ExpandableListView：从孩子那里获取输入值

Posted 2023-05-07

【中文标题】ExpandableListView：从孩子那里获取输入值

【英文标题】：ExpandableListView: Get input values from childs

【发布时间】：2019-09-26 05:16:06

【问题描述】：

我正在将 JSON 解析为 ExpandableListView，在每个孩子上，用户可以选择他想要的每个孩子的数量 +/- 按钮。 +/- 按钮连接到 TextView，其中显示每个孩子的总金额，总费用将显示在行尾。

在父级的底部应该有一个TextView，其中包含在ExpListView的每个子级中计算的所有值的摘要（摘要） 底部的 OK 按钮应该将每个孩子的金额发送到服务器（金额连接到一个 ID）。

当我点击“确定”按钮时，我在读取每个孩子的数量时遇到问题 - 我如何搭建通往孩子价值观的桥梁？

我也遇到了读取每个孩子的成本以计算底部的总成本的问题。 Child 中的 onClickListener 应该以某种方式刷新底部的 TextView，但据我所知，这并不容易，对吧？

有人知道如何访问这些值吗？

这是我的 ListAdapter 的 ChildView 发生魔法的地方：

public class ExpandableListAdapterDrinks extends BaseExpandableListAdapter 
private Context context;
private List<String> listDataHeader,listDataHeaderPrice;
private HashMap<String,List<String>> listHashMap;
private List<Drink> drinksList;


class ViewHolder 
    TextView childText,counterText, childUnitPrice, childFinalPrice;
    Button btn_plus,btn_minus;



class DrinksListChildItem
    String name;
    int quantity;
    DrinksListChildItem(String name, int quantity)
        this.name = name;
        this.quantity = quantity;
    


class Pos
    int group;
    int child;
    Pos(int group, int child)
        this.group = group;
        this.child = child;
    





public ExpandableListAdapterDrinks(Context context, List<Drink> drinksList) 
    this.context = context;
    this.drinksList= drinksList;

  




@Override
public int getGroupCount() 
    return drinksList.size();



@Override
public int getChildrenCount(int groupPosition) 

    return drinksList.get(groupPosition).getContent().size();



@Override
public Object getGroup(int groupPosition) 
    return drinksList.get(groupPosition);



@Override
public Object getChild(int groupPosition, int childPosition) 
    return drinksList.get(groupPosition).getContent();
     listHashMap.get(listDataHeader.get(groupPosition)).get(childPosition);


@Override
public long getGroupId(int groupPosition) 
    return groupPosition;


@Override
public long getChildId(int groupPosition, int childPosition) 
    return childPosition;


@Override
public boolean hasStableIds() 
    return false;




@Override
public View getGroupView(final int groupPosition, boolean isExpanded, View view, ViewGroup parent) 
    String headerTitle = (String) drinksList.get(groupPosition).getTitle();

    /** HEADER TEXT HERE */



    if(view==null) 
        LayoutInflater inflater = (LayoutInflater)this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.vip_package_listgroup,null);
    
    final LinearLayout bgcolor = view.findViewById(R.id.lblListHeaderLayout);
    TextView lblListHeader = (TextView)view.findViewById(R.id.lblListHeader);
    TextView lblListHeaderPrice = (TextView)view.findViewById(R.id.lblListHeader_Price);
    Button lblListHeaderButton = view.findViewById(R.id.lblListHeaderButton);

    lblListHeaderPrice.setVisibility(View.GONE);
    lblListHeaderButton.setVisibility(View.GONE);

    if(!drinksList.get(groupPosition).getBg().get(0).isEmpty() || !drinksList.get(groupPosition).getBg().get(1).isEmpty() ) 

        List<String> colorGradientTopBottom = drinksList.get(groupPosition).getBg();

        int[] colors = Color.parseColor(colorGradientTopBottom.get(0)),Color.parseColor(colorGradientTopBottom.get(1));
        GradientDrawable gd = new GradientDrawable(GradientDrawable.Orientation.TOP_BOTTOM, colors);
        gd.setCornerRadius(0f);
        bgcolor.setBackground(gd);
     else 

        bgcolor.setBackgroundColor(ContextCompat.getColor(context, R.color.cardview_bg));
    

    lblListHeader.setText(headerTitle);

    return view;



@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View view, ViewGroup parent) 

    /** Drinks List */
    final ViewHolder viewHolder;

    final List<String> childDrink = drinksList.get(groupPosition).getContent();
    final List<Integer> childPrice = drinksList.get(groupPosition).getPricelist();
    //final String childText =  childDrink.get(childPosition);

    if(view == null) 
        LayoutInflater inflater = (LayoutInflater)this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.vip_drinks_listitem,null);

        final TextView txtListChild = view.findViewById(R.id.lblListItemDrinks);
        final TextView txtListDrinksUnitPrice = view.findViewById(R.id.lblListItemDrinksUnitPrice);
        final TextView txtDrinksAmount = view.findViewById(R.id.vip_drinks_amount);
        final TextView txtListDrinkPriceFinal = view.findViewById(R.id.lblListItemDrinksFinalPrice);
        Button btn_plus = view.findViewById(R.id.vip_drinks_btn_plus);
        Button btn_minus = view.findViewById(R.id.vip_drinks_btn_minus);

        viewHolder = new ViewHolder();
        viewHolder.childText = txtListChild;
        viewHolder.childUnitPrice = txtListDrinksUnitPrice;
        viewHolder.counterText = txtDrinksAmount;
        viewHolder.childFinalPrice = txtListDrinkPriceFinal;
        viewHolder.btn_plus = btn_plus;
        viewHolder.btn_minus = btn_minus;


        viewHolder.childText.setText(childDrink.get(childPosition));
        viewHolder.counterText.setText("0");
        viewHolder.childFinalPrice.setText("0");
        final float headerPrice = childPrice.get(childPosition);
        final int headerPriceInt = (int) headerPrice;
        viewHolder.childUnitPrice.setText(String.format("%.02f",headerPrice).replace(".",",") +"€");

        DrinksListChildItem child = childDrink.get(childPosition);


        viewHolder.btn_plus.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 

                int t = Integer.parseInt(viewHolder.counterText.getText().toString());
                ChildItem selectedItem = viewHolder.counterText.getText().toString();
                selectedItem.quantity = selectedItem.quantity+1;
                notifyDataSetChanged();

                viewHolder.counterText.setText(String.valueOf(t + 1));
                viewHolder.childFinalPrice.setText(String.valueOf((t+1)* headerPriceInt) + "€");
            
        );



        viewHolder.btn_minus.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                Pos pos = (Pos) v.getTag();
                int t = Integer.parseInt(viewHolder.counterText.getText().toString());
                DrinksListChildItem selectedItem = (DrinksListChildItem) getChild(pos.group,pos.child);
                selectedItem.quantity = selectedItem.quantity-1;
                notifyDataSetChanged();
                viewHolder.counterText.setText(String.valueOf(t - 1));
                viewHolder.counterText.setText(String.valueOf((t-1)* headerPriceInt) + "€");
            
        );


     else 
        viewHolder = (ViewHolder) view.getTag();
    


    return view;

我在将您的代码粘贴到我的代码时遇到了很多问题（使用 TextView 扩展问题）：我不明白如何连接 ChildItem child = childDrink.get(childPosition);到我的drinksList 以使setOnCLickListener 增加selectedItem.quantity。该代码以某种方式起作用，但它弄乱了我孩子的顺序，它还选择了其他孩子的数量

饮料（Pojo）

public class Drink 
@SerializedName("title")
@Expose
private String title;
@SerializedName("bg")
@Expose
private List<String> bg = null;
@SerializedName("content")
@Expose
private List<String> content = null;
@SerializedName("pricelist")
@Expose
private List<Integer> pricelist = null;

public String getTitle() 
    return title;


public void setTitle(String title) 
    this.title = title;


public List<String> getBg() 
    return bg;


public void setBg(List<String> bg) 
    this.bg = bg;


public List<String> getContent() 
    return content;


public void setContent(List<String> content) 
    this.content = content;


public List<Integer> getPricelist() 
    return pricelist;


public void setPricelist(List<Integer> pricelist) 
    this.pricelist = pricelist;

VipDrinks(Pojo): 公共类 VipDrinks

@SerializedName("drinks")
@Expose
private List<Drink> drinks = null;

public List<Drink> getDrinks() 
    return drinks;


public void setDrinks(List<Drink> drinks) 
    this.drinks = drinks;

JSON 的结构如下：

 "drinks":[ 
              "title":,
              "bg":[],
              "content":[],
              "pricelist":[],
             ,
            ... 
          ]
 

这是带有解析请求的活动：

public class drinks_selection extends AppCompatActivity 


    @Override
    protected void onCreate(Bundle savedInstanceState) 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_drinks_selection);

        final ExpandableListView listView = findViewById(R.id.vip_drinks_listview);


        /** PARSING JSON FROM SERVER */

        final JsonObjectRequest galleryUrls = new JsonObjectRequest(Request.Method.GET, PARSE_URL, null, new Response.Listener<JSONObject>() 
            @Override
            public void onResponse(JSONObject response) 
                try 
                    JSONArray packageArray = response.getJSONArray("drinks");
                    Log.e("response", String.valueOf(response));
                    GsonBuilder gsonBuilder = new GsonBuilder();
                    Gson gson = gsonBuilder.create();
                    List<Drink> vipDrinks = Arrays.asList(gson.fromJson(String.valueOf(packageArray),Drink[].class));
                    List<Drink> arrayList = new ArrayList<>(vipDrinks);

                    ExpandableListAdapterDrinks listAdapter = new ExpandableListAdapterDrinks(getApplicationContext(),arrayList);
                    listView.setAdapter( listAdapter);
                    listView.expandGroup(0);

                 catch (JSONException e) 
                    e.printStackTrace();
                

            
        , new Response.ErrorListener() 
            @Override
            public void onErrorResponse(VolleyError error) 


                Log.e("ERROR", String.valueOf(error));
            
        );

        RequestQueue rQ = Volley.newRequestQueue(this);
        rQ.add(galleryUrls);

    

VIP包列表Group.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:id="@+id/lblListHeaderLayout"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_
    android:layout_
    android:padding="@dimen/default_padding"
    android:background="@drawable/bg_vip_booking"
    android:orientation="horizontal"

    >

<RelativeLayout

    android:layout_
    android:layout_
    android:paddingStart="?android:attr/expandableListPreferredItemPaddingLeft"
    android:paddingEnd="@dimen/feed_item_padding_left_right"
    android:layout_weight="0.9"
    >

    <TextView
        android:id="@+id/lblListHeader"
        android:textSize="@dimen/text_title_list_header"
        android:textColor="@color/Textwhite"
        android:layout_
        android:layout_
        android:fontFamily="@font/mont_bold"

        />

    <TextView
        android:id="@+id/lblListHeader_Price"
        android:textSize="@dimen/text_title_list_header"
        android:textColor="@color/Textwhite"
        android:layout_
        android:layout_
        android:layout_alignParentEnd="true"
        android:fontFamily="@font/mont_bold"

        />
</RelativeLayout>

    <Button
        android:id="@+id/lblListHeaderButton"
        android:layout_
        android:layout_
        android:background="@drawable/bg_btn_ripple_dark"
        android:text="@string/btn_ok"
        android:textColor="@color/Textwhite"
        android:fontFamily="@font/mont_bold"
        android:focusable="false"

        />

</LinearLayout>

VIP 酒水 ListItem.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_
    android:layout_
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_centerInParent="true"

    >


    <TextView
        android:id="@+id/lblListItemDrinks"
        android:paddingTop="@dimen/padding_small"
        android:paddingBottom="@dimen/padding_small"
        android:textSize="@dimen/text_normal"
        android:paddingLeft="@dimen/default_padding"
        android:layout_
        android:layout_
        android:fontFamily="@font/mont_medium"
        android:textColor="@color/Textwhite"
        app:layout_constraintStart_toStartOf="parent"


        />



    <RelativeLayout
        android:id="@+id/vip_drinks_layout"
        android:layout_
        android:layout_
        android:layout_toEndOf="@id/lblListItemDrinks"
        android:paddingStart="@dimen/default_padding"
        android:layout_centerInParent="true"
        android:paddingEnd="@dimen/default_padding"
        app:layout_constraintEnd_toEndOf="parent"



        >

        <TextView
            android:id="@+id/lblListItemDrinksUnitPrice"
            android:textSize="@dimen/text_normal"
            android:layout_
            android:layout_
            android:fontFamily="@font/mont_light"
            android:textColor="@color/Textwhite"
            android:paddingEnd="@dimen/padding_small"
            />

        <Button
            android:id="@+id/vip_drinks_btn_minus"
            android:layout_toEndOf="@id/lblListItemDrinksUnitPrice"

            android:layout_
            android:layout_
            android:text="-"

            android:background="@drawable/bg_btn_ripple_dark"
            android:textColor="@color/white"
            android:textSize="14sp"
            android:layout_marginEnd="@dimen/padding_small"

            />


        <TextView
            android:id="@+id/vip_drinks_amount"
            android:layout_toEndOf="@+id/vip_drinks_btn_minus"


            android:layout_
            android:layout_
            android:textColor="@color/white"
            android:fontFamily="@font/mont_light"
            android:textSize="@dimen/text_normal"
            android:layout_marginEnd="@dimen/padding_small"
            />


        <Button
            android:id="@+id/vip_drinks_btn_plus"
            android:layout_toEndOf="@+id/vip_drinks_amount"

            android:layout_
            android:layout_
            android:text="+"
            android:background="@drawable/bg_btn_ripple_dark"
            android:textColor="@color/white"
            android:textSize="14sp"
            android:layout_marginEnd="@dimen/padding_small"

            />


        <TextView
            android:id="@+id/lblListItemDrinksFinalPrice"
            android:layout_toEndOf="@id/vip_drinks_btn_plus"
            android:textSize="@dimen/text_normal"
            android:layout_
            android:layout_
            android:fontFamily="@font/mont_light"
            android:textColor="@color/Textwhite"

            />
    </RelativeLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

【问题讨论】：

由于 View 会被重复使用/回收，所以将数据保存在 TextView 中是错误的。它们将在折叠/展开或滚动后网格化。尝试修改您的饮料列表以保留数据。我在这篇文章中的示例可能会有所帮助：***.com/questions/50092400/…

对于 OK 按钮，尝试在适配器内部创建一个公共方法并获取那些选择的数量不为 0 的子项。看看 getOrderList() b> 我对这篇文章的回答的适配器中的方法：***.com/questions/50288713/…

要访问 ExpandableListView 之外的 TextView，请尝试：1。在适配器中，添加一个TextView全局变量； 2.在适配器的构造函数中，为TextView添加一个参数； 3. 在构造函数中，使 TextView 全局变量 = TextView 参数。希望有帮助！

查看我的代码更新，由于您在代码中使用的 HashMap 而我的代码中缺少，因此无法将您的 selectedItem.quantity 连接到我的 DrinksList

请同时发布 Drink 课程。

【参考方案1】：

像这样添加一个新类SelectedDrink：

public class SelectedDrink 
String content;
int qty;

然后试试这个适配器代码：

public class ExpandableListAdapterDrinks extends BaseExpandableListAdapter 

private Context context;
private List<Drink> drinksList;

private Button btReset, btOk;
private List<Integer> groupSum;
private List<List<Integer>> qty;
private int totalSum = 0;

class ViewHolder 
    TextView childText,counterText, childUnitPrice, childFinalPrice;
    Button btn_plus,btn_minus;


class Pos
    int group;
    int child;
    Pos(int group, int child)
        this.group = group;
        this.child = child;
    


public ExpandableListAdapterDrinks(Context context, List<Drink> drinksList,
                                   Button btReset, Button btOk) 
    this.context = context;
    this.drinksList= drinksList;
    this.btReset = btReset;
    this.btOk = btOk;

    groupSum = new ArrayList<>();
    qty = new ArrayList<>();
    for(int i=0; i<drinksList.size(); i++) 
        groupSum.add(0);
        List<Integer> orderedQty = new ArrayList<>();
        for(int j=0; j<drinksList.get(i).getContent().size(); j++) orderedQty.add(0);
        qty.add(orderedQty);
    


private void resetGroupSum(int groupPosition) 
    totalSum -= groupSum.get(groupPosition);
    groupSum.set(groupPosition, 0);
    resetGroupChildrenQty(groupPosition);


private void resetGroupChildrenQty(int groupPosition) 
    for(int i=0; i<qty.get(groupPosition).size(); i++) qty.get(groupPosition).set(i, 0);


@Override
public int getGroupCount() 
    return drinksList.size();


@Override
public int getChildrenCount(int groupPosition) 
    return drinksList.get(groupPosition).getContent().size();


@Override
public Drink getGroup(int groupPosition) 
    return drinksList.get(groupPosition);


@Override
public String getChild(int groupPosition, int childPosition) 
    return drinksList.get(groupPosition).getContent().get(childPosition);


@Override
public long getGroupId(int groupPosition) 
    return groupPosition;


@Override
public long getChildId(int groupPosition, int childPosition) 
    return childPosition;


@Override
public boolean hasStableIds() 
    return false;


@Override
public View getGroupView(int groupPosition, boolean isExpanded, View view, ViewGroup parent) 
    String headerTitle = drinksList.get(groupPosition).getTitle();

    /** HEADER TEXT HERE */
    if(view==null) 
        LayoutInflater inflater = (LayoutInflater)this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.vip_package_listgroup,null);
    
    LinearLayout bgcolor = view.findViewById(R.id.lblListHeaderLayout);
    TextView lblListHeader = (TextView)view.findViewById(R.id.lblListHeader);
    TextView lblListHeaderPrice = (TextView)view.findViewById(R.id.lblListHeader_Price);
    Button lblListHeaderButton = view.findViewById(R.id.lblListHeaderButton);

    if(groupSum.get(groupPosition) > 0)
        lblListHeaderPrice.setVisibility(View.VISIBLE);
        lblListHeaderPrice.setText(String.format("%.02f", (float)groupSum.get(groupPosition)).replace(".", ",") + "€");
    else
        lblListHeaderPrice.setVisibility(View.GONE);
        lblListHeaderButton.setVisibility(View.GONE);
    

    if(!drinksList.get(groupPosition).getBg().get(0).isEmpty() || !drinksList.get(groupPosition).getBg().get(1).isEmpty() ) 
        List<String> colorGradientTopBottom = drinksList.get(groupPosition).getBg();
        int[] colors = Color.parseColor(colorGradientTopBottom.get(0)),Color.parseColor(colorGradientTopBottom.get(1));
        GradientDrawable gd = new GradientDrawable(GradientDrawable.Orientation.TOP_BOTTOM, colors);
        gd.setCornerRadius(0f);
        bgcolor.setBackground(gd);
     else 
        //bgcolor.setBackgroundColor(ContextCompat.getColor(context, R.color.cardview_bg));
    
    lblListHeader.setText(headerTitle);

    return view;


@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View view, ViewGroup parent) 

    /** Drinks List */
    ViewHolder viewHolder;

    String childDrink = getChild(groupPosition, childPosition);
    int childPrice = getGroup(groupPosition).getPricelist().get(childPosition);

    if (view == null) 
        LayoutInflater inflater = (LayoutInflater) this.context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view = inflater.inflate(R.layout.vip_drinks_listitem, null);

        viewHolder = new ViewHolder();
        viewHolder.childText = view.findViewById(R.id.lblListItemDrinks);
        viewHolder.childUnitPrice = view.findViewById(R.id.lblListItemDrinksUnitPrice);
        viewHolder.counterText = view.findViewById(R.id.vip_drinks_amount);
        viewHolder.childFinalPrice = view.findViewById(R.id.lblListItemDrinksFinalPrice);
        viewHolder.btn_plus = view.findViewById(R.id.vip_drinks_btn_plus);
        viewHolder.btn_minus = view.findViewById(R.id.vip_drinks_btn_minus);

        viewHolder.btn_plus.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                Pos pos = (Pos) v.getTag();
                int orderedQty = qty.get(pos.group).get(pos.child);
                orderedQty++;
                qty.get((pos.group)).set(pos.child, orderedQty);
                groupSum.set(pos.group, groupSum.get(pos.group) + getGroup(pos.group).getPricelist().get(pos.child));
                notifyDataSetChanged();
                totalSum += getGroup(pos.group).getPricelist().get(pos.child);
                btOk.setText(String.format("%.02f", (float)totalSum).replace(".", ",") + "€");
                btReset.setEnabled(true);
            
        );

        viewHolder.btn_minus.setOnClickListener(new View.OnClickListener() 
            @Override
            public void onClick(View v) 
                Pos pos = (Pos) v.getTag();
                int orderedQty = qty.get(pos.group).get(pos.child);
                if (orderedQty > 0) 
                    orderedQty--;
                    qty.get((pos.group)).set(pos.child, orderedQty);
                    groupSum.set(pos.group, groupSum.get(pos.group) - getGroup(pos.group).getPricelist().get(pos.child));
                    notifyDataSetChanged();
                    totalSum -= getGroup(pos.group).getPricelist().get(pos.child);
                    if (totalSum == 0) resetTotalSum();
                    else btOk.setText(String.format("%.02f", (float)totalSum).replace(".", ",") + "€");
                
            
        );
     else 
        viewHolder = (ViewHolder) view.getTag();
    

    viewHolder.childText.setText(childDrink);
    viewHolder.childUnitPrice.setText(String.format("%.02f", (float)childPrice).replace(".", ",") + "€");
    int orderedQty = qty.get(groupPosition).get(childPosition);
    viewHolder.counterText.setText(String.valueOf(orderedQty));
    viewHolder.childFinalPrice.setText(String.format("%.02f", (float)orderedQty*childPrice).replace(".", ",") + "€");

    viewHolder.btn_minus.setTag(new Pos(groupPosition, childPosition));
    viewHolder.btn_plus.setTag(new Pos(groupPosition, childPosition));
    view.setTag(viewHolder);
    return view;


@Override
public boolean isChildSelectable(int i, int i1) 
    return false;


public void resetTotalSum() 
    for(int i=0; i<drinksList.size(); i++) 
        resetGroupSum(i);
    
    notifyDataSetChanged();
    btReset.setEnabled(false);
    btOk.setText(String.valueOf(0));


public ArrayList<SelectedDrink> getOrderList() 
    ArrayList<SelectedDrink> orderList = new ArrayList<>();
    for(int i=0; i<drinksList.size(); i++) 
        for(int j=0; j<drinksList.get(i).getContent().size(); j++) 
            if(qty.get(i).get(j) > 0) 
                SelectedDrink selectedDrink = new SelectedDrink();
                selectedDrink.content = getGroup(i).getContent().get(j);
                selectedDrink.qty = qty.get(i).get(j);
                orderList.add(selectedDrink);
            
        
    
    return orderList;

我用这个活动测试上述内容：

public class MainActivity extends AppCompatActivity 
final private static int NUM_OF_GROUP = 5;
List<Drink> drinksList;
ExpandableListView listView;
ExpandableListAdapterDrinks expandableListAdapterDrinks;

@Override
protected void onCreate(Bundle savedInstanceState) 
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Button btRest = findViewById(R.id.btReset);
    Button btOk = findViewById(R.id.btOK);
    listView = findViewById(R.id.elvDrinks);

    initDataList();
    expandableListAdapterDrinks =
            new ExpandableListAdapterDrinks(getApplicationContext(), drinksList, btRest, btOk);
    listView.setAdapter(expandableListAdapterDrinks);
    listView.expandGroup(0);

    btRest.setOnClickListener(new View.OnClickListener() 
        @Override
        public void onClick(View view) 
            expandableListAdapterDrinks.resetTotalSum();
            for(int i=0; i<drinksList.size(); i++) listView.collapseGroup(i);
            listView.expandGroup(0);
        
    );
    btOk.setOnClickListener(new View.OnClickListener() 
        @Override
        public void onClick(View view) 
            String msg = "Nothing Selected";
            Button button = (Button)view;
            if(!button.getText().equals("0")) 
                msg = "Upload!\n";
                ArrayList<SelectedDrink> selectedDrinks = expandableListAdapterDrinks.getOrderList();
                for(SelectedDrink selectedDrink: selectedDrinks) 
                    msg += selectedDrink.content + "    " + selectedDrink.qty + "\n";
                
                msg += "Total: " + button.getText();
            
            Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();
        
    );


private void initDataList()
    drinksList = new ArrayList<>();
    List<String> content;
    List<Integer> pricelist;
    List<String> bg;
    for(int i=1; i<=NUM_OF_GROUP; i++) 
        content = new ArrayList<>();
        pricelist = new ArrayList<>();
        bg = new ArrayList<>();
        for(int j = 1; j<(NUM_OF_GROUP + new Random().nextInt(5)); j++)
            content.add("Drink " + i + "-" + j);
            pricelist.add(new Random().nextInt(1000));
            bg.add("#008577");
            bg.add("#D81B60");
        
        Drink drink = new Drink();
        drink.setTitle("Group " + i);
        drink.setContent(content);
        drink.setPricelist(pricelist);
        drink.setBg(bg);
        drinksList.add(drink);
    

还有这个布局：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_
android:layout_
tools:context=".MainActivity">

<LinearLayout
    android:id="@+id/llBtns"
    android:layout_
    android:layout_
    android:layout_alignParentBottom="true"
    android:orientation="horizontal">

    <Button
        android:id="@+id/btReset"
        android:layout_
        android:layout_
        android:layout_weight="1"
        android:enabled="false"
        android:text="Reset" />

    <Button
        android:id="@+id/btOK"
        android:layout_
        android:layout_
        android:layout_weight="0.5"
        android:text="0" />
</LinearLayout>

<ExpandableListView
    android:id="@+id/elvDrinks"
    android:layout_
    android:layout_
    android:layout_above="@id/llBtns">
</ExpandableListView>

</RelativeLayout>

此外，还需要您的 Drink 类、vip_package_listgroup.xml 和 vip_drinks_listitem.xml。希望对您有所帮助！

【讨论】：

我添加了 vip_package_listgroup.xml 和 vip_drinks_listitem.xml + Drink.class 是一个 Pojo 类，你确定你需要 POJO 类而不是别的东西吗？

感谢您的帮助。我应该给你买杯啤酒。我会尽快测试代码并返回结果:)

这非常完美！谢谢