Question

抱歉非特定的标题。所以，我正在开发一个名为JustJava的应用程序，我刚刚安装了生奶油复选框和相应的代码。我记录了它，由于某种原因它没有显示出来。相反，它给了我错误，如：

无法加载memetrack模块

无法获取内存消耗信息：-1

无默认活动

此外，每次运行时，应用程序都会崩溃一次，就在开始时，我必须再次运行应用程序。显然，鲜奶油复选框没有更新任何东西。我已多次查看代码并在互联网上搜索了一段时间，但我找不到任何东西。有人可以看看我的代码，看看他们是否可以看到这个问题？

非常感谢！

XML布局代码

<EditText
    android:id="@+id/name_input"
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:hint="Enter Your Name Here"
    android:layout_marginBottom="16dp"
    android:inputType="text"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Toppings"
    android:layout_marginBottom="16dp"
    android:textAllCaps="true"
    android:textSize="20sp"/>

<CheckBox
    android:id="@+id/whipped_cream_checkbox"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Whipped cream"
    android:paddingLeft="24dp"
    android:textSize="16sp"
    android:textAppearance="?android:textAppearanceMedium" />

<CheckBox
    android:id="@+id/chocolate_checkbox"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Chocolate"
    android:paddingLeft="24dp"
    android:textSize="16sp"
    android:textAppearance="?android:textAppearanceMedium"
    android:layout_marginBottom="16dp"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginBottom="16dp"
    android:text="Quantity"
    android:textAllCaps="true"
    android:textSize="20sp"/>

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

<Button
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:onClick="decrement"
    android:text="-" />

<TextView
    android:id="@+id/quantity_text_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginLeft="8dp"
    android:layout_marginRight="8dp"
    android:text="0"
    android:textColor="@android:color/black"
    android:textSize="16sp" />

<Button
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:onClick="increment"
    android:text="+" />

</LinearLayout>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="16dp"
    android:text="Order summary"
    android:textSize="20sp"
    android:textAllCaps="true" />

<TextView
    android:id="@+id/order_summary_text_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="16dp"
    android:text="Free"
    android:textColor="@android:color/black"
    android:textSize="16sp" />

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="16dp"
    android:onClick="submitOrder"
    android:text="Order" />

MainActivity Code

package com.example.android.justjava3;

import android.icu.text.NumberFormat;
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.TextView;
import com.example.android.justjava.R;

/**

This app displays an order form to order coffee.
*/
public class MainActivity extends AppCompatActivity {

int quantity = 0;

@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) {
CheckBox whippedCreamCheckBox = (CheckBox) 
findViewById(R.id.whipped_cream_checkbox);
boolean hasWhippedCream = whippedCreamCheckBox.isChecked();
Log.v(“MainActivity”, “Has whipped cream?”+hasWhippedCream);
int price=calculatePrice();
String priceMessage=createOrderSummary(price, hasWhippedCream);
displayMessage(priceMessage);
}
/**
Calculates the price of the order.
@total price
*/
private int calculatePrice() {
int price = quantity * 5;
return price;
}
private String createOrderSummary(int price, boolean addWhippedCream){
String priceMessage=“The total price for " + quantity + " cups of coffee is 
$” + price;
priceMessage +="\n Customer name: Kaptain Kunal";
priceMessage +="\n Whipped cream topping: " + addWhippedCream;
String freeMessage=“Free”;
displayMessage(freeMessage);
priceMessage+="\n Number of coffees ordered: "+quantity;
return priceMessage;

}

/**

This method displays the given quantity value on the screen.
/
private void displayQuantity(int number) {
TextView quantityTextView = (TextView) 
findViewById(R.id.quantity_text_view);
quantityTextView.setText("" + number);
}
/*
This method displays the given price on the screen.
*/
private void displayMessage(String message) {
TextView orderSummaryTextView = (TextView) 
findViewById(R.id.order_summary_text_view);
orderSummaryTextView.setText
(NumberFormat.getCurrencyInstance().format(message));

}

public void increment (View view){

 quantity=(quantity+1);
 displayQuantity(quantity);
}

public void decrement (View view){
quantity=(quantity-1);
displayQuantity(quantity);
}

}

Answer 1

您似乎忘了在Manifest.xml中定义活动。像这样尝试一次

 <application>
    <activity
        android:name="ActivityName"
        android:screenOrientation="portrait"
        android:theme="@style/SplashTheme">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
 </application>

由于有关问题的有限详细信息，如果解决方案不起作用，则添加错误stackTrace以及问题。

我的应用程序中有很多错误

1 个答案: