滚动时的 BaseAdapter 列表视图位置
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【中文标题】滚动时的 BaseAdapter 列表视图位置【英文标题】：BaseAdapter listview postion while scrolling 【发布时间】：2020-10-29 16:24:00 【问题描述】：我有一个ListView，里面有很多东西。每个项目都有一个按钮，当我单击它时，它变得不可见，而另一个按钮变得可见。
问题是：当我滚动 ListView 时，许多其他项目按钮是不可见的。我该如何解决？
public class homebuyer_fruits_adapter extends BaseAdapter
private ArrayList<Itemssetget> listData;
private LayoutInflater layoutInflater;
public static int cout=0;
List position_item=new ArrayList();
Context context;
String check;
int lastpostition=-1;
public static List<cartitemslist> cartlist=new ArrayList<>();
public homebuyer_fruits_adapter(Context aContext, ArrayList<Itemssetget> listData,String number)
this.listData = listData;
layoutInflater = LayoutInflater.from(aContext);
context=aContext;
check=number;
this.notifyDataSetChanged();
public int getCount()
return listData.size();
@Override
public Object getItem(int position)
return listData.get(position);
@Override
public long getItemId(int position)
return position;
@Override
public View getView(final int position, View v, ViewGroup parent)
final ViewHolder holder;
final cartitemslist homeitemslist = new cartitemslist();
if (v == null)
v = layoutInflater.inflate(R.layout.food_vegitablews_view, null);
holder = new ViewHolder();
holder.name = (TextView) v.findViewById(R.id.name_item);
holder.price = (TextView) v.findViewById(R.id.price_item);
holder.add_q = (ImageView) v.findViewById(R.id.add_quantity);
holder.delete_q = (ImageView) v.findViewById(R.id.delete_quantity);
holder.quantity = (TextView) v.findViewById(R.id.add_quantity_items);
//holder.description = (TextView) v.findViewById(R.id.description_item);
//holder.id = (TextView) v.findViewById(R.id.);
holder.imageView = (ImageView) v.findViewById(R.id.image_items);
holder.discount = (TextView) v.findViewById(R.id.discout_price);
holder.add = (Button) v.findViewById(R.id.addto_cart);
holder.units=(TextView)v.findViewById(R.id.item_units);
holder.percentage=(TextView)v.findViewById(R.id.discount_percentage);
holder.linearLayou=(LinearLayout)v.findViewById(R.id.Quantity_control_linnear_view) ;
holder.phone=check;
v.setTag(holder);
else
holder = (ViewHolder) v.getTag();
this.notifyDataSetChanged();
int i=Integer.parseInt(listData.get(position).getPrice())-Integer.parseInt(listData.get(position).getDiscountprice());
int d=i*100;
if((d/Integer.parseInt(listData.get(position).getPrice()))==0)
holder.percentage.setVisibility(View.GONE);
holder.percentage.setText(""+d/Integer.parseInt(listData.get(position).getPrice())+"% OFF");
holder.name.setText(listData.get(position).getName());
holder.price.setText("Rs " + listData.get(position).getPrice());
if(listData.get(position).getPrice().equals(listData.get(position).getDiscountprice()))
holder.price.setVisibility(View.GONE);
holder.price.setPaintFlags(holder.price.getPaintFlags() | Paint.STRIKE_THRU_TEXT_FLAG);
holder.discount.setText("Rs " + listData.get(position).getDiscountprice());
Picasso.with(context).load(listData.get(position).getImageurl())
.fit().centerCrop().into(holder.imageView);
holder.units.setText(listData.get(position).getUnits());
holder.add_q.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View view)
//Toast.makeText(context,listData.get(position).getName(),Toast.LENGTH_LONG).show();
if(H.containsKey(position))
holder.quantity.setText(""+(1+Integer.parseInt(holder.quantity.getText().toString())));
cartlist.get(H.get(position)).setQuantity(holder.quantity.getText().toString());
);
holder.delete_q.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View view)
if(H.containsKey(position))
if(holder.quantity.getText().toString().equals("1"))
holder.add.setVisibility(View.VISIBLE);
holder.linearLayou.setVisibility(View.GONE);
int i=H.get(position);
cartlist.remove(i);
cout--;
Fruits.numberofitems.setText(cout + "");
else
holder.quantity.setText("" + (Integer.parseInt(holder.quantity.getText().toString()) - 1));
cartlist.get(H.get(position)).setQuantity(holder.quantity.getText().toString());
);
holder.add.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View view)
//Toast.makeText(context,"Add to cart"+holder.name.getText(),Toast.LENGTH_SHORT).show();
holder.add.setVisibility(View.GONE);
holder.linearLayou.setVisibility(View.VISIBLE);
// check=listData.get(position).getPhonenumber_seller();
if(cartlist.isEmpty())
cout++;
homeitemslist.setName(holder.name.getText().toString());
homeitemslist.setPrice(holder.price.getText().toString());
homeitemslist.setDiscountp(holder.discount.getText().toString());
homeitemslist.setQuantity(holder.quantity.getText().toString());
homeitemslist.setPhone_id(holder.phone);
homeitemslist.setImage(listData.get(position).getImageurl());
if(Fruits.numberofitems!=null)
Fruits.numberofitems.setText(cout + "");
shop_items.numberofitems.setText(cout + "");
buyer_home.numberofitems.setText(cout + "");
cartlist.add(homeitemslist);
H.put(position,cartlist.indexOf(homeitemslist));
else
if(check.equals(cartlist.get(0).getPhone_id()))
cout++;
cartitemslist homeitemslist = new cartitemslist();
homeitemslist.setName(holder.name.getText().toString());
homeitemslist.setPrice(holder.price.getText().toString());
homeitemslist.setDiscountp(holder.discount.getText().toString());
homeitemslist.setQuantity(holder.quantity.getText().toString());
homeitemslist.setPhone_id(holder.phone);
homeitemslist.setImage(listData.get(position).getImageurl());
if(Fruits.numberofitems!=null)
Fruits.numberofitems.setText(cout + "");
shop_items.numberofitems.setText(cout + "");
buyer_home.numberofitems.setText(cout + "");
cartlist.add(homeitemslist);
H.put(position,cartlist.indexOf(homeitemslist));
else
Toast.makeText(context,"Clear the Previous cart First than you can buy from this shop",Toast.LENGTH_LONG).show();
);
// holder.description.setText(listData.get(position).getDiscription());
// holder.id.setText(listData.get(position).getId());
//holder.imageView.setImageAlpha(R.drawable.banana);
setanimation(v,position);
return v;
static class ViewHolder
LinearLayout linearLayou;
TextView name;
TextView price;
TextView discount;
ImageView add_q;
ImageView delete_q;
TextView quantity;
ImageView imageView;
TextView description;
TextView units;
TextView percentage;
String phone;
Button add;
public void setanimation(View viewanim,int position)
if(position>lastpostition)
ScaleAnimation animation=new ScaleAnimation(0.0f,1.0f,0.0f,1.0f,
Animation.RELATIVE_TO_SELF,0.5f,Animation.RELATIVE_TO_SELF,0.5f);
animation.setDuration(1500);
viewanim.setAnimation(animation);
lastpostition=position;
这是我的适配器代码。 我尝试了很多方法，但仍然停留在这个问题上。
【问题讨论】：
不能直接在onClick里面使用holder.view，使用setTag()来标记位置等信息。检查我的答案***.com/questions/31169131/… 那我该怎么办？指导我 ViewHolder h=listData.get(position)view.getTag();错误 【参考方案1】：您只在OnClickListener 中设置了可见性，但您也需要在getView() 中设置它，因为滚动时您的视图将被回收（重新用于不同的项目）。
所以在getView() 中，您必须恢复视图的完成 状态，包括按钮可见性。将所有状态信息存储在列表项中。在你的 getView() 里面做这样的事情：
@Override
public View getView(final int position, View v, ViewGroup parent)
...
// the view (v) could be recycled and showing a state from another item
// e.g. the add button is visible
final Itemssetget listItem = listData.get(position);
// so we have to restore the state of the view for listItem above
// e.g. update the button visibility
holder.add.setVisibility(listItem.isAddButtonVisible() ? View.VISIBLE : View.GONE);
holder.add.setOnClickListener(new View.OnClickListener()
@Override
public void onClick(View view)
...
holder.add.setVisibility(View.GONE);
// save the state of the button, so it can be restored later
listItem.setAddButtonVisible(true);
...
...
在Itemssetget中添加必要的成员变量和getter/setter函数：
public class Itemssetget
...
private boolean isAddButtonVisible = false;
public boolean isAddButtonVisible()
return isAddButtonVisible;
public void setAddButtonVisible(boolean isVisible)
this.isAddButtonVisible = isVisible;
...
PS：您的代码看起来很糟糕。看看naming conventions。
【讨论】：
我没有得到它，如果你有任何链接，请解释它，然后分享我 这个答案提供了 ListView 如何工作的基本解释：***.com/a/14108676/4706541 我更新了代码示例以更好地解释解决方案 在这个 listItem.isAddButtonVisible() 中显示错误 您必须在Itemssetget 中创建getter 和setter 函数，它们还不存在。您还需要一个成员变量isAddButtonVisible 来保存状态。我没有包含该代码，因为它应该是不言自明的以上是关于滚动时的 BaseAdapter 列表视图位置的主要内容，如果未能解决你的问题，请参考以下文章
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