我正在尝试从活动中加载片段，并收到如下错误：
07-25 21:09:53.221 31245-31245/kitchenpal.troychuinard.com.kitchenpal E/AndroidRuntime: FATAL EXCEPTION: main
Process: kitchenpal.troychuinard.com.kitchenpal, PID: 31245
java.lang.RuntimeException: Unable to start activity ComponentInfo{kitchenpal.troychuinard.com.kitchenpal/kitchenpal.troychuinard.com.kitchenpal.IndividualRecipeActivity}: android.view.InflateException: Binary XML file line #9: Binary XML file line #9: Error inflating class fragment
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Caused by: android.view.InflateException: Binary XML file line #9: Binary XML file line #9: Error inflating class fragment
Caused by: android.view.InflateException: Binary XML file line #9: Error inflating class fragment
Caused by: java.lang.NullPointerException
at java.lang.VMClassLoader.findLoadedClass(Native Method)
at java.lang.ClassLoader.findLoadedClass(ClassLoader.java:742)
at java.lang.ClassLoader.loadClass(ClassLoader.java:362)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at android.support.v4.app.Fragment.isSupportFragmentClass(Fragment.java:404)
at android.support.v4.app.FragmentManagerImpl.onCreateView(FragmentManager.java:3679)
at android.support.v4.app.FragmentController.onCreateView(FragmentController.java:114)
at android.support.v4.app.FragmentActivity.dispatchFragmentsOnCreateView(FragmentActivity.java:374)
at android.support.v4.app.BaseFragmentActivityApi14.onCreateView(BaseFragmentActivityApi14.java:39)
at android.support.v4.app.FragmentActivity.onCreateView(FragmentActivity.java:68)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:777)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:727)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:858)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:821)
at android.view.LayoutInflater.inflate(LayoutInflater.java:518)
at android.view.LayoutInflater.inflate(LayoutInflater.java:426)
at android.view.LayoutInflater.inflate(LayoutInflater.java:377)
at com.android.internal.policy.PhoneWindow.setContentView(PhoneWindow.java:412)
at android.app.Activity.setContentView(Activity.java:2414)
at kitchenpal.troychuinard.com.kitchenpal.IndividualRecipeActivity.onCreate(IndividualRecipeActivity.java:15)
我了解这可能与我用于片段管理器的支持库有关。
public class IndividualRecipeActivity extends AppCompatActivity implements RecipeStepsFragment.OnFragmentInteractionListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_individual_recipe);
if (savedInstanceState == null){
RecipeStepsFragment recipeStepsFragment = new RecipeStepsFragment();
FragmentManager fm = getSupportFragmentManager();
fm.beginTransaction()
.add(R.id.recipe_list_fragment, recipeStepsFragment)
.commit();
}
}
@Override
public void onFragmentInteraction(Uri uri) {
}
}
片段：
public class RecipeStepsFragment extends Fragment {
// TODO: Rename parameter arguments, choose names that match
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
// TODO: Rename and change types of parameters
private String mParam1;
private String mParam2;
private OnFragmentInteractionListener mListener;
public RecipeStepsFragment() {
// Required empty public constructor
}
/**
* Use this factory method to create a new instance of
* this fragment using the provided parameters.
*
* @param param1 Parameter 1.
* @param param2 Parameter 2.
* @return A new instance of fragment RecipeStepsFragment.
*/
// TODO: Rename and change types and number of parameters
public static RecipeStepsFragment newInstance(String param1, String param2) {
RecipeStepsFragment fragment = new RecipeStepsFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_recipe_steps, container, false);
}
// TODO: Rename method, update argument and hook method into UI event
public void onButtonPressed(Uri uri) {
if (mListener != null) {
mListener.onFragmentInteraction(uri);
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
/**
* This interface must be implemented by activities that contain this
* fragment to allow an interaction in this fragment to be communicated
* to the activity and potentially other fragments contained in that
* activity.
* <p>
* See the Android Training lesson <a href=
* "http://developer.android.com/training/basics/fragments/communicating.html"
* >Communicating with Other Fragments</a> for more information.
*/
public interface OnFragmentInteractionListener {
// TODO: Update argument type and name
void onFragmentInteraction(Uri uri);
}
}
XML：
<?xml version="1.0" encoding="utf-8"?>
<fragment
android:id="@+id/recipe_list_fragment"
android:layout_width="match_parent"
android:layout_height="match_parent">
</fragment>