).append("\n");
					sb.append(address.getPostalCode()).append("\n");
					sb.append(address.getCountryName());
					addressString = sb.toString();
				}
			} catch (IOException e) {
			}
		} else {
			latLongString = "没有找到坐标.\n";
		}
		// 显示
		myLocationText.setText("你当前的坐标如下:\n" + latLongString + "\n"
				+ addressString);
	}

	private final LocationListener locationListener = new LocationListener() {
		// 当坐标改变时触发此函数
		public void onLocationChanged(Location location) {
			updateWithNewLocation(location);
		}

		// Provider禁用时触发此函数，比如GPS被关闭
		public void onProviderDisabled(String provider) {
			updateWithNewLocation(null);
		}

		// Provider启用时触发此函数，比如GPS被打开
		public void onProviderEnabled(String provider) {
		}

		// Provider的转态在可用、暂时不可用和无服务三个状态直接切换时触发此函数
		public void onStatusChanged(String provider, int status, Bundle extras) {
		}
	};

	protected boolean isRouteDisplayed() {
		return false;
	}

	// 为应用程序添加菜单
	public boolean onCreateOptionsMenu(Menu menu) {
		super.onCreateOptionsMenu(menu);
		menu.add(0, ZOOM_IN, Menu.NONE, "放大");
		menu.add(0, ZOOM_OUT, Menu.NONE, "缩小");
		return true;
	}

	public boolean onOptionsItemSelected(MenuItem item) {
		super.onOptionsItemSelected(item);
		switch (item.getItemId()) {
		case (ZOOM_IN):
			// 放大
			mapController.zoomIn();
			return true;
		case (ZOOM_OUT):
			// 缩小
			mapController.zoomOut();
			return true;
		}
		return true;
	}

	class MyLocationOverlay extends Overlay {
		Location mLocation;

		// 在更新坐标时，设置该坐标，以便画图
		public void setLocation(Location location) {
			mLocation = location;
		}

		@Override
		public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
				long when) {
			super.draw(canvas, mapView, shadow);
			Paint paint = new Paint();
			Point myScreenCoords = new Point();
			// 将经纬度转换成实际屏幕坐标
			GeoPoint tmpGeoPoint = new GeoPoint(
					(int) (mLocation.getLatitude() * 1E6), (int) (mLocation
							.getLongitude() * 1E6));
			
			//模拟器上运行时必须先给定一个坐标，否则报空指针，真机运行时打开上面的注释
			//GeoPoint tmpGeoPoint = new GeoPoint(35410000, 139460000);
			mapView.getProjection().toPixels(tmpGeoPoint, myScreenCoords);
			paint.setStrokeWidth(1);
			paint.setARGB(255, 255, 0, 0);
			paint.setStyle(Paint.Style.STROKE);
			Bitmap bmp = BitmapFactory.decodeResource(getResources(),
					R.drawable.home);
			canvas.drawBitmap(bmp, myScreenCoords.x, myScreenCoords.y, paint);
			canvas.drawText("Here am I", myScreenCoords.x, myScreenCoords.y,
					paint);
			return true;
		}
	}
}