更新Recyclerview的項目數

Question

我正在嘗試在我的應用程序中實現搜索功能，但是我遇到了問題。

例如，當我搜索黃色花朵時，我發現200個結果，我將200個存儲在NumberWalls變量中，以使適配器在RecyclerView僅顯示200個項目，並且一切正常，我的問題是當我搜索例如Google Picture時找到4個結果，當我再次搜索黃色花朵時，我在RecyclerView上只看到4個項目，而不是200個。

 private void setAdapterForRecyclerView(List<Wallpaper> wlls, int NumberWalls) {

        if (myAdapter == null) {
            errortv.setVisibility(View.GONE);
            myAdapter = new MyAdapterSearch(wlls, getApplicationContext(), new RecyclerViewClickListener() {
                @Override
                public void onClick(View view, Wallpaper wallpaper) {
                    Intent intent = new Intent(Search.this, FullScreen.class);
                    intent.putExtra("img", wallpaper.getThumbnails());
                    intent.putExtra("tags", wallpaper.getTitle());
                    startActivity(intent);
                }

                @Override
                public void onClick(View view, Category categories) {

                }
            }, (NumberWalls));
            recyclerView.setAdapter(myAdapter);

        } else {
            int position = myAdapter.getItemCount();
            myAdapter.getItems().addAll(wlls);
            myAdapter.notifyItemRangeInserted(position, NumberWalls);
        }
        progressbar.setVisibility(View.GONE);
    }

在適配器中：

public MyAdapterSearch(List<Wallpaper> wallpapers, Context context, RecyclerViewClickListener clickListener, int numberItem) {
        this.wallpapers = wallpapers;
        this.context = context;
        this.mClickListener = clickListener;
        this.numberItem = numberItem;
    }
    .
    .
    .

@Override
    public int getItemCount() {
        return Math.min(wallpapers.size(), numberItem);
    }

這是我獲取NumberWalls的AsyncTask類：

public class fetchDataSearch extends AsyncTask<Integer, List<Wallpaper>, List<Wallpaper>> {
        Document doc = null;
        ArrayList<Wallpaper> urlsSearch = new ArrayList<>();
        String numberOnly;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }

        @Override
        protected List<Wallpaper> doInBackground(Integer... integers) {
            try {
                doc = Jsoup.connect(getResources().getString(R.string.SearchRequest) + mSearchText.replace(" ", "+") + "&page=" + integers[0]).get();
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (doc != null) {
                Element noResultfound = doc.getElementsByClass("notice notice-error").first();
                if (noResultfound != null) {
                    noResultsFoundCatched = true;
                } else {
                    Element element = doc.select("div.center > h1").first();
                    numberOnly = element.text().replaceFirst(".*?(\\d+).*", "$1");
                    Elements newsHeadlines = doc.getElementsByClass("img-responsive");
                    for (Element headline : newsHeadlines) {
                        String thumb = headline.select("img").attr("src");
                        String title = headline.select("img").attr("title");
                        Wallpaper wallpaperInfo = new Wallpaper();
                        wallpaperInfo.setThumbnails(thumb);
                        wallpaperInfo.setTitle(title);
                        if (BooleanChecker.checkTagsContains(title)) {
                            urlsSearch.add(wallpaperInfo);
                        } else {
                            unWantedTagsFound++;
                        }
                    }
                    noResultsFoundCatched = false;
                }

            } else {
                noResultsFoundCatched = true;
            }
            return urlsSearch;
        }

        @Override
        protected void onPostExecute(List<Wallpaper> wallpapersSearch) {
            super.onPostExecute(wallpapersSearch);
            if (numberOnly != null) {
                numberWallpapersPage = Integer.parseInt(numberOnly);
                setAdapterForRecyclerView(wallpapersSearch, numberWallpapers);
            } 
        }
    }

Answer 1

我認為您可以刪除numberItem東西，而讓getItemCount()僅僅返回wallpapers.size() 。 因為，您要為適配器提供搜索返回的壁紙列表，所以我猜您想在列表中顯示所有壁紙。

另外，在更新適配器時，無需將搜索結果添加到項目列表中，只需將結果設置為項目即可。

myAdapter.setWallpapers(wlls);

並將方法setWallpapers()添加到適配器：

public void setWallpapers(List<Wallpaper> wallpapers) {
    this.wallpapers = wallpapers;
    notifyDatasetChanged();
}