4
我想在我的代碼中將SupportMapFragment添加到FrameLayout中，但我得到了空指針執行。Android SupportMapFragment無法看到片段內的地圖
我的代碼：
MainFragment：
public class MainFragment extends FragmentActivity{
@Override
protected void onCreate(Bundle arg0) {
super.onCreate(arg0);
setContentView(R.layout.activity_main);
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft = getSupportFragmentManager().beginTransaction();
SecondFragment second = new SecondFragment();
ft.add(R.main_activity.frame, second);
ft.addToBackStack(null);
ft.commit();
}
}
SecondFragment：
public class SecondFragment extends SupportMapFragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.activity_map, null);
}
}
我的XML：
activity_main：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<include
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
layout="@layout/header" />
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="7.06"
android:id="@+main_activity/frame"
android:background="@drawable/defaultbg"/>
<include
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_gravity="bottom"
android:layout_weight="1"
layout="@layout/footer" />
</LinearLayout>
activity_map：
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<fragment
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.google.android.gms.maps.SupportMapFragment"/>
</FrameLayout>
我的logcat：
03-07 21:20:17.160: E/AndroidRuntime(1617): FATAL EXCEPTION: main
03-07 21:20:17.160: E/AndroidRuntime(1617): java.lang.RuntimeException: Unable to resume activity {com.WhosAround/com.WhosAround.MainFragment}: java.lang.NullPointerException
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2124)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2139)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1672)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.os.Handler.dispatchMessage(Handler.java:99)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.os.Looper.loop(Looper.java:130)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.ActivityThread.main(ActivityThread.java:3691)
03-07 21:20:17.160: E/AndroidRuntime(1617): at java.lang.reflect.Method.invokeNative(Native Method)
03-07 21:20:17.160: E/AndroidRuntime(1617): at java.lang.reflect.Method.invoke(Method.java:507)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:665)
03-07 21:20:17.160: E/AndroidRuntime(1617): at dalvik.system.NativeStart.main(Native Method)
03-07 21:20:17.160: E/AndroidRuntime(1617): Caused by: java.lang.NullPointerException
03-07 21:20:17.160: E/AndroidRuntime(1617): at maps.z.r.onResume(Unknown Source)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.google.android.gms.maps.internal.IMapFragmentDelegate$Stub.onTransact(IMapFragmentDelegate.java:115)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.os.Binder.transact(Binder.java:279)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.google.android.gms.maps.internal.IMapFragmentDelegate$a$a.onResume(Unknown Source)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.google.android.gms.maps.SupportMapFragment$a.onResume(Unknown Source)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.google.android.gms.internal.e$1.a(Unknown Source)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.google.android.gms.internal.e.a(Unknown Source)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.google.android.gms.internal.e.onResume(Unknown Source)
03-07 21:20:17.160: E/AndroidRuntime(1617): at com.google.android.gms.maps.SupportMapFragment.onResume(Unknown Source)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.support.v4.app.Fragment.performResume(Fragment.java:1503)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:947)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1070)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.support.v4.app.FragmentManagerImpl.dispatchResume(FragmentManager.java:1871)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.support.v4.app.FragmentActivity.onResumeFragments(FragmentActivity.java:455)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.support.v4.app.FragmentActivity.onPostResume(FragmentActivity.java:444)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.Activity.performResume(Activity.java:3867)
03-07 21:20:17.160: E/AndroidRuntime(1617): at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2114)
03-07 21:20:17.160: E/AndroidRuntime(1617): ... 12 more
不相關，但不需要調用'beginTransaction'兩次。你可以從MainFragment.java中移除這一行'ft = getSupportFragmentManager（）。beginTransaction（）;' – MCeley 2013-03-07 19:43:54
是啊，你寫的是因爲我在粘貼代碼後刪除了一些行 – 2013-03-07 19:50:43