RV 数据刷新方式总结 局部刷新 模板代码
目录
目录
RV 数据刷新方式总结 局部刷新 模板代码
数据刷新方式总结 局部刷新
- 刷新全部可见的item，notifyDataSetChanged()
- 刷新指定item，notifyItemChanged(int)
- 从指定位置开始刷新指定个item，notifyItemRangeChanged(int,int)
- 插入、移动一个并自动刷新，notifyItemInserted(int)、notifyItemMoved(int)、notifyItemRemoved(int)
- 局部刷新，notifyItemChanged(int, Object)
Activity
public class Notify_Activity extends Activity implements MyOnItemClickLitener {
private RecyclerView mRecyclerView;
private Notify_Adapter mAdapter;
private ArrayList<PicUrls.BasicPicBean> beans;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
((SwipeRefreshLayout) findViewById(R.id.swipeLayout)).setEnabled(false);
mRecyclerView = (RecyclerView) findViewById(R.id.rv);
initList();
initView();
}
protected void initView() {
mAdapter = new Notify_Adapter(this, beans);
mAdapter.setOnItemClickLitener(this);
mRecyclerView.setAdapter(mAdapter);//设置adapter
mRecyclerView.setLayoutManager(new GridLayoutManager(this, 3));//设置布局管理器
mRecyclerView.setItemAnimator(new DefaultItemAnimator());//设置Item增加、移除动画
mRecyclerView.addItemDecoration(new GridItemDecoration.Builder().spanCount(3)
.spaceSize(1).mDivider(new ColorDrawable(0x88ff0000)).build());
}
private void initList() {
beans = PicUrls.getPicList(PicUrls.BIG_BEANS_2);
beans.get(0).name = "刷新当前，notifyItemChanged(int)";
beans.get(1).name = "全部刷新，notifyDataSetChanged()";
beans.get(2).name = "从此位置开始刷新2个，notifyItemRangeChanged";
beans.get(3).name = "插入一个并自动刷新，notifyItemInserted";
beans.get(4).name = "只更改数据源，这样当然不会刷新UI";
beans.get(5).name = "插入一个并刷新当前，notifyItemChanged";
beans.get(6).name = "局部刷新，tv";
beans.get(7).name = "局部刷新，et";
beans.get(8).name = "局部刷新，iv";
}
@Override
public void onItemClick(View view, int position) {
Toast.makeText(this, position + " 被点击了", Toast.LENGTH_SHORT).show();
reInit(position);
}
@Override
public void onItemLongClick(View view, int position) {
Toast.makeText(this, position + "被长按了", Toast.LENGTH_SHORT).show();
}
private void reInit(int position) {
switch (position) {
default:
mAdapter.notifyItemChanged(position);//刷新指定一个。一定会闪
break;
case 1:
mAdapter.notifyDataSetChanged();//全部刷新。基本不会闪，刚开始个别可能会闪
break;
case 2:
mAdapter.notifyItemRangeChanged(position, 2);//从指定位置开始刷新指定个。一定会闪
break;
case 3:
beans.add(position, new PicUrls.BasicPicBean("http://img.mmjpg.com/2015/74/1.jpg", "新插入的图片1", 1));
mAdapter.notifyItemInserted(position);//插入一个并刷新，正常
break;
case 4://只更改数据源，这样当然不会刷新UI
beans.add(position, new PicUrls.BasicPicBean("http://img.mmjpg.com/2015/74/2.jpg", "新插入的图片2", 2));
break;
case 5://
beans.add(position, new PicUrls.BasicPicBean("http://img.mmjpg.com/2015/74/3.jpg", "新插入的图片3", 3));
mAdapter.notifyItemChanged(position);//这样只会导致当前item刷新，而不会刷新其他item，当然是不行的
break;
case 6:
beans.set(position, beans.get(new Random().nextInt(beans.size())));
mAdapter.notifyItemChanged(position, Notify_Adapter.NOTIFY_TV);//局部刷新
break;
case 7:
beans.set(position, beans.get(new Random().nextInt(beans.size())));
mAdapter.notifyItemChanged(position, Notify_Adapter.NOTIFY_ET);//局部刷新
break;
case 8:
beans.set(position, beans.get(new Random().nextInt(beans.size())));
mAdapter.notifyItemChanged(position, Notify_Adapter.NOTIFY_IV);//局部刷新
break;
}
}
}
Adapter
public class Notify_Adapter extends RecyclerView.Adapter<Notify_Adapter.MyViewHolder> {
private Context context;
private List<PicUrls.BasicPicBean> mDatas;
private MyOnItemClickLitener mOnItemClickLitener;
public static final int NOTIFY_TV = 10086;
public static final int NOTIFY_ET = 10087;
public static final int NOTIFY_IV = 10088;
public Notify_Adapter(Context context, List<PicUrls.BasicPicBean> mDatas) {
this.context = context;
this.mDatas = mDatas;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new MyViewHolder(LayoutInflater.from(context).inflate(R.layout.item_notify, parent, false));
}
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
//不使用
}
@Override
public void onBindViewHolder(final MyViewHolder holder, int position, List payloads) {
//payloads是从notifyItemChanged(int, Object)中，或从notifyItemRangeChanged(int, int, Object)中传进来的Object集合
//如果payloads不为空并且viewHolder已经绑定了旧数据了，那么adapter会使用payloads参数进行布局刷新
//如果payloads为空，adapter就会重新绑定数据，也就是刷新整个item
PicUrls.BasicPicBean bean = mDatas.get(holder.getAdapterPosition());
long time = System.currentTimeMillis() + bean.url.hashCode();
String data = new SimpleDateFormat("HH:mm:ss", Locale.getDefault()).format(new Date(time));
if (payloads.isEmpty()) {//为空，即不是调用notifyItemChanged(position,payloads)后执行的，也即在初始化时执行的
holder.tv.setText(data);
holder.et.setText(bean.name);
Glide.with(context).load(bean.url)
.dontAnimate()
//.diskCacheStrategy(DiskCacheStrategy.NONE).skipMemoryCache(true)
.into(holder.iv);
} else if (payloads.size() > 0 && payloads.get(0) instanceof Integer) {
//不为空，即调用notifyItemChanged(position,payloads)后执行的，可以在这里获取payloads中的数据进行局部刷新
int type = (int) payloads.get(0);// 刷新哪个部分 标志位
switch (type) {
case NOTIFY_TV:
holder.tv.setText(data);//只刷新tv
break;
case NOTIFY_ET:
holder.et.setText(bean.name);//只刷新et
break;
case NOTIFY_IV:
Glide.with(context).load(bean.url).dontAnimate().into(holder.iv);//只刷新iv
break;
}
}
// 如果设置了回调，则设置点击事件
holder.itemView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
if (mOnItemClickLitener != null) mOnItemClickLitener.onItemClick(holder.itemView, holder.getAdapterPosition());
}
});
holder.itemView.setOnLongClickListener(new OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
if (mOnItemClickLitener != null) mOnItemClickLitener.onItemLongClick(holder.itemView, holder.getAdapterPosition());
return false;
}
});
}
@Override
public int getItemCount() {
return mDatas.size();
}
/**
* 添加并更新数据，同时具有动画效果
*/
public void addDataAt(int position, PicUrls.BasicPicBean data) {
mDatas.add(position, data);
notifyItemInserted(position);//更新数据集，注意如果用adapter.notifyDataSetChanged()将没有动画效果
}
/**
* 移除并更新数据，同时具有动画效果
*/
public void removeDataAt(int position) {
mDatas.remove(position);
notifyItemRemoved(position);
}
public void setOnItemClickLitener(MyOnItemClickLitener mOnItemClickLitener) {
this.mOnItemClickLitener = mOnItemClickLitener;
}
class MyViewHolder extends RecyclerView.ViewHolder {
TextView tv;
ImageView iv;
EditText et;
public MyViewHolder(View view) {
super(view);
tv = (TextView) view.findViewById(R.id.tv_name);
iv = (ImageView) view.findViewById(R.id.iv_head);
et = (EditText) view.findViewById(R.id.et_input);
}
}
}
布局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:orientation="vertical">
<TextView
android:id="@+id/tv_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
android:text="0.00"
android:textColor="#00f"
android:textSize="13sp"/>
<ImageView
android:id="@+id/iv_head"
android:layout_width="match_parent"
android:layout_height="200dp"
android:scaleType="centerCrop"
android:src="@mipmap/ic_launcher"/>
<EditText
android:id="@+id/et_input"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
android:hint="包青天"
android:inputType="numberDecimal"
android:labelFor="@id/et_input"
android:maxLines="1"
android:minWidth="50dp"
android:textColor="#f00"
android:textSize="10sp"/>
</LinearLayout>
模板代码
基础配置
implementation 'com.android.support:recyclerview-v7:27.1.1'
<android.support.v7.widget.RecyclerView
android:id="@+id/rv_group"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="5dp"/>
纯原生
Activity
mAdapter = new RecyclerAdapter(this, list);
mAdapter.setOnItemClickLitener(this);
RecyclerView recyclerView = findViewById(R.id.rv_group);
recyclerView.setLayoutManager(new LinearLayoutManager(mContext));
recyclerView.addItemDecoration(new DividerItemDecoration(mContext, DividerItemDecoration.VERTICAL));
recyclerView.setAdapter(mAdapter);
Adapter
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.MyViewHolder> {
private Context context;
private List<MyBean> mDatas;
private MyOnItemClickLitener mOnItemClickLitener;
public RecyclerAdapter(Context context, List<MyBean> mDatas) {
this.context = context;
this.mDatas = mDatas;
}
@NonNull
@Override
public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
return new MyViewHolder(LayoutInflater.from(context).inflate(R.layout.bea_item_recycle, parent, false));
}
@Override
public void onBindViewHolder(@NonNull final MyViewHolder holder, int position) {
holder.tv.setText(mDatas.get(position).name);
// 如果设置了回调，则设置点击事件
holder.itemView.setOnClickListener(v -> {
if (mOnItemClickLitener != null) mOnItemClickLitener.onItemClick(holder.itemView, holder.getAdapterPosition());
});
holder.itemView.setOnLongClickListener(v -> {
if (mOnItemClickLitener != null) mOnItemClickLitener.onItemLongClick(holder.itemView, holder.getAdapterPosition());
return false;
});
}
@Override
public int getItemCount() {
return mDatas.size();
}
public void setOnItemClickLitener(MyOnItemClickLitener mOnItemClickLitener) {
this.mOnItemClickLitener = mOnItemClickLitener;
}
class MyViewHolder extends RecyclerView.ViewHolder {
TextView tv;
public MyViewHolder(View view) {
super(view);
tv = view.findViewById(R.id.tv_name);
}
}
public interface MyOnItemClickLitener {
void onItemClick(View view, int position);
void onItemLongClick(View view, int position);
}
}
BaseRecyclerViewAdapterHelper
依赖
allprojects {
repositories {
...
maven { url "https://jitpack.io" }
}
}
compile 'com.github.CymChad:BaseRecyclerViewAdapterHelper:VERSION_CODE'
Adapter
public class MyAdapter extends BaseQuickAdapter<MyBean, BaseViewHolder> {
public MyAdapter(List<MyBean> datas) {
super(R.layout.bea_item_recycle, datas);
}
@Override
protected void convert(final BaseViewHolder helper, final MyBean item) {
helper.setText(R.id.tv_name, item.name);
}
}
Activity 中设置的点击事件
public class MyActivity implements BaseQuickAdapter.OnItemClickListener {
mAdapter.setOnItemClickListener(this);
@Override
public void onItemClick(BaseQuickAdapter adapter, View view, int position) {
}
}
点击事件可以通过如下几种方式设置：
mAdapter.setOnItemClickListener(new BaseQuickAdapter.OnItemClickListener() {});
mAdapter.setOnItemChildClickListener(new BaseQuickAdapter.OnItemChildClickListener() {});
mAdapter.setOnItemLongClickListener(new BaseQuickAdapter.OnItemLongClickListener() {});
mAdapter.setOnItemChildLongClickListener(new BaseQuickAdapter.OnItemChildLongClickListener() {});
水平或竖直分割线
compile 'com.yqritc:recyclerview-flexibledivider:1.4.0'
RecyclerView.ItemDecoration decor = new HorizontalDividerItemDecoration.Builder(mContext)//不能Horizontal**和Vertical**同时使用
.margin(SystemUtil.dp2px(15), SystemUtil.dp2px(2))//距离左右边界或上下边界的距离。也可以使用单参数的重载方法设定
.size(SystemUtil.dp2px(1))//水平线的高度或竖直线的宽度
.color(0xffe6e6e6)//间隔线的颜色。间隔线可以不使用颜色值而使用drawable方法指定drawable，同时使用时color()会把drawable()覆盖掉
.positionInsideItem(false)//间隔线是否绘制在item内容的上面(也即不会增加RecyclerView的高度或宽度)，默认为false
//.showLastDivider()//默认不显示最后一条间隔线，调用此方法则会显示示最后一条间隔线
.build();
其Builder中还有各种各级的用法
网格分割线
GridItemDecoration decoration = GridItemDecoration.newBuilder().spanCount(spanCount)
.horizontalDivider(new ColorDrawable(0xffff0000), 60, true)
.build();
GridItemDecoration decoration = GridItemDecoration.newBuilder().spanCount(spanCount)
.horizontalDivider(getResources().getDrawable(R.drawable.icon), 20, false)
.verticalDivider(new ColorDrawable(0xffff0000), 60, true)
.build();
2017-6-7
本文来自博客园，作者：白乾涛，转载请注明原文链接：https://www.cnblogs.com/baiqiantao/p/6956425.html
