Android(安卓)RecyclerView和ListView多布局实现
16lz
2021-01-26
前言
每个人每天都会在浏览器上看一些最新的新闻，作为一个IT程序员你们会发现，她们的布局排版都是有区别的，有时候同一个样式的条目有4、5条 界面一样，下面又出现1 条不一样的条目，这样的效果是不是很美观，这在Android称为多布局，下面来简单实现一下，大概理解下
使用
1.RecyclerView
利用Adapter的getItemViewType()方法返回不同的VIEW_TYPE，利用求末取余的算法获取到当前位置的条目，然后在onCreateViewHolder中设置对应的ViewHolder 。
final int VIEW_TYPE = 3; final int TYPE_1 = 0; final int TYPE_2 = 1; final int TYPE_3 = 2; /** * 获取每个位置的View * * @param position * @return */ @Override public int getItemViewType(int position) { int p = position % VIEW_TYPE; if (p == 0) { return TYPE_1; } else if (p == 1) { return TYPE_2; } else { return TYPE_3; } } @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { if (viewType == TYPE_1) { View view = View.inflate(mContext, R.layout.adapter, null); return new MyViewHolder(view); } else if (viewType == TYPE_2) { View view2 = View.inflate(mContext, R.layout.adapter2, null); return new MyViewHolder2(view2); } else { View view3 = View.inflate(mContext, R.layout.adapter3, null); return new MyViewHolder3(view3); } }这个方法是给每一个ViewHolder设置数据
@Override public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { MyViewHolder holder1 = null; MyViewHolder2 holder2 = null; MyViewHolder3 holder3 = null; if (holder instanceof MyViewHolder) { holder1 = (MyViewHolder) holder; } else if (holder instanceof MyViewHolder2) { holder2 = (MyViewHolder2) holder; } else { holder3 = (MyViewHolder3) holder; } }完整代码：
public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> { Context mContext; List mList; final int VIEW_TYPE = 3; final int TYPE_1 = 0; final int TYPE_2 = 1; final int TYPE_3 = 2; public MyAdapter(Context context, List list) { mContext = context; mList = list; } @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { if (viewType == TYPE_1) { View view = View.inflate(mContext, R.layout.adapter, null); return new MyViewHolder(view); } else if (viewType == TYPE_2) { View view2 = View.inflate(mContext, R.layout.adapter2, null); return new MyViewHolder2(view2); } else { View view3 = View.inflate(mContext, R.layout.adapter3, null); return new MyViewHolder3(view3); } } @Override public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { MyViewHolder holder1 = null; MyViewHolder2 holder2 = null; MyViewHolder3 holder3 = null; if (holder instanceof MyViewHolder) { holder1 = (MyViewHolder) holder; } else if (holder instanceof MyViewHolder2) { holder2 = (MyViewHolder2) holder; } else { holder3 = (MyViewHolder3) holder; } } /** * 获取每个位置的View * * @param position * @return */ @Override public int getItemViewType(int position) { int p = position % VIEW_TYPE; if (p == 0) { return TYPE_1; } else if (p == 1) { return TYPE_2; } else { return TYPE_3; } } @Override public int getItemCount() { if (mList != null) { return mList.size(); } return 0; } class MyViewHolder extends RecyclerView.ViewHolder { public MyViewHolder(View itemView) { super(itemView); } } class MyViewHolder2 extends RecyclerView.ViewHolder { public MyViewHolder2(View itemView) { super(itemView); } } class MyViewHolder3 extends RecyclerView.ViewHolder { public MyViewHolder3(View itemView) { super(itemView); } }} 2.ListView
ListView比RecyclerView多了getViewTypeCount() 布局数量 的方法
// 总共有几种布局 @Override public int getViewTypeCount() { return VIEW_TYPE; }完整代码：
public class MyAdapter2 extends BaseAdapter { private List list; private Context ctx; final int VIEW_TYPE = 3; final int TYPE_1 = 0; final int TYPE_2 = 1; final int TYPE_3 = 2; public MyAdapter2(List list, Context ctx) { super(); this.list = list; this.ctx = ctx; } // 获取Item的View的类型 @Override public int getItemViewType(int position) { int i = position % VIEW_TYPE; if (i == 0) { return TYPE_1; } else if (i == 1) { return TYPE_2; } else { return TYPE_3; } } // 总共有几种布局 @Override public int getViewTypeCount() { return VIEW_TYPE; } @Override public int getCount() { return list.size(); } @Override public Object getItem(int position) { return list.get(position); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { MyViewHolder holder1 = null; MyViewHolder2 holder2 = null; MyViewHolder3 holder3 = null; int type = getItemViewType(position); if (convertView == null) { //设置布局和找ID switch (type) { case TYPE_1: convertView = View.inflate(ctx, R.layout.adapter, null); holder1 = new MyViewHolder(convertView); convertView.setTag(holder1); break; case TYPE_2: convertView = View.inflate(ctx, R.layout.adapter2, null); holder2 = new MyViewHolder2(convertView); convertView.setTag(holder2); break; case TYPE_3: convertView = View.inflate(ctx, R.layout.adapter3, null); holder3 = new MyViewHolder3(convertView); convertView.setTag(holder3); break; } } else { //设置复用 switch (type) { case TYPE_1: holder1 = (MyViewHolder) convertView.getTag(); break; case TYPE_2: holder2 = (MyViewHolder2) convertView.getTag(); break; case TYPE_3: holder3 = (MyViewHolder3) convertView.getTag(); break; } } //设置数据 switch (type) { case TYPE_1: break; case TYPE_2: break; case TYPE_3: break; } return convertView; } private class MyViewHolder { public MyViewHolder(View convertView) { } } private class MyViewHolder2 { public MyViewHolder2(View convertView) { } } private class MyViewHolder3 { public MyViewHolder3(View convertView) { } }} MainActivity.java
public class MainActivity extends AppCompatActivity { RecyclerView mRecy; ListView mLv; List mList = new ArrayList<>(); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initList(); initView(); } private void initList() { for (int i = 0; i < 100; i++) { mList.add(i); } } private void initView() { mRecy = findViewById(R.id.mRecy); mLv = findViewById(R.id.mLv); // mRecy.setLayoutManager(new LinearLayoutManager(this)); // mRecy.setAdapter(new MyAdapter(this, mList)); mLv.setAdapter(new MyAdapter2(mList,this)); }} 效果图：
扩展文章：RecyclerView仿今日头条新闻列表多item实现
更多相关文章
- 可左右两侧挤压傍边布局的Android抽屉
- 老罗的Android视频教程整理之常用布局
- android开发动态页面时常用的LayoutInflater实例化的三种方式
- Android中的布局方式（一）
- win10下使用Fiddler进行网络抓包
- android 属性系统，SystemProperties 的简介
- Android绘图机制（三） ViewGroup类的延伸
- Android(安卓)TextView字体样式设置
- android 下使用GPS 无法获取经纬度的解决方法