在多个页面上显示查询结果

我正在尝试在多个页面上显示查询结果。当我尝试在每个页面上将查询结果显示为字符串时出现错误。

package com.example.cbtn;


public class StepsFragmentActivity extends FragmentActivity {


StepsPagerAdapter mStepsPagerAdapter;
DataBaseHelper myDataBase = new DataBaseHelper(this);
public static int pageCount;

/**
 * The {@link android.support.v4.view.ViewPager} that will display the
 * object collection.
 */
ViewPager mViewPager;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_collection_demo);

    // Create an adapter that when requested, will return a fragment
    // representing an object in
    // the collection.
    //
    // ViewPager and its adapters use support library fragments, so we must
    // use
    // getSupportFragmentManager.
    mStepsPagerAdapter = new StepsPagerAdapter(getSupportFragmentManager());
    // Set up action bar.
    final ActionBar actionBar = getActionBar();

    // Specify that the Home button should show an "Up" caret, indicating
    // that touching the
    // button will take the user one step up in the application's hierarchy.
    actionBar.setDisplayHomeAsUpEnabled(true);

    // Set up the ViewPager, attaching the adapter.
    mViewPager = (ViewPager) findViewById(R.id.pager);
    mViewPager.setAdapter(mStepsPagerAdapter);

    // Query on create to get the number of pages needed for a recipe
    String[] testarg = { "5" };
    Cursor results = myDataBase.queryDB(
            "SELECT s_step FROM Steps WHERE r_id = ?", testarg);
    pageCount = results.getCount();
    mStepsPagerAdapter.notifyDataSetChanged();
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
    case android.R.id.home:
        // This is called when the Home (Up) button is pressed in the action
        // bar.
        // Create a simple intent that starts the hierarchical parent
        // activity and
        // use NavUtils in the Support Package to ensure proper handling of
        // Up.
        Intent upIntent = new Intent(this, MainActivity.class);
        if (NavUtils.shouldUpRecreateTask(this, upIntent)) {
            // This activity is not part of the application's task, so
            // create a new task
            // with a synthesized back stack.
            TaskStackBuilder.from(this)
            // If there are ancestor activities, they should be added here.
                    .addNextIntent(upIntent).startActivities();
            finish();
        } else {
            // This activity is part of the application's task, so simply
            // navigate up to the hierarchical parent activity.
            NavUtils.navigateUpTo(this, upIntent);
        }
        return true;
    }
    return super.onOptionsItemSelected(item);
}

/**
 * A {@link android.support.v4.app.FragmentStatePagerAdapter} that returns a
 * fragment representing an object in the collection.
 */
public static class StepsPagerAdapter extends FragmentStatePagerAdapter {

    public StepsPagerAdapter(
            android.support.v4.app.FragmentManager fragmentManager) {
        super(fragmentManager);
    }

    @Override
    public Fragment getItem(int i) {
        // increment page object
        Fragment fragment = new StepsObjectFragment();
        Bundle args = new Bundle();
        args.putInt(StepsObjectFragment.ARG_OBJECT, i + 1);

        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public int getCount() {
        // Sets count to the number of query results
        // in the cursor
        return StepsFragmentActivity.pageCount;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return "Step " + (position + 1);
    }
}

/**
 * A dummy fragment representing a section of the app, but that simply
 * displays dummy text.
 */
public static class StepsObjectFragment extends Fragment {

    public static final String ARG_OBJECT = "object";

    DataBaseHelper myDataBase = new DataBaseHelper(getActivity());

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        // Query database
        String[] testarg = { "5" };
        Cursor results = myDataBase.queryDB(
                "SELECT s_step FROM Steps WHERE r_id = ?", testarg);

        View rootView = inflater.inflate(
                R.layout.fragment_collection_object, container, false);
        //Get position from pager adapter
        Bundle args = getArguments();
        int position = args.getInt(ARG_OBJECT);

        //Get the string from the cursor and set it to the page
        //This is where I crash
        String step = results.getString(position);
        ((TextView) rootView.findViewById(android.R.id.text1))
                .setText(step);
        return rootView;
    }
 }
}

我收到的错误告诉我我的应用程序无法读取第0行第1列。当我将step设置为restults.getString（0）时，这很奇怪。应用程序不会崩溃，但是其他任何数字或我的位置整数都会给我错误。

这是我的原木猫

05-30 18:36:01.872: E/CursorWindow(7771): Failed to read row 0, column 1 from a CursorWindow which has 5 rows, 1 columns.
05-30 18:36:01.872: W/dalvikvm(7771): threadid=1: thread exiting with uncaught exception (group=0x40bdd1f8)
05-30 18:36:01.892: E/AndroidRuntime(7771): FATAL EXCEPTION: main
05-30 18:36:01.892: E/AndroidRuntime(7771): java.lang.IllegalStateException: Couldn't read row 0, col 1 from CursorWindow.  Make sure the Cursor is initialized correctly before accessing data from it.
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.database.CursorWindow.nativeGetString(Native Method)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.database.CursorWindow.getString(CursorWindow.java:450)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:51)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at com.example.cbtn.StepsFragmentActivity$StepsObjectFragment.onCreateView(StepsFragmentActivity.java:178)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.app.Fragment.performCreateView(Fragment.java:1500)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:927)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1467)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:472)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:163)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.view.ViewPager.populate(ViewPager.java:1068)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.view.ViewPager.populate(ViewPager.java:914)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1436)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.View.measure(View.java:12929)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4703)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.View.measure(View.java:12929)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.widget.LinearLayout.measureVertical(LinearLayout.java:822)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.widget.LinearLayout.onMeasure(LinearLayout.java:563)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.View.measure(View.java:12929)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4703)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2257)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.View.measure(View.java:12929)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1240)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2628)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.os.Looper.loop(Looper.java:137)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at android.app.ActivityThread.main(ActivityThread.java:4511)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at java.lang.reflect.Method.invokeNative(Native Method)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at java.lang.reflect.Method.invoke(Method.java:511)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:976)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:743)
05-30 18:36:01.892: E/AndroidRuntime(7771):     at dalvik.system.NativeStart.main(Native Method)