滚动不适用于 BottomSheet 中的多个 RecyclerView

Question

我使用DialogFragment 方法实现了BottomSheet。我在BottomSheet 中有一个TabLayout 和ViewPager。 ViewPager 托管 2 个页面，每个页面扩展一个 RecyclerView。第一个（咖啡标签）RecyclerView 滚动良好。我现在遇到的问题是，对于第二个（牛奶标签），滚动不起作用。知道如何解决这个问题吗？谢谢！

您可以使用我在这里创建的演示项目进行测试：https://github.com/choongyouqi/bottomsheet`

Answer 1

正如 R. Zagórski 所说，我描述了这种滚动行为的原因here，即BottomSheetBehavior 仅支持一个滚动子项。然而，这个答案并不关注底部工作表对话框。

因此——就像 R. Zagórski 一样——我扩展了我自己的 library 以克服这个限制。 从 0.0.3 开始，支持底部工作表对话框！您可以在此处找到库和示例应用程序： https://github.com/laenger/ViewPagerBottomSheet

要在您的项目中使用，只需将 maven repo url 添加到您的 build.gradle：

repositories {
    maven { url "https://raw.github.com/laenger/maven-releases/master/releases" }
}

将库添加到依赖项：

dependencies {
    compile "biz.laenger.android:vpbs:0.0.3"
}

使用ViewPagerBottomSheetDialogFragment 作为对话框片段的超类。然后在内容视图中设置任何 ViewPager：

public class DialogFragment extends ViewPagerBottomSheetDialogFragment {
    @Override
    public void setupDialog(Dialog dialog, int style) {
        super.setupDialog(dialog, style);
        final View contentView = View.inflate(getContext(), R.layout.dialog_bottom_sheet, null);

        final ViewPager viewPager = (ViewPager) contentView.findViewById(R.id.viewpager);
        // ...
        BottomSheetUtils.setupViewPager(viewPager);

        dialog.setContentView(contentView);
    }
}

Answer 2

将此视图用作根视图：

import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.LinearLayout;

public class DisallowInterceptView extends LinearLayout {
    public DisallowInterceptView(Context context) {
        super(context);
        requestDisallowInterceptTouchEvent(true);
    }

    public DisallowInterceptView(Context context, AttributeSet attrs) {
        super(context, attrs);
        requestDisallowInterceptTouchEvent(true);
    }

    public DisallowInterceptView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        requestDisallowInterceptTouchEvent(true);
    }


    public boolean dispatchTouchEvent(MotionEvent ev) {
        getParent().requestDisallowInterceptTouchEvent(true);
        return super.dispatchTouchEvent(ev);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_MOVE:
                requestDisallowInterceptTouchEvent(true);
                break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL:
                requestDisallowInterceptTouchEvent(false);
                break;
        }
        return super.onTouchEvent(event);
    }

}

然后在用于bottmSheet的布局中：

<?xml version="1.0" encoding="utf-8"?>
<com.your.package.DisallowInterceptView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:maxHeight="400dp"
    android:minHeight="300dp"
    android:orientation="vertical"
    >

    ...
</LinearLayout>

</com.your.package.DisallowInterceptView>

Answer 3

当试图在 StackOverflow 上查找问题时，我发现了 this thread。它描述了这个错误（至少我是这么看的），BottomSheetBehaviour 仅适用于它找到的第一个可滚动子项。它还建议使用不同的CoordinatorLayout.Behavior 建议和发布here。

但是，您的情况有点不同。使用BottomSheetDialogFragment。这就是提供的解决方案不起作用的地方。但是，我设法克服了这个问题。已发布 repository，您的项目已修改为可以正常工作。它使用前面提到的库中的ViewPagerBottomSheetBehavior。

基本上进行了以下更改：

1. StatisticFragment 扩展 ViewPagerBottomSheetDialogFragment 而不是 BottomSheetDialogFragment

2. StatisticsFragment中的onCreateDialog函数发生了变化：

   @NonNull
   @Override
   public Dialog onCreateDialog(Bundle savedInstanceState) {
       ViewPagerBottomSheetDialog dialog = (ViewPagerBottomSheetDialog) super.onCreateDialog(savedInstanceState);
       View rootView = View.inflate(getContext(), R.layout.sheet_main, null);
       viewPager = (ViewPager) rootView.findViewById(R.id.viewpager);
       tabLayout = (TabLayout) rootView.findViewById(R.id.tabs);
       dialog.setContentView(rootView);
       mBehavior = ViewPagerBottomSheetBehavior.from((View) rootView.getParent());
       mBehavior.setPeekHeight(400);
       if (viewPager != null && tabLayout != null) {
           initViewPager();
       }
       return dialog;
   }
   

3. 在ViewPager 上调用以下函数：

   BottomSheetUtils.setupViewPager(viewPager);
   

仅此而已。该项目有效。

以下是在幕后完成的：

BottomSheetDialogFragment只有一种方法：

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    return new BottomSheetDialog(getContext(), getTheme());
}

返回BottomSheetDialog。但是，它的静态定义行为设置为BottomSheetBehavior。需要的是覆盖ViewPagerBottomSheetDialogFragment 以返回ViewPagerBottomSheetDialog，其中CoordinatorLayout.Behavior 设置为ViewPagerBottomSheetBehavior。此外，需要覆盖自定义的BottomSheet 以适应ViewPagerBottomSheetBehavior。

Answer 4

我遇到了同样的问题，要解决此问题而无需覆盖 BottomSheetBehavior 或需要额外的库，您可以执行以下操作： 在底部工作表实现中实现一个回调，以注册页面的更改。

fun onPageChanged(currentPage: Int) {
   recycler1.isNestedScrollingEnabled = currentPage == 0
   recycler2.isNestedScrollingEnabled = currentPage == 1
   dialog?.findViewById<FrameLayout>(R.id.design_bottom_sheet)?.requestLayout()
}

在 onLayoutChild 的 BottomSheetBehavior 实现中，会查找第一个支持嵌套滚动的子项，并通过此更改重复查找。不是最佳解决方案，但在我的情况下工作正常

Answer 5

你可以在 CoordinatorLayout 中使用 2 个 RecyclerView。

<android.support.design.widget.CoordinatorLayout
         android:id="@+id/mainBottomSheet"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:background="@color/white">

         <android.support.v7.widget.RecyclerView
                  android:id="@+id/recyclerViewRight"
                  android:layout_width="match_parent"
                  android:layout_height="match_parent" />

         <android.support.v7.widget.RecyclerView
                  android:id="@+id/recyclerViewLeft"
                  android:layout_width="200dp"
                  android:layout_height="match_parent" />

</android.support.design.widget.CoordinatorLayout>

查看此帖子link

Answer 6

更好的解决方案是在proguard规则中添加以下行：

-keep class androidx.viewpager.widget.ViewPager$LayoutParams { int position; }
-keep class com.google.android.material.bottomsheet.BottomSheetBehavior { *** findScrollingChild(...); }

更多详情请见此链接：https://github.com/kafumi/android-bottomsheet-viewpager#proguardr8

Answer 7

您无需将StatisticFragment 扩展为ViewPagerBottomSheetDialogFragment，也无需为此使用任何库。

是你的代码，我刚刚在你的Static Fragment 中做了一些与View Pager. 相关的更改

这是Statistic Fragment，我在其中进行了更改。

没有上述所有答案中所述的任何错误。

用您的旧 Static fragment 替换此代码，而不是任何其他更改，它将为您提供所需的输出。

我刚刚对您的View Pager 进行了更改，并使其按您的意愿工作。 使用OnPageChangeListener 方法即可获得该视图。

Statistic Fragment.java

    public class StatisticFragment extends BottomSheetDialogFragment {

        private BottomSheetBehavior mBehavior;
        private TabLayout tabLayout;
        private ViewPager viewPager;

        @NonNull
        @Override
        public Dialog onCreateDialog(Bundle savedInstanceState) {
            BottomSheetDialog dialog = (BottomSheetDialog) super.onCreateDialog(savedInstanceState);
            View rootView = View.inflate(getContext(), R.layout.sheet_main, null);

            viewPager = (ViewPager) rootView.findViewById(R.id.viewpager);
            tabLayout = (TabLayout) rootView.findViewById(R.id.tabs);
            if (viewPager != null && tabLayout != null) {
                initViewPager();
            }

            final ViewPager.OnPageChangeListener pageChangeListener = new ViewPager.OnPageChangeListener() {

                @Override
                public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

                }

                @Override
                public void onPageSelected(int arg0) {
                    // TODO Auto-generated method stub
                    View view = viewPager.findViewWithTag(arg0);
                    if (view == null) {
                        return;
                    }
                    CustomPagerAdapter adapter = new CustomPagerAdapter(getContext());
                    viewPager.setAdapter(adapter);
                    viewPager.setOffscreenPageLimit(10);
                    tabLayout.setupWithViewPager(viewPager);
                }

                @Override
                public void onPageScrollStateChanged(int state) {

                }
            };

            viewPager.addOnPageChangeListener(pageChangeListener);
            viewPager.post(new Runnable() {
                @Override
                public void run() {
                    pageChangeListener.onPageSelected(viewPager.getCurrentItem());
                }
            });


            dialog.setContentView(rootView);
            mBehavior = BottomSheetBehavior.from((View) rootView.getParent());
            return dialog;


        }

        private void initViewPager() {
            CustomPagerAdapter adapter = new CustomPagerAdapter(getContext());
            viewPager.setAdapter(adapter);
            viewPager.setOffscreenPageLimit(10);
            tabLayout.setupWithViewPager(viewPager);

        }

        @Override
        public void onStart() {
            super.onStart();
            //mBehavior.setState(BottomSheetBehavior.STATE_EXPANDED);
            //mBehavior.setState(BottomSheetBehavior.STATE_COLLAPSED);
        }

        public class ServiceVideHolder extends RecyclerView.ViewHolder {
            protected ViewGroup mItemView;
            protected TextView mNameView;
            protected TextView mCodeView;

            public ServiceVideHolder(View v) {
                super(v);
                //rootView = v;
                mItemView = (ViewGroup) v.findViewById(R.id.item);
                mNameView = (TextView) v.findViewById(R.id.main_text);
                mCodeView = (TextView) v.findViewById(R.id.sub_text);
            }
        }

        public class ItemViewHolder extends RecyclerView.ViewHolder {
            protected TextView mMainText;
            protected TextView mSubText;

            public ItemViewHolder(View v) {
                super(v);
                mMainText = (TextView) v.findViewById(R.id.main_text);
                mSubText = (TextView) v.findViewById(R.id.sub_text);
            }
        }

        public class ItemAdapter extends RecyclerView.Adapter<ItemViewHolder> {
            private List<Item> items;

            public ItemAdapter(List<Item> items) {
                this.items = items;
            }

            @Override
            public ItemViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
                View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.item, viewGroup, false);
                return new ItemViewHolder(view);
            }

            @Override
            public void onBindViewHolder(final ItemViewHolder viewHolder, final int position) {
                final Item item = items.get(position);
                viewHolder.mMainText.setText(item.name);
                viewHolder.mSubText.setText(item.value);
                viewHolder.mMainText.setTextColor(ResourcesCompat.getColor(getResources(), position % 2 == 0 ? R.color.md_red_500 : R.color.md_blue_500, null));
            }

            @Override
            public int getItemCount() {
                return items.size();
            }
        }

        class ViewPagerAdapter extends FragmentPagerAdapter {
            private final List<Fragment> mFragmentList = new ArrayList<>();
            private final List<String> mFragmentTitleList = new ArrayList<>();

            public ViewPagerAdapter(FragmentManager manager) {
                super(manager);
            }

            @Override
            public Fragment getItem(int position) {
                return mFragmentList.get(position);
            }

            @Override
            public int getCount() {
                return mFragmentList.size();
            }

            public void addFrag(Fragment fragment, String title) {
                mFragmentList.add(fragment);
                mFragmentTitleList.add(title);
            }

            @Override
            public CharSequence getPageTitle(int position) {
                return mFragmentTitleList.get(position);
            }
        }

        public class CustomPagerAdapter extends PagerAdapter {

            private Context mContext;

            public CustomPagerAdapter(Context context) {
                mContext = context;
            }

            @Override
            public Object instantiateItem(ViewGroup collection, int position) {
                //CustomPagerEnum customPagerEnum = CustomPagerEnum.values()[position];
                LayoutInflater inflater = LayoutInflater.from(mContext);
                ViewGroup rootView = (ViewGroup) inflater.inflate(R.layout.adapter, collection, false);
                rootView.setTag(position);


                Toast.makeText(mContext, "Inside Instanciate Item", Toast.LENGTH_SHORT).show();

                //View rootView = View.inflate(getContext(), R.layout.adapter, null);
                final RecyclerView mRecyclerView = (RecyclerView) rootView.findViewById(R.id.recycler_view);
                ArrayList<Item> items = new ArrayList<>();

                if (position == 0) {
                    items.add(new Item("Coffee 1", "1"));
                    items.add(new Item("Coffee 2", "2"));
                    items.add(new Item("Coffee 3", "3"));
                    items.add(new Item("Coffee 4", "4"));
                    items.add(new Item("Coffee 5", "5"));
                    items.add(new Item("Coffee 6", "6"));
                    items.add(new Item("Coffee 7", "7"));
                    items.add(new Item("Coffee 8", "8"));
                    items.add(new Item("Coffee 9", "9"));
                    items.add(new Item("Coffee 10", "10"));
                } else {
                    items.add(new Item("Milk 1", "1"));
                    items.add(new Item("Milk 2", "2"));
                    items.add(new Item("Milk 3", "3"));
                    items.add(new Item("Milk 4", "4"));
                    items.add(new Item("Milk 5", "5"));
                    items.add(new Item("Milk 6", "6"));
                    items.add(new Item("Milk 7", "7"));
                    items.add(new Item("Milk 8", "8"));
                    items.add(new Item("Milk 9", "9"));
                    items.add(new Item("Milk 10", "10"));
                }

                final ItemAdapter mAdapter = new ItemAdapter(items);

                mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false));
                mRecyclerView.setNestedScrollingEnabled(false);
                mRecyclerView.setAdapter(mAdapter);
                Paint paint = new Paint();
                paint.setStrokeWidth(1);
                paint.setColor(ResourcesCompat.getColor(getResources(), R.color.md_grey_500, null));
                paint.setAntiAlias(true);
                paint.setPathEffect(new DashPathEffect(new float[]{25.0f, 25.0f}, 0));
                mRecyclerView.addItemDecoration(new HorizontalDividerItemDecoration.Builder(getActivity()).showLastDivider().paint(paint).build()); //.marginResId(R.dimen.leftmargin, R.dimen.rightmargin)

                collection.addView(rootView);


                return rootView;
            }

            @Override
            public void destroyItem(ViewGroup collection, int position, Object view)    {
                collection.removeView((View) view);
            }

            @Override
            public int getCount() {
                return 2;
            }

            @Override
            public boolean isViewFromObject(View view, Object object) {
                return view == object;
            }

            @Override
            public CharSequence getPageTitle(int position) {
                //CustomPagerEnum customPagerEnum = CustomPagerEnum.values()[position];
                return position == 0 ? "Coffee" : "Milk";
            }

        }
    }

完成了。