我正在尝试在片段中加载Google地图，无论我尝试实施什么解决方案，我都会遇到同样的错误。我已经完成了所有类似的（如果不是相同的）问题，并试图做出前几个最佳答案所提出的建议，但遗憾的是没有运气。如果你能帮助我，我真的很感激：
我的MainActivity.java如下：
package com.nzf.nzf.nzfmap;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.support.v4.app.*;
import android.support.v4.view.ViewPager;
import android.util.Log;
import java.util.List;
import java.util.Vector;
/**
* Created by Adil on 21/04/2015.
*/
public class MainActivity extends FragmentActivity {
private PagerAdapter mPagerAdapter;
public static FragmentManager fragmentManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
Log.d("Position", "I am in MainActivity");
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// initialising the object of the FragmentManager.
fragmentManager = getSupportFragmentManager();
initialisePaging();
}
private void initialisePaging() {
List<Fragment> fragments = new Vector<Fragment>();
fragments.add(new ListFragment());
fragments.add(new MapsFragment());
ViewPager pager = (ViewPager) findViewById(R.id.viewpager);
mPagerAdapter = new PagerAdapter(getSupportFragmentManager(),fragments);
pager.setAdapter(mPagerAdapter);
}
}
我在Fragments列表中添加了两个片段
1. ListFragment我对这个片段没有任何问题。
2. MapsFragment我主要担心的是这个片段。
这是我的MapsFragment.java内容：
package com.nzf.nzf.nzfmap;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.RelativeLayout;
import com.google.android.gms.maps.GoogleMap;
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.MarkerOptions;
public class MapsFragment extends Fragment {
static final LatLng MELBOURNE = new LatLng(-37.8254,144.95410);
static final LatLng SYDNEY = new LatLng(-33.86916,151.20437);
private GoogleMap mMap; // Might be null if Google Play services APK is not available.
public MapsFragment() {
// Required empty public constructor
}
@Override
public void onResume() {
super.onResume();
setUpMapIfNeeded();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
Log.d("Position", "I am in MapsFragment");
if (container == null) {
return null;
}
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_map, container, false);
setUpMapIfNeeded();
return view;
}
/**
* Sets up the map if it is possible to do so (i.e., the Google Play services APK is correctly
* installed) and the map has not already been instantiated.. This will ensure that we only ever
* call {@link #setUpMap()} once when {@link #mMap} is not null.
* <p/>
* If it isn't installed {@link SupportMapFragment} (and
* {@link com.google.android.gms.maps.MapView MapView}) will show a prompt for the user to
* install/update the Google Play services APK on their device.
* <p/>
* A user can return to this FragmentActivity after following the prompt and correctly
* installing/updating/enabling the Google Play services. Since the FragmentActivity may not
* have been completely destroyed during this process (it is likely that it would only be
* stopped or paused), {@link #onCreate(Bundle)} may not be called again so we should call this
* method in {@link #onResume()} to guarantee that it will be called.
*/
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)getFragmentManager().findFragmentById(R.id.map))
.getMap();
// Check if we were successful in obtaining the map.
if (mMap != null) {
setUpMap();
}
}
}
/**
* This is where we can add markers or lines, add listeners or move the camera. In this case, we
* just add a marker near Africa.
* <p/>
* This should only be called once and when we are sure that {@link #mMap} is not null.
*/
private void setUpMap() {
mMap.addMarker(new MarkerOptions().position(MELBOURNE).title("mMarker"));
MarkerOptions mo = new MarkerOptions();
mo.draggable(true);
mo.position(SYDNEY).title("sMarker");
mo.icon(BitmapDescriptorFactory.fromResource(R.drawable.ic_launcher));
mMap.addMarker(mo);
Log.d(Constants.LOG, "on setUpMap");
}
public interface Constants {
String LOG = "com.nzf.nzf.nzfmap";
}
}
上述片段的Xml文件（fragment_map.xml）如下：
<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="com.nzf.nzf.nzfmap.MapsFragment">
<fragment
android:id="@+id/map"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.google.android.gms.maps.SupportMapFragment" />
</RelativeLayout>
我在logcat中得到的错误如下：
07-04 21:32:37.455 7623-7623/com.example.nzf.nzfmap D/Position﹕ I am in MainActivity
07-04 21:32:37.530 7623-7623/com.example.nzf.nzfmap D/dalvikvm﹕ GC_FOR_ALLOC freed 103K, 17% free 10022K/12000K, paused 23ms, total 23ms
07-04 21:32:37.535 7623-7623/com.example.nzf.nzfmap I/dalvikvm-heap﹕ Grow heap (frag case) to 12.689MB for 1127536-byte allocation
07-04 21:32:37.565 7623-7632/com.example.nzf.nzfmap D/dalvikvm﹕ GC_FOR_ALLOC freed <1K, 16% free 11123K/13104K, paused 24ms, total 24ms
07-04 21:32:37.615 7623-7623/com.example.nzf.nzfmap D/Position﹕ I am in ListFragment
07-04 21:32:37.615 7623-7623/com.example.nzf.nzfmap D/Position﹕ I am in MapsFragment
07-04 21:32:37.630 7623-7623/com.example.nzf.nzfmap I/x﹕ Making Creator dynamically
07-04 21:32:37.650 7623-7623/com.example.nzf.nzfmap I/Google Maps Android API﹕ Google Play services client version: 6587000
07-04 21:32:37.655 7623-7623/com.example.nzf.nzfmap I/Google Maps Android API﹕ Google Play services package version: 7574036
07-04 21:32:37.675 7623-7623/com.example.nzf.nzfmap I/dalvikvm﹕ Could not find method android.app.AppOpsManager.checkPackage, referenced from method com.google.android.gms.common.ij.a
07-04 21:32:37.675 7623-7623/com.example.nzf.nzfmap W/dalvikvm﹕ VFY: unable to resolve virtual method 111: Landroid/app/AppOpsManager;.checkPackage (ILjava/lang/String;)V
07-04 21:32:37.675 7623-7623/com.example.nzf.nzfmap D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0012
07-04 21:32:37.675 7623-7623/com.example.nzf.nzfmap I/dalvikvm﹕ Could not find method android.content.pm.PackageManager.getPackageInstaller, referenced from method com.google.android.gms.common.ij.a
07-04 21:32:37.675 7623-7623/com.example.nzf.nzfmap W/dalvikvm﹕ VFY: unable to resolve virtual method 449: Landroid/content/pm/PackageManager;.getPackageInstaller ()Landroid/content/pm/PackageInstaller;
07-04 21:32:37.680 7623-7623/com.example.nzf.nzfmap D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x000d
07-04 21:32:37.685 7623-7623/com.example.nzf.nzfmap I/dalvikvm﹕ Could not find method android.app.Notification$Builder.setLocalOnly, referenced from method com.google.android.gms.common.ij.b
07-04 21:32:37.685 7623-7623/com.example.nzf.nzfmap W/dalvikvm﹕ VFY: unable to resolve virtual method 154: Landroid/app/Notification$Builder;.setLocalOnly (Z)Landroid/app/Notification$Builder;
07-04 21:32:37.685 7623-7623/com.example.nzf.nzfmap D/dalvikvm﹕ VFY: replacing opcode 0x6e at 0x0201
07-04 21:32:37.895 7623-7623/com.example.nzf.nzfmap D/AbsListView﹕ Get MotionRecognitionManager
07-04 21:32:37.900 7623-7623/com.example.nzf.nzfmap D/AbsListView﹕ onVisibilityChanged() is called, visibility : 8
07-04 21:32:37.900 7623-7623/com.example.nzf.nzfmap D/AbsListView﹕ unregisterIRListener() is called
07-04 21:32:37.905 7623-7623/com.example.nzf.nzfmap D/AbsListView﹕ onVisibilityChanged() is called, visibility : 8
07-04 21:32:37.905 7623-7623/com.example.nzf.nzfmap D/AbsListView﹕ unregisterIRListener() is called
07-04 21:32:37.975 7623-7668/com.example.nzf.nzfmap D/dalvikvm﹕ GC_FOR_ALLOC freed 558K, 17% free 12102K/14532K, paused 31ms, total 31ms
07-04 21:32:38.080 7623-7623/com.example.nzf.nzfmap D/AbsListView﹕ onVisibilityChanged() is called, visibility : 0
07-04 21:32:38.080 7623-7623/com.example.nzf.nzfmap D/AbsListView﹕ unregisterIRListener() is called
07-04 21:32:38.110 7623-7623/com.example.nzf.nzfmap D/AndroidRuntime﹕ Shutting down VM
07-04 21:32:38.110 7623-7623/com.example.nzf.nzfmap W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x41bae700)
07-04 21:32:38.115 7623-7623/com.example.nzf.nzfmap E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NullPointerException
at com.nzf.nzf.nzfmap.MapsFragment.setUpMapIfNeeded(MapsFragment.java:66)
at com.nzf.nzf.nzfmap.MapsFragment.onCreateView(MapsFragment.java:43)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1786)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:947)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1126)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:739)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1489)
at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:486)
at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1073)
at android.support.v4.view.ViewPager.populate(ViewPager.java:919)
at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1441)
at android.view.View.measure(View.java:16831)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5245)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1410)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
at android.view.View.measure(View.java:16831)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5245)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.view.View.measure(View.java:16831)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5245)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1410)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
at android.view.View.measure(View.java:16831)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5245)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2586)
at android.view.View.measure(View.java:16831)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2189)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1352)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1535)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1249)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6364)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:791)
at android.view.Choreographer.doCallbacks(Choreographer.java:591)
at android.view.Choreographer.doFrame(Choreographer.java:561)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:777)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1209)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1025)
at dalvik.system.NativeStart.main(Native Method)
编辑1：这是我的AndroidManifest.xml文件：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.nzf.nzf.nzfmap" >
<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" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<!--
The ACCESS_COARSE/FINE_LOCATION 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" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<meta-data
android:name="com.google.android.maps.v2.API_KEY"
android:value="@string/google_maps_key" />
<activity
android:name="com.nzf.nzf.nzfmap.MainActivity"
android:label="@string/title_activity_maps" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
答案 0 :(得分：1)
您的MapsFragment第66行，替换：
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment)getFragmentManager().findFragmentById(R.id.map))
.getMap();
由：
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment)getChildFragmentManager().findFragmentById(R.id.map))
.getMap();
因为您的地图片段是片段中的片段，而不是由顶级FragmentManager管理。
此外，我不确定，但您可能想要异步设置地图：
((SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map)).getMapAsync(
new OnMapReadyCallback() {
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
setUpMap();
}
});
答案 1 :(得分：0)
You can do this as a normal fragment.
public void replaceFragment(Fragment fragment, String fragmentTag){
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
fragmentTransaction.replace(R.id.container, fragment);
fragmentTransaction.addToBackStack(fragmentTag);
fragmentTransaction.commit();
}
private void initMap(){
MapFragment mapFragment = MapFragment.newInstance();
replaceFragment(mapFragment, fragmentTag);
mapFragment.getMapAsync(this);
}