应用程序恢复时无法启动活动ComponentInfo NullPointerException错误

Question

My application works fine but when it goes on background and then after resumes is stops working with these errors at logcat:

09-26 15:46:49.278: D/SqliteDatabaseCpp(5847): Registering sqlite logging func: /data/data/com.friends.roleon/databases/roleonDB
09-26 15:46:49.288: D/SqliteDatabaseCpp(5847): DB info: open db, path = /data/data/com.friends.roleon/databases , key = DvkadTace, flag = 6, file size = 34816
09-26 15:46:49.288: D/SqliteDatabaseCpp(5847): DB info: path = /data/data/com.friends.roleon/databases , key = DvkadTace, handle: 0x1f29030, type: w, r/w: (0,1), mode: truncate, disk free size: 213 M
09-26 15:46:49.318: D/SqliteDatabaseCpp(5847): DB info: close db, path = /data/data/com.friends.roleon/databases , key = DvkadTace, handle = 0x1f29030, type = w, r/w = (0, 0)
09-26 15:46:49.318: D/check(5847): create fragmentnull
09-26 15:46:49.559: D/SqliteDatabaseCpp(5847): DB info: open db, path = /data/data/com.friends.roleon/databases , key = DvkadTace, flag = 6, file size = 34816
09-26 15:46:49.599: D/SqliteDatabaseCpp(5847): DB info: path = /data/data/com.friends.roleon/databases , key = DvkadTace, handle: 0x1f4a208, type: w, r/w: (0,1), mode: truncate, disk free size: 213 M
09-26 15:46:49.649: D/SqliteDatabaseCpp(5847): DB info: open db, path = /data/data/com.friends.roleon/databases , key = DvkadTace, flag = 6, file size = 34816
09-26 15:46:49.649: D/AndroidRuntime(5847): Shutting down VM
09-26 15:46:49.649: W/dalvikvm(5847): threadid=1: thread exiting with uncaught exception (group=0x40aab228)
09-26 15:46:49.659: E/AndroidRuntime(5847): FATAL EXCEPTION: main
09-26 15:46:49.659: E/AndroidRuntime(5847): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.friends.roleon/com.friends.roleon.roleonMain}: java.lang.IllegalArgumentException: No view found for id 0x7f060038 for fragment RecordListFragment{40dd3b10 #2 id=0x7f060038}
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2205)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2240)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.ActivityThread.access$600(ActivityThread.java:139)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1262)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.os.Handler.dispatchMessage(Handler.java:99)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.os.Looper.loop(Looper.java:156)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.ActivityThread.main(ActivityThread.java:4987)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at java.lang.reflect.Method.invokeNative(Native Method)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at java.lang.reflect.Method.invoke(Method.java:511)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at dalvik.system.NativeStart.main(Native Method)
09-26 15:46:49.659: E/AndroidRuntime(5847): Caused by: java.lang.IllegalArgumentException: No view found for id 0x7f060038 for fragment RecordListFragment{40dd3b10 #2 id=0x7f060038}
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:864)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1080)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:622)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1416)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:505)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1195)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.Activity.performStart(Activity.java:4548)
09-26 15:46:49.659: E/AndroidRuntime(5847):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2178)
09-26 15:46:49.659: E/AndroidRuntime(5847):     ... 11 more
09-26 15:46:49.679: D/SqliteDatabaseCpp(5847): DB info: path = /data/data/com.friends.roleon/databases , key = DvkadTace, handle: 0x1f5d218, type: w, r/w: (0,2), mode: truncate, disk free size: 213 M
09-26 15:46:49.829: W/System.err(5847): java.lang.NullPointerException
09-26 15:46:49.829: W/System.err(5847):     at com.friends.roleon.utility.DataBase.<init>(DataBase.java:27)
09-26 15:46:49.839: W/System.err(5847):     at com.friends.roleon.list.ListViewGenerator.RecordViewGenerator(ListViewGenerator.java:25)
09-26 15:46:49.839: W/System.err(5847):     at com.friends.roleon.list.record.RecordList$RecordListFragment$BackgroundTask.doInBackground(RecordList.java:97)
09-26 15:46:49.839: W/System.err(5847):     at com.friends.roleon.list.record.RecordList$RecordListFragment$BackgroundTask.doInBackground(RecordList.java:1)
09-26 15:46:49.849: W/System.err(5847):     at android.os.AsyncTask$2.call(AsyncTask.java:264)
09-26 15:46:49.849: W/System.err(5847):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
09-26 15:46:49.849: W/System.err(5847):     at java.util.concurrent.FutureTask.run(FutureTask.java:137)
09-26 15:46:49.849: W/System.err(5847):     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
09-26 15:46:49.859: W/System.err(5847):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
09-26 15:46:49.859: W/System.err(5847):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
09-26 15:46:49.859: W/System.err(5847):     at java.lang.Thread.run(Thread.java:864)
09-26 15:46:49.869: D/error(5847): this is the exception :java.lang.NullPointerException
09-26 15:46:49.879: W/DBVersion(5847): 3
09-26 15:46:49.879: D/SqliteDatabaseCpp(5847): DB info: open db, path = /data/data/com.friends.roleon/databases , key = DvkadTace, flag = 6, file size = 34816
09-26 15:46:49.879: W/dalvikvm(5847): threadid=11: thread exiting with uncaught exception (group=0x40aab228)
09-26 15:46:49.879: D/SqliteDatabaseCpp(5847): DB info: path = /data/data/com.friends.roleon/databases , key = DvkadTace, handle: 0x1f77c90, type: w, r/w: (0,3), mode: truncate, disk free size: 213 M
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847): crash in the same process: AsyncTask #1
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847): java.lang.RuntimeException: An error occured while executing doInBackground()
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at android.os.AsyncTask$3.done(AsyncTask.java:278)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.util.concurrent.FutureTask.run(FutureTask.java:137)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.lang.Thread.run(Thread.java:864)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847): Caused by: java.lang.NullPointerException
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at com.friends.roleon.list.record.RecordList$RecordListFragment$BackgroundTask.doInBackground(RecordList.java:132)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at com.friends.roleon.list.record.RecordList$RecordListFragment$BackgroundTask.doInBackground(RecordList.java:1)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at android.os.AsyncTask$2.call(AsyncTask.java:264)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
09-26 15:46:49.889: E/AndroidRuntime_2_crash(5847):     ... 5 more
09-26 15:46:49.909: D/SqliteDatabaseCpp(5847): DB info: close db, path = /data/data/com.friends.roleon/databases , key = DvkadTace, handle = 0x1f77c90, type = w, r/w = (0, 2)

This is my main class:

public class roleon extends SherlockFragmentActivity implements
        ActionBar.TabListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        getSupportActionBar().setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
        getSupportActionBar().setDisplayShowHomeEnabled(false);
        getSupportActionBar().setDisplayShowTitleEnabled(false);

        AddTab(getString(R.string.tab_home));
        AddTab(getString(R.string.tab_activities));
        AddTab(getString(R.string.tab_settings));
    }

    private void AddTab(String tabName) {
        ActionBar.Tab tab = getSupportActionBar().newTab();
        tab.setText(tabName);
        tab.setTabListener(this);
        getSupportActionBar().addTab(tab);
    }

    @Override
    public void onTabSelected(Tab tab, FragmentTransaction ft) {
        Fragment fragment = null;
        if (tab.getText().equals(getText(R.string.tab_home))) {
            fragment = new ModuleList.ModuleListFragment();
        } else if (tab.getText().equals(getText(R.string.tab_activities))) {
            fragment = new ActivityStatePager.FragmentDisplay();
        } else if (tab.getText().equals(getText(R.string.tab_settings))) {
            fragment = new PreferenceScreen.PreferenceScreenFragment();
        }
        getSupportFragmentManager().beginTransaction()
                .replace(R.id.fragment_container, fragment).commit();
    }

    @Override
    public void onTabUnselected(Tab tab, FragmentTransaction ft) {
        // Do nothing
    }

    @Override
    public void onTabReselected(Tab tab, FragmentTransaction ft) {

    }
}

this is the fragment class from where the application crashes on resume:

public class ActivityStatePager extends SherlockFragmentActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        setTheme(R.style.Theme_Sherlock_NoActionBar);
        super.onCreate(savedInstanceState);

        if (savedInstanceState == null) {
            FragmentDisplay fragment = new FragmentDisplay();
            getSupportFragmentManager().beginTransaction()
                    .add(android.R.id.content, fragment).commit();
        }
    }

    @Override
    protected void onPause() {
        super.onPause();
         ActivityStatePager.this.finish();
    }

    @Override
    protected void onResume() {
        super.onResume();
        startActivity(new Intent(ActivityStatePager.this,
                roleon.class));
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        ActivityStatePager.this.finish();
    }

    public static class FragmentDisplay extends SherlockFragment {
        // Static Declarations
        static final int NUM_ITEMS = 3;

        private View mLayout;

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View v = inflater
                    .inflate(R.layout.fragment_pager, container, false);
            mLayout = v.findViewById(R.id.container);
            SetSpinner(v);
            return v;
        }

        @Override
        public void onActivityCreated(Bundle savedInstanceState) {
            super.onActivityCreated(savedInstanceState);
        }

        private void SetSpinner(View v) {
            Spinner eventspinner = (Spinner) v.findViewById(R.id.eventspinner);

            ArrayAdapter<CharSequence> adapter = new ArrayAdapter<CharSequence>(
                    getActivity(), android.R.layout.simple_spinner_item);
            adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

            DataBase db = new DataBase(getActivity(), "EventStatus");
            ArrayList<Record> eventsArray = db.SelectStatusList();
            db.close();

            for (Iterator<Record> iterator = eventsArray.iterator(); iterator
                    .hasNext();) {
                Record record = (Record) iterator.next();
                adapter.add(record.getEventStatus());
            }

            eventspinner.setAdapter(adapter);

            eventspinner
                    .setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
                        public void onItemSelected(AdapterView<?> parent,
                                View view, int pos, long id) {
                            CreateFragment(parent.getItemAtPosition(pos)
                                    .toString());
                        }

                        public void onNothingSelected(AdapterView<?> parent) {
                            // do nothing
                        }
                    });
        }

        public void CreateFragment(String fragLabel) {
            FragmentTransaction ft = getSherlockActivity()
                    .getSupportFragmentManager().beginTransaction();
            Fragment fragment = new ActivityListFragment(fragLabel);//fragLabel
            ft.add(((LinearLayout) mLayout).getId(), fragment).commit();
        }

        @Override
        public void onDestroyView() {
            super.onDestroyView();
        }

        public static class ActivityListFragment extends SherlockFragment {
            private String mFragTag;
            private View mFrameLayout;
            private View mView;

            public ActivityListFragment(String fragName) {
                mFragTag = fragName;
            }

            public ActivityListFragment(){
                // empty constructor
            }

            @Override
            public View onCreateView(LayoutInflater inflater,
                    ViewGroup container, Bundle savedInstanceState) {
                mView = inflater.inflate(R.layout.fragment_pager_list,
                        container, false);
                mFrameLayout = mView.findViewById(R.id.frame_layout);

                return mView;
            }

            public void onActivityCreated(Bundle savedInstanceState) {
                super.onActivityCreated(savedInstanceState);
                SetFragment();
            };

            public void SetFragment() {
                FragmentTransaction ft = getSherlockActivity()
                        .getSupportFragmentManager().beginTransaction();

                Fragment fragment = new RecordList.RecordListFragment();
                Bundle extras = new Bundle();
                extras.putString("eventstatus", mFragTag);
                fragment.setArguments(extras);

                ft.replace(((FrameLayout) mFrameLayout).getId(), fragment)
                        .commit();
            }

            @Override
            public void onDestroyView() {
                super.onDestroyView();
            }
        }
    }
}

R.id.frame_layout has the id: 0x7f060038 in R.java file

This is what my RecordList.RecordListFragment() do:

@Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            v = inflater.inflate(R.layout.record_list, container, false);
            mSP = PreferenceManager.getDefaultSharedPreferences(getActivity());
            GetIntent();
            getActivity().setTitle(label);
            new BackgroundTask().execute();
            return v;
        }


        private class BackgroundTask extends AsyncTask<Void, Void, Void> {
            ProgressDialog mDialog;

            protected void onPreExecute() {
                mDialog = ProgressDialog.show(getActivity(), "",
                        getString(R.string.progress_bar_loading), true);
            };

            @Override
            protected Void doInBackground(Void... params) {
                try {
                    mModule = new CRMModule(name, getActivity(),
                            getActivity().getIntent());
                    mEnableOptions = true;
                    rarray = ListViewGenerator.RecordViewGenerator(mSP,
                            getActivity(), name);
                    Log.d("values","in doinbackground"+mModule+","+rarray);
                    getActivity().runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            // Amazing List View
                            View composer = v.findViewById(R.id.lsComposer);
                            mLsComposer = ((DynamicListView) composer);
                            try {
                                mLsComposer
                                        .setAdapter(mAdapter = new PaginationComposerAdapter(
                                                mSP, getActivity(),
                                                rarray, name,
                                                label, mEventStatus));
                                Options(men);
                            } catch (Exception e) {
                                Log.d("exception", "this is here at composer"+e);
                                e.printStackTrace();
                            }
                            if (mAdapter.getCount() > 10) {
                                mLsComposer
                                        .setLoadingView(getActivity()
                                                .getLayoutInflater()
                                                .inflate(
                                                        R.layout.lscomposer_loadingview,
                                                        null));
                            }
                            Log.d("complete","at the end");

                        }

                    });
                } catch (final Exception e) {
                    Log.d("error", "this is the exception :"+e);
                    getActivity().runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            mEnableOptions = false;
                            // getActivity().supportInvalidateOptionsMenu();
                            MethodActivity.CheckLogin(mSP, getActivity()
                                    .getIntent(), getActivity(), e);
                        }
                    });
                }
                return null;
            }

            protected void onPostExecute(Void result) {
                mDialog.dismiss();
            };
        };

help to sort our this problem. thanks in advance.

Answer 1

You should not call finish() on onDestroy() since onDestroy() is triggered when someone already called finish() look at the android documentation . Same thing with calling finish() on the onPause() event, if what you are trying to achieve is to detach your FragmentDisplay from ActivityStatePager you should move

if (savedInstanceState == null) {
        FragmentDisplay fragment = new FragmentDisplay();
        getSupportFragmentManager().beginTransaction()
                .add(android.R.id.content, fragment).commit();
    }

into the onResume() event and detach this fragment on the onPause() event. With your code you are forcing the call onCreate() each time the activity gets paused which is a expesive operation.

I think the exception java.lang.IllegalArgumentException: No view found for id 0x7f060038 comes from the way your activity is doing it's onResume() .

Also can you show what RecordList.RecordListFragment.BackgroundTask does? The NullPointerException starts there.

Edit after RecordList.RecordListFragment.BackgroundTask code was added:

Ok i think i got this. Avoid accessing the UIThread while doing on doInBackground(). Use AsyncTask.publishProgress() and override AsyncTask.onProgressUpdate() to make changes to the UI while there's still work to do on the background thread (look at the documentation on AsynTask ). In your case scenario you should put

                        View composer = v.findViewById(R.id.lsComposer);
                        mLsComposer = ((DynamicListView) composer);
                        try {
                            mLsComposer
                                    .setAdapter(mAdapter = new PaginationComposerAdapter(
                                            mSP, getActivity(),
                                            rarray, name,
                                            label, mEventStatus));
                            Options(men);
                        } catch (Exception e) {
                            Log.d("exception", "this is here at composer"+e);
                            e.printStackTrace();
                        }
                        if (mAdapter.getCount() > 10) {
                            mLsComposer
                                    .setLoadingView(getActivity()
                                            .getLayoutInflater()
                                            .inflate(
                                                    R.layout.lscomposer_loadingview,
                                                    null));
                        }
                        Log.d("complete","at the end");

onPostExecute() since you want to make changes to your UI after the long work is done.