前面我們見過ListView 使用 這里對(duì)比ListView 來學(xué)習(xí)RecyclerView。
首先RecyclerView也需要一個(gè)Adapter只是相對(duì)于之前的復(fù)雜一點(diǎn)點(diǎn)
這里使用了ViewHolder這個(gè)模式。
今天講講如何具體使用把
先看源碼
public class StoriesAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return null;
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
}
@Override
public int getItemCount() {
return 0;
}
}
首先繼承關(guān)系RecyclerView.Adapter<RecyclerView.ViewHolder>
這個(gè)類似我們之前的BaseAdapter
我們添加一個(gè)構(gòu)造方法,傳人一個(gè)list跟值錢的ListView的用法一樣
private List<StoryBean> mList;
private Context mContext;
public StoriesAdapter(Context context, ArrayList<StoryBean> list) {
this.mList = list;
this.mContext = context;
}
這樣寫是因?yàn)锳dapter一般都會(huì)關(guān)聯(lián)一個(gè)list這樣傳人是一個(gè)比較簡單的方式。
我們根據(jù)上面的代碼直接改造一個(gè)我們項(xiàng)目正在用的Adapter
public class StoriesAdapter extends RecyclerView.Adapter<StoriesAdapter.StoryViewHolder> {
private List<StoryBean> mList;
private Context mContext;
public StoriesAdapter(Context context, ArrayList<StoryBean> list) {
this.mList = list;
this.mContext = context;
}
//自定義的ViewHolder,持有每個(gè)Item的的所有界面元素
public static class StoryViewHolder extends RecyclerView.ViewHolder {
public TextView tv_story_title;
public ImageView iv_story;
public StoryViewHolder(View view) {
super(view);
tv_story_title = view.findViewById(R.id.tv_story_title);
iv_story = view.findViewById(R.id.iv_story);
}
}
@Override
public StoryViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.item_story, parent, false);
return new StoryViewHolder(view);
}
@Override
public void onBindViewHolder(StoryViewHolder holder, int position) {
StoryBean story = mList.get(position);
holder.tv_story_title.setText(mList.get(position).getTitle());
holder.iv_story.setImageResource(R.mipmap.one_piece);
// Glide.with(mContext).load(mList.get(position).getImages().get(0)).into(holder.iv_story);
}
@Override
public int getItemCount() {
return mList.size();
}
}
整個(gè)Adapter的源碼大概就是這個(gè)樣子了
看看如何使用把
RecyclerView mRecyclerView = (RecyclerView)findViewById(R.id.base_recycle);
//創(chuàng)建默認(rèn)的線性LayoutManager
LinearLayoutManager mLayoutManager = new LinearLayoutManager(this);
mRecyclerView.setLayoutManager(mLayoutManager);
//如果可以確定每個(gè)item的高度是固定的,設(shè)置這個(gè)選項(xiàng)可以提高性能
mRecyclerView.setHasFixedSize(true);
//創(chuàng)建并設(shè)置Adapter
StoryAdapter mAdapter = new StoryAdapter(mContext,list);
mRecyclerView.setAdapter(mAdapter);
}
這個(gè)就是簡單介紹下項(xiàng)目里如何RecyclerView ,現(xiàn)在沒有具體講解,對(duì)于新手,暫時(shí)先用listview 熟練之后,我會(huì)給出一個(gè)RecyclerView 的詳細(xì)使用方法的。暫時(shí)先不用看