我正在开发购物应用程序。我有一个包含价格和数量的列表视图。所有单元格的价格和数量的乘积应显示在底部的文本视图中。如何做到这一点？
先谢谢了。
适配器类
公共类CustomAdaptercartlist扩展了BaseAdapter {
private List<Model> filteredData = null;
private LayoutInflater mInflater;
private Activity i;
private FirebaseFirestore db = FirebaseFirestore.getInstance();
Float p;
Float totalprice;
public CustomAdaptercartlist(Context context, List<Model> data, Activity i) {
this.filteredData = data ;
mInflater = LayoutInflater.from(context);
this.i=i;
}
@Override
public int getCount() {
int i;
if(filteredData == null) {
i = 0;
}
else {
i = filteredData.size();
}
return i;
}
@Override
public Object getItem(int i) {
return filteredData.get(i);
}
@Override
public long getItemId(int i) {
return i;
}
class ViewHolder {
TextView name;
TextView price;
TextView quantity;
TextView image_path,pq;
ImageView image;
LinearLayout layout;
Button delete;
}
ViewHolder holder;
@SuppressLint({"ViewHolder", "InflateParams", "SetTextI18n", "NewApi"})
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
holder= new ViewHolder();
//===================initializing identitifiers===============//
convertView = mInflater.inflate(R.layout.row_search_iteam_cartlist, null);
holder.name = convertView.findViewById(R.id.name);
holder.price = convertView.findViewById(R.id.price);
holder.quantity = convertView.findViewById(R.id.quantity);
holder.image_path = convertView.findViewById(R.id.ip);
holder.image = convertView.findViewById(R.id.image);
holder.image_path.setClipToOutline(true);
holder.delete = convertView.findViewById(R.id.delete);
holder.pq = convertView.findViewById(R.id.pq);
convertView.setTag(holder);
//======================== setting values for listview cell====================//
holder.name.setText(filteredData.get(position).getName());
holder.price.setText("$"+ filteredData.get(position).getPrice());
int qty = Integer.parseInt(filteredData.get(position).getqty());
Float pri = Float.valueOf(filteredData.get(position).getPrice());
holder.image_path.setText(filteredData.get(position).getImage_path());
holder.quantity.setText(filteredData.get(position).getqty());
totalprice = qty * pri;
holder.pq.setText(qty + "*" + pri + "=" + totalprice);
final String user_id;
FirebaseAuth mAuth = FirebaseAuth.getInstance();
user_id = mAuth.getUid();
holder.delete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
db.collection("UserProfile").document(user_id).collection("Cart")
.document(filteredData.get(position).getProductId()).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
DocumentSnapshot documentSnapshot = task.getResult();
if(documentSnapshot.exists()){
final int q = Integer.parseInt(documentSnapshot.getString("Quantity"));
String sid = documentSnapshot.getString("StoreId");
String pid = documentSnapshot.getString("ProductId");
db.collection("Products").document(pid).collection("Stores").document(sid).
get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
DocumentSnapshot documentSnapshot = task.getResult();
if(documentSnapshot.exists()){
Object sp = documentSnapshot.get("StorePrice");
if(sp != null){
p = Float.parseFloat(String.valueOf(sp));
}
Float totalprice1 = (q * p);
totalprice = totalprice1 - totalprice;
}
}
});
}
}
});
db.collection("UserProfile").document(user_id).collection("Cart")
.document(filteredData.get(position).getProductId()).delete()
.addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
Toast.makeText(i,"item deleted", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(i,Listviewcart.class);
i.startActivity(intent);
}
});
}
});
// downloading image //
if(filteredData.get(position).getImage_path() != null && !TextUtils.isEmpty(filteredData.get(position).getImage_path())){
Picasso.with(getApplicationContext()) //Context
.load(filteredData.get(position).getImage_path()) //URL/FILE
.fit()
.into(holder.image);//an ImageView Object to show the loaded image;
}
return convertView;
}
}
java类
public class Listviewcart extends AppCompatActivity {
FirebaseAuth mAuth;
String user_id = "",price;
ListView listView;
List<Model> ls_data;
CustomAdaptercartlist adapter;
ProgressDialog pd;
FirebaseFirestore db = FirebaseFirestore.getInstance();
TextView shopperpay;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_listviewcart);
setTitle("Wish List");
if(getSupportActionBar() != null){
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}
mAuth = FirebaseAuth.getInstance();
user_id = mAuth.getUid();
listView = findViewById(R.id.list);
shopperpay = findViewById(R.id.shopperpay);
ls_data=new ArrayList<>();
//============progress diologue=========//
pd = new ProgressDialog(this);
pd.setTitle("Please Wait...");
pd.setCancelable(false);
pd.show();
wishlistdata();
}
private void wishlistdata() {
db.collection("UserProfile").document(user_id).collection("Cart")
.get()
.addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
@SuppressLint("SetTextI18n")
@Override
public void onComplete(@NonNull Task<QuerySnapshot> task) {
if (task.isSuccessful() && !task.getResult().isEmpty()) {
for (final DocumentSnapshot document : task.getResult()) {
final String name = document.getString("ProductId");
String sid = document.getString("StoreId");
final String qty = document.getString("Quantity");
db.collection("Stores").document(sid).collection("Inventory").document(name).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
DocumentSnapshot document = task.getResult();
if (document.exists()) {
String ProductName = task.getResult().getString("ProductName");
Object ProductPrice = task.getResult().get("StorePrice");
if (ProductPrice != null) {
price = String.valueOf(ProductPrice);
}
String ProductImage = task.getResult().getString("Image");
if (ProductName != null && ProductPrice != null && ProductImage != null) {
Model m = new Model();
m.setName(ProductName);
m.setPrice(price);
m.setImage_path(ProductImage);
m.setProductId(name);
m.setqty(qty);
ls_data.add(m);
}
try {
adapter = new CustomAdaptercartlist(Listviewcart.this, ls_data, Listviewcart.this);
} catch (Exception ex) {
Log.e("Error", "Dashboard : " + ex);
}
listView.setAdapter(adapter);
pd.dismiss();
} else {
Log.e("firestore", "Error getting documents.", task.getException());
}
}
});
}
}
}
});
}
row_serach_iteam_cartlist
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
android:background="#EFE9EF">
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="10dp"
android:layout_marginEnd="10dp"
android:layout_marginTop="8dp"
android:orientation="horizontal"
android:padding="@dimen/activity_horizontal_margin"
app:cardCornerRadius="4dp"
android:elevation="2dp"
tools:targetApi="n">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_margin="10dp">
<ImageView
android:id="@+id/image"
android:layout_width="70dp"
android:layout_height="70dp"
android:src="@drawable/ic_action_placeholder"
android:scaleType="fitXY"
android:layout_marginEnd="8dp"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="@string/name"
android:textSize="14sp"
android:layout_marginStart="6dp"
android:layout_marginEnd="40dp"
android:textColor="#58595d"
android:id="@+id/name"
android:fontFamily="@font/poppinsmedium"
tools:targetApi="n"/>
<Button
android:id="@+id/delete"
android:layout_width="30dp"
android:layout_height="30dp"
android:background="@drawable/ic_action_delete"
android:textSize="14sp"
android:layout_alignParentEnd="true"
android:layout_marginStart="6dp"
android:layout_marginEnd="10dp"
android:textColor="#58595d"
android:fontFamily="@font/poppinsmedium"
tools:targetApi="n"/>
</RelativeLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_marginStart="6dp"
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fontFamily="@font/poppinsmedium" android:gravity="start"
android:text="Quantity :"
android:textAlignment="textStart"
android:textColor="#58595d"
android:textSize="14sp"
tools:targetApi="n" />
<TextView
android:id="@+id/quantity"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="4dp"
android:fontFamily="@font/poppinsregular"
android:gravity="start"
android:text="qty"
android:textAlignment="textStart"
android:textColor="#000000"
android:textSize="14sp"
tools:targetApi="n" />
</LinearLayout>
<TextView
android:id="@+id/price"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fontFamily="@font/poppinsmedium"
android:gravity="start"
android:text="qty"
android:textAlignment="textStart"
android:textColor="#000000"
android:textSize="14sp"
android:layout_marginStart="8dp"
tools:targetApi="n" />
<TextView
android:id="@+id/pq"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fontFamily="@font/poppinsmedium"
android:gravity="start"
android:text="total"
android:textAlignment="textStart"
android:textColor="#000000"
android:textSize="14sp"
android:layout_marginStart="8dp"
tools:targetApi="n" />
<TextView
android:id="@+id/ip"
android:visibility="gone"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:fontFamily="@font/poppinsmedium"
android:gravity="start"
android:textAlignment="textStart"
android:textColor="#000000"
android:textSize="14sp"
android:layout_marginStart="8dp"
tools:targetApi="n" />
</LinearLayout>
</LinearLayout>
</android.support.v7.widget.CardView>
</LinearLayout>
答案 0 :(得分：1)
我将举例说明。如果我对您的问题的理解有误，请纠正我。
假设您有一个名为 ItemsModel
的ModelClass
public class ItemsModel {
String itemName, itemUrl;
int price;
public ItemsModel(String itemName, String itemUrl, int price) {
this.itemName = itemName;
this.itemUrl = itemUrl;
this.price = price;
}
public String getItemName() {
return itemName;
}
public String getItemUrl() {
return itemUrl;
}
public int getPrice() {
return price;
}}
将所有已添加购物车的商品放入另一个模型类
public class CartModel {
String itemName, itemUrl;
int price, quantity;
public CartModel(String itemName, String itemUrl, int price, int quantity) {
this.itemName = itemName;
this.itemUrl = itemUrl;
this.price = price;
this.quantity = quantity;
}
public String getItemName() {
return itemName;
}
public String getItemUrl() {
return itemUrl;
}
public int getPrice() {
return price;
}
public int getQuantity() {
return quantity;
}}
因为您将在
ArrayList<CartModel> cartList中传递购物车项目。
int total = 0;
for(int i = 0; i < cartList.size(); i++){
int quantity = cartList.get(i).getQuantity();
int pricePerUnit = cartList.get(i).getPrice();
total = total + (pricePerUnit * quantity);
}
可变总计是所有农产品的总计。
希望这会有所帮助
答案 1 :(得分：0)
这是解决方案。在获取数据的同时在for循环中执行计算
private void wishlistdata() {
db.collection("UserProfile").document(user_id).collection("Cart")
.get()
.addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
@SuppressLint("SetTextI18n")
@Override
public void onComplete(@NonNull Task<QuerySnapshot> task) {
if (task.isSuccessful() && !task.getResult().isEmpty()) {
for (final DocumentSnapshot document : task.getResult()) {
final String name = document.getString("ProductId");
String sid = document.getString("StoreId");
final String qty = document.getString("Quantity");
db.collection("Stores").document(sid).collection("Inventory").document(name).get().addOnCompleteListener(new OnCompleteListener<DocumentSnapshot>() {
@Override
public void onComplete(@NonNull Task<DocumentSnapshot> task) {
DocumentSnapshot document = task.getResult();
if (document.exists()) {
String ProductName = task.getResult().getString("ProductName");
Object ProductPrice = task.getResult().get("StorePrice");
if (ProductPrice != null) {
price1 = String.valueOf(ProductPrice);
p = Float.valueOf(String.valueOf(ProductPrice));
}
String ProductImage = task.getResult().getString("Image");
if (ProductName != null && ProductPrice != null && ProductImage != null) {
Float a = p * Integer.parseInt(qty);
total = total + a;
shopperpay.setText(String.valueOf(total));
pd.dismiss();
}
} else {
pd.dismiss();
Log.e("firestore", "Error getting documents.", task.getException());
}
}
});
}
}
}
});
}