RecyclerView简单记录

前言

简单记录一下RecyclerView的使用，记录于此方便自己查阅。

正文

这里只是简单记录一下。

xml

<androidx.recyclerview.widget.RecyclerView    android:id="@+id/list_rv_view"    android:layout_width="1000dp"    android:layout_height="600dp"    android:layout_weight="1" />

java

ItemAdapter

适配器

public class MediaAdapter extends RecyclerView.Adapter<MediaAdapter.ViewHolder> {    private List<FileInfo> mList = new ArrayList<>();         @NonNull    @Override    public MediaAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {        return new ViewHolder(LayoutInflater.from(MediaApp.getContext()).inflate(R.layout.layout_item_media, parent, false));    } ​    @Override    public void onBindViewHolder(@NonNull MediaAdapter.ViewHolder holder, int position) {        if (getItemCount() > 0) {            //略        }    } ​    @Override    public int getItemCount() {        return mList.size();    } ​    @SuppressLint("NotifyDataSetChanged")    public void updateList(List<FileInfo> list) {        if (list == null || list.isEmpty()) {            mList.clear();        } else {            mList = new ArrayList<>(list);        }        notifyDataSetChanged();    } ​    public static class ViewHolder extends RecyclerView.ViewHolder {        private final ImageView mIvIcon;        private final TextView mTvName; ​        public ViewHolder(@NonNull View itemView) {            super(itemView);            mIvIcon = itemView.findViewById(R.id.item_iv_icon);            mTvName = itemView.findViewById(R.id.item_tv_name);        }    } }

LinearLayoutManager

private RecyclerView mRecyclerView; private LinearLayoutManager mLinearLayoutManager; ​ mRecyclerView = mRootView.findViewById(R.id.list_rv_view); ​ //线性垂直显示 mLinearLayoutManager = new LinearLayoutManager(MusicApp.getContext()); mLinearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL); mRecyclerView.addItemDecoration(new DividerItemDecoration(MusicApp.getContext(), DividerItemDecoration.VERTICAL)); mRecyclerView.setLayoutManager(mLinearLayoutManager); mRecyclerView.setAdapter(mItemAdapter);

GridLayoutManager

 mMediaAdapter = new MediaAdapter();  //一行6个  mRecyclerView.setLayoutManager(new GridLayoutManager(MediaApp.getContext(), 6));  mRecyclerView.setAdapter(mItemAdapter);

指定间距

需要重写RecyclerView.ItemDecoration

public class SpacesItemDecoration extends RecyclerView.ItemDecoration {    private final int left, top, right, bottom; ​    public SpacesItemDecoration(int left, int top, int right, int bottom) {        this.left = left;        this.top = top;        this.right = right;        this.bottom = bottom;    } ​    @Override    public void getItemOffsets(Rect outRect, @NonNull View view, @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {        //看需求修改        outRect.bottom = bottom;        outRect.left = left;        outRect.right = right;        outRect.top = top;    } }

设置一下即可。

mRecyclerView.addItemDecoration(new SpacesItemDecoration(30, 30, 30, 30));

滚动指定位置

//position是指定位置 //方式一 mRecyclerView.scrollToPosition(position); //方式二 mLinearLayoutManager.scrollToPosition(position); //方式三 //position是指定位置 ，y是固定高度位置 mLinearLayoutManager.scrollToPositionWithOffset(position, y);

参考文章

1. 《个人常用的ListView方法简介》