时间戳

首页 > 解决方案 > 如何在 ScrollUp 上清除 RecyclerView 中的列表

android - 如何在 ScrollUp 上清除 RecyclerView 中的列表

问题描述

我想用 Rest Api 和 Retrofit 制作应用程序。我想在用户拉下 RecyclerView 时加载随机帖子，但当我加载随机帖子时，我做到了但一件很烦人的事情。它显示在前 10 个帖子之后，我的意思是在主页的 10 个帖子之后，但我想清除旧帖子并显示第 1 行的随机帖子。

我用于向上滚动的代码

 else if (!recyclerView.canScrollVertically(-1) && dy < 0)
            {


                        yourURL1 = baseURL + baseModel + "&orderby=rand&page=" + pageNo++;
                        getRetrofit1();



            }

改造

try {
        List<Model> list = new ArrayList<>();
        Call<List<WPPost>>  call = service.getPostInfo( yourURL);
        call.enqueue(new Callback<List<WPPost>>() {
            @Override
            public void onResponse(Call<List<WPPost>> call, Response<List<WPPost>> response) {
                Log.d("==>>", " response "+ response.body());
                mListPost = response.body();
                progressBar.setVisibility(View.GONE);
                if (response.body() != null) {
                    for (int i = 0; i < response.body().size(); i++ ) {
                        Log.d("==>>", " title " + response.body().get(i).getTitle().getRendered() + " " +
                                response.body().get(i).getId());
                        String tempdetails = String.valueOf((Html.fromHtml(response.body().get(i).getExcerpt().getRendered().toString())));
                        tempdetails = tempdetails.replace("<p>", "");
                        tempdetails = tempdetails.replace("</p>", "");
                        tempdetails = tempdetails.replace("[&hellip;]", "");
                        list.add(new Model(String.valueOf((Html.fromHtml(response.body().get(i).getTitle().getRendered()))),
                                tempdetails, response.body().get(i).getPostViews().toString(),
                                response.body().get(i).getImages().getMedium(),response.body().get(i).getContent().getRendered()));

                    }
                    if (loading){
                        loading = false;
                        adapter.showHideProgress(false);
                    }
                    adapter.addItemsToList(list);
                    progressBar.setVisibility(View.GONE);
                } else {
                    progressBar.setVisibility(View.GONE);
                }
            }
            @Override
            public void onFailure(Call<List<WPPost>> call, Throwable t) {
            }
        });

    }catch (Exception exception){
        Log.d("tisha==>>"," "+exception.getLocalizedMessage());
    }

在适配器中

 void addItemsToList(List<Model> newItems){
    if (dataset.isEmpty()){
        dataset.addAll(newItems);
        notifyDataSetChanged();
        Log.d("tisha==>>","First time List size = "+dataset.size());
    }else {
        int lastItemPosition = dataset.size() -1;
        Log.d("tisha==>>","Old list size = "+dataset.size()+ "Last Item position= "+lastItemPosition);
        dataset.addAll(newItems);
        Log.d("tisha==>>","Update List size = "+dataset.size());
        notifyItemRangeInserted(lastItemPosition,newItems.size());
    }
}

我怎样才能清除列表？

标签： androidlistviewarraylistandroid-recyclerview

解决方案

once this list is set you are adding items to list , you have to remove elements first notify item ranged removed then add new and update on notify item inserted   
 
void addItemsToList(List<Model> newItems)
{ if (dataset.isEmpty())
{ dataset.addAll(newItems); 
notifyDataSetChanged(); 
Log.d("tisha==>>","First time List size = "+dataset.size());
 }
else 
{ 
int lastItemPosition = dataset.size() -1; 
Log.d("tisha==>>","Old list size = "+dataset.size()+ "Last Item position= "+lastItemPosition); dataset.addAll(newItems);
 Log.d("tisha==>>","Update List size = "+dataset.size()); notifyItemRangeInserted(lastItemPosition,newItems.size()); } }

推荐阅读