Android开发如何利用Google map
自google 06年进入中国，在地图、移动领域的发展速度基本上都是每年几倍的增长。在最新的Android平台开发相关应用程序，如果能深入了解google map 将会对我们Android开发提供很大的帮助.以下是我总结的在Android开发中对google map的理解。
1. 首先先要获取你的debug keystore位置：
打开Eclipse--->Windows---> preferences--->Android--->Build
查看默认的debug keystore位置，我的是C:\Documents and Settings\sdhbk\.android\debug.keystore
2.
D:\android-sdk-windows-1.5_r1\tools>keytool -list -alias androiddebugkey -keysto
re "C:\Documents and Settings\sdhbk\.android\debug.keystore" -storepass android
-keypass android
androiddebugkey, 2009-7-25, PrivateKeyEntry,
认证指纹 (MD5)： DA:D5:6E:C2:80:D1:0F:0D:F8:2A:58:6A:74:7C:CE:2D
3.
?? 打开http://code.google.com/intl/zh-CN/android/maps-api-signup.html
填入你的认证指纹(MD5)即可获得apiKey了,结果显示如下：
???????? 感谢您注册 Android 地图 API 密钥！
??????????? 您的密钥是：
?????? XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
4.?????? 使用得到的apiKey:
????????????? 在layout中加入MapView
????????????? <com.google.android.maps.MapView
????????????????????? android:id="@+id/mapview"
????????????????????? android:layout_width="fill_parent"
????????????????????? android:layout_height="fill_parent"
????????????????????? android:apiKey="0jOkQ80oD1JL9C6HAja99uGXCRiS2CGjKO_bc_g" />
? 或者
? <view android:id="@+id/mv"
??
?? android:apiKey="0jOkQ80oD1JL9C6HAja99uGXCRiS2CGjKO_bc_g"
?? />
5.Android在sdk1.5的预装的add-on中提供了一个Map扩展库com.google.android.maps，利用它你就可以给你的android应用程序增加上强大的地图功能了。这个库的位置在Your-SDK_DIR\add-ons\google_apis-3\libs.
一定要在manifest.xml中设置全相应的权限，比如：
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
要在manifest.xml中加上要用的maps库：
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.package.name">
? ...
? <application android:name="MyApplication" >
??? <uses-library android:name="com.google.android.maps" />
??? ...
? </application>
? ...
</manifest>
需要说明的是这个库不是标准的android sdk的内容，你也可以自己从这里这里下载并放到你的sdk里面。
Maps库分析
Maps库提供了十几个类，具体可以参考这里http://code.google.com/intl/ja/android/add-ons/google-apis/reference/index.html,? 包括Mapview，MapController，MapActivity等。
Mapview是用来显示地图的view, 它也是派生自android.view.ViewGroup。
地图可以以不同的形式来显示出来，如街景模式，卫星模式等，具体方法可以参考：
setSatellite(boolean), setTraffic(boolean), and setStreetView(boolean)
MapView只能被MapActivity来创建，这是因为mapview需要通过后台的线程来连接网络或者文件系统，而这些线程要由mapActivity来管理。
需要特别说明的一点是，android 1.5中，map的zoom采用了built-in机制，可以通过setBuiltInZoomControls(boolean)来设置是否在地图上显示zoom控件。
MapActivity是一个抽象类，任何想要显示MapView的activity都需要派生自MapActivity。并且在其派生类的onCreate()中，都要创建一个MapView实例，可以通过MapView constructor (then add it to a layout View with ViewGroup.addView(View)) 或者通过layout XML来创建。
实例分析
最后，按照惯例，还是用一个小程序来演示一下android中地图功能的开发。主要功能是实现了地图的缩放，添加了菜单，从而可以手动选择地图的显示模式等。
Step 1: 新建一个android project, 注意这里要选择的build target为"Google APIs"
Step 2: 修改menifest文件：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
????? package="com.map.prac"
????? android:versionCode="1"
????? android:versionName="1.0">
??? <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
??? <uses-permission android:name="android.permission.INTERNET" />
??? <application android:icon="@drawable/icon" android:label="@string/app_name">
??? <uses-library android:name="com.google.android.maps" />
??????? <activity android:name=".MapViewPrac2"
????????????????? 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="3" />
</manifest>
Step 3: 修改layout文件，main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
??? android:id="@+id/main"
??? android:layout_width="fill_parent"
??? android:layout_height="fill_parent">
??? <com.google.android.maps.MapView
??????? android:id="@+id/map"
??????? android:layout_width="fill_parent"
??????? android:layout_height="fill_parent"
??????? android:enabled="true"
??????? android:clickable="true"
??????? android:apiKey="???????????????????????????????????"
??????? />
</LinearLayout>
这里需要将api key中的????????????改成你自己申请到的api key.
Step 4: 修改代码：
package com.map.prac;
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 android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.util.Log;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
public class MapViewPrac2 extends MapActivity {
??? private final String TAG = "MapPrac";
??? private MapView mapView = null;
??? private MapController mc;
??? //Menu items
??? final private int menuMode = Menu.FIRST;
??? final private int menuExit = Menu.FIRST+1;
??? final private int menuCommandList = Menu.FIRST + 2;
??? private int chooseItem = 0;
??? /** Called when the activity is first created. */
??? @Override
??? public void onCreate(Bundle savedInstanceState) {
??????? super.onCreate(savedInstanceState);
??????? setContentView(R.layout.main);
??????? mapView = (MapView)findViewById(R.id.map);
??????? mc = mapView.getController();
??????? mapView.setTraffic(true); //
??????? mapView.setSatellite(false);
??????? mapView.setStreetView(true);
??????? //GeoPoint gp = new GeoPoint((int)(39.269259 * 1000000), (int)(115.255762 * 1000000));//yixian
??????? GeoPoint gp = new GeoPoint((int)(39.95 * 1000000), (int)(116.37 * 1000000));//beijing
??????? //mc.animateTo(gp);
??????? //mc.setZoom(12);
??????? mc.setCenter(gp);
??????? //to display zoom control in MapView
??????? mapView.setBuiltInZoomControls(true);
??? }
??? @Override
??? public boolean onKeyDown(int keyCode, KeyEvent event) {
??????? // TODO Auto-generated method stub
??????? Log.i(TAG,"enter onKeyDown");
??????? return super.onKeyDown(keyCode, event);
??? }
??? @Override
??? public boolean onCreateOptionsMenu(Menu menu) {
??????? menu.add(0, menuMode, 0, "Map Mode");
??????? menu.add(0, menuCommandList, 1, "Command List");
??????? menu.add(0, menuExit, 2, "Exit");
??????? return super.onCreateOptionsMenu(menu);
??? }
??? @Override
??? public boolean onMenuItemSelected(int featureId, MenuItem item) {
??????? // TODO Auto-generated method stub
??????? switch(item.getItemId())
??????? {
??????? case menuMode:
??????????? Dialog dMode = new AlertDialog.Builder(this)
??????????? //.setIcon(R.drawable.alert_dialog_icon)
??????????? .setTitle(R.string.alert_dialog_single_choice)
??????????? .setSingleChoiceItems(R.array.select_dialog_items2, chooseItem, new DialogInterface.OnClickListener() {
??????????????? public void onClick(DialogInterface dialog, int whichButton) {
??????????????????? Log.i(TAG, "choose button is "+ whichButton);
??????????????????? chooseItem = whichButton;
??????????????????? /* User clicked on a radio button do some stuff */
??????????????? }
??????????? })
??????????? .setPositiveButton(R.string.alert_dialog_ok, new DialogInterface.OnClickListener() {
??????????????? public void onClick(DialogInterface dialog, int whichButton) {
??????????????????? /* User clicked Yes so do some stuff */
??????????????????? Log.i(TAG,"item = "+chooseItem);
??????????????????? switch(chooseItem)
??????????????????? {
??????????????????? case 0:
??????????????????????? mapView.setSatellite(false);
??????????????????????? break;
??????????????????? case 1:
??????????????????????? mapView.setSatellite(true);
??????????????????????? break;
??????????????????? case 2:
??????????????????????? mapView.setTraffic(true);
??????????????????????? break;
??????????????????? case 3:
??????????????????????? mapView.setStreetView(true);
??????????????????????? break;
??????????????????? default:
??????????????????????? break;
??????????????????? }
??????????????? }
??????????? })
??????????? .setNegativeButton(R.string.alert_dialog_cancel, new DialogInterface.OnClickListener() {
??????????????? public void onClick(DialogInterface dialog, int whichButton) {
??????????????????? /* User clicked No so do some stuff */
??????????????? }
??????????? })
?????????? .create();
??????????? dMode.show();
??????????? break;
??????? case menuCommandList:
??????????? //create the dialog
??????????? Dialog d = new AlertDialog.Builder(this)
??????????? .setTitle(R.string.select_dialog)
??????????? .setItems(R.array.select_dialog_items, new DialogInterface.OnClickListener() {
??????????????? public void onClick(DialogInterface dialog, int which) {
??????????????????? /* User clicked so do some stuff */
??????????????????? String[] items = getResources().getStringArray(R.array.select_dialog_items);
??????????????????? /*new AlertDialog.Builder(this)
??????????????????????????? .setMessage("You selected: " + which + " , " + items[which])
??????????????????????????? .show();*/
??????????????????? Log.i(TAG,"you choose is: " + items[which]);
??????????????? }
??????????? })
??????????? .create();
??????????? //show the dialog
??????????? d.show();
??????????? break;
??????? case menuExit:
??????????? finish();
??????????? break;
??????? default:
??????????????? break;
??????? }
??????? return super.onMenuItemSelected(featureId, item);
??? }
??? @Override
??? protected boolean isRouteDisplayed() {
??????? // TODO Auto-generated method stub
??????? return false;
??? }
}
关于google map的用法还有待各位Android开发人员在实际开发中的总结！
