安卓实现京东类别列表左右联动效果，仿饿了么点餐界面左右联动效果.zip

package com.cc.test; import android.graphics.Color; import android.os.Bundle; import android.support.design.widget.Snackbar; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.DividerItemDecoration; import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.util.Log; import android.view.View; import android.widget.TextView; import com.cc.test.adapter.LeftAdapter; import com.cc.test.adapter.RightAdapter; import com.cc.test.listener.RightItemCheckListener; import com.cc.test.model.RightBean; import com.cc.test.model.SortBean; import com.cc.test.view.ItemHeaderDecoration; import com.google.gson.Gson; import com.google.gson.reflect.TypeToken; import java.io.IOException; import java.io.InputStream; import java.util.ArrayList; import java.util.List; /** * 主界面 * 14点57分 * * @author cc */ public class MainActivity extends AppCompatActivity implements RightItemCheckListener { //左边的rv列表和适配器 private RecyclerView mRvLeft; private LeftAdapter leftAdapter; private LinearLayoutManager mLinearLayoutManager; //右边的rv列表和适配器 private RecyclerView mRvRight; private RightAdapter rightAdapter; private GridLayoutManager mManager; //总数据源 private List<SortBean> mSortBean = new ArrayList<>(); //右边的数据源 private List<RightBean> rightBeanList = new ArrayList<>(); //头部吸附自定义分割线 private ItemHeaderDecoration mDecoration; private boolean move = false; //标量 private int mIndex = 0; //点击左边某一个具体的item的位置 private int targetPosition; //是否可移动 private boolean isMoved; /** * 开始 * * @param savedInstanceState */ @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); //加载默认数据 getDefaultData(); //初始化控件 initLeftView(); initRightView(); } /** * 获取默认数据 */ private void getDefaultData() { //获取asset目录下的资源文件 String assetsData = getAssetsData("data.json"); Gson gson = new Gson(); //mSortBean就是要使用的集合啦 mSortBean = gson.fromJson(assetsData, new TypeToken<List<SortBean>>() { }.getType()); } /** * 初始化左边的rv及绑定适配器 */ private void initLeftView() { mRvLeft = (RecyclerView) findViewById(R.id.rv_left); mLinearLayoutManager = new LinearLayoutManager(this); mRvLeft.setLayoutManager(mLinearLayoutManager); DividerItemDecoration decoration = new DividerItemDecoration(this, DividerItemDecoration.VERTICAL); mRvLeft.addItemDecoration(decoration); //左边的item要填充的内容啦 List<String> leftTitle = new ArrayList<>(); //初始化左侧列表数据 for (int i = 0; i < mSortBean.size(); i++) { leftTitle.add(mSortBean.get(i).getName()); } //左边的adapter开始实现并处理item的点击事件 leftAdapter = new LeftAdapter(this, leftTitle, (id, position) -> { //可以移动啦 isMoved = true; //目标的下标 targetPosition = position; //去设置 setChecked(position, true); }); //绑定适配器 mRvLeft.setAdapter(leftAdapter); } /** * 创建右边的布局 */ private void initRightView() { //获取右边的控件 mRvRight = (RecyclerView) findViewById(R.id.rv_right); //监听右边的滑动事件 mRvRight.addOnScrollListener(new RecyclerViewListener()); //创建item布局管理器 mManager = new GridLayoutManager(this, 3); //通过isTitle的标志来判断是否是头部吸附title mManager.setSpanSizeLookup(new GridLayoutManager.SpanSizeLookup() { @Override public int getSpanSize(int position) { return rightBeanList.get(position).isTitle() ? 3 : 1; } }); //设置布局管理 mRvRight.setLayoutManager(mManager); //点击事件 rightAdapter = new RightAdapter(this, rightBeanList, (id, position) -> { String content = ""; switch (id) { case R.id.root: content = "title"; break; case R.id.content: content = "content"; break; } Snackbar snackbar = Snackbar.make(mRvRight, "当前点击的是" + content + ":" + rightBeanList.get(position).getName(), Snackbar.LENGTH_SHORT); View mView = snackbar.getView(); mView.setBackgroundColor(Color.BLUE); TextView text = mView.findViewById(android.support.design.R.id.snackbar_text); text.setTextColor(Color.WHITE); text.setTextSize(25); snackbar.show(); }); //绑定适配器 mRvRight.setAdapter(rightAdapter); //创建一个自定义分割线，给右边的列表布局添加上 mDecoration = new ItemHeaderDecoration(this, rightBeanList); mRvRight.addItemDecoration(mDecoration); //分割线点击事件 mDecoration.setCheckListener(this); //循环遍历数据源 for (int i = 0; i < mSortBean.size(); i++) { //将一级数据添加为头部数据（就左边的列表数据） RightBean head = new RightBean(mSortBean.get(i).getName()); //头部设置为true head.setTitle(true); head.setTitleName(mSortBean.get(i).getName()); //这里的tag不能为空，不能重复，是滑动对比用的 head.setTag(String.valueOf(i)); //添加到右边的数据源集合里面去 rightBeanList.add(head); //开始遍历二级数据，真正在右边item加载的数据 List<SortBean.CategoryTwoArrayBean> categoryTwoArray = mSortBean.get(i).getCategoryTwoArray(); //遍历 for (int j = 0; j < categoryTwoArray.size(); j++) { //遍历每一个并添加到右边的数据源里面 RightBean body = new RightBean(categoryTwoArray.get(j).getName()); body.setTag(String.valueOf(i)); String name = mSortBean.get(i).getName(); body.setTitleName(name); rightBeanList.add(body); } } //刷新 rightAdapter.notifyDataSetChanged(); mDecoration.setData(rightBeanList); } /** * 右边列表的滑动事件 */ private class RecyclerViewListener extends RecyclerView.OnScrollListener { @Override public void onScrollStateChanged(RecyclerView recyclerView, int newState) { super.onScrollStateChanged(recyclerView, newState); if (move && newState == RecyclerView.SCROLL_STATE_IDLE) { move = false; int n = mIndex - mManager.findFirstVisibleItemPosition(); if (0 <= n && n < mRvRight.getChildCount()) { int top = mRvRight.getChildAt(n).getTop(); mRvRight.smoothScrollBy(0, top); } } } @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) { super.onScrolled(recyclerView, dx, dy); if (move) { move = false; int n = mIndex - mManager.findFirstVisibleItemPosition(); if (0 <= n && n < mRvRight.getChildCount()) { int top = mRvRight.getChildAt(n).getTop()