如何在初始化 recyclerview 适配器时保持 UI 解锁？

Question

如何在不锁定 UI 的情况下初始化 RecyclerView 适配器？ 我要做的就是在创建适配器视图时显示进度条，完成该操作后隐藏进度条并显示完成的 recyclerview 适配器。

问题是当 i .setAdapter() 时，UI 会冻结一小会儿，并且进度条会在那一刻冻结。

我不知道如何解决这个问题，因为视图相关的操作必须在 UI 线程中完成。

有什么想法吗？

代码： 从 db 加载数据：

dataLoader = Observable
                .just(getApplication().getDbHelper())
                .map(this::doInBackground)
                .subscribeOn(Schedulers.io())
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(this::onPostExecute);

onPostExecute 方法：

entriesAdapter = new EntriesAdapter(getApplication(), loadedData.entries);
this.loadedData = loadedData;
RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getContext());
        viewHolder.entries.setHasFixedSize(true);
        viewHolder.entries.setLayoutManager(layoutManager);
        viewHolder.entries.setItemAnimator(new DefaultItemAnimator());
        viewHolder.entries.setAdapter(entriesAdapter);

适配器代码：

public class EntriesAdapter extends RecyclerView.Adapter<EntriesAdapter.ViewHolder> {
    private BudgeterApplication app;
    private List<Expense> entries;
    private CompositeDisposable compositeDisposable;

    public EntriesAdapter(BudgeterApplication app, List<Expense> entries) {
        this.app = app;
        this.entries = entries;
    }

    public void setEntries(List<Expense> entries) {
        this.entries = entries;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
        return new ViewHolder(LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.expense_list_row, viewGroup, false));
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder viewHolder, int i) {
        Expense expense = entries.get(i);

        viewHolder.getSumText().setText(BigDecimalUtils.convertToCurrencyString(expense.getSum()));
        viewHolder.getCommentText().setText(expense.getComment() == null ? "" : expense.getComment());
        viewHolder.getDateText().setText(DateUtils.convertToString(expense.getTimeStamp(), "MM-dd HH:mm"));
    }

    @Override
    public void onAttachedToRecyclerView(@NonNull RecyclerView recyclerView) {
        compositeDisposable = new CompositeDisposable();
        super.onAttachedToRecyclerView(recyclerView);
    }

    @Override
    public void onDetachedFromRecyclerView(@NonNull RecyclerView recyclerView) {
        if (compositeDisposable != null && !compositeDisposable.isDisposed()) {
            compositeDisposable.dispose();
        }
        super.onDetachedFromRecyclerView(recyclerView);
    }

    @Override
    public int getItemCount() {
        return entries.size();
    }


    @Getter
    class ViewHolder extends RecyclerView.ViewHolder {

        private View parent;
        private TextView sumText;
        private TextView commentText;
        private TextView dateText;

        ViewHolder(@NonNull View itemView) {
            super(itemView);
            this.parent = itemView;
            init();
        }

        private void init() {
            sumText = parent.findViewById(R.id.sum_text);
            commentText = parent.findViewById(R.id.comment_text);
            dateText = parent.findViewById(R.id.date_text);
        }
    }
}

Answer 1

看起来您在构建 RecycerView 项目时可能进行了太多繁重的处理。

另外，请务必设置回收站视图recyclerView.setHasFixedSize(true)的此属性

如果这没有帮助，我建议在这里查看最简单的示例https://developer.android.com/guide/topics/ui/layout/recyclerview

这可以正常工作，因此您可以将其与您的代码进行比较