我有一个RecyclerView，滚动后，我adapter中的项目值会进行交换。这显然是回收视图的问题，基础数据未被清除。
但是，我已经阅读了这个问题的几十次迭代，但我无法从任何答案中解读明确的解决方案，而且我的问题仍然存在。
我将Adapter设置为具有稳定ID，覆盖getItem，getItemId和getItemCount方法，并且 - 我认为 - 对我执行正确的检查onBindViewHolder方法来判断我的数据是否干净......但最后一部分让我感到困惑，因为我不确定我应该执行什么条件（我感觉大部分的答案）缺乏这些问题）......
以下是一些相关代码：
public class MenuQueryAdapter extends ParseRecyclerQueryAdapter<MenuItem, MenuQueryAdapter.MenuViewHolder> {
public MenuQueryAdapter(ParseQueryAdapter.QueryFactory<MenuItem> factory, boolean hasStableIds) {
super(factory, hasStableIds);// hasStableIds set to TRUE
}
@Override
public MenuViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new MenuViewHolder(LayoutInflater.from(parent.getContext()).inflate(R.layout.menu_item, parent, false));
}
@Override
public void onBindViewHolder(MenuViewHolder holder, int position) {
MenuItem menuItem = getItem(position);
holder.bindItem(menuItem);
}
@Override
public MenuItem getItem(int position) {
//return super.getItem(position);
if (menuItemList != null && menuItemList.size() > 0) {
return menuItemList.get(position);
}
return super.getItem(position);
}
@Override
public long getItemId(int position) {
return position;
}
// View Holder
public static class MenuViewHolder extends RecyclerView.ViewHolder {
MenuItem menuItem;
TextView title;
TextView price;
TextView summary;
TextView itemCount;
TextView calorieLabel;
TextView proteinLabel;
TextView fatLabel;
TextView carbsLabel;
TextView fiberLabel;
ParseImageView imageView;
private String objectId = "";
private boolean active = true;
private boolean inStock = true;
private boolean cSoon = false;
private boolean hasNutrition = false;
MenuViewHolder(View itemView) {
super(itemView);
title = (TextView) itemView.findViewById(R.id.menu_title_label);
price = (TextView) itemView.findViewById(R.id.menu_price_label);
summary = (TextView) itemView.findViewById(R.id.menu_summary);
calorieLabel = (TextView) itemView.findViewById(R.id.menu_label_calorie_value);
proteinLabel = (TextView) itemView.findViewById(R.id.menu_label_protein_value);
fatLabel = (TextView) itemView.findViewById(R.id.menu_label_fat_value);
carbsLabel = (TextView) itemView.findViewById(R.id.menu_label_carbs_value);
fiberLabel = (TextView) itemView.findViewById(R.id.menu_label_fibre_value);
imageView = (ParseImageView) itemView.findViewById(R.id.menu_main_image);
// Containers
final RelativeLayout activeView = (RelativeLayout) itemView.findViewById(R.id.menu_top_view_active);
final RelativeLayout inactiveView = (RelativeLayout) itemView.findViewById(R.id.menu_top_view_inactive);
View.OnClickListener clickListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
active = !active;
if(active)
{
activeView.setVisibility(View.VISIBLE);
inactiveView.setVisibility(View.INVISIBLE);
}
else
{
activeView.setVisibility(View.INVISIBLE);
inactiveView.setVisibility(View.VISIBLE);
}
}
};
final RelativeLayout topView = (RelativeLayout) itemView.findViewById(R.id.menu_top_view);
topView.setOnClickListener(clickListener);
final ImageButton info = (ImageButton) itemView.findViewById(R.id.menu_info_button);
info.setOnClickListener(clickListener);
}
public void bindItem(MenuItem item) {
menuItem = item;
menuItem.populateData(); // gets data from DB
// THIS IS MY CHECK TO SEE IF THE DATA SHOULD EB RECYCLED
if( !menuItem.getTitle().equals(enroot.getContext().getResources().getString(R.string.menu_title)) ) {
title.setText(menuItem.getTitle());
price.setText(String.valueOf(menuItem.getPrice()));
summary.setText(menuItem.getSummary());
calorieLabel.setText(menuItem.getCalories());
proteinLabel.setText(menuItem.getProtein());
fatLabel.setText(menuItem.getFat());
carbsLabel.setText(menuItem.getCarbs());
fiberLabel.setText(menuItem.getFibre());
imageView.setParseFile(menuItem.getImage());
imageView.loadInBackground();
if (menuItem.getInt(EnrootConstants.kERItemInStockKey) <= 0) {
inStock = false;
}
if (menuItem.getBoolean(EnrootConstants.kERItemComingSoonKey) && inStock) {
cSoon = true;
}
if (menuItem.getList(EnrootConstants.kERItemNutritionKey) != null && menuItem.getList(EnrootConstants.kERItemNutritionKey).size() > 0) {
hasNutrition = true;
}
// Id
objectId = menuItem.getObjectId();
if (mOnItemChangedListener != null) {
mOnItemChangedListener.passIdToActivity(objectId);
}
// Stock
RelativeLayout ooStock = (RelativeLayout) itemView.findViewById(R.id.menu_soldout);
if (!inStock) {
ooStock.setVisibility(View.VISIBLE);
}
// Coming Soon
RelativeLayout comingSoon = (RelativeLayout) itemView.findViewById(R.id.menu_comingsoon);
if (cSoon) {
comingSoon.setVisibility(View.VISIBLE);
}
// Nutrition
if (!hasNutrition) {
RelativeLayout nutritionOverlay = (RelativeLayout) itemView.findViewById(R.id.menu_nutrition_group);
nutritionOverlay.setVisibility(View.INVISIBLE);
}
// Minus
final ImageButton minus = (ImageButton) itemView.findViewById(R.id.menu_btn_minus);
if (inStock && !cSoon) {
minus.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mOnItemChangedListener != null) {
mOnItemChangedListener.onPriceSubtracted(objectId, getAdapterPosition());
}
}
});
} else {
minus.setVisibility(View.INVISIBLE);
minus.setEnabled(false);
minus.setClickable(false);
}
// Plus
final ImageButton plus = (ImageButton) itemView.findViewById(R.id.menu_btn_plus);
if (inStock && !cSoon) {
plus.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mOnItemChangedListener != null) {
mOnItemChangedListener.onPriceAdded(objectId, getAdapterPosition());
}
}
});
} else {
plus.setVisibility(View.INVISIBLE);
plus.setEnabled(false);
plus.setClickable(false);
}
}
else {
clearItem();
}
}
void clearItem() {
title.setText("");
price.setText("");
summary.setText("");
calorieLabel.setText("");
proteinLabel.setText("");
fatLabel.setText("");
carbsLabel.setText("");
fiberLabel.setText("");
objectId = "";
active = true;
inStock = true;
cSoon = false;
hasNutrition = false;
}
} /* eoc holder */
} /* eoc adapter */
所以...我看到很多关于简单地覆盖getItem和/或getItemId的讨论（如果你有稳定的ID，这是有道理的），但似乎没有影响。我甚至在setIsRecyclable上将ViewHolder设置为false，没有效果。
我被困了......如果我做了一件可怕的错误，我很乐意听到......
答案 0 :(得分：0)
我认为您错过了返回项目计数
@Override
public int getItemCount() {
return menuItemList.size();
}