效果图.png

开篇

有一个需求，需要做一个左右双向联动的列表。类似于饿了么点餐页面，但是远没有那么复杂，只是用于展示的一个页面。只用了两个RecycleView加适配器，没有调用Fragment。

MainActivity

public class MainActivity extends Activity {

    private RecyclerView mRvClass;
    private RecyclerView mRvStudent;
    private ClassAdapter classAdapter;
    private StudentAdapter studentAdapter;

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

        initView();
        initAdapter();
    }


    private void initView() {
        mRvClass = findViewById(R.id.rv_class);
        mRvStudent = findViewById(R.id.rv_student);
    }

    private void initAdapter() {
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(MainActivity.this);
        mRvClass.setLayoutManager(linearLayoutManager);
        classAdapter = new ClassAdapter(MainActivity.this);
        mRvClass.setAdapter(classAdapter);
        //设置默认的选取状态
        mRvClass.setScrollingTouchSlop(0);

        LinearLayoutManager linearLayoutManager1 = new LinearLayoutManager(MainActivity.this);
        mRvStudent.setLayoutManager(linearLayoutManager1);
        studentAdapter = new StudentAdapter(MainActivity.this);
        mRvStudent.setAdapter(studentAdapter);

        /**
         * 左侧列表的事件处理
         * */
        classAdapter.setOnItemClickListener(new ClassAdapter.OnItemClickListener() {
            @Override
            public void onItemClick(View view, int position) {
                mRvClass.setScrollingTouchSlop(position);
                studentAdapter.setData(position);
                studentAdapter.notifyDataSetChanged();
            }
        });
    }
}

activity_main

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

    <android.support.v7.widget.RecyclerView
        android:id="@+id/rv_class"
        android:layout_width="90dp"
        android:layout_height="match_parent" />

    <View
        android:layout_width="1dp"
        android:layout_height="match_parent"
        android:background="#363636" />

    <android.support.v7.widget.RecyclerView
        android:id="@+id/rv_student"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginLeft="2dp" />
</LinearLayout>

ClassAdapter

public class ClassAdapter extends RecyclerView.Adapter<ClassAdapter.ViewHolder> {

    private Context context;
    private OnItemClickListener mOnItemClickListener = null;
    private List<Boolean> isClicks;//控件是否被点击,默认为false，如果被点击，改变值，控件根据值改变自身颜色

    public ClassAdapter(Context context) {

        this.context = context;
        isClicks = new ArrayList<>();
        for (int i = 0; i < 10; i++) {
            isClicks.add(false);
            if (i == 0) {
                isClicks.set(0, true);
            }
        }

    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(context).inflate(R.layout.class_layout, parent, false);
        ClassAdapter.ViewHolder holder = new ClassAdapter.ViewHolder(view);

        return holder;
    }

    @Override
    public void onBindViewHolder(@NonNull final ViewHolder holder, final int position) {

        holder.itemView.setTag(holder.tv_class_name);


        if (isClicks.get(position)) {
            holder.tv_class_name.setTextColor(Color.parseColor("#ff0000"));
        } else {
            holder.tv_class_name.setTextColor(Color.parseColor("#000000"));
        }

        holder.tv_class_name.setText("年级" + position);

        // 如果设置了回调，则设置点击事件
        if (mOnItemClickListener != null) {
            holder.itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    for (int i = 0; i < isClicks.size(); i++) {
                        isClicks.set(i, false);
                    }
                    isClicks.set(position, true);
                    notifyDataSetChanged();
                    mOnItemClickListener.onItemClick(holder.itemView, position);
                }
            });
        }
    }

    @Override
    public int getItemCount() {
        return 10;
    }

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

    public interface OnItemClickListener {

        void onItemClick(View view, int position);

    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        private TextView tv_class_name;

        public ViewHolder(@NonNull View itemView) {
            super(itemView);
            tv_class_name = itemView.findViewById(R.id.tv_class_name);
        }
    }
}

StudentAdapter

public class StudentAdapter extends RecyclerView.Adapter<StudentAdapter.ViewHolder> {

    private Context context;
    private int i = 0;

    public StudentAdapter(Context context) {
        this.context = context;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {

        View view = LayoutInflater.from(context).inflate(R.layout.student_layout, parent, false);
        StudentAdapter.ViewHolder holder = new StudentAdapter.ViewHolder(view);

        return holder;
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        holder.tv_name.setText("学生+" + i);
    }

    @Override
    public int getItemCount() {
        return 10;
    }

    public void setData(int position) {
        this.i = position;
    }


    public class ViewHolder extends RecyclerView.ViewHolder {
        private TextView tv_name;

        public ViewHolder(@NonNull View itemView) {
            super(itemView);
            tv_name = itemView.findViewById(R.id.tv_name);
        }
    }
}

（另加 RecycleView中Item的，点击改变颜色，点击其他项改变颜色，上一次点击的变回原来的颜色）