【Android】高仿京东三级类型列表Demo

news/2024/7/8 4:42:08 标签: android

本demo基于二级分类双列表联动Demo进行了改进,高仿实现了京东的三级类型列表。
京东的如图:
在这里插入图片描述
本demo的:

改进之处

实现了三级列表联动,二三级列表之间的滑动监听优化了一下,将二级类型选中交予自身的点击事件,不再完全依靠三级列表的滑动回调。

上代码

引入的依赖

    //ShapeView
    implementation 'com.github.getActivity:ShapeView:9.0'
    //Gson解析
    implementation 'com.google.code.gson:gson:2.10.1'

ShapeView主要是美化一下二级条目,Gson是为了解析本地的类型json数据

条目布局

item_type_one

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/item_main_left_layout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:orientation="horizontal"
    android:padding="5dp">
    <TextView
        android:id="@+id/type"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="18sp"
        android:layout_marginVertical="15dp" />
</LinearLayout>

item_type_two

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="10dp"
    android:background="@color/flow">

    <com.hjq.shape.view.ShapeButton
        android:id="@+id/type"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginHorizontal="10dp"
        android:gravity="center"
        android:paddingHorizontal="10dp"
        android:paddingVertical="5dp"
        android:textSize="18sp"
        app:shape_radius="10dp"
        app:shape_solidColor="@android:color/transparent"
        app:shape_strokeColor="@color/common_accent_color"
        app:shape_strokeSize="1dp"
        app:shape_textColor="@color/common_accent_color"
        app:shape_textPressedColor="@android:color/white"
        app:shape_type="rectangle" />
</LinearLayout>

item_type_three

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:background="@drawable/radius_white"
    android:layout_margin="10dp"
    android:padding="10dp">

    <TextView
        android:id="@+id/type"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@color/black"
        android:paddingHorizontal="10dp"
        app:drawableEndCompat="@drawable/arrows_right_ic" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recycler"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>
</LinearLayout>

item_type_four(其实这个才是类型三,上面的是类型三的外围包裹,但是不想改了)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:gravity="center"
    android:orientation="vertical">

    <ImageView
        android:id="@+id/icon"
        android:src="@mipmap/ic_logo"
        android:layout_margin="5dp"
        android:layout_width="60dp"
        android:layout_height="60dp" />
    <TextView
        android:id="@+id/type"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="5dp"
        android:textSize="14sp"
        android:text="男鞋" />
</LinearLayout>

主页面布局

由两个列表变成了三个列表

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:background="@color/flow"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/one"
        android:layout_weight="7"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
    <LinearLayout
        android:layout_weight="3"
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/two"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>
        <androidx.recyclerview.widget.RecyclerView
            android:id="@+id/three"
            android:layout_weight="1"
            android:layout_marginTop="10dp"
            android:layout_width="match_parent"
            android:layout_height="0dp"/>
    </LinearLayout>
</LinearLayout>

适配器

OneTypeAdapter

public class OneTypeAdapter extends RecyclerView.Adapter<OneTypeAdapter.OneTypeHolder> {
    private final Context context;
    private final List<GoodsTypeBN> list;
    public int selectedPosition = 0;//当前选择的下标
    private OnItemClickListener onItemClickListener;

    public OneTypeAdapter(Context context, List<GoodsTypeBN> list) {
        this.context = context;
        this.list = list;
    }

    @NonNull
    @Override
    public OneTypeHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view= LayoutInflater.from(context).inflate(R.layout.item_type_one,parent,false);
        return new OneTypeHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull OneTypeHolder holder, @SuppressLint("RecyclerView") int position) {

        holder.type.setText(list.get(position).getType_name());
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (selectedPosition != holder.getAdapterPosition()) {
                    //点击了新的 item,更新状态
                    selectedPosition = holder.getAdapterPosition();
                }
                if (onItemClickListener!=null){
                    onItemClickListener.onItemClickListener(v,position);
                }
                notifyDataSetChanged();
            }
        });
        if (position==selectedPosition){
            holder.type.setTextColor(context.getColor(R.color.red));
            holder.type.setTextSize(30);
        }
        else {
            holder.type.setTextColor(context.getColor(R.color.black));
            holder.type.setTextSize(18);
        }
    }

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

    public static class OneTypeHolder extends RecyclerView.ViewHolder{
        TextView type;
        public OneTypeHolder(@NonNull View itemView) {
            super(itemView);
            type = itemView.findViewById(R.id.type);
        }
    }

    public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
        this.onItemClickListener = onItemClickListener;
    }

    public interface OnItemClickListener {
        void onItemClickListener(View v, int position);
    }
}

TwoTypeAdapter

public class TwoTypeAdapter extends RecyclerView.Adapter<TwoTypeAdapter.TwoTypeHolder> {
    private Context context;
    private List<GoodsTypeBN> list;
    private OnItemClickListener onItemClickListener;
    public int selectPosition=0;

    public TwoTypeAdapter(Context context, List<GoodsTypeBN> list) {
        this.context = context;
        this.list = list;
    }

    @NonNull
    @Override
    public TwoTypeHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view= LayoutInflater.from(context).inflate(R.layout.item_type_two,parent,false);
        return new TwoTypeHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull TwoTypeHolder holder, int position) {
        holder.type.setText(list.get(position).getType_name());
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                selectPosition=position;
                notifyDataSetChanged();
                if (onItemClickListener!=null){
                    onItemClickListener.onItemClickListener(view,position);
                }
            }
        });
        if (position==selectPosition){
            holder.type.setTextColor(context.getColor(R.color.common_accent_color));
            holder.type.getShapeDrawableBuilder()
                    .setStrokeColor(context.getColor(R.color.common_accent_color))
                    .intoBackground();
        }
        else {
            holder.type.setTextColor(context.getColor(R.color.grey));
            holder.type.getShapeDrawableBuilder()
                    .setStrokeColor(context.getColor(R.color.grey))
                    .intoBackground();
        }
    }

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

    public static class TwoTypeHolder extends RecyclerView.ViewHolder{
        ShapeButton type;
        public TwoTypeHolder(@NonNull View itemView) {
            super(itemView);
            type = itemView.findViewById(R.id.type);
        }
    }
    public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
        this.onItemClickListener = onItemClickListener;
    }

    public interface OnItemClickListener {
        void onItemClickListener(View v, int position);
    }
}

注意这里,这里二级条目的点击事件下,会将自身选中,自己来选中自己,然后更新,不再交由列表的滑动来更新。
在这里插入图片描述
在这里插入图片描述

之前的是这样。因为后面的几个条目点击存在一些问题。
在这里插入图片描述

在这里插入图片描述
ThreeTypeAdapter

public class ThreeTypeAdapter extends RecyclerView.Adapter<ThreeTypeAdapter.ThreeTYpeHolder> {
    private final Context context;
    private final List<GoodsTypeBN> list;
    public ThreeTypeAdapter(Context context, List<GoodsTypeBN> list) {
        this.context = context;
        this.list = list;
    }
    @NonNull
    @Override
    public ThreeTYpeHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view= LayoutInflater.from(context).inflate(R.layout.item_type_three,parent,false);
        return new ThreeTYpeHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ThreeTYpeHolder holder, int position) {
        holder.type.setText(list.get(position).getType_name());

        holder.recyclerView.setAdapter(new FourAdapter(context,list.get(position).getNextType()));
        holder.recyclerView.setLayoutManager(new GridLayoutManager(context,3));
    }

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

    public static class ThreeTYpeHolder extends RecyclerView.ViewHolder{
        TextView type;
        RecyclerView recyclerView;
        public ThreeTYpeHolder(@NonNull View itemView) {
            super(itemView);
            type = itemView.findViewById(R.id.type);
            recyclerView = itemView.findViewById(R.id.recycler);
        }
    }
}

FourAdapter

public class FourAdapter extends RecyclerView.Adapter<FourAdapter.FourHolder> {
    private final Context context;
    private final List<GoodsTypeBN> list;

    public FourAdapter( Context context,List<GoodsTypeBN> list) {
        this.context = context;
        this.list = list;
    }

    @NonNull
    @Override
    public FourHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view= LayoutInflater.from(context).inflate(R.layout.item_type_four,parent,false);
        return new FourHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull FourHolder holder, int position) {
        GoodsTypeBN goodsTypeBN=list.get(position);
        holder.type.setText(goodsTypeBN.getType_name());
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(context, "点击了"+goodsTypeBN.getType_name(), Toast.LENGTH_SHORT).show();
            }
        });
    }

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

    public static class FourHolder extends RecyclerView.ViewHolder{
        TextView type;
        ImageView icon;
        public FourHolder(@NonNull View itemView) {
            super(itemView);
            type = itemView.findViewById(R.id.type);
            icon = itemView.findViewById(R.id.icon);
        }
    }
}

主要代码

GoodsTypeBN类

public class GoodsTypeBN {
    private String type_id;
    private String type_name;
    private String parent_id;
    private String type_lv;
    private List<GoodsTypeBN> nextType;

    public String getType_id() {
        return type_id;
    }

    public void setType_id(String type_id) {
        this.type_id = type_id;
    }

    public String getType_name() {
        return type_name;
    }

    public void setType_name(String type_name) {
        this.type_name = type_name;
    }

    public String getParent_id() {
        return parent_id;
    }

    public void setParent_id(String parent_id) {
        this.parent_id = parent_id;
    }

    public String getType_lv() {
        return type_lv;
    }

    public void setType_lv(String type_lv) {
        this.type_lv = type_lv;
    }

    public List<GoodsTypeBN> getNextType() {
        return nextType;
    }

    public void setNextType(List<GoodsTypeBN> nextType) {
        this.nextType = nextType;
    }

    @Override
    public String toString() {
        return "GoodsTypeBN{" +
                "type_id='" + type_id + '\'' +
                ", type_name='" + type_name + '\'' +
                ", parent_id='" + parent_id + '\'' +
                ", type_lv='" + type_lv + '\'' +
                ", nextType=" + nextType +
                '}';
    }
}

主页面逻辑

				//一级类型条目点击
                oneTypeAdapter.setOnItemClickListener(new OneTypeAdapter.OnItemClickListener() {
                    @Override
                    public void onItemClickListener(View v, int position) {
                        //更换二级三级类型的数据
                        typeTwo.clear();
                        typeTwo.addAll(typeOne.get(position).getNextType());
                        twoTypeAdapter.selectPosition=0;
                        twoTypeAdapter.notifyDataSetChanged();
                        threeTypeAdapter.notifyDataSetChanged();
                    }
                });
                //二级类型条目点击
                twoTypeAdapter.setOnItemClickListener(new TwoTypeAdapter.OnItemClickListener() {
                    @Override
                    public void onItemClickListener(View v, int position) {
                        //将三级类型滑动到相应位置
                        LinearLayoutManager threeLayoutManager = ((LinearLayoutManager) three.getLayoutManager());
                        if (threeLayoutManager!=null){
                            threeLayoutManager.scrollToPositionWithOffset(position,0);
                        }
                    }
                });
                //添加三级类型滑动监听
                three.addOnScrollListener(onScrollListener);

添加滑动监听

RecyclerView.OnScrollListener onScrollListener = new RecyclerView.OnScrollListener() {

        /**
         获取第一个可见的item的position
         */
        int currentPosition = 0;
        @Override
        public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
            LinearLayoutManager twoLayoutManager = (LinearLayoutManager) two.getLayoutManager();
            LinearLayoutManager threeLayoutManager = ((LinearLayoutManager) three.getLayoutManager());
            if (twoLayoutManager!=null&&threeLayoutManager!=null){
                currentPosition = threeLayoutManager.findFirstCompletelyVisibleItemPosition();
                /**
                 这地方需要进行判断,如果下面的Recycle在移动的时候,上面的RecyclerView也是需要进行移动的
                 上面的recyclerview有可能会不可见,这时候,我们必须去判断一下,上面最后的一个item是不是
                 小于下面滑动的位置,或上面第一个item是不是大于下面滑动的位置
                 */
                if (twoLayoutManager.findFirstCompletelyVisibleItemPosition() > currentPosition) {
                    twoLayoutManager.scrollToPositionWithOffset(currentPosition, 0);
                } else if (twoLayoutManager.findFirstCompletelyVisibleItemPosition() < currentPosition) {
                    twoLayoutManager.scrollToPositionWithOffset(currentPosition, 0);
                }

                // 判断滚动的方向和位置,判断是否触发了回弹效果
                if (dy < 0 && !recyclerView.canScrollVertically(-1)) {
                    // 触发了上拉的回弹效果
                    Log.e("TAG", "onScrolled: 触发了上拉的回弹效果" );
                } else if (dy > 0 && !recyclerView.canScrollVertically(1)) {
                    // 触发了下拉的回弹效果
                    currentPosition = typeTwo.size() - 1;
                    Log.e("TAG", "onScrolled: 触发了下拉的回弹效果" );
                }
                twoTypeAdapter.selectPosition=currentPosition;
                twoTypeAdapter.notifyDataSetChanged();
            }
        }
    };

全部代码

public class MainActivity extends AppCompatActivity {
    private OneTypeAdapter oneTypeAdapter;
    private TwoTypeAdapter twoTypeAdapter;
    private ThreeTypeAdapter threeTypeAdapter;
    private List<GoodsTypeBN> typeOne;
    private List<GoodsTypeBN> typeTwo=new ArrayList<>();
    private List<GoodsTypeBN> typeThree=new ArrayList<>();
    private RecyclerView one,two,three;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        one=findViewById(R.id.one);
        two=findViewById(R.id.two);
        three=findViewById(R.id.three);
        init();
    }

    private void init(){
        String json = getJson(this, "category.json");
        if (!TextUtils.isEmpty(json)){
            //解析数据
            List<GoodsTypeBN> typeBNBaseEN=new Gson().fromJson(json, new TypeToken<List<GoodsTypeBN>>(){}.getType());
            if (typeBNBaseEN!=null){
                typeOne=typeBNBaseEN;
                //设置一级类型
                oneTypeAdapter=new OneTypeAdapter(this,typeOne);
                one.setLayoutManager(new LinearLayoutManager(this));
                one.setAdapter(oneTypeAdapter);

                //设置初始二级类型
                typeTwo.clear();
                typeTwo.addAll(typeOne.get(0).getNextType());
                twoTypeAdapter=new TwoTypeAdapter(this,typeTwo);
                LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
                linearLayoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);
                two.setLayoutManager(linearLayoutManager);
                two.setAdapter(twoTypeAdapter);

                //设置初始三级类型
                typeThree.clear();
                typeThree.addAll(typeTwo.get(0).getNextType());
                threeTypeAdapter=new ThreeTypeAdapter(this,typeTwo);
                three.setLayoutManager(new LinearLayoutManager(this));
                three.setAdapter(threeTypeAdapter);

                //一级类型条目点击
                oneTypeAdapter.setOnItemClickListener(new OneTypeAdapter.OnItemClickListener() {
                    @Override
                    public void onItemClickListener(View v, int position) {
                        //更换二级三级类型的数据
                        typeTwo.clear();
                        typeTwo.addAll(typeOne.get(position).getNextType());
                        twoTypeAdapter.selectPosition=0;
                        twoTypeAdapter.notifyDataSetChanged();
                        threeTypeAdapter.notifyDataSetChanged();
                    }
                });
                //二级类型条目点击
                twoTypeAdapter.setOnItemClickListener(new TwoTypeAdapter.OnItemClickListener() {
                    @Override
                    public void onItemClickListener(View v, int position) {
                        //将三级类型滑动到相应位置
                        LinearLayoutManager threeLayoutManager = ((LinearLayoutManager) three.getLayoutManager());
                        if (threeLayoutManager!=null){
                            threeLayoutManager.scrollToPositionWithOffset(position,0);
                        }
                    }
                });
                //添加三级类型滑动监听
                three.addOnScrollListener(onScrollListener);
            }
        }
    }
    RecyclerView.OnScrollListener onScrollListener = new RecyclerView.OnScrollListener() {

        /**
         获取第一个可见的item的position
         */
        int currentPosition = 0;
        @Override
        public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
            LinearLayoutManager twoLayoutManager = (LinearLayoutManager) two.getLayoutManager();
            LinearLayoutManager threeLayoutManager = ((LinearLayoutManager) three.getLayoutManager());
            if (twoLayoutManager!=null&&threeLayoutManager!=null){
                currentPosition = threeLayoutManager.findFirstCompletelyVisibleItemPosition();
                /**
                 这地方需要进行判断,如果下面的Recycle在移动的时候,上面的RecyclerView也是需要进行移动的
                 上面的recyclerview有可能会不可见,这时候,我们必须去判断一下,上面最后的一个item是不是
                 小于下面滑动的位置,或上面第一个item是不是大于下面滑动的位置
                 */
                if (twoLayoutManager.findFirstCompletelyVisibleItemPosition() > currentPosition) {
                    twoLayoutManager.scrollToPositionWithOffset(currentPosition, 0);
                } else if (twoLayoutManager.findFirstCompletelyVisibleItemPosition() < currentPosition) {
                    twoLayoutManager.scrollToPositionWithOffset(currentPosition, 0);
                }

                // 判断滚动的方向和位置,判断是否触发了回弹效果
                if (dy < 0 && !recyclerView.canScrollVertically(-1)) {
                    // 触发了上拉的回弹效果
                    Log.e("TAG", "onScrolled: 触发了上拉的回弹效果" );
                } else if (dy > 0 && !recyclerView.canScrollVertically(1)) {
                    // 触发了下拉的回弹效果
                    currentPosition = typeTwo.size() - 1;
                    Log.e("TAG", "onScrolled: 触发了下拉的回弹效果" );
                }
                twoTypeAdapter.selectPosition=currentPosition;
                twoTypeAdapter.notifyDataSetChanged();
            }
        }
    };


    public static String getJson(Context context, String fileName) {
        StringBuilder stringBuilder = new StringBuilder();
        //获得assets资源管理器
        AssetManager assetManager = context.getAssets();
        //使用IO流读取json文件内容
        try {
            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(
                    assetManager.open(fileName), StandardCharsets.UTF_8));
            String line;
            while ((line = bufferedReader.readLine()) != null) {
                stringBuilder.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return stringBuilder.toString();
    }
}

源码

github:https://github.com/panzhusheng/JDCategorydemo
gitee:https://gitee.com/pan-zs/JDCategorydemo


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