Question

我正在为我的列表视图使用customadapter。在我的活动中，我有一些侦听器来标记选择的项目（第一次使用日志点击，然后短暂点击）在列表变得足够大以至于无法滚动之前，它一直有效。在这种情况下，如果我标记一个项目并向下滚动，那么也会标记其他项目，如果我快速滚动，标记的项目也会改变。我听说，ListView正在以某种方式回收这些位置，但我认为该位置应保持不变。

这是我的CustomAdapter ：（如果您也看到性能改进的一些可能性，请提及它）

public class CustomAdapterMain extends BaseAdapter {

private ArrayList<Kontakt> listItems;
private LayoutInflater layoutInflater;
private Kontakt kontakt;
private int position;
private ViewHolder viewHolder;
private Integer Kalenderjahr=Calendar.getInstance().get(Calendar.YEAR);
private Integer Kalendermonat=Calendar.getInstance().get(Calendar.MONTH);
private Integer Kalendertag=Calendar.getInstance().get(Calendar.DAY_OF_MONTH);
TinyDB tinyDB;

public CustomAdapterMain(Context context, ArrayList<Kontakt> arrayList){
    listItems=arrayList;
    //layoutInflater=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    layoutInflater=LayoutInflater.from(context);
    tinyDB= new TinyDB(context);
}

@Override
public int getCount() {
    return listItems.size();
}

@Override
public Kontakt getItem(int position) {
    return listItems.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}
@Override
public View getView(int position, View view, ViewGroup parent){
    if(view==null){
        viewHolder=new ViewHolder();
        view=layoutInflater.inflate(R.layout.chat_list_view_item, parent, false);
        viewHolder.listView=view.findViewById(R.id.Chats);
        viewHolder.Kontaktname=view.findViewById(R.id.kontakt_item_name_chat);
        viewHolder.Chatsnippet=view.findViewById(R.id.kontakt_item_chatsnippet);
        viewHolder.Uhrzeit=view.findViewById(R.id.kontakt_item_uhrzeit);
        view.setTag(viewHolder);
    }
    else{
        viewHolder=(ViewHolder)view.getTag();
    }
    Kontakt kontaktItem=listItems.get(position);
    if(kontakt!=null){
        viewHolder.kontakt.setKontakt(kontaktItem);
    }
    else{
        //viewHolder.kontakt=kontaktItem.getKontakt();

    }

    String last_massage=tinyDB.getString(kontaktItem.getNummer()+"text");
    String last_massage_time=tinyDB.getString(kontaktItem.getNummer()+"time");
    String[] Uhrzeit=last_massage_time.split(" ");
    String[] Datum=Uhrzeit[0].split("-");
    String[] Stunden=Uhrzeit[1].split(":");

    Integer Jahr=Integer.parseInt(Datum[0]);
    Integer Monat=Integer.parseInt(Datum[1]);
    Integer Tag=Integer.parseInt(Datum[2]);

    if(Jahr<Kalenderjahr||Monat<Kalendermonat||Tag+1<Kalendertag){
        viewHolder.Uhrzeit.setText(Tag+"."+Monat+"."+Jahr%1000);
    }
    else if(Tag<Kalendertag){
        viewHolder.Uhrzeit.setText(R.string.gestern);
    }
    else{
        viewHolder.Uhrzeit.setText(Stunden[0]+":"+Stunden[1]);
    }

    viewHolder.Kontaktname.setText(kontaktItem.getName());
    viewHolder.Chatsnippet.setText(last_massage);
    //set Image from server

    return view;
}
}

我的onClickListeners ：（也尝试过parent.getChildAt（position）.setBackgroundColor（getResources（）。getColor（R.color.orange））;）

 Chats=findViewById(R.id.Chats);
    final CustomAdapterMain customadapter=new                                           CustomAdapterMain(YouniChat_MainActivity.this,ArrayListChats);
    Chats.setAdapter(customadapter);
 Chats.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
        @Override
        public boolean onItemLongClick(AdapterView parent, View view, int position, long id) {
            hasClicked.put(position,false);
            view.setBackgroundColor(getResources().getColor(R.color.orange));
            marked++;
            Chats.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                @Override
                public void onItemClick(AdapterView parent, View view, int position, long id) {
                    if(hasClicked.get(position,true)) {
                        view.setBackgroundColor(getResources().getColor(R.color.orange));
                        marked++;
                        hasClicked.put(position, false);
                    }
                    else{
                        view.setBackgroundColor(0);
                        marked--;
                        hasClicked.put(position, true);
                    }
                    if(marked>0){
                        findViewById(R.id.delete).setVisibility(View.VISIBLE);
                    }
                    else{
                        findViewById(R.id.delete).setVisibility(View.INVISIBLE);
                        onClickListener();
                    }
                }
            });
            if(marked>0) {
                findViewById(R.id.delete).setVisibility(View.VISIBLE);
            }
            else{
                findViewById(R.id.delete).setVisibility(View.INVISIBLE);
                onClickListener();
            }
            return true; //damit nicht der OnItemClickListener reagiert
        }
    });

滚动时在Listview中获得错误的位置

0 个答案: