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我有这样的活动类代码：

package com.pavel.exchanger;

import android.os.Bundle;
import android.app.Activity;
import android.support.v4.app.FragmentActivity;
import android.view.Menu;

import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import android.support.v4.app.Fragment;


public class SearchExchangerActivity extends FragmentActivity   {
    static final LatLng HAMBURG = new LatLng(53.558, 9.927);
    static final LatLng KIEL = new LatLng(53.551, 9.993);
    private GoogleMap map;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_search_exchanger);

        map = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
                .getMap();
            Marker hamburg = map.addMarker(new MarkerOptions().position(HAMBURG)
                .title("Hamburg"));
            Marker kiel = map.addMarker(new MarkerOptions()
                .position(KIEL)
                .title("Kiel")
                .snippet("Kiel is cool")
                .icon(BitmapDescriptorFactory
                    .fromResource(R.drawable.ic_launcher)));

            // Move the camera instantly to hamburg with a zoom of 15.
            map.moveCamera(CameraUpdateFactory.newLatLngZoom(HAMBURG, 15));

            // Zoom in, animating the camera.
            map.animateCamera(CameraUpdateFactory.zoomTo(10), 2000, null);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.search_exchanger, menu);
        return true;
    }

}

和这样的布局：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".SearchExchangerActivity" >

    <fragment
        android:id="@+id/map"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        class="com.google.android.gms.maps.SupportMapFragment"/>

</RelativeLayout>

和这样的清单：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.pavel.exchanger"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="10"
        android:targetSdkVersion="10" />

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="com.pavel.exchanger.permission.MAPS_RECEIVE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    <permission
        android:name="com.pavel.exchanger.permission.MAPS_RECEIVE"
        android:protectionLevel="signature" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.pavel.exchanger.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name="com.pavel.exchanger.ExchangerListActivity"
            android:label="@string/title_activity_exchanger_list" >
        </activity>
        <activity
            android:name="com.pavel.exchanger.BankExchangersListActivity"
            android:label="@string/title_activity_bank_exchangers_list" >
        </activity>
        <activity
            android:name="com.pavel.exchanger.NbrbActivity"
            android:label="@string/title_activity_nbrb" >
        </activity>

        <meta-data
            android:name="com.google.android.maps.v2.***"
            android:value="****" />

        <activity
            android:name="com.pavel.exchanger.SearchExchangerActivity"
            android:label="@string/title_activity_search_exchanger" >
        </activity>
    </application>

</manifest>

但是当我运行我的活动时，我得到：

04-30 21:39:32.856: E/AndroidRuntime(435): FATAL EXCEPTION: main
04-30 21:39:32.856: E/AndroidRuntime(435): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.pavel.exchanger/com.pavel.exchanger.SearchExchangerActivity}: java.lang.NullPointerException
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.app.ActivityThread.access$1500(ActivityThread.java:117)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.os.Handler.dispatchMessage(Handler.java:99)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.os.Looper.loop(Looper.java:123)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.app.ActivityThread.main(ActivityThread.java:3683)
04-30 21:39:32.856: E/AndroidRuntime(435):  at java.lang.reflect.Method.invokeNative(Native Method)
04-30 21:39:32.856: E/AndroidRuntime(435):  at java.lang.reflect.Method.invoke(Method.java:507)
04-30 21:39:32.856: E/AndroidRuntime(435):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
04-30 21:39:32.856: E/AndroidRuntime(435):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
04-30 21:39:32.856: E/AndroidRuntime(435):  at dalvik.system.NativeStart.main(Native Method)
04-30 21:39:32.856: E/AndroidRuntime(435): Caused by: java.lang.NullPointerException
04-30 21:39:32.856: E/AndroidRuntime(435):  at com.pavel.exchanger.SearchExchangerActivity.onCreate(SearchExchangerActivity.java:29)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
04-30 21:39:32.856: E/AndroidRuntime(435):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
04-30 21:39:32.856: E/AndroidRuntime(435):  ... 11 more

包括所有库和项目（谷歌播放）....

但为什么我会收到这个错误？我如何在 2.3.3 上看到谷歌地图？？？

另外，如果我在活动中执行此类代码（默认）：

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_search_exchanger);  
    }

在模拟器中，我看到我需要安装 google play 应用程序......

如何在 android 2.3.3 上运行 google maps api v2???

4

1 回答 1

1

Android 模拟器不支持 Google Play 服务 - 要使用 API 进行开发，您需要提供开发设备，例如 Android 手机或平板电脑。

以上引用来自http://developer.android.com/google/play-services/setup.html。

我建议您在设备上运行您的应用程序。

编辑：

如果您的目标应用程序早于 API 级别 12，则可以通过 SupportMapFragment 类访问相同的功能。您还必须包括 支持库。

于 2013-04-30T21:48:50.583 回答