我来回试图获取我的咖啡订购应用程序的数量和价格数字，以便正确显示。
自从我添加了我的Intent代码以便将我的订单摘要传递给电子邮件应用程序后，他们就变得很糟糕。我尝试的每个修复都修复了一个或另一个，但从来没有。
如果有人能够看一遍并帮我弄清楚错误的位置，那将非常感激。我认为问题在于区分数量和列出的数量。
/**
* IMPORTANT: Make sure you are using the correct package name.
* This example uses the package name:
* package com.example.android.justjava
* If you get an error when copying this code into Android studio, update it to match teh package name found
* in the project's AndroidManifest.xml file.
**/
package com.example.android.justjava;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
/**
* This app displays an order form to order coffee.
*/
public class MainActivity extends AppCompatActivity {
int listedQuantity = 2;
int price;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
/**
* This method is called when the order button is clicked.
*/
public void submitOrder(View view) {
// String message = createOrderSummary(listedQuantity);
// displayQuantityPrice(message);
Intent intent = new Intent(Intent.ACTION_SEND);
intent.setType("*/*");
intent.putExtra(Intent.EXTRA_SUBJECT, emailSubject());
intent.putExtra(Intent.EXTRA_TEXT, createOrderSummary(price));
if (intent.resolveActivity(getPackageManager()) != null) {
startActivity(intent);
}
}
private String emailSubject(){
String subjectText;
subjectText = "Coffee Order";
return subjectText;
}
/**
* Creates an order summary.
*
* @param quantity is the number of cups of coffee ordered
*/
private String createOrderSummary(int quantity) {
//find the checkbox here
//make a boolean variable
// set boolean variable to state of checkbox using isChecked()
price = calculatePrice(quantity);
String priceMessage ="Name: " + customersName();
priceMessage = priceMessage + "\nAdd whipped cream? " + hasWhippedCream();
priceMessage = priceMessage + "\nAdd chocolate? " + hasChocolate();
priceMessage = priceMessage + "\nQuantity: " + listedQuantity;
priceMessage = priceMessage + "\nTotal: $" + price;
priceMessage = priceMessage + "\nThank You!";
return priceMessage;
}
private boolean hasChocolate() {
boolean hasChocolate;
CheckBox chocolateCheckBox = findViewById(R.id.chocolate_check_box);
hasChocolate = chocolateCheckBox.isChecked();
return (hasChocolate);
}
public boolean hasWhippedCream() {
boolean hasWhippedCream;
CheckBox creamCheckBox = findViewById(R.id.cream_check_box);
hasWhippedCream = creamCheckBox.isChecked();
Log.v("MainActivity", "Add whipped cream? " + hasWhippedCream);
return(hasWhippedCream);
}
private String customersName() {
String customersName;
EditText nameEditText = (EditText) findViewById(R.id.name_edit_text);
customersName = nameEditText.getText().toString();
return(customersName);
}
/** These method is supposed to modify calculatePrice to include results for whipped cream
* and chocolate.
*/
/**
* Displays full order summary.
*/
private int calculatePrice(int quantity) {
boolean hasWhippedCream;
boolean hasChocolate;
if (hasWhippedCream() && hasChocolate()) {
return listedQuantity * 8;
}else if (hasChocolate()){
return listedQuantity * 7;
}else if (hasWhippedCream()){
return listedQuantity * 6;
}
return listedQuantity * 5;
}
/*** This method is called when the increment button is clicked.*/
public void increment(View view) {
if (listedQuantity == 100) {
Toast.makeText(this, "you cannot have more than 100 cups of coffee", Toast.LENGTH_SHORT).show();
return;
}listedQuantity = listedQuantity + 1;
displayQuantity(listedQuantity);
}
/*** This method is called when the decrement button is clicked.*/
public void decrement(View view) {
if (listedQuantity == 1) {
Toast.makeText(this, "you cannot have less than 1 cup ofcoffee", Toast.LENGTH_SHORT).show();
return;
}listedQuantity = listedQuantity - 1;
displayQuantity(listedQuantity);
}
/*** This method displays the given quantity value on the screen.*/
private void displayQuantity(int amount) {
TextView quantityTextView = (TextView) findViewById(R.id.quantity_text_view);
quantityTextView.setText("" + amount);
}
/*** This method displays the given price on the screen.*/
private void displayQuantityPrice(String message) {
TextView orderSummaryTextView = (TextView) findViewById(R.id.order_summary_text_view);
orderSummaryTextView.setText(message);
}
private void displayMessage(String message) {
TextView orderSummaryTextView = findViewById(R.id.order_summary_text_view);
orderSummaryTextView.setText(message);
}
我的订单摘要应该显示数量大于0的数字和数量的数字*咖啡杯及其配料的价格。起初价格总是0，但数量是正确的。为了解决这个问题，我尝试在第118行替换代码中的所有数量，除了[private int calculatePrice（int quantity）]。这样就修改了价格以显示正确的数字，但它将我的数量显示为0.然后我改变了在第118行的数量上市数量认为这是错误，但只是将两个数字都设置为0.我在整个课程中一直在研究这个应用程序，我不记得为什么我做了数量和列出数量两个不同变量，但我知道这是一个重要原因。真正奇怪的是，在我将一个intent放入我的submitOrder方法之前，这个错误永远不会出现。