试图弄清楚update RecyclerView的Adapter 是什么问题。
获得新的产品列表后，我尝试：
ArrayList从recyclerView创建的片段更新，将新数据设置为adapter，然后调用adapter.notifyDataSetChanged(); 它不起作用。像其他人一样创建一个新适配器，它对他们有用，但是对我来说没有任何变化：
recyclerView.setAdapter(new RecyclerViewAdapter(newArrayList))创建一种
Adapter如下更新数据的方法：public void updateData(ArrayList<ViewModel> viewModels) { items.clear(); items.addAll(viewModels); notifyDataSetChanged(); }然后，无论何时要更新数据列表，我都调用此方法。它不起作用。
要检查我是否可以以任何方式修改recyclerView，并尝试至少删除一个项目：
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);
}
}我开始RecyclerView如下：
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目？
更新：问题是gridView的布局如下所示：
<?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>然后我只是删除LinearLayout并FrameLayout作为父布局。
@ miha-x64你是对的-它将不那么难看。问题在于这根本行不通。适配器没有引用该引用。它获取引用本身。因此，如果您构建一个新的数据集，则它具有一个新的引用，而适配器仍然只知道旧的引用。
—
令人难以置信的
items.clear(); items.addAll(newItems);是一个丑陋的模式。如果您确实需要在此处进行防御性复制，items = new ArrayList(newItems);则将不再那么难看。