GridView的滚动速度在停止时很慢

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在我当前应用程序的一个片段中，listview中有三个列表，每个列表显示一个GridView，在GridView中有大约8到15个imageViews作为项目。所以我创建适配器A和适配器B.适配器A充当ListView和表示ListView和每个GridView的标题的字符串之间的桥梁。适配器B连接GridView及其ImageView（8~15）。因此，在适配器A的getView方法中，我插入了创建适配器B并连接到相应gridView的代码。从适配器中调用适配器的原因（当然我个人的猜测）是数据和图像很好地连接到gridView，即使它连接到ListView，GridView的滚动速度也很慢好像滚动停止了。

我的问题是

1]我想知道为什么gridView的滚动速度在停止时很慢。

  • 就个人而言，我认为这不是因为图像的大小。 （这是因为GridView的滚动速度与图像输入图像视图之前的滚动速度完全相同。）

2]解决方案是什么？

  • 我尝试使用AsyncTask加载图像。但我的图像是在一个drawable文件夹（int变量），我不知道如何加载它们（例如，int mimageResource = R.drawable.image）尝试时，图像仍然有空图像项目当GridView打开时， GridView的速度在那时很相似，所以我想知道AsyncTask是否是一个解决方案。

我非常感谢你的建议。

---------------------------这些是我的代码------------------- --------------

1] SiteAdapter.java（链接gridview和item）

public class SiteAdapter extends ArrayAdapter<Site> {
private Site currentSite;
private final int REQUEST_WIDTH = 256;
private final int REQUEST_HEIGHT = 256;
public Context context;


public SiteAdapter(Context context, ArrayList<Site> sites) {
    super(context, 0, sites);
    this.context = context;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    View listItemView = convertView;
    SiteViewHolder viewHolder;
    if(listItemView == null){
        listItemView = LayoutInflater.from(getContext()).inflate(R.layout.list_item, parent,false);

        viewHolder = new SiteViewHolder();
        viewHolder.icon = (ImageView) listItemView.findViewById(R.id.image);
        viewHolder.icon_name = (TextView) listItemView.findViewById(R.id.name);

        listItemView.setTag(viewHolder);
    }
    else
        viewHolder = (SiteViewHolder) listItemView.getTag();

    currentSite = getItem(position);
    viewHolder.position = position;

    //new ThumbnailTask(position, viewHolder).execute((currentSite.getMsite_imagesource()));

    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(getContext().getResources(),currentSite.getMsite_imagesource(),options);
    options.inSampleSize = setSimpleSize(options, REQUEST_WIDTH, REQUEST_HEIGHT);
    options.inJustDecodeBounds = false;
    Bitmap bitmap = BitmapFactory.decodeResource(getContext().getResources(),currentSite.getMsite_imagesource(),options);


    viewHolder.icon.setBackground(new ShapeDrawable(new OvalShape()));
    viewHolder.icon.setClipToOutline(true);
    viewHolder.icon.setImageBitmap(bitmap);
    viewHolder.icon_name.setText(currentSite.getMsite_name());


    return listItemView;
}
private int setSimpleSize(BitmapFactory.Options options, int requestWidth, int requestHeight){
    int originalWidth = options.outWidth;
    int originalHeight = options.outHeight;

    int size = 1;

    while(requestWidth < originalWidth || requestHeight < originalHeight){
        originalWidth = originalWidth / 2;
        originalHeight = originalHeight / 2;

        size = size * 2;
    }
    return size;
}

2] ListAdapter（链接list_title（String），GridView到ListView）

public class ListAdapter extends BaseAdapter {

public Context mcontext;
public Hashtable<String, ArrayList<Site>> mdata;
public Map.Entry<String,ArrayList<Site>> copyData;
public ArrayList<String> keySet = new ArrayList<String>();
private String key;
private int num=0;
public String currentName;
private ArrayList<Site> currentSite;
private int [] count = {0,0,0};

public ListAdapter(Context context,Hashtable<String, ArrayList<Site>> data){
    mcontext = context;
    mdata = data;
    Iterator it = data.entrySet().iterator();
    while(it.hasNext()) {
        copyData = (Map.Entry<String, ArrayList<Site>>) it.next();
        keySet.add(copyData.getKey());
    }
}

public String getKey(int position){
    //Iterator it = mdata.entrySet().iterator();
    //copyData = (Map.Entry<String, ArrayList<Site>>) it.next();
    return keySet.get(position);
}

@Override
public int getCount() {
    /*Iterator it = mdata.entrySet().iterator();
    while(it.hasNext())
    {
        num++;
    }
    return num;*/
    return keySet.size();
}

@Override
public ArrayList<Site> getItem(int position) {
    return mdata.get(keySet.get(position));
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(final int position, final View convertView, final ViewGroup parent) {
    View view = convertView;
    final ArrayList<Site> currentSite;
    ListViewHolder holder;

    if(view == null) {
        view = LayoutInflater.from(mcontext).inflate(R.layout.site_list, parent, false);

        holder = new ListViewHolder();
        holder.list_title = (TextView) view.findViewById(R.id.title_site_list);
        holder.lists = (GridView) view.findViewById(R.id.gridView);

        view.setTag(holder);
    }

    else
        holder = (ListViewHolder) view.getTag();

    currentName = keySet.get(position);
    holder.list_title.setText(currentName);

    currentSite = getItem(position);

    final SiteAdapter siteAdapter = new SiteAdapter(mcontext,currentSite);
    holder.lists.setAdapter(siteAdapter);

    final ViewSwitcher viewSwitcher = (ViewSwitcher) view.findViewById(R.id.visibility);
    holder.list_title.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if(count[position]%2==0){
                viewSwitcher.setVisibility(View.VISIBLE);
                viewSwitcher.showNext();
                count[position]++;
            }
            else if(count[position]%2==1){
                viewSwitcher.setVisibility(View.GONE);
                viewSwitcher.showNext();
                count[position]++;
            }
        }
    });

    holder.lists.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) {
            final Site site = currentSite.get(position);
            if (site.getMsite_name() == "Gist home") {
                PopupMenu popupIFWB = new PopupMenu(mcontext.getApplicationContext(), view);

                popupIFWB.getMenuInflater().inflate(R.menu.insta_facebook_web_blog_popup_menu, popupIFWB.getMenu());
                popupIFWB.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
                    @Override
                    public boolean onMenuItemClick(MenuItem menuItem) {
                        switch (menuItem.getItemId()) {
                            case R.id.webIFWB:
                                openWebPage(site.getMsite_urlW());
                                break;
                            case R.id.blogIFWB:
                                openWebPage(site.getMsite_urlB());
                                break;
                            case R.id.facebookIFWB:
                                openWebPage(site.getMsite_urlF());
                                break;
                            case R.id.instaIFWB:
                                openWebPage(site.getMsite_urlI());
                                break;
                        }
                        return false;
                    }
                });
                popupIFWB.show();
            } else
                openWebPage(site.getMsite_url());
        }

    });
    return view;
}

private static class ListViewHolder{
    public TextView list_title;
    public GridView lists;
}

public void openWebPage(String url){
    Uri webpage = Uri.parse(url);
    Intent siteMove = new Intent(Intent.ACTION_VIEW, webpage);
    if(siteMove.resolveActivity(mcontext.getPackageManager()) != null)
        mcontext.startActivity(siteMove);
}

}

3] OfficialFragment.java（和家一样）

public class OfficialFragment extends Fragment {


private int count = 0;
private ArrayList<String> arrayGroup = new ArrayList<String>();
private Hashtable<String, ArrayList<Site>> arrayChild = new Hashtable<String, ArrayList<Site>>();

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    final View viewMain = inflater.inflate(R.layout.listview, null);
    super.onCreate(savedInstanceState);
    ListView listView = (ListView) viewMain.findViewById(R.id.listView);

    //GridView gridView = (GridView) viewMain.findViewById(R.id.gridView);
    setArrayData();

    ListAdapter listAdapter = new ListAdapter(getActivity(),arrayChild);
    listView.setAdapter(listAdapter);

    return viewMain;
}

public void openWebPage(String url){
    Uri webpage = Uri.parse(url);
    Intent siteMove = new Intent(Intent.ACTION_VIEW, webpage);
    if(siteMove.resolveActivity(getActivity().getPackageManager()) != null)
        startActivity(siteMove);
}

public void setArrayData(){

    arrayGroup.add("공식 사이트 모음");
    arrayGroup.add("조직 사이트 모음");
    arrayGroup.add("동아리 사이트 모음");

    ArrayList<Site> arrayOfficial = new ArrayList<Site>();
    arrayOfficial.add(new Site("Gist home", "https://www.gist.ac.kr/kr/","https://blog.naver.com/gist1993","https://www.facebook.com/GIST.ac.kr/","https://www.instagram.com/gist1993/", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("Zeus system", "https://zeus.gist.ac.kr", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("Portal system", "https://portal.gist.ac.kr/intro.jsp", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("Email system", "https://mail.gist.ac.kr/loginl?locale=ko_KR", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("Gist college", "https://college.gist.ac.kr/", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("Gist library", "https://library.gist.ac.kr/", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("학내공지", "https://college.gist.ac.kr/main/Sub040203", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("GIST 창업진흥센터", "https://www.facebook.com/gistbi/?ref=py_c", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("전기전자컴퓨터공학부", "http://eecs.gist.ac.kr/", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("신소재공학부", "http://mse.gist.ac.kr", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("기계공학부", "http://me.gist.ac.kr", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("지구·환경공학부", "http://env1.gist.ac.kr", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("생명과학부", "http://life1.gist.ac.kr", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("물리·광과학과", "http://phys.gist.ac.kr/", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("화학과", "http://chem.gist.ac.kr", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("융합기술원", "http://iit.gist.ac.kr", R.drawable.ic_dashboard_black_24dp));
    arrayOfficial.add(new Site("나노바이오재료전자공학과", "http://wcu.gist.ac.kr/", R.drawable.ic_dashboard_black_24dp));

    ArrayList<Site> arrayOrganization = new ArrayList<Site>();
    arrayOrganization.add(new Site("Gist 총학생회", "https://www.facebook.com/gistunion/", R.drawable.gistunion));
    arrayOrganization.add(new Site("Gist 동아리연합회", "https://www.facebook.com/gistclubunite/", R.drawable.clubnight));
    arrayOrganization.add(new Site("Gist 하우스", "https://www.facebook.com/GISTcollegeHOUSE/", R.drawable.gisthouse));
    arrayOrganization.add(new Site("Gist 문화행사위원회", "https://www.facebook.com/Moonhangwe/", R.drawable.moonhangwe));
    arrayOrganization.add(new Site("Gist 신문","http://gistnews.co.kr/", "https://www.facebook.com/pg/GistSinmoon/posts/", R.drawable.gistnews));
    arrayOrganization.add(new Site("Gist 홍보대사", "http://blog.naver.com/PostList.nhn?blogId=gist1993&from=postList&categoryNo=28", R.drawable.gionnare));

    ArrayList<Site> arrayCircle = new ArrayList<Site>();
    arrayCircle.add(new Site("영화 동아리 Cinergy", "https://www.facebook.com/gistcinergy/", R.drawable.cinergy));
    arrayCircle.add(new Site("영상편집 동아리 The Gist", "https://www.facebook.com/Gentletist/","https://www.youtube.com/channel/UCMUDHS0SZvQilFe5h6eI9rA/videos", R.drawable.thegist));
    arrayCircle.add(new Site("문예창작 동아리 사각사각", "https://www.facebook.com/GIST-%EC%82%AC%EA%B0%81%EC%82%AC%EA%B0%81-238788459851229/", R.drawable.sagaksagak));
    arrayCircle.add(new Site("gist 고양이 지냥이", "https://www.facebook.com/giscats/", R.drawable.giscat));
    arrayCircle.add(new Site("요리동아리 이쑤시개", "https://www.facebook.com/%EC%9D%B4%EC%91%A4%EC%8B%9C%EA%B0%9C-%EC%9A%94%EB%A6%AC%ED%95%98%EB%8A%94-GIST%EC%83%9D-272551203239747/?ref=py_c", R.drawable.essosigae));
    arrayCircle.add(new Site("칵테일 동아리 MixoloGIST", "https://www.facebook.com/Mixologist-1584231725157207", R.drawable.mixologist));
    arrayCircle.add(new Site("보드게임 동아리 BGM", "https://www.facebook.com/GISTBGM", R.drawable.bgm));
    arrayCircle.add(new Site("성소수자 모임 speQtrum", "https://www.facebook.com/gistspeqtrum/", R.drawable.speqtrum));
    arrayCircle.add(new Site("만화 동아리 erutlucbus", "https://www.facebook.com/Erutlucbus/", R.drawable.eru));
    arrayCircle.add(new Site("천체관측 동아리 SpaceBar", "https://www.facebook.com/GISTspacebar/", R.drawable.spacebar));
    arrayCircle.add(new Site("전산 동아리 WING", "https://www.facebook.com/GISTWING/", R.drawable.wing));
    arrayCircle.add(new Site("환경 동아리 온새미로", "https://www.facebook.com/onsaemiro123/", R.drawable.onsaemiro));
    arrayCircle.add(new Site("축구 동아리 Kickass", "https://www.facebook.com/gistkickass/?ref=br_rs", R.drawable.kickass));

    arrayChild.put(arrayGroup.get(0),arrayOfficial);
    arrayChild.put(arrayGroup.get(1),arrayOrganization);
    arrayChild.put(arrayGroup.get(2),arrayCircle);

}

}

4] SiteHolder.java（ViewHolder包含GridView项）

public class SiteViewHolder {
public ImageView icon;
public TextView icon_name;
public int position;
}
答案

没有任何代码，很难帮助你。但是，您必须拆分“加载”和“显示”过程。您的适配器应仅保存/显示文本/数字数据，并将图像保留为空/空。然后在“Adapter.getView（）”中你必须创建一个AsyncTask，它从你的drawable文件夹中提取图像（在它的“doInBackground（）”方法中添加它），然后把它放在相对的ImageView中（在它的“在ListView的右行位置的onPostExecute（）“方法”。

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