Android Google Maps 完整实例分析

第五部分 Google地图
本例实现了一个移动版的个人地图。通够MapView来浏览地图程序和使用Location来实现定位功能。
res.layout.main.xml

xmlns:android=" http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
在Android中有3种地图模式，所以需要设置一个菜单来切换地图的模式。也可以设置一些城市名字来供用户
选择，如果没有自己要选择的城市，可以设置一个拱用户输入城市名字的输入框。
android:id="@+id/MapView01"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:enabled="true"
android:clickable="true"
android:apiKey="0dYpmIXGIdwiVm-HEpzuUW2fjNYsFQ9EvYir1sg"
/>


res.layout.dialog.xml

xmlns:android=" http://schemas.android.com/apk/res/android"
android:gravity="center_horizontal"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
android:id="@+id/TextView01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"/>
android:id="@+id/EditText01"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:selectAllOnFocus="true"
android:scrollHorizontally="true"/>


package com.yarin.android.MobileMap;

public class ConstData{
public static final double[][] cityCode ={
{39.930000,116.279998},//北京
{31.399999,121.470001},//上海
{39.099998,117.169998},//天津
{29.520000,106.480003},//重庆
{39.669998,118.150001},//唐山
{38.029998,114.419998},//石家庄
{38.900001,121.629997},//大连
{45.750000,126.769996},//哈尔滨
{20.030000,110.349998},//海口
{43.900001,125.220001},//长春
{28.229999,112.870002},//长沙
{30.670000,104.019996},//成都
{26.079999,119.279998},//福州
{23.129999,113.319999},//广州
{26.579999,106.720001},//贵阳
{30.229999,120.169998},//杭州
{31.870000,117.230003},//合肥
{40.819999,111.680000},//呼和浩特
{36.680000,116.980003},//济南
{25.020000,102.680000},//昆明
{29.657589,911.32050},//拉萨
{36.040000,103.879997},//兰州
{28.600000,115.919998},//南昌
{32.000000,118.800003},//南京
{22.819999,108.349998},//南宁
{36.069999,120.330001},//青岛
{22.549999,114.099998},//深圳
{41.770000,123.430000},//沈阳
{37.779998,112.550003},//太原
{43.779998,87.620002},//乌鲁木齐
{30.620000,114.129997},//武汉
{34.299999,108.930000},//西安
{36.619998,101.769996},//西宁
{24.479999,118.080001},//厦门
{34.279998,117.150001},//徐州
{38.479999,106.220001},//银川
{34.720001,113.650001}//郑州
};
public static final String [] city ={
"北京",//
"上海",//
"天津",//
"重庆",//
"唐山",//
"石家庄",//
"大连",//
"哈尔滨",//
"海口",//
"长春",//
"长沙",//
"成都",//
"福州",//
"广州",//
"贵阳",//
"杭州",//
"合肥",//
"呼和浩特",//
"济南",//
"昆明",//
"拉萨",//
"兰州",//
"南昌",//
"南京",//
"南宁",//
"青岛",//
"深圳",//
"沈阳",//
"太原",//
"乌鲁木齐",//
"武汉",//
"西安",//
"西宁",//
"厦门",//
"徐州",//
"银川",//
"郑州"//
};
}

public class LocationOverlay extends Overlay{//在定位后显示出当前地点的地址以及一个标示，需要使用Overlay来绘制地图上的信息。
private Location mLocation;
private MobileMap mMobileMap;
private String mAddresses;
public LocationOverlay(MobileMap mobileMap){
mMobileMap = mobileMap;
}
public void setLocation(Location location){
mLocation = location;
mAddresses = getAddresses();
}
public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when){//要在MapView上绘制信息，需要重写Overlay的Draw方法，绘制方法和一般绘图一样
super.draw(canvas, mapView, shadow);
Paint paint = new Paint();
Point scPoint = new Point();
GeoPoint tmpGeoPoint = new GeoPoint((int)(mLocation.getLatitude()*1E6),(int)(mLocation.getLongitude()*1E6));
mapView.getProjection().toPixels(tmpGeoPoint, scPoint);//通过toPixels方法将经度和纬度的信息转换成屏幕上对象的像素坐标信息。

paint.setStrokeWidth(1);
paint.setARGB(255, 255, 0, 0);
paint.setStyle(Paint.Style.STROKE);
paint.setFlags(Paint.ANTI_ALIAS_FLAG);//消除字体的锯齿效果
paint.setTextSize(16);

Bitmap bmp = BitmapFactory.decodeResource(mMobileMap.getResources(), R.drawable.mark);
canvas.drawBitmap(bmp, scPoint.x-bmp.getWidth()/2, scPoint.y-bmp.getHeight(), paint);
canvas.drawText(mAddresses, scPoint.x-paint.measureText(mAddresses)/2, scPoint.y, paint);
return true;
}
public String getAddresses(){
String addressString="没有找到地址";
Geocoder gc=new Geocoder(mMobileMap,Locale.getDefault());
try{
List

addresses=gc.getFromLocation(mLocation.getLatitude(), mLocation.getLongitude(),1);//在绘制之前需要得到当前地点的地址信息，
Geocoder为我们提供了getFromLocation方法来获得地址等信息。
StringBuilder sb=new StringBuilder();
if(addresses.size()>0){
Address address = addresses.get(0);
sb.append("地址：");
for (int i = 0; i < address.getMaxAddressLineIndex(); i++){
sb.append(address.getAddressLine(i));
}
addressString=sb.toString();
}
}catch(IOException e){
}
return addressString;
}
}

public class MobileMap extends MapActivity{//MapActivity用于浏览地图，定位信息处理以及一些菜单事件的处理，我们程序中定义了一些城市的名字供用户选择，在
选择之后将通过该城市所对应的经度和纬度的数据来进行定位。当用户输入城市名字的时候，可以通过Geocoder.getFromLocationName
方法将名字转换成地址，然后找到最合适的城市进行定位
private MapViewmMapView;
private MapControllermMapController;
private GeocodermGeocoder;
private LocationOverlaymLocationOverlay;
private LocationManager mlocationManager;
private Location mLocation;

private static final intSearch= Menu.FIRST;
private static final intSelectCity= Menu.FIRST + 1;
private static final intViewMode= Menu.FIRST + 2;
private static final intExit= Menu.FIRST + 3;

public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
init();
}
protected boolean isRouteDisplayed(){
return false;
}
public void init(){
mMapView=(MapView)findViewById(R.id.MapView01);
mMapController=mMapView.getController(); //取得MapController实例，控制地图
mlocationManager=(LocationManager)getSystemService(Context.LOCATION_SERVICE);
mMapView.setEnabled(true);
mMapView.setClickable(true);
mMapView.setTraffic(false);//设置显示模式
mMapView.setSatellite(false);
mMapView.setStreetView(true);
mMapView.setBuiltInZoomControls(true); //设置缩放
mMapController.setZoom(12);//设置地图等级

mLocationOverlay=new LocationOverlay(this);
List overlays=mMapView.getOverlays();
overlays.add(mLocationOverlay);

Criteria criteria =new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE); //经度要求
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(false);
criteria.setPowerRequirement(Criteria.POWER_LOW);

String provider=mlocationManager.getBestProvider(criteria, true);//取得效果最好的criteria
mLocation=mlocationManager.getLastKnownLocation(provider); //得到坐标相关的信息
mGeocoder = new Geocoder(this,Locale.getDefault());
updateLocation(mLocation);
mlocationManager.requestLocationUpdates(provider, 3000, 0,mLocationListener);
}
public void updateLocation(Location location) {//更新定位
if ( location == null ){
return;
}
mLocationOverlay.setLocation(location);
Double geoLat=location.getLatitude()*1E6;
Double geoLng=location.getLongitude()*1E6;
GeoPoint point=new GeoPoint(geoLat.intValue(),geoLng.intValue()); //将其转换为int型
mMapController.animateTo(point); //定位到指定坐标
}
public MapController getMapController(){
return mMapController;
}
private final LocationListener mLocationListener=new LocationListener(){
public void onLocationChanged(Location location){
updateLocation(location);
}
public void onProviderDisabled(String provider){
}
public void onProviderEnabled(String provider){
}
public void onStatusChanged(String provider,int status,Bundle extras){
}
};
public boolean onCreateOptionsMenu(Menu menu){
super.onCreateOptionsMenu(menu);
menu.add(0, Search, Menu.NONE, "搜索地点").setIcon(R.drawable.search);
menu.add(0, SelectCity, Menu.NONE, "选择城市").setIcon(R.drawable.selectcity);
menu.add(0, ViewMode, Menu.NONE, "地图模式").setIcon(R.drawable.viewmode);
menu.add(0, Exit, Menu.NONE, "退出").setIcon(R.drawable.exit);
return true;
}
public boolean onOptionsItemSelected(MenuItem item){
super.onOptionsItemSelected(item);
switch (item.getItemId()){
case Search:
searchCity();
return true;
case SelectCity:
selectCity();
return true;
case ViewMode:
selectViewMode();
return true;
case Exit:
this.finish();
return true;
}
return true;
}
public void selectCity(){ //选择城市
OnClickListener listener = new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which){
Double geoLat=ConstData.cityCode[which][0]*1E6;
Double geoLng=ConstData.cityCode[which][1]*1E6;

mLocation.setLatitude(ConstData.cityCode[which][0]);
mLocation.setLongitude(ConstData.cityCode[which][1]);
mLocationOverlay.setLocation(mLocation);
GeoPoint point=new GeoPoint(geoLat.intValue(),geoLng.intValue());
mMapController.animateTo(point);//定位到指定坐标
}
};
ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_spinner_item, ConstData.city);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
new AlertDialog.Builder(MobileMap.this)
.setTitle("请选择城市")
.setAdapter(adapter, listener)
.show();
}
public void selectViewMode(){ //选择地图模式
OnClickListener listener = new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which){
switch ( which ){
case 0:
mMapView.setTraffic(false);
mMapView.setSatellite(false);
mMapView.setStreetView(true);
break;
case 1:
mMapView.setSatellite(false);
mMapView.setStreetView(false);
mMapView.setTraffic(true);
break;
case 2:
mMapView.setStreetView(false);
mMapView.setTraffic(false);
mMapView.setSatellite(true);
break;
}
}
};
String[] menu={"街景模式","交通流量","卫星地图"};
new AlertDialog.Builder(MobileMap.this)
.setTitle("请选择地图模式")
.setItems(menu, listener)
.show();
}
public void searchCity(){ //搜索城市
//自定义一个带输入的对话框由TextView和EditText构成
final LayoutInflater factory = LayoutInflater.from(MobileMap.this);
final View dialogview = factory.inflate(R.layout.dialog, null);
((TextView) dialogview.findViewById(R.id.TextView01)).setText("搜索地图");//设置TextView的提示信息
((EditText) dialogview.findViewById(R.id.EditText01)).setText("请输入要查找的地址...");//设置EditText输入框初始值
Builder builder = new Builder(MobileMap.this);
builder.setTitle("请输入地名");
builder.setView(dialogview);
builder.setPositiveButton(android.R.string.ok,new AlertDialog.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
String value = ((EditText) dialogview.findViewById(R.id.EditText01)).getText().toString().trim();//点击确定之后
if ( value != "" ){
searchName(value);
}
}
});
builder.setNegativeButton(android.R.string.cancel,new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
builder.setOnCancelListener(new DialogInterface.OnCancelListener() {
public void onCancel(DialogInterface dialog) {
dialog.cancel();
}
});
builder.show();
}
public void searchName(String nameStr){
try{
List

addresses = mGeocoder.getFromLocationName(nameStr, 1);
if (addresses.size() != 0){
Address address = addresses.get(0);
GeoPoint geoPoint = new GeoPoint((int) (address.getLatitude() * 1E6), (int) (address.getLongitude() * 1E6));
mLocation.setLatitude(address.getLatitude());
mLocation.setLongitude(address.getLongitude());
mLocationOverlay.setLocation(mLocation);
mMapController.animateTo(geoPoint);
}
}
catch (IOException e){}
}
}
AndroidManifest.xml

xmlns:android="http://schemas.android.com/apk/res/android"
package="com.yarin.android.MobileMap"
android:versionCode="1"
android:versionName="1.0">
android:icon="@drawable/icon"
android:label="@string/app_name">

android:name=".MobileMap"
android:label="@string/app_name">





//因为使用了com.google.android.maps所以需要声明权限。如果要发布应用程序需要申请Google的API Key