android中的Mapapi v2导致片段错误

Question

我在地图实现中遇到的问题很少fragment.以下是我的代码.

import android.app.Fragment;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
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.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.tfick.android.R;

public class PoiFragment extends Fragment{

private GoogleMap mGoogleMap;

private static final LatLng SYDNEY = new LatLng(23.03,72.62);

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    View v=inflater.inflate(R.layout.poi_fragment, container,false);


    MapFragment  mMapFragment = MapFragment.newInstance();
     FragmentTransaction fragmentTransaction =
             getFragmentManager().beginTransaction();
     fragmentTransaction.add(R.id.container1, mMapFragment);
     fragmentTransaction.commit();

     if(mGoogleMap ==null){

            /*initializing map */

            mGoogleMap=mMapFragment.getMap();

            /*cretaing custom camera position*/

            CameraPosition mCameraPosition=new CameraPosition.Builder().target(SYDNEY).bearing(0).tilt(30).build();

            /*setting custom camera position*/

            mGoogleMap.animateCamera(CameraUpdateFactory.newCameraPosition(mCameraPosition));

            /*adding custom marker on the map.*/
             mGoogleMap.addMarker(new MarkerOptions().draggable(true).position(new LatLng(22.03, 72.56)).title("hello world").snippet("Ahmedabad").icon(BitmapDescriptorFactory.fromResource(R.drawable.wifi)));

            mGoogleMap.addMarker(new MarkerOptions().draggable(true).position(new LatLng(23.03, 78.10)).title("hello world").snippet("Baroda").icon(BitmapDescriptorFactory.fromResource(R.drawable.wifi)));

        }

        if(mGoogleMap !=null){


            /* map is already initialized then setting map type */
            /*
             * normal 
             * satellite
             * hybrid
             * terrain
             * none
             */
            mGoogleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);

        }

    return v;
}
}

03-01 12:15:31.439: E/AndroidRuntime(9299): FATAL EXCEPTION: main
03-01 12:15:31.439: E/AndroidRuntime(9299): java.lang.RuntimeException: Unable to start activity    ComponentInfo{com.tfick.android/com.tfick.android.PointOfIntrest}: java.lang.NullPointerException: CameraUpdateFactory is not initialized
03-01 12:15:31.439: E/AndroidRuntime(9299):     at    android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.ActivityThread.access$600(ActivityThread.java:140)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.os.Handler.dispatchMessage(Handler.java:99)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.os.Looper.loop(Looper.java:137)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at  android.app.ActivityThread.main(ActivityThread.java:4898)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at java.lang.reflect.Method.invokeNative(Native Method)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at java.lang.reflect.Method.invoke(Method.java:511)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1008)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:775)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at dalvik.system.NativeStart.main(Native Method)
03-01 12:15:31.439: E/AndroidRuntime(9299): Caused by: java.lang.NullPointerException: CameraUpdateFactory is not initialized
03-01 12:15:31.439: E/AndroidRuntime(9299):     at com.google.android.gms.internal.at.a(Unknown Source)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at com.google.android.gms.maps.CameraUpdateFactory.J(Unknown Source)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at com.google.android.gms.maps.CameraUpdateFactory.newCameraPosition(Unknown Source)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at com.tfick.fragment.PoiFragment.onCreateView(PoiFragment.java:51)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:829)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.BackStackRecord.run(BackStackRecord.java:635)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1397)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.Activity.performStart(Activity.java:5215)
03-01 12:15:31.439: E/AndroidRuntime(9299):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2073)
03-01 12:15:31.439: E/AndroidRuntime(9299):     ... 11 more

Answer 1

初始化CameraUpdateFactory。
根据文档 -
调用initialize(Context)。只要不抛出GooglePlayServicesNotAvailableException，此类就会被正确初始化。

链接 -
http://developer.android.com/reference/com/google/android/gms/maps/MapsInitializer.html#initialize(android.content.Context)
如何初始化 -

try {
     MapsInitializer.initialize(this /*the context*/);
 } catch (GooglePlayServicesNotAvailableException e) {
     e.printStackTrace();
 }

参考 - api v2 中的mapview和cameraupdate