android - 在 fragment 中使用 MaterialViewPager 库时出错

Question

我正在使用这个库:https://github.com/florent37/MaterialViewPager

我有一个 Navigation Drawer ，如果我点击 navdrawer 列表中的其中一项，Material View Pager 就会加载。 (替换 fragment )。

但是我在那里得到了这个错误:(

        Recursive entry to executePendingTransactions
        at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1534)
        at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:535)
        at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:163)
        at android.support.v4.view.ViewPager.populate(ViewPager.java:1106)
        at android.support.v4.view.ViewPager.populate(ViewPager.java:952)
        at android.support.v4.view.ViewPager.setOffscreenPageLimit(ViewPager.java:733)
        at razor.nikhil.mvp.MaterialVPFrag.onViewCreated(MaterialVPFrag.java:130)
        at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1035)
        at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1197)
        at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:738)
        at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1562)
        at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:483)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5254)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at  com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)


)

在这一行:

  mViewPager.getViewPager().setOffscreenPageLimit(mViewPager.getViewPager().getAdapter().getCount());

如果我删除该行它会起作用(但这会在将来给我一个错误吗？)当我浏览选项卡时，有时会出现此错误。(

   java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid view holder adapter positionViewHolder{26fe4ecd position=6 id=-1, oldPos=-1, pLpos:-1 no parent}
    at android.support.v7.widget.RecyclerView$Recycler.validateViewHolderForOffsetPosition(RecyclerView.java:4349)
    at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4480)
    at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4461)
    at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:1962)
    at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1371)
    at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1334)
    at android.support.v7.widget.LinearLayoutManager.scrollBy(LinearLayoutManager.java:1162)
    at android.support.v7.widget.LinearLayoutManager.scrollVerticallyBy(LinearLayoutManager.java:1019)
    at android.support.v7.widget.RecyclerView$ViewFlinger.run(RecyclerView.java:3912)
    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
    at android.view.Choreographer.doCallbacks(Choreographer.java:580)
    at android.view.Choreographer.doFrame(Choreographer.java:549)
    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
    at android.os.Handler.handleCallback(Handler.java:739)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:135)
    at android.app.ActivityThread.main(ActivityThread.java:5254)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)   )

这个错误是因为那一行吗？

MaterialVPFrag.java(带有 materialviewpager 的 fragment )

public class MaterialVPFrag extends Fragment {
private MaterialViewPager mViewPager;
List<Model_Daywise> todayslist_m;
List<Model_Daywise> todayslist_t;
List<Model_Daywise> todayslist_w;
List<Model_Daywise> todayslist_th;
List<Model_Daywise> todayslist_fr;

public static MaterialVPFrag newInstance() {
    return new MaterialVPFrag();
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    return inflater.inflate(R.layout.mvp_layout, container, false);
}

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    todayslist_m = new MTWTHgetset(getActivity(), "monday").getAllCredentials();//getting data from SQL
    todayslist_t = new MTWTHgetset(getActivity(), "tuesday").getAllCredentials();
    todayslist_w = new MTWTHgetset(getActivity(), "wednesday").getAllCredentials();
    todayslist_th = new MTWTHgetset(getActivity(), "thursday").getAllCredentials();
    todayslist_fr = new MTWTHgetset(getActivity(), "friday").getAllCredentials();
    mViewPager = (MaterialViewPager) view.findViewById(R.id.materialViewPager);
    mViewPager.getViewPager().setAdapter(new FragmentStatePagerAdapter(getActivity().getSupportFragmentManager()) {

        @Override
        public Fragment getItem(int position) {
            switch (position) {
                case 0:
                    return RecyclerViewFragment.newInstance(todayslist_m);
                case 1:
                    return RecyclerViewFragment.newInstance(todayslist_t);
                case 2:
                    return RecyclerViewFragment.newInstance(todayslist_w);
                case 3:
                    return RecyclerViewFragment.newInstance(todayslist_th);
                case 4:
                    return RecyclerViewFragment.newInstance(todayslist_fr);
                // return WebViewFragment.newInstance();
                default:
                    return RecyclerViewFragment.newInstance(todayslist_m);
            }
        }

        @Override
        public int getCount() {
            return 5;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            switch (position) {
                case 0:
                    return "Monday";
                case 1:
                    return "Tuesday";
                case 2:
                    return "Wednesday";
                case 3:
                    return "Thursday";
                case 4:
                    return "Friday";
            }
            return "";
        }
    });
    mViewPager.setMaterialViewPagerListener(new MaterialViewPager.Listener() {
        @Override
        public HeaderDesign getHeaderDesign(int page) {
            switch (page) {
                case 0:
                    return HeaderDesign.fromColorResAndUrl(
                            R.color.green,
                            "https://fs01.androidpit.info/a/63/0e/android-l-wallpapers-630ea6-h900.jpg");
                case 1:
                    return HeaderDesign.fromColorResAndUrl(
                            R.color.blue,
                            "http://cdn1.tnwcdn.com/wp-content/blogs.dir/1/files/2014/06/wallpaper_51.jpg");
                case 2:
                    return HeaderDesign.fromColorResAndUrl(
                            R.color.cyan,
                            "http://www.droid-life.com/wp-content/uploads/2014/10/lollipop-wallpapers10.jpg");
                case 3:
                    return HeaderDesign.fromColorResAndUrl(
                            R.color.red,
                            "http://www.tothemobile.com/wp-content/uploads/2014/07/original.jpg");
            }

            //execute others actions if needed (ex : modify your header logo)

            return null;
        }
    });

      mViewPager.getViewPager().setOffscreenPageLimit(mViewPager.getViewPager().getAdapter().getCount());
    mViewPager.getPagerTitleStrip().setViewPager(mViewPager.getViewPager());

    View logo = view.findViewById(R.id.logo_white);
    if (logo != null)
        logo.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                mViewPager.notifyHeaderChanged();
                Toast.makeText(getActivity(), "Yes, the title is clickable", Toast.LENGTH_SHORT).show();
            }
        });

}
}

DrawerActivity.java(带有 NavDrawer 的类)

  public class DrawerActivity extends ActionBarActivity {

Toolbar t;
private DrawerLayout mDrawerLayout;
private ListView mDrawerList;
private RelativeLayout mRelativeLayout;
private ActionBarDrawerToggle mDrawerToggle;
static List<Model_Slots> list;
private CharSequence mDrawerTitle, mTitle;
private String[] navMenuItems;
private SpannableString[] navmenuItems;
private ArrayAdapter<SpannableString> adapter;

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

    try {
        list = new Slots_GetSet(this).getAllCredentials();
    } catch (Exception e) {
        e.printStackTrace();
    }
    initStuffs();
    if (savedInstanceState == null) {
        new SliderMenuClickListener().displayView(0);
    }

}


private void initStuffs() {
    mTitle = mDrawerTitle = getTitle();
    navMenuItems = getResources().getStringArray(R.array.Titles);
    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    mDrawerList = (ListView) findViewById(R.id.list_slidermenu);
    mRelativeLayout = (RelativeLayout) findViewById(R.id.rel_drawer);

    navmenuItems = new SpannableString[navMenuItems.length];
    for (int i = 0; i < navMenuItems.length; i++) {
        navmenuItems[i] = new SpannableString(Html.fromHtml("<font color='#000000'>" + navMenuItems[i] + "</font>"));
    }
    adapter = new ArrayAdapter<SpannableString>(DrawerActivity.this, android.R.layout.simple_list_item_1, navmenuItems);
    mDrawerList.setAdapter(adapter);

    mDrawerToggle = new ActionBarDrawerToggle(DrawerActivity.this, mDrawerLayout, t, R.string.app_name, R.string.app_name) {
        public void onDrawerClosed(View view) {
            invalidateOptionsMenu();
        }

        public void onDrawerOpened(View view) {
            invalidateOptionsMenu();
        }
    };
    mDrawerLayout.setDrawerListener(mDrawerToggle);
    mDrawerList.setOnItemClickListener(new SliderMenuClickListener());
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.drawer, menu);
    return true;
}

@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    boolean drawerOpen = mDrawerLayout.isDrawerOpen(mRelativeLayout);
    menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
    return super.onPrepareOptionsMenu(menu);
}

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    mDrawerToggle.onConfigurationChanged(newConfig);
}

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    mDrawerToggle.syncState();
}

@Override
public void setTitle(CharSequence title) {
    super.setTitle(title);
    mTitle = title;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if (mDrawerToggle.onOptionsItemSelected(item)) {
        return true;
    }
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

private class SliderMenuClickListener implements ListView.OnItemClickListener {

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        displayView(position);
    }

    private void displayView(int position) {
        Fragment fragment = null;
        switch (position) {
            case 0:
                String s = getSharedPreferences("Apple", Context.MODE_PRIVATE).getString("slots_down", "no");
                if (s.equals("already")) {
                    fragment = new Fragment_slots(list);
                } else if (s.equals("yes")) {
                    list = new Slots_GetSet(getApplicationContext()).getAllCredentials();
                    fragment = new Fragment_slots(list);
                } else if (s.equals("no")) {
                    fragment = new HomeFragment();
                }
                break;
            case 1:
                fragment = new Photo_StudentLogin();
                break;
            case 2:
                fragment = new HomeFragment();
                break;
            case 3:
                fragment = MaterialVPFrag.newInstance();
                break;
            default:
                fragment = new HomeFragment();
                break;
        }
        if (fragment != null) {
            FragmentManager fm = getSupportFragmentManager();
            fm.beginTransaction().replace(R.id.frame_container, fragment).commit();
            mDrawerList.setItemChecked(position, true);
            mDrawerList.setSelection(position);
            mDrawerLayout.closeDrawer(mRelativeLayout);
        } else {
            Log.e("DrawerActivity", "Error creating fragment");
        }
    }

}
 }

谢谢!

Answer 1

您使用的示例使用了一个 Activity 。您正在使用 fragment ，这意味着您有嵌套 fragment 。

因此您需要使用子 fragment 管理器而不是支持 fragment 管理器。所以不是:

mViewPager.getViewPager().setAdapter(new FragmentStatePagerAdapter(getSupportFragmentManager())

到:

mViewPager.getViewPager().setAdapter(new FragmentStatePagerAdapter(getChildFragmentManager())

因为当你到达这一行时:

mViewPager.getViewPager().setOffscreenPageLimit(mViewPager.getViewPager().getAdapter().getCount());

您没有访问正确的适配器。您正在获取 parent 的适配器，同时从 child 那里打电话。导致递归错误。

删除该行，您会收到适配器错误，因为您没有使用正确的 fragment 管理器开始。

讨论此问题的链接:

How to add a Fragment inside a ViewPager using Nested Fragment (Android 4.2)

Recursive entry to executePendingTransactions

ViewPager: Recursive entry to executePendingTransactions

如果您仍有问题，请告诉我。