Android RecyclerView：将布局文件LIST更改为GRID onOptionItemSelected

Question

我正在开发一个在线购物的Android应用程序。我使用RecyclerView为产品列表创建了以下视图，因为我想在选择选项菜单项时更改视图：

我创建了以下名为ProductAdapter的 adapter ，因为我已经实现了在onCreateViewHolder中更改布局的代码，用于根据布尔值选择布局文件。

适配器代码ProductAdapter ：

    /***
     * ADAPTER for Product to binding rows in List
     */
    private class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ProductRowHolder> {

        private List<Product> productList;

        private Context mContext;

        public ProductAdapter(Context context, List<Product> feedItemList) {
            this.productList = feedItemList;
            this.mContext = context;
        }

        @Override
        public ProductRowHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
            View v = LayoutInflater.from(viewGroup.getContext()).inflate(isProductViewAsList ? R.layout.product_row_layout_list : R.layout.product_row_layout_grid, null);
            ProductRowHolder mh = new ProductRowHolder(v);
            return mh;
        }

        @Override
        public void onBindViewHolder(ProductRowHolder  productRowHolder, int i) {
            Product prodItem = productList.get(i);

//            Picasso.with(mContext).load(feedItem.getName())
//                    .error(R.drawable.ic_launcher)
//                    .placeholder(R.drawable.ic_launcher)
//                    .into(productRowHolder.thumbnail);


            double price = prodItem.getPrice();
            double discount = prodItem.getDiscount();
            double discountedPrice = price - (price * discount / 100);

            String code = "";
            if(prodItem.getCode() != null)
                code = "[" + prodItem.getCode() + "] ";

            productRowHolder.prodIsNewView.setVisibility(prodItem.getIsNew() == 1 ? View.VISIBLE : View.INVISIBLE);
            productRowHolder.prodNameView.setText(code + prodItem.getName());
            productRowHolder.prodOriginalRateView.setText("Rs." + new BigDecimal(price).setScale(2,RoundingMode.DOWN));
            productRowHolder.prodDiscView.setText("" + new BigDecimal(discount).setScale(2,RoundingMode.DOWN) + "% off");
            productRowHolder.prodDiscRateView.setText("Rs." + new BigDecimal(discountedPrice).setScale(2,RoundingMode.DOWN));

            productRowHolder.prodOriginalRateView.setPaintFlags(productRowHolder.prodOriginalRateView.getPaintFlags() | Paint.STRIKE_THRU_TEXT_FLAG);
        }

        @Override
        public int getItemCount() {
            return (null != productList ? productList.size() : 0);
        }

        public class ProductRowHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
            //Declaration of Views

            public ProductRowHolder(View view) {
                super(view);

                view.setOnClickListener(this);

                //Find Views
            }

            @Override
            public void onClick(View view) {
               //Onclick of row
            }
        }
    }

之后我完成了将RecyclerView布局从List更改为Grid以及onOptionsItemSelected中的反Versa的代码，在这里我打电话给mAdapter.notifyDataSetChanged();所以它将再次调用适配器并更改值。

onOptionsItemSelected ：

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        switch (id) {
            case R.id.action_settings:
                return true;
            case android.R.id.home:
                finish();
                break;
            case R.id.product_show_as_view:
                isProductViewAsList = !isProductViewAsList;
                supportInvalidateOptionsMenu();
                mRecyclerView.setLayoutManager(isProductViewAsList ? new LinearLayoutManager(this) : new GridLayoutManager(this, 2));
                mAdapter.notifyDataSetChanged();
                break;
        }

        return super.onOptionsItemSelected(item);
    }

我得到了一些成功，如：

Grid布局的图片：

List布局的图片：

现在，当我滚动然后更改视图正在显示时：

Grid布局：

List布局：

我不知道滚动后为什么会这样。有没有其他方法来改变这样的观点。

  

今天我刚看到这个问题是因为ImageView而没有它完美运作。

请帮助，我们将不胜感激。

Answer 1

我找到了解决方案，其中包含我设置的活动 LinearLayoutManager ，如：

mLayoutManager = new LinearLayoutManager(this);
mProductListRecyclerView.setLayoutManager(mLayoutManager);

之后 onOptionsItemSelected 写成：

case R.id.menu_product_change_view:
     isViewWithCatalog = !isViewWithCatalog;
     supportInvalidateOptionsMenu();
     //loading = false;
     mProductListRecyclerView.setLayoutManager(isViewWithCatalog ? new LinearLayoutManager(this) : new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL));
     mProductListRecyclerView.setAdapter(mAdapter);
     break;

并在 onCreateViewHolder 中更改视图，例如：

@Override
public ProductRowHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
    View v = LayoutInflater.from(viewGroup.getContext()).inflate(isViewWithCatalog ? R.layout.product_row_layout_list : R.layout.product_row_layout_grid, null);
    ProductRowHolder mh = new ProductRowHolder(v);
    return mh;
}

从开始到结束，您必须管理 isViewWithCatalog 变量，以便首先显示哪个布局。

Answer 2

我通过在更改布局管理器后再次将适配器设置为RecyclerView来解决了这个问题。

listView.setLayoutManager(new LinearLayoutManager(this));
listView.setAdapter(adapter);

Answer 3

在这个SDK samples中有一个完整的例子，但它为LayoutManagers使用了一个布局文件

为了在切换布局时保持滚动位置，他们使用了这个功能

public void setRecyclerViewLayoutManager(LayoutManagerType layoutManagerType) {
    int scrollPosition = 0;

    // If a layout manager has already been set, get current scroll position.
    if (mRecyclerView.getLayoutManager() != null) {
        scrollPosition = ((LinearLayoutManager) mRecyclerView.getLayoutManager())
                .findFirstCompletelyVisibleItemPosition();
    }

    switch (layoutManagerType) {
        case GRID_LAYOUT_MANAGER:
            mLayoutManager = new GridLayoutManager(getActivity(), SPAN_COUNT);
            mCurrentLayoutManagerType = LayoutManagerType.GRID_LAYOUT_MANAGER;
            break;
        case LINEAR_LAYOUT_MANAGER:
            mLayoutManager = new LinearLayoutManager(getActivity());
            mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
            break;
        default:
            mLayoutManager = new LinearLayoutManager(getActivity());
            mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
    }

    mRecyclerView.setLayoutManager(mLayoutManager);
    mRecyclerView.scrollToPosition(scrollPosition);
}

Answer 4

我认为在滚动并更改回网格视图后，不会重新创建第一个项目。我通过覆盖getItemViewType()解决了这个问题，并相应地对onCreateViewHolder中的布局文件进行了充气。

Answer 5

我使用viewflipper并使用动画更改类型显示列表。和美丽。

主xml中的

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

<ViewFlipper android:id="@+id/view_flipper"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <android.support.v7.widget.RecyclerView 
        android:id="@+id/small_list"   android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="match_parent" android:overScrollMode="never" />
    <android.support.v7.widget.RecyclerView android:scrollbarStyle="insideInset"
        android:id="@+id/big_list"  android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="match_parent" android:overScrollMode="never" />
    <android.support.v7.widget.RecyclerView android:scrollbarStyle="insideInset"
        android:id="@+id/grid_list" android:paddingLeft="2.0dip" android:paddingRight="2.0dip" android:layout_width="match_parent" android:layout_height="match_parent" android:overScrollMode="never" />
</ViewFlipper>

活动中的所有代码

    private RecyclerView smallRecycleView;
private RecyclerView gridRecycleView;
private RecyclerView bigRecycleView;

private StaggeredGridLayoutManager gridLayoutManager;
private LinearLayoutManager bigLayoutManager;
private LinearLayoutManager smallLayoutManager;

private AAdapter adapterGrid;
private AAdapter adapterSmall;
private AAdapter adapterBig;

private ViewFlipper viewFlipper;


private TypeShow typeShowList = TypeShow.Small;


private AList list = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
    setLayout( R.layout.main_layout);
    super.onCreate(savedInstanceState);

    try {

        list = getItems(10);


        viewFlipper = ((ViewFlipper)findViewById(R.id.view_flipper));
        viewFlipper.setOutAnimation(MainActivity.this, R.anim.anim_fade_out_flip);
        viewFlipper.setInAnimation(MainActivity.this, R.anim.anim_fade_in_flip);

        smallRecycleView = ((RecyclerView)findViewById(R.id.small_list));
        gridRecycleView = ((RecyclerView)findViewById(R.id.grid_list));
        bigRecycleView = ((RecyclerView)findViewById(R.id.big_list));

        smallRecycleView.setHasFixedSize(false);
        gridRecycleView.setHasFixedSize(false);
        bigRecycleView.setHasFixedSize(false);

        smallLayoutManager = new LinearLayoutManager(MainActivity.this);
        smallRecycleView.setLayoutManager(smallLayoutManager);
        gridLayoutManager = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL);
        gridRecycleView.setLayoutManager(gridLayoutManager);
        gridRecycleView.setItemAnimator(null);
        bigLayoutManager = new LinearLayoutManager(MainActivity.this);
        bigRecycleView.setLayoutManager(bigLayoutManager);


        adapterSmall = new AAdapter(MainActivity.this,list,MainActivity.this,TypeShow.Small);
        smallRecycleView.setAdapter(adapterSmall);

        adapterGrid = new AAdapter(MainActivity.this,list,MainActivity.this,TypeShow.Grid);
        gridRecycleView.setAdapter(adapterGrid);

        adapterBig = new AAdapter(MainActivity.this,list,MainActivity.this,TypeShow.Big);
        bigRecycleView.setAdapter(adapterBig);





        if (Build.VERSION.SDK_INT >= 11)
        {
            smallRecycleView.setVerticalScrollbarPosition(1);
            gridRecycleView.setVerticalScrollbarPosition(1);
            bigRecycleView.setVerticalScrollbarPosition(1);
        }

        final FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.floating_action_button);
               fab.setOnClickListener(new View.OnClickListener() {
                       @Override
                       public void onClick(View view) {
                           smallRecycleView.setSelected(false);
                           bigRecycleView.setSelected(false);
                           gridRecycleView.setSelected(false);
                           viewFlipper.showNext();

                           if(typeShowList == TypeShow.Small){
                               typeShowList = TypeShow.Big;
                               fab.setImageResource(R.drawable.ic_type_grid);
                           }
                           else if(typeShowList == TypeShow.Big){
                               typeShowList = TypeShow.Grid;
                               fab.setImageResource(R.drawable.ic_atype_small);
                           }
                           else {
                               typeShowList = TypeShow.Small;
                               fab.setImageResource(R.drawable.ic_type_big);
                           }
                        }
               });
        fab.setImageResource(R.drawable.ic_type_big);

    }
    catch (Exception e){
    }
}

输入

public enum TypeShow {
Grid,
Small,
Big }

适配器

public class AAdapter extends RecyclerView.Adapter<AAdapter.PersonViewHolder> {

private AList noteList = null;
private MainActivity mContext;
private TypeShow typeShow; 

public AAdapter(MainActivity mContext, AList noteList, OnItemClickListener mListener, TypeShow typeShow){
    this.noteList = noteList;
    this.mContext= mContext;
    this.mListener= mListener;
    this.typeShow= typeShow; 
}

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

@Override
public PersonViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
    if(typeShow == TypeShow.Grid) {
        View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.activity_row_grid, viewGroup, false);
        return new PersonViewHolder(v);
    }
    else if(typeShow == TypeShow.Small) {

        View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.activity_row_small, viewGroup, false);
        return new PersonViewHolder(v);
    }
    else {  
        View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.activity_row_big, viewGroup, false);
        return new PersonViewHolder(v);
    }
}


@Override
public void onBindViewHolder(PersonViewHolder personViewHolder, int i) {
 }


public static class PersonViewHolder extends RecyclerView.ViewHolder {

    PersonViewHolder(View itemView) {
        super(itemView);

    }
}
}