无法使用Google Services Google Maps V2运行Android项目

Question

我正在尝试运行一个简单的显示地图的android项目。

我已经遵循了Google Maps链接中的所有步骤，但eclipse只是阻止尝试启动该项目。

1-我将google-play-services_lib添加到工作区。2-我在工作区中复制了它。3-我用这些创建了一个android项目：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.mapasimple"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
    android:minSdkVersion="12"
    android:targetSdkVersion="21" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<!-- The following two permissions are not required to use
 Google Maps Android API v2, but are recommended. -->
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
 <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
  <uses-feature
    android:glEsVersion="0x00020000"
    android:required="true"/>
 <application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".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>
 <meta-data
      android:name="com.google.android.maps.v2.API_KEY" android:value="xxxxxxxx-kfjDVu3590eOxjhrVSc"/>
    <meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
 </application>
</manifest>

import android.app.Activity;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;
public class MainActivity extends  Activity{
    @Override
    protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
           requestWindowFeature(Window.FEATURE_NO_TITLE); this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
            setContentView(R.layout.activity_main);
        }
}       

<?xml version="1.0" encoding="utf-8"?>
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/map"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:name="com.google.android.gms.maps.MapFragment"/>

当我尝试运行该项目时，eclipse块经过了一点时间的处理。

默认情况下会选中Android私有库和Android依赖项。如果取消选中其中一个，eclipse也会阻塞。如果取消选中这两个选项,eclipse将运行该项目,但出现以下错误：

我尝试了这些不同的事情，但没有成功：

null

import android.app.Activity;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Toast;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
public class MainActivity extends  Activity{
GoogleMap googleMap;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
           requestWindowFeature(Window.FEATURE_NO_TITLE); this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
            setContentView(R.layout.activity_main);
     initilizeMap();
     }
    private void initilizeMap() {
        if (googleMap == null) {
            googleMap = ((MapFragment) ((Activity) getApplicationContext()).getFragmentManager()
                    .findFragmentById(R.id.map)).getMap();
 // check if map is created successfully or not
            if (googleMap == null) {
                Toast.makeText(
                        getApplicationContext().getApplicationContext(),
                        "googlemap null",
                        Toast.LENGTH_SHORT).show();
             }
        }
    }
}       

已更新@Predactor答案

现在看来android找不到MainActivity类了。我重新制作了项目，重新执行所有步骤，并在一个新的工作区中重新制作，但总是出现以下错误：

Answer 1

在主活动中添加以下内容

private GoogleMap mMap;

在onCreate方法中添加

setUpMapIfNeeded();

在onCreate方法下，添加这个

private void setUpMapIfNeeded() {
    // Do a null check to confirm that we have not already instantiated the
    // map.
    if (mMap == null) {
        // Try to obtain the map from the SupportMapFragment.
        mMap = ((SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map)).getExtendedMap();
        // Check if we were successful in obtaining the map.
        if (mMap != null) {
            setUpMap();
        }
    }
}

private void setUpMap() {

    mMap.setMapType(GoogleMap.MAP_TYPE_SATELLITE);

    }

}

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