Question

我正在尝试给微调器充气，并且强制关闭我的应用程序时出现此错误：

java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.mike.beerportfoliomaterial/com.example.mike.beerportfoliomaterial.MainDrawer2}: java.lang.NullPointerException
       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java)
       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java)
       at android.app.ActivityThread.access$800(ActivityThread.java)
       at android.app.ActivityThread$H.handleMessage(ActivityThread.java)
       at android.os.Handler.dispatchMessage(Handler.java)
       at android.os.Looper.loop(Looper.java)
       at android.app.ActivityThread.main(ActivityThread.java)
       at java.lang.reflect.Method.invokeNative(Method.java)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java)
       at dalvik.system.NativeStart.main(NativeStart.java)
Caused by: java.lang.NullPointerException
       at com.example.mike.beerportfoliomaterial.StatisticsPage.onCreateView(StatisticsPage.java:35)
       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.FragmentActivity.onStart(FragmentActivity.java:548)
       at android.app.Instrumentation.callActivityOnStart(Instrumentation.java)
       at android.app.Activity.performStart(Activity.java)
       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java)
       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java)
       at android.app.ActivityThread.access$800(ActivityThread.java)
       at android.app.ActivityThread$H.handleMessage(ActivityThread.java)
       at android.os.Handler.dispatchMessage(Handler.java)
       at android.os.Looper.loop(Looper.java)
       at android.app.ActivityThread.main(ActivityThread.java)
       at java.lang.reflect.Method.invokeNative(Method.java)
       at java.lang.reflect.Method.invoke(Method.java)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java)
       at dalvik.system.NativeStart.main(NativeStart.java)

我的StatisticsPage.java是：

import android.app.ActionBar;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTabHost;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.ActionBarActivity;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;

/**
 * Created by Mike on 2/13/14.
 */
public class StatisticsPage extends Fragment  {

    public StatisticsPage(){}
    private FragmentTabHost mTabHost;



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

        Spinner spinner = (Spinner) getView().findViewById(R.id.statsSpin);
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(getActivity(),
                R.array.statspage, android.R.layout.simple_spinner_item);


        View rootView = inflater.inflate(R.layout.statistics_pagelayout, container, false);


        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getActivity());
        String userName = prefs.getString("userName", null);
        String userID = prefs.getString("userID", null);
        String url = "myURL";
        String userURLComp = "u=" + userID;


        url = url + userURLComp ;



        new getBasicStats(getActivity()).execute(url);




        return rootView;
    }





}

第35行是：

    Spinner spinner = (Spinner) getView().findViewById(R.id.statsSpin);

我尝试将微调器代码移动到视图根视图行之后但没有骰子。

Answer 1

尝试

Spinner spinner = (Spinner) rootView.findViewById(R.id.statsSpin);

分配后

膨胀微调器是强制关闭我的应用程序

1 个答案: