Java 更改微调器项数据时更新recyclerview单行数据
我有一个Java 更改微调器项数据时更新recyclerview单行数据,java,android,android-recyclerview,onitemselectedlistener,Java,Android,Android Recyclerview,Onitemselectedlistener,我有一个回收视图,如下图所示 我从服务器获取食物项目数据,并将其绑定到如上所述的RecyclerView 食物项在foodItemList数组列表中分配,该列表具有foodItemType列表数组。在foodItemTypeList数组列表中,存储类型的值及其对应的价格 我想要的是,当用户选择一种食物类型(例如中餐)时,相应的单价会更新 以下是FoodItemAdapter类: public class FoodItemAdapter extends RecyclerView.Adapter&
回收视图
,如下图所示
我从服务器获取食物项目数据,并将其绑定到如上所述的RecyclerView
食物项在foodItemList
数组列表中分配,该列表具有foodItemType列表
数组。在foodItemTypeList
数组列表中,存储类型的值及其对应的价格
我想要的是,当用户选择一种食物类型(例如中餐)时,相应的单价会更新
以下是FoodItemAdapter
类:
public class FoodItemAdapter extends RecyclerView.Adapter<FoodItemAdapter.CustomViewHolder> {
private List<FoodItem> foodItemList;
Context context;
String token;
public class CustomViewHolder extends RecyclerView.ViewHolder {
public TextView food_name, food_unit_price;
Spinner food_item_type;
public ImageView food_item_image;
public Button viewDetail;
public CustomViewHolder(View view) {
super(view);
food_name = (TextView) itemView.findViewById(R.id.food_name);
food_item_type = (Spinner) itemView.findViewById(R.id.food_item_type);
viewDetail = (Button) itemView.findViewById(R.id.viewDetail);
food_unit_price = (TextView) itemView.findViewById(R.id.food_unit_price);
food_item_image = (ImageView) itemView.findViewById(R.id.food_item_image);
}
}
public FoodItemAdapter(Context context, List<FoodItem> foodItemList,String token) {
this.foodItemList = foodItemList;
this.context = context;
this.token = token;
}
@Override
public CustomViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.food_items_item, parent, false);
return new CustomViewHolder(itemView);
}
@Override
public void onBindViewHolder(final CustomViewHolder holder, int position) {
FoodItem foodItem = foodItemList.get(position);
holder.food_name.setText(foodItem.getFood_name());
holder.viewDetail.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
}
});
holder.food_unit_price.setText(foodItem.getFood_unit_price()+" AF");
if(foodItem.getFood_item_image()!=null && !foodItem.getFood_item_image().isEmpty()){
Picasso.get()
.load(foodItem.getFood_item_image())
// To fit image into imageView
.resize(50, 50)
.centerCrop()
.into(holder.food_item_image);
} else {
Log.d("Food Item Image:", "Food Item image is either empty or null");
}
List<FoodItemType> foodItemTypeList = new ArrayList<>();
foodItemTypeList = foodItem.getFoodItemTypeList();
ArrayAdapter userAdapter = new ArrayAdapter(context, R.layout.spinner, foodItemTypeList);
holder.food_item_type.setAdapter(userAdapter);
holder.food_item_type.setOnItemSelectedListener(new
AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int
position, long id) {
FoodItemType foodItemType = (FoodItemType) (holder.food_item_type).getSelectedItem();
Toast.makeText(context, "Clicked: " +
foodItemType.getFood_unit_price(), Toast.LENGTH_LONG).show();
FoodItem foodItemNew = new FoodItem(foodItemList.get(holder.getAdapterPosition()).getFood_item_id(),foodItemList.get(holder.getAdapterPosition()).getFood_category_id(),foodItemList.get(holder.getAdapterPosition()).getFood_name(),foodItemList.get(holder.getAdapterPosition()).getFood_item_image(),foodItemList.get(holder.getAdapterPosition()).getFood_item_desc(), foodItemType.getFood_item_type_id(),foodItemType.getFood_item_type_name(),foodItemType.getFood_unit_price(), foodItemList.get(holder.getAdapterPosition()).getFoodItemTypeList());
foodItemList.set(holder.getAdapterPosition(),foodItemNew);
notifyItemChanged(holder.getAdapterPosition());
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
// todo for nothing selected
}
});
}
@Override
public int getItemCount() {
return foodItemList.size();
}
}
我的问题是:当我滚动RecyclerView
时,视图会被加载多次(有点滞后),而当我更改foody类型(例如:到medium)时,什么都不会发生
非常感谢您的帮助。我建议您在
FoodItem
类中有另一个字段,即selectedFoodType
。这将保存所选类型的索引。默认情况下,使用0初始化该值,当从下拉列表中选择某个项目时,只需相应地更新相应的FoodItem
的selectedFoodType
另一件事是,您不必每次更改FoodItem
的类型时都创建一个新的FoodItem
。您只需要选择foodType
,然后调用notifyDataSetChanged()
因此,代码应该如下所示。在所选的函数中,执行以下操作
int foodType = foodItemTypeList.get(position);
FoodItem foodItem = foodItemNew.get(holder.getAdapterPosition());
foodItem.setSelectedFoodType = foodType;
notifyDataSetChanged();
请注意,我还没有测试这段代码。请根据您的需要进行修改。希望有帮助 这是更改食物时单击toast显示的吗?toast.makeText(上下文,单击:“+foodItemType.getFood\u unit\u price(),toast.LENGTH\u LONG).show()代码>仅用于调试目的。加载recyclerview
时,type small的价格值会多次显示。我认为问题在于onBindViewHolder
。它在滚动期间多次调用,导致延迟。我不知道在onBindViewHolder
Method中实现setOnItemSelectedListener
是否正确。图像大小如何?是否尝试加载没有图像的相同列表?我尝试了您的答案。我注意到,创造新的食物是滞后造成的。使用notifyDataSetChanged()
时,微调器下拉列表冻结。因此,我改为notifyItemChanged(holder.getAdapterPosition())代码>这一次,当我选择一种食物类型(例如中号)时,它会刷新回小号。您还需要在微调器中设置所选项目。使用selectedFoodType
作为您的onBindViewHolder
中的微调器选定项。
int foodType = foodItemTypeList.get(position);
FoodItem foodItem = foodItemNew.get(holder.getAdapterPosition());
foodItem.setSelectedFoodType = foodType;
notifyDataSetChanged();