最佳答案
如何更新RecyclerView适配器数据
我试图弄清楚更新RecyclerView的适配器的问题是什么。
在我得到一个新的产品清单后，我试着:
从创建
recyclerView的片段中更新ArrayList，将新数据设置为适配器，然后调用adapter.notifyDataSetChanged();这并没有起作用。创建一个新的适配器，就像其他人做的那样，它为他们工作，但对我来说没有任何变化:
recyclerView.setAdapter(new RecyclerViewAdapter(newArrayList))- 在
Adapter中创建一个更新数据的方法，如下所示:public void updateData(ArrayList<ViewModel> viewModels) { items.clear(); items.addAll(viewModels); notifyDataSetChanged(); }然后每当我想要更新数据列表时，我就调用这个方法;这并没有起作用。
检查我是否可以修改recyclerView以任何方式，我尝试删除至少一个项目:
public void removeItem(int position) { items.remove(position); notifyItemRemoved(position); }
一切都保持原样。
这是我的适配器:
public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder> implements View.OnClickListener {
private ArrayList<ViewModel> items;
private OnItemClickListener onItemClickListener;
public RecyclerViewAdapter(ArrayList<ViewModel> items) {
this.items = items;
}
public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
this.onItemClickListener = onItemClickListener;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_recycler, parent, false);
v.setOnClickListener(this);
return new ViewHolder(v);
}
public void updateData(ArrayList<ViewModel> viewModels) {
items.clear();
items.addAll(viewModels);
notifyDataSetChanged();
}
public void addItem(int position, ViewModel viewModel) {
items.add(position, viewModel);
notifyItemInserted(position);
}
public void removeItem(int position) {
items.remove(position);
notifyItemRemoved(position);
}
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
ViewModel item = items.get(position);
holder.title.setText(item.getTitle());
Picasso.with(holder.image.getContext()).load(item.getImage()).into(holder.image);
holder.price.setText(item.getPrice());
holder.credit.setText(item.getCredit());
holder.description.setText(item.getDescription());
holder.itemView.setTag(item);
}
@Override
public int getItemCount() {
return items.size();
}
@Override
public void onClick(final View v) {
// Give some time to the ripple to finish the effect
if (onItemClickListener != null) {
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
onItemClickListener.onItemClick(v, (ViewModel) v.getTag());
}
}, 0);
}
}
protected static class ViewHolder extends RecyclerView.ViewHolder {
public ImageView image;
public TextView price, credit, title, description;
public ViewHolder(View itemView) {
super(itemView);
image = (ImageView) itemView.findViewById(R.id.image);
price = (TextView) itemView.findViewById(R.id.price);
credit = (TextView) itemView.findViewById(R.id.credit);
title = (TextView) itemView.findViewById(R.id.title);
description = (TextView) itemView.findViewById(R.id.description);
}
}
public interface OnItemClickListener {
void onItemClick(View view, ViewModel viewModel);
}
}
并且我像下面这样初始化RecyclerView:
recyclerView = (RecyclerView) view.findViewById(R.id.recycler);
recyclerView.setLayoutManager(new GridLayoutManager(getActivity(), 5));
adapter = new RecyclerViewAdapter(items);
adapter.setOnItemClickListener(this);
recyclerView.setAdapter(adapter);
那么，如何实际更新适配器数据以显示新接收到的项呢?
问题是gridView的布局是这样的:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:tag="catalog_fragment"
android:layout_height="match_parent">
<FrameLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipToPadding="false"/>
<ImageButton
android:id="@+id/fab"
android:layout_gravity="top|end"
style="@style/FabStyle"/>
</FrameLayout>
</LinearLayout>
然后我删除了LinearLayout，并将FrameLayout作为父布局。
