Java android Spinner getSelection在android studio中出现错误
我正在尝试将firebase实时数据库添加到我的购物车片段中，我希望当有人单击“结帐”按钮时，他们应该重定向到结帐活动，并且他订购的产品应该转到firebase数据库。没有错误，但当我运行应用程序时。应用程序关闭，并且在log cat中出现此错误 LogCatJava android Spinner getSelection在android studio中出现错误,java,android,firebase,android-spinner,Java,Android,Firebase,Android Spinner,我正在尝试将firebase实时数据库添加到我的购物车片段中，我希望当有人单击“结帐”按钮时，他们应该重定向到结帐活动，并且他订购的产品应该转到firebase数据库。没有错误，但当我运行应用程序时。应用程序关闭，并且在log cat中出现此错误 LogCat 2021-04-07 05:14:29.398 8294-8294/com.example.naashtae E/xample.naashta: [qarth_debug:] get PatchStore::createDisableE
2021-04-07 05:14:29.398 8294-8294/com.example.naashtae E/xample.naashta: [qarth_debug:] get PatchStore::createDisableExceptionQarthFile method fail.
--------- beginning of crash
2021-04-07 05:14:29.400 8294-8294/com.example.naashtae E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.naashtae, PID: 8294
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Spinner.setSelection(int, boolean)' on a null object reference
at com.example.shoppingcart.models.CartItem.getSelectedSpinnerValue(CartItem.java:54)
at com.example.shoppingcart.views.CartFragment.confirm(CartFragment.java:138)
at com.example.shoppingcart.views.CartFragment$3.onClick(CartFragment.java:116)
at android.view.View.performClick(View.java:6659)
at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:1119)
at android.view.View.performClickInternal(View.java:6631)
at android.view.View.access$3100(View.java:790)
at android.view.View$PerformClick.run(View.java:26187)
at android.os.Handler.handleCallback(Handler.java:907)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:216)
at android.app.ActivityThread.main(ActivityThread.java:7625)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:524)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:987)
package com.example.shoppingcart.views;
import android.content.Intent; import android.os.Bundle;
import androidx.annotation.NonNull; import androidx.annotation.Nullable; import androidx.databinding.BindingAdapter; import androidx.fragment.app.Fragment; import androidx.lifecycle.Observer; import androidx.lifecycle.ViewModelProvider; import androidx.navigation.NavController; import androidx.navigation.Navigation; import androidx.recyclerview.widget.DividerItemDecoration;
import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.Button; import android.widget.Spinner; import android.widget.TextView;
import com.example.shoppingcart.R; import com.example.shoppingcart.adapters.CartListAdapter; import com.example.shoppingcart.cartholder; import com.example.shoppingcart.databinding.FragmentCartBinding; import com.example.shoppingcart.models.CartItem; import com.example.shoppingcart.viewmodels.ShopViewModel; import com.google.firebase.database.DatabaseReference; import com.google.firebase.database.FirebaseDatabase; import com.google.firebase.firestore.FirebaseFirestore;
import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.List; import java.util.UUID;
public class CartFragment extends Fragment implements CartListAdapter.CartInterface {
private static final String TAG = "CartFragment";
FirebaseFirestore firebaseFirestore;
public TextView productprice;
public Spinner productquantity;
Spinner spinner;
int quantity;
ShopViewModel shopViewModel;
FragmentCartBinding fragmentCartBinding;
NavController navController;
Button button;
private void finishActivity() {
if (getActivity() != null) {
getActivity().finish();
}
}
public CartFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
fragmentCartBinding = FragmentCartBinding.inflate(inflater, container, false);
firebaseFirestore = FirebaseFirestore.getInstance();
return fragmentCartBinding.getRoot();
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
navController = Navigation.findNavController(view);
final CartListAdapter cartListAdapter = new CartListAdapter(this);
fragmentCartBinding.cartRecyclerView.setAdapter(cartListAdapter);
fragmentCartBinding.cartRecyclerView.addItemDecoration(new DividerItemDecoration(requireContext(), DividerItemDecoration.VERTICAL));
shopViewModel = new ViewModelProvider(requireActivity()).get(ShopViewModel.class);
shopViewModel.getCart().observe(getViewLifecycleOwner(), new Observer<List<CartItem>>() {
@Override
public void onChanged(List<CartItem> cartItems) {
cartListAdapter.submitList(cartItems);
fragmentCartBinding.placeOrderButton.setEnabled(cartItems.size() > 0);
}
});
shopViewModel.getTotalPrice().observe(getViewLifecycleOwner(), new Observer<Double>() {
@Override
public void onChanged(Double aDouble) {
fragmentCartBinding.orderTotalTextView.setText("Total: PKR " + aDouble.toString());
String price=aDouble.toString().trim();
}
});
button = (Button) getView().findViewById(R.id.placeOrderButton);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
confirm();
}
});
}
public void confirm() {
productprice = getView().findViewById(R.id.orderTotalTextView);
final String saveCurrentDate, saveCurrentTime;
Calendar calForDate = Calendar.getInstance();
SimpleDateFormat currentDate = new SimpleDateFormat("MMM dd, yyyy");
saveCurrentDate = currentDate.format(calForDate.getTime());
SimpleDateFormat currentTime = new SimpleDateFormat("HH:mm:ss a");
saveCurrentTime = currentTime.format(calForDate.getTime());
String productPrice = productprice.toString().trim();
String productq= CartItem.getSelectedSpinnerValue(spinner,quantity).trim();
UUID uuid = UUID.randomUUID();
String randomUUIDString = uuid.toString().trim();
cartholder op = new cartholder(productPrice,productq, saveCurrentDate, saveCurrentTime);
FirebaseDatabase dab = FirebaseDatabase.getInstance();
DatabaseReference note = dab.getReference(randomUUIDString);
note.child("Products").setValue(op);
Intent intent = new Intent(CartFragment.this.getActivity(), CheckoutActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
finishActivity();
}
@Override
public void deleteItem(CartItem cartItem) {
shopViewModel.removeItemFromCart(cartItem);
}
@Override
public void changeQuantity(CartItem cartItem, int quantity) {
shopViewModel.changeQuantity(cartItem, quantity);
}
}
package com.example.shoppingcart.models;
import android.widget.Spinner;
import androidx.annotation.NonNull;
import androidx.databinding.BindingAdapter;
import androidx.recyclerview.widget.DiffUtil;
public class CartItem {
private Product product;
private int quantity;
public CartItem(Product product, int quantity) {
this.product = product;
this.quantity = quantity;
}
public Product getProduct() {
return product;
}
public void setProduct(Product product) {
this.product = product;
}
public int getQuantity() {
return quantity;
}
public void setQuantity(int quantity) {
this.quantity = quantity;
}
@Override
public String toString() {
return "CartItem{" +
"product=" + product +
", quantity=" + quantity +
'}';
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
CartItem cartItem = (CartItem) o;
return getQuantity() == cartItem.getQuantity() &&
getProduct().equals(cartItem.getProduct());
}
@BindingAdapter("android:setVal")
public static String getSelectedSpinnerValue(Spinner spinner, int quantity) {
spinner.setSelection(quantity - 1, true);
return spinner.getSelectedItem().toString();
}
public static DiffUtil.ItemCallback<CartItem> itemCallback = new DiffUtil.ItemCallback<CartItem>() {
@Override
public boolean areItemsTheSame(@NonNull CartItem oldItem, @NonNull CartItem newItem) {
return oldItem.getQuantity() == newItem.getQuantity();
}
@Override
public boolean areContentsTheSame(@NonNull CartItem oldItem, @NonNull CartItem newItem) {
return oldItem.equals(newItem);
}
};
}
package com.example.shoppingcart;
public class cartholder {
String productPrice,productq,Time,Date;
public cartholder( String productPrice,String productq, String time, String date) {
this.productPrice = productPrice;
this.productq=productq;
Time = time;
Date = date;
}
public String getProductPrice() {
return productPrice;
}
public void setProductPrice(String productPrice) {
this.productPrice = productPrice;
}
public String getProductq() {
return productq;
}
public void setProductq(String productq) {
this.productq = productq;
}
public String getTime() {
return Time;
}
public void setTime(String time) {
Time = time;
}
public String getDate() {
return Date;
}
public void setDate(String date) {
Date = date;
}
}
package com.example.shoppingcart.repositories;
import androidx.lifecycle.LiveData;
import androidx.lifecycle.MutableLiveData;
import com.example.shoppingcart.models.CartItem;
import com.example.shoppingcart.models.Product;
import java.util.ArrayList;
import java.util.List;
public class CartRepo {
private MutableLiveData<List<CartItem>> mutableCart = new MutableLiveData<>();
private MutableLiveData<Double> mutableTotalPrice = new MutableLiveData<>();
public LiveData<List<CartItem>> getCart() {
if (mutableCart.getValue() == null) {
initCart();
}
return mutableCart;
}
public void initCart() {
mutableCart.setValue(new ArrayList<CartItem>());
calculateCartTotal();
}
public boolean addItemToCart(Product product) {
if (mutableCart.getValue() == null) {
initCart();
}
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
for (CartItem cartItem: cartItemList) {
if (cartItem.getProduct().getId().equals(product.getId())) {
if (cartItem.getQuantity() == 5) {
return false;
}
int index = cartItemList.indexOf(cartItem);
cartItem.setQuantity(cartItem.getQuantity() + 1);
cartItemList.set(index, cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
return true;
}
}
CartItem cartItem = new CartItem(product, 1);
cartItemList.add(cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
return true;
}
public void removeItemFromCart(CartItem cartItem) {
if (mutableCart.getValue() == null) {
return;
}
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
cartItemList.remove(cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
}
public void changeQuantity(CartItem cartItem, int quantity) {
if (mutableCart.getValue() == null) return;
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
CartItem updatedItem = new CartItem(cartItem.getProduct(), quantity);
cartItemList.set(cartItemList.indexOf(cartItem), updatedItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
}
private void calculateCartTotal() {
if (mutableCart.getValue() == null) return;
double total = 0.0;
List<CartItem> cartItemList = mutableCart.getValue();
for (CartItem cartItem: cartItemList) {
total += cartItem.getProduct().getPrice() * cartItem.getQuantity();
}
mutableTotalPrice.setValue(total);
}
public LiveData<Double> getTotalPrice() {
if (mutableTotalPrice.getValue() == null) {
mutableTotalPrice.setValue(0.0);
}
return mutableTotalPrice;
}
}
package com.example.shoppingcart.adapters;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.DiffUtil;
import androidx.recyclerview.widget.ListAdapter;
import androidx.recyclerview.widget.RecyclerView;
import com.example.shoppingcart.databinding.CartRowBinding;
import com.example.shoppingcart.models.CartItem;
public class CartListAdapter extends ListAdapter<CartItem, CartListAdapter.CartVH> {
private CartInterface cartInterface;
public CartListAdapter(CartInterface cartInterface) {
super(CartItem.itemCallback);
this.cartInterface = cartInterface;
}
@NonNull
@Override
public CartVH onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
CartRowBinding cartRowBinding = CartRowBinding.inflate(layoutInflater, parent, false);
return new CartVH(cartRowBinding);
}
@Override
public void onBindViewHolder(@NonNull CartVH holder, int position) {
holder.cartRowBinding.setCartItem(getItem(position));
holder.cartRowBinding.executePendingBindings();
}
class CartVH extends RecyclerView.ViewHolder {
CartRowBinding cartRowBinding;
public CartVH(@NonNull CartRowBinding cartRowBinding) {
super(cartRowBinding.getRoot());
this.cartRowBinding = cartRowBinding;
cartRowBinding.deleteProductButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
cartInterface.deleteItem(getItem(getAdapterPosition()));
}
});
cartRowBinding.quantitySpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
int quantity = position + 1;
if (quantity == getItem(getAdapterPosition()).getQuantity()) {
return;
}
cartInterface.changeQuantity(getItem(getAdapterPosition()), quantity);
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
}
}
public interface CartInterface {
void deleteItem(CartItem cartItem);
void changeQuantity(CartItem cartItem, int quantity);
}
}
package com.example.shoppingcart.views;
import android.content.Intent; import android.os.Bundle;
import androidx.annotation.NonNull; import androidx.annotation.Nullable; import androidx.databinding.BindingAdapter; import androidx.fragment.app.Fragment; import androidx.lifecycle.Observer; import androidx.lifecycle.ViewModelProvider; import androidx.navigation.NavController; import androidx.navigation.Navigation; import androidx.recyclerview.widget.DividerItemDecoration;
import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.Button; import android.widget.Spinner; import android.widget.TextView;
import com.example.shoppingcart.R; import com.example.shoppingcart.adapters.CartListAdapter; import com.example.shoppingcart.cartholder; import com.example.shoppingcart.databinding.FragmentCartBinding; import com.example.shoppingcart.models.CartItem; import com.example.shoppingcart.viewmodels.ShopViewModel; import com.google.firebase.database.DatabaseReference; import com.google.firebase.database.FirebaseDatabase; import com.google.firebase.firestore.FirebaseFirestore;
import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.List; import java.util.UUID;
public class CartFragment extends Fragment implements CartListAdapter.CartInterface {
private static final String TAG = "CartFragment";
FirebaseFirestore firebaseFirestore;
public TextView productprice;
public Spinner productquantity;
Spinner spinner;
int quantity;
ShopViewModel shopViewModel;
FragmentCartBinding fragmentCartBinding;
NavController navController;
Button button;
private void finishActivity() {
if (getActivity() != null) {
getActivity().finish();
}
}
public CartFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
fragmentCartBinding = FragmentCartBinding.inflate(inflater, container, false);
firebaseFirestore = FirebaseFirestore.getInstance();
return fragmentCartBinding.getRoot();
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
navController = Navigation.findNavController(view);
final CartListAdapter cartListAdapter = new CartListAdapter(this);
fragmentCartBinding.cartRecyclerView.setAdapter(cartListAdapter);
fragmentCartBinding.cartRecyclerView.addItemDecoration(new DividerItemDecoration(requireContext(), DividerItemDecoration.VERTICAL));
shopViewModel = new ViewModelProvider(requireActivity()).get(ShopViewModel.class);
shopViewModel.getCart().observe(getViewLifecycleOwner(), new Observer<List<CartItem>>() {
@Override
public void onChanged(List<CartItem> cartItems) {
cartListAdapter.submitList(cartItems);
fragmentCartBinding.placeOrderButton.setEnabled(cartItems.size() > 0);
}
});
shopViewModel.getTotalPrice().observe(getViewLifecycleOwner(), new Observer<Double>() {
@Override
public void onChanged(Double aDouble) {
fragmentCartBinding.orderTotalTextView.setText("Total: PKR " + aDouble.toString());
String price=aDouble.toString().trim();
}
});
button = (Button) getView().findViewById(R.id.placeOrderButton);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
confirm();
}
});
}
public void confirm() {
productprice = getView().findViewById(R.id.orderTotalTextView);
final String saveCurrentDate, saveCurrentTime;
Calendar calForDate = Calendar.getInstance();
SimpleDateFormat currentDate = new SimpleDateFormat("MMM dd, yyyy");
saveCurrentDate = currentDate.format(calForDate.getTime());
SimpleDateFormat currentTime = new SimpleDateFormat("HH:mm:ss a");
saveCurrentTime = currentTime.format(calForDate.getTime());
String productPrice = productprice.toString().trim();
String productq= CartItem.getSelectedSpinnerValue(spinner,quantity).trim();
UUID uuid = UUID.randomUUID();
String randomUUIDString = uuid.toString().trim();
cartholder op = new cartholder(productPrice,productq, saveCurrentDate, saveCurrentTime);
FirebaseDatabase dab = FirebaseDatabase.getInstance();
DatabaseReference note = dab.getReference(randomUUIDString);
note.child("Products").setValue(op);
Intent intent = new Intent(CartFragment.this.getActivity(), CheckoutActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
finishActivity();
}
@Override
public void deleteItem(CartItem cartItem) {
shopViewModel.removeItemFromCart(cartItem);
}
@Override
public void changeQuantity(CartItem cartItem, int quantity) {
shopViewModel.changeQuantity(cartItem, quantity);
}
}
package com.example.shoppingcart.models;
import android.widget.Spinner;
import androidx.annotation.NonNull;
import androidx.databinding.BindingAdapter;
import androidx.recyclerview.widget.DiffUtil;
public class CartItem {
private Product product;
private int quantity;
public CartItem(Product product, int quantity) {
this.product = product;
this.quantity = quantity;
}
public Product getProduct() {
return product;
}
public void setProduct(Product product) {
this.product = product;
}
public int getQuantity() {
return quantity;
}
public void setQuantity(int quantity) {
this.quantity = quantity;
}
@Override
public String toString() {
return "CartItem{" +
"product=" + product +
", quantity=" + quantity +
'}';
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
CartItem cartItem = (CartItem) o;
return getQuantity() == cartItem.getQuantity() &&
getProduct().equals(cartItem.getProduct());
}
@BindingAdapter("android:setVal")
public static String getSelectedSpinnerValue(Spinner spinner, int quantity) {
spinner.setSelection(quantity - 1, true);
return spinner.getSelectedItem().toString();
}
public static DiffUtil.ItemCallback<CartItem> itemCallback = new DiffUtil.ItemCallback<CartItem>() {
@Override
public boolean areItemsTheSame(@NonNull CartItem oldItem, @NonNull CartItem newItem) {
return oldItem.getQuantity() == newItem.getQuantity();
}
@Override
public boolean areContentsTheSame(@NonNull CartItem oldItem, @NonNull CartItem newItem) {
return oldItem.equals(newItem);
}
};
}
package com.example.shoppingcart;
public class cartholder {
String productPrice,productq,Time,Date;
public cartholder( String productPrice,String productq, String time, String date) {
this.productPrice = productPrice;
this.productq=productq;
Time = time;
Date = date;
}
public String getProductPrice() {
return productPrice;
}
public void setProductPrice(String productPrice) {
this.productPrice = productPrice;
}
public String getProductq() {
return productq;
}
public void setProductq(String productq) {
this.productq = productq;
}
public String getTime() {
return Time;
}
public void setTime(String time) {
Time = time;
}
public String getDate() {
return Date;
}
public void setDate(String date) {
Date = date;
}
}
package com.example.shoppingcart.repositories;
import androidx.lifecycle.LiveData;
import androidx.lifecycle.MutableLiveData;
import com.example.shoppingcart.models.CartItem;
import com.example.shoppingcart.models.Product;
import java.util.ArrayList;
import java.util.List;
public class CartRepo {
private MutableLiveData<List<CartItem>> mutableCart = new MutableLiveData<>();
private MutableLiveData<Double> mutableTotalPrice = new MutableLiveData<>();
public LiveData<List<CartItem>> getCart() {
if (mutableCart.getValue() == null) {
initCart();
}
return mutableCart;
}
public void initCart() {
mutableCart.setValue(new ArrayList<CartItem>());
calculateCartTotal();
}
public boolean addItemToCart(Product product) {
if (mutableCart.getValue() == null) {
initCart();
}
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
for (CartItem cartItem: cartItemList) {
if (cartItem.getProduct().getId().equals(product.getId())) {
if (cartItem.getQuantity() == 5) {
return false;
}
int index = cartItemList.indexOf(cartItem);
cartItem.setQuantity(cartItem.getQuantity() + 1);
cartItemList.set(index, cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
return true;
}
}
CartItem cartItem = new CartItem(product, 1);
cartItemList.add(cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
return true;
}
public void removeItemFromCart(CartItem cartItem) {
if (mutableCart.getValue() == null) {
return;
}
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
cartItemList.remove(cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
}
public void changeQuantity(CartItem cartItem, int quantity) {
if (mutableCart.getValue() == null) return;
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
CartItem updatedItem = new CartItem(cartItem.getProduct(), quantity);
cartItemList.set(cartItemList.indexOf(cartItem), updatedItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
}
private void calculateCartTotal() {
if (mutableCart.getValue() == null) return;
double total = 0.0;
List<CartItem> cartItemList = mutableCart.getValue();
for (CartItem cartItem: cartItemList) {
total += cartItem.getProduct().getPrice() * cartItem.getQuantity();
}
mutableTotalPrice.setValue(total);
}
public LiveData<Double> getTotalPrice() {
if (mutableTotalPrice.getValue() == null) {
mutableTotalPrice.setValue(0.0);
}
return mutableTotalPrice;
}
}
package com.example.shoppingcart.adapters;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.DiffUtil;
import androidx.recyclerview.widget.ListAdapter;
import androidx.recyclerview.widget.RecyclerView;
import com.example.shoppingcart.databinding.CartRowBinding;
import com.example.shoppingcart.models.CartItem;
public class CartListAdapter extends ListAdapter<CartItem, CartListAdapter.CartVH> {
private CartInterface cartInterface;
public CartListAdapter(CartInterface cartInterface) {
super(CartItem.itemCallback);
this.cartInterface = cartInterface;
}
@NonNull
@Override
public CartVH onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
CartRowBinding cartRowBinding = CartRowBinding.inflate(layoutInflater, parent, false);
return new CartVH(cartRowBinding);
}
@Override
public void onBindViewHolder(@NonNull CartVH holder, int position) {
holder.cartRowBinding.setCartItem(getItem(position));
holder.cartRowBinding.executePendingBindings();
}
class CartVH extends RecyclerView.ViewHolder {
CartRowBinding cartRowBinding;
public CartVH(@NonNull CartRowBinding cartRowBinding) {
super(cartRowBinding.getRoot());
this.cartRowBinding = cartRowBinding;
cartRowBinding.deleteProductButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
cartInterface.deleteItem(getItem(getAdapterPosition()));
}
});
cartRowBinding.quantitySpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
int quantity = position + 1;
if (quantity == getItem(getAdapterPosition()).getQuantity()) {
return;
}
cartInterface.changeQuantity(getItem(getAdapterPosition()), quantity);
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
}
}
public interface CartInterface {
void deleteItem(CartItem cartItem);
void changeQuantity(CartItem cartItem, int quantity);
}
}
package com.example.shoppingcart.repositories；
导入androidx.lifecycle.LiveData；
导入androidx.lifecycle.MutableLiveData；
导入com.example.shoppingcart.models.CartItem；
导入com.example.shoppingcart.models.Product；
导入java.util.ArrayList；
导入java.util.List；
公共级CartRepo{
私有MutableLiveData mutableCart=新的MutableLiveData（）；
私有MutableLiveData mutableTotalPrice=新的MutableLiveData（）；
公共LiveData getCart（）{
if（mutableCart.getValue（）==null）{
initCart（）；
}
返回可变购物车；
}
public void initCart（）{
setValue（新的ArrayList（））；
calculateCartTotal（）；
}
公共布尔加法器（产品）{
if（mutableCart.getValue（）==null）{
initCart（）；
}
List cartItemList=新的ArrayList（mutableCart.getValue（））；
对于（CartItem CartItem:cartItemList）{
if（cartItem.getProduct（）.getId（）.equals（product.getId（）））{
如果（cartItem.getQuantity（）==5）{
返回false；
}
int index=cartItemList.indexOf（cartItem）；
cartItem.setQuantity（cartItem.getQuantity（）+1）；
cartItemList.set（索引，cartItem）；
mutableCart.setValue（cartItemList）；
calculateCartTotal（）；
返回true；
}
}
CartItem CartItem=新的CartItem（产品，1）；
cartItemList.add（cartItem）；
mutableCart.setValue（cartItemList）；
calculateCartTotal（）；
返回true；
}
公共无效removeItemFromCart（CartItem CartItem）{
if（mutableCart.getValue（）==null）{
返回；
}
List cartItemList=新的ArrayList（mutableCart.getValue（））；
cartItemList.remove（cartItem）；
mutableCart.setValue（cartItemList）；
calculateCartTotal（）；
}
公共无效变更数量（CartItem CartItem，整数数量）{
if（mutableCart.getValue（）==null）返回；
List cartItemList=新的ArrayList（mutableCart.getValue（））；
CartItem UpdateItem=新的CartItem（CartItem.getProduct（），数量）；
集合（cartItemList.indexOf（cartItem），UpdateItem）；
mutableCart.setValue（cartItemList）；
calculateCartTotal（）；
}
私有void calculateCartTotal（）{
if（mutableCart.getValue（）==null）返回；
双倍合计=0.0；
List cartItemList=mutableCart.getValue（）；
对于（CartItem CartItem:cartItemList）{
总计+=cartItem.getProduct（）.getPrice（）*cartItem.getQuantity（）；
}
可变TotalPrice.setValue（总计）；
}
公共LiveData getTotalPrice（）{
if（mutableTotalPrice.getValue（）==null）{
可变TotalPrice.setValue（0.0）；
}
返回可变总价；
}
}
package com.example.shoppingcart.views;
import android.content.Intent; import android.os.Bundle;
import androidx.annotation.NonNull; import androidx.annotation.Nullable; import androidx.databinding.BindingAdapter; import androidx.fragment.app.Fragment; import androidx.lifecycle.Observer; import androidx.lifecycle.ViewModelProvider; import androidx.navigation.NavController; import androidx.navigation.Navigation; import androidx.recyclerview.widget.DividerItemDecoration;
import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.Button; import android.widget.Spinner; import android.widget.TextView;
import com.example.shoppingcart.R; import com.example.shoppingcart.adapters.CartListAdapter; import com.example.shoppingcart.cartholder; import com.example.shoppingcart.databinding.FragmentCartBinding; import com.example.shoppingcart.models.CartItem; import com.example.shoppingcart.viewmodels.ShopViewModel; import com.google.firebase.database.DatabaseReference; import com.google.firebase.database.FirebaseDatabase; import com.google.firebase.firestore.FirebaseFirestore;
import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.List; import java.util.UUID;
public class CartFragment extends Fragment implements CartListAdapter.CartInterface {
private static final String TAG = "CartFragment";
FirebaseFirestore firebaseFirestore;
public TextView productprice;
public Spinner productquantity;
Spinner spinner;
int quantity;
ShopViewModel shopViewModel;
FragmentCartBinding fragmentCartBinding;
NavController navController;
Button button;
private void finishActivity() {
if (getActivity() != null) {
getActivity().finish();
}
}
public CartFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
fragmentCartBinding = FragmentCartBinding.inflate(inflater, container, false);
firebaseFirestore = FirebaseFirestore.getInstance();
return fragmentCartBinding.getRoot();
}
@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
navController = Navigation.findNavController(view);
final CartListAdapter cartListAdapter = new CartListAdapter(this);
fragmentCartBinding.cartRecyclerView.setAdapter(cartListAdapter);
fragmentCartBinding.cartRecyclerView.addItemDecoration(new DividerItemDecoration(requireContext(), DividerItemDecoration.VERTICAL));
shopViewModel = new ViewModelProvider(requireActivity()).get(ShopViewModel.class);
shopViewModel.getCart().observe(getViewLifecycleOwner(), new Observer<List<CartItem>>() {
@Override
public void onChanged(List<CartItem> cartItems) {
cartListAdapter.submitList(cartItems);
fragmentCartBinding.placeOrderButton.setEnabled(cartItems.size() > 0);
}
});
shopViewModel.getTotalPrice().observe(getViewLifecycleOwner(), new Observer<Double>() {
@Override
public void onChanged(Double aDouble) {
fragmentCartBinding.orderTotalTextView.setText("Total: PKR " + aDouble.toString());
String price=aDouble.toString().trim();
}
});
button = (Button) getView().findViewById(R.id.placeOrderButton);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
confirm();
}
});
}
public void confirm() {
productprice = getView().findViewById(R.id.orderTotalTextView);
final String saveCurrentDate, saveCurrentTime;
Calendar calForDate = Calendar.getInstance();
SimpleDateFormat currentDate = new SimpleDateFormat("MMM dd, yyyy");
saveCurrentDate = currentDate.format(calForDate.getTime());
SimpleDateFormat currentTime = new SimpleDateFormat("HH:mm:ss a");
saveCurrentTime = currentTime.format(calForDate.getTime());
String productPrice = productprice.toString().trim();
String productq= CartItem.getSelectedSpinnerValue(spinner,quantity).trim();
UUID uuid = UUID.randomUUID();
String randomUUIDString = uuid.toString().trim();
cartholder op = new cartholder(productPrice,productq, saveCurrentDate, saveCurrentTime);
FirebaseDatabase dab = FirebaseDatabase.getInstance();
DatabaseReference note = dab.getReference(randomUUIDString);
note.child("Products").setValue(op);
Intent intent = new Intent(CartFragment.this.getActivity(), CheckoutActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
startActivity(intent);
finishActivity();
}
@Override
public void deleteItem(CartItem cartItem) {
shopViewModel.removeItemFromCart(cartItem);
}
@Override
public void changeQuantity(CartItem cartItem, int quantity) {
shopViewModel.changeQuantity(cartItem, quantity);
}
}
package com.example.shoppingcart.models;
import android.widget.Spinner;
import androidx.annotation.NonNull;
import androidx.databinding.BindingAdapter;
import androidx.recyclerview.widget.DiffUtil;
public class CartItem {
private Product product;
private int quantity;
public CartItem(Product product, int quantity) {
this.product = product;
this.quantity = quantity;
}
public Product getProduct() {
return product;
}
public void setProduct(Product product) {
this.product = product;
}
public int getQuantity() {
return quantity;
}
public void setQuantity(int quantity) {
this.quantity = quantity;
}
@Override
public String toString() {
return "CartItem{" +
"product=" + product +
", quantity=" + quantity +
'}';
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
CartItem cartItem = (CartItem) o;
return getQuantity() == cartItem.getQuantity() &&
getProduct().equals(cartItem.getProduct());
}
@BindingAdapter("android:setVal")
public static String getSelectedSpinnerValue(Spinner spinner, int quantity) {
spinner.setSelection(quantity - 1, true);
return spinner.getSelectedItem().toString();
}
public static DiffUtil.ItemCallback<CartItem> itemCallback = new DiffUtil.ItemCallback<CartItem>() {
@Override
public boolean areItemsTheSame(@NonNull CartItem oldItem, @NonNull CartItem newItem) {
return oldItem.getQuantity() == newItem.getQuantity();
}
@Override
public boolean areContentsTheSame(@NonNull CartItem oldItem, @NonNull CartItem newItem) {
return oldItem.equals(newItem);
}
};
}
package com.example.shoppingcart;
public class cartholder {
String productPrice,productq,Time,Date;
public cartholder( String productPrice,String productq, String time, String date) {
this.productPrice = productPrice;
this.productq=productq;
Time = time;
Date = date;
}
public String getProductPrice() {
return productPrice;
}
public void setProductPrice(String productPrice) {
this.productPrice = productPrice;
}
public String getProductq() {
return productq;
}
public void setProductq(String productq) {
this.productq = productq;
}
public String getTime() {
return Time;
}
public void setTime(String time) {
Time = time;
}
public String getDate() {
return Date;
}
public void setDate(String date) {
Date = date;
}
}
package com.example.shoppingcart.repositories;
import androidx.lifecycle.LiveData;
import androidx.lifecycle.MutableLiveData;
import com.example.shoppingcart.models.CartItem;
import com.example.shoppingcart.models.Product;
import java.util.ArrayList;
import java.util.List;
public class CartRepo {
private MutableLiveData<List<CartItem>> mutableCart = new MutableLiveData<>();
private MutableLiveData<Double> mutableTotalPrice = new MutableLiveData<>();
public LiveData<List<CartItem>> getCart() {
if (mutableCart.getValue() == null) {
initCart();
}
return mutableCart;
}
public void initCart() {
mutableCart.setValue(new ArrayList<CartItem>());
calculateCartTotal();
}
public boolean addItemToCart(Product product) {
if (mutableCart.getValue() == null) {
initCart();
}
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
for (CartItem cartItem: cartItemList) {
if (cartItem.getProduct().getId().equals(product.getId())) {
if (cartItem.getQuantity() == 5) {
return false;
}
int index = cartItemList.indexOf(cartItem);
cartItem.setQuantity(cartItem.getQuantity() + 1);
cartItemList.set(index, cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
return true;
}
}
CartItem cartItem = new CartItem(product, 1);
cartItemList.add(cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
return true;
}
public void removeItemFromCart(CartItem cartItem) {
if (mutableCart.getValue() == null) {
return;
}
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
cartItemList.remove(cartItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
}
public void changeQuantity(CartItem cartItem, int quantity) {
if (mutableCart.getValue() == null) return;
List<CartItem> cartItemList = new ArrayList<>(mutableCart.getValue());
CartItem updatedItem = new CartItem(cartItem.getProduct(), quantity);
cartItemList.set(cartItemList.indexOf(cartItem), updatedItem);
mutableCart.setValue(cartItemList);
calculateCartTotal();
}
private void calculateCartTotal() {
if (mutableCart.getValue() == null) return;
double total = 0.0;
List<CartItem> cartItemList = mutableCart.getValue();
for (CartItem cartItem: cartItemList) {
total += cartItem.getProduct().getPrice() * cartItem.getQuantity();
}
mutableTotalPrice.setValue(total);
}
public LiveData<Double> getTotalPrice() {
if (mutableTotalPrice.getValue() == null) {
mutableTotalPrice.setValue(0.0);
}
return mutableTotalPrice;
}
}
package com.example.shoppingcart.adapters;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.DiffUtil;
import androidx.recyclerview.widget.ListAdapter;
import androidx.recyclerview.widget.RecyclerView;
import com.example.shoppingcart.databinding.CartRowBinding;
import com.example.shoppingcart.models.CartItem;
public class CartListAdapter extends ListAdapter<CartItem, CartListAdapter.CartVH> {
private CartInterface cartInterface;
public CartListAdapter(CartInterface cartInterface) {
super(CartItem.itemCallback);
this.cartInterface = cartInterface;
}
@NonNull
@Override
public CartVH onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext());
CartRowBinding cartRowBinding = CartRowBinding.inflate(layoutInflater, parent, false);
return new CartVH(cartRowBinding);
}
@Override
public void onBindViewHolder(@NonNull CartVH holder, int position) {
holder.cartRowBinding.setCartItem(getItem(position));
holder.cartRowBinding.executePendingBindings();
}
class CartVH extends RecyclerView.ViewHolder {
CartRowBinding cartRowBinding;
public CartVH(@NonNull CartRowBinding cartRowBinding) {
super(cartRowBinding.getRoot());
this.cartRowBinding = cartRowBinding;
cartRowBinding.deleteProductButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
cartInterface.deleteItem(getItem(getAdapterPosition()));
}
});
cartRowBinding.quantitySpinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
int quantity = position + 1;
if (quantity == getItem(getAdapterPosition()).getQuantity()) {
return;
}
cartInterface.changeQuantity(getItem(getAdapterPosition()), quantity);
}
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
}
}
public interface CartInterface {
void deleteItem(CartItem cartItem);
void changeQuantity(CartItem cartItem, int quantity);
}
}
package com.example.shoppingcart.adapters；
导入android.view.LayoutInflater；
导入android.view.view；
导入android.view.ViewGroup；
导入android.widget.AdapterView；
导入androidx.annotation.NonNull；
导入androidx.recyclerview.widget.DiffUtil；
导入androidx.recyclerview.widget.ListAdapter；
导入androidx.recyclerview.widget.recyclerview；
导入com.example.shoppingcart.databinding.CartRowBinding；
导入com.example.shoppingcart.models.CartItem；
公共类CartListAdapter扩展ListAdapter{
专用CartInterface CartInterface；
公共CartListAdapter（CartInterface CartInterface）{
super（CartItem.itemCallback）；
this.cartInterface=cartInterface；
}
@非空
@凌驾
公共CartVH onCreateViewHolder（@NonNull ViewGroup parent，int viewType）{
LayoutInflater LayoutInflater=LayoutInflater.from（parent.getContext（））；
CartRowBinding CartRowBinding=CartRowBinding.inflate（LayoutFlater，parent，false）；
返回新CartVH（cartRowBinding）；
}
@凌驾
公共无效onBindViewHolder（@NonNull CartVH holder，int位置）{
holder.cartRowBinding.setCartItem（getItem（position））；
holder.cartRowBinding.executePendingBindings（）；
}
类别CartVH扩展了RecyclerView.ViewHolder{
CartRowBinding CartRowBinding；
公共CartVH（@NonNull CartRowBinding CartRowBinding）{
super（cartRowBinding.getRoot（））；
this.cartRowBinding=cartRowBinding；
cartRowBinding.deleteProductButton.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图v）{
cartInterface.deleteItem（getItem（getAdapterPosition（））；
}
});
cartRowBinding.quantitySpinner.setOnItemSelectedListener（新的AdapterView.OnItemSelectedListener（）{
@凌驾
已选择公共视图（AdapterView父视图、视图视图、整型位置、长id）{
整数数量=位置+1；
如果（数量==getItem（getAdapterPosition（））.getQuantity（））{
返回；
}
cartInterface.changeQuantity（getItem（getAdapterPosition（）），数量）；
}
@凌驾
未选择公共无效（AdapterView父级）{
}
});
}
}
公共接口CartInterface{
无效删除项（CartIte）