正如您从我的代码中看到的那样，我在这里完全错过了一个完整的概念。我的目标是让用户输入：
Jbutton 文本字段：文本方向和助记符
我将该信息传递给我的 Button 类，该类检查错误并返回一个已定义的按钮。
然后根据用户规范使用所述按钮填充 JFrame。
BASIC，显然是一个课程问题，但我在这里无能为力。这是我第一次寻求帮助，所以请放轻松。
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.JButton;
/**
* This class will create a button using the Button class and with user input to define the instance
* of the Button Class.
*
*/
public class CreateButton extends JPanel
{
// instance variables
private static String userIn; // user input
private static Button userButton; // button to be manipulated
public static JButton createdButton; // finished button
/**
* Contructor for the CreateButton class.
*/
public static void main (String [] args)
{
System.out.println("\nThis program will create a button with some input for you.");
System.out.println("What would you like to call this button?");
userIn = StringIn.get();
userButton = new Button();
userButton.buttonText(userIn);
System.out.println("\nYou can orient your text on the button in the vertical and");
System.out.println("horizontal axis. We will start with the vertical. Where would you like");
System.out.println("the text, on the top, center, or bottom?");
userIn = StringIn.get();
String vertical = userIn;
System.out.println("\nNext let's select the horizontal alignment. Would you like the text");
System.out.println("aligned to the left, center, or right?");
userIn = StringIn.get();
String horizontal = userIn;
userButton.textPosition(vertical,horizontal);
System.out.println("\nFinally let's add a mnemonic or hotkey to the button. Pick a letter");
System.out.println("from a-z on the keyboard and you can activate the button by pushing");
System.out.println("ALT + your letter of choice. Please enter your letter:");
userIn = StringIn.get();
userButton.buttonMnemomic(userIn);
System.out.println("\nGreat let's create and see this button.");
javax.swing.SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
createAndShowGUI();
}
});
}
private static void createAndShowGUI()
{
//Create and set up the window.
JFrame frame = new JFrame("Create a Button");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
CreateButton newContentPane = new CreateButton();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
//Display the window.
frame.pack();
frame.setVisible(true);
}
}
我的按钮错误检查器代码如下：
import javax.swing.AbstractButton;
import javax.swing.JButton;
/**
* This class will demonstrate the use of a button.
*
*/
public class Button
{
// instance variables
protected JButton myButton; // button to be created and manipulated
private String myButtonText; // text on the button
private String myButtonVerticalTextPosition;
private String myButtonHorizontalTextPosition;
private String myButtonMnemonic; // hotkey for the button
/**
* Constructor for objects of class Button
*/
public Button()
{
}
/**
*Set button text. String input.
*/
public void buttonText(String textIn)
{
myButtonText = textIn;
}
/**
*Set button text position. String input for vertical (top, center, bottom) and horizontal
*(left, center, right).
*/
public void textPosition(String verticalIn, String horizontalIn)
{
myButtonVerticalTextPosition = verticalIn;
boolean validInput = false;
do
{
if ((myButtonVerticalTextPosition.compareToIgnoreCase("top") == 0)||
(myButtonVerticalTextPosition.compareToIgnoreCase("centre") == 0) ||
(myButtonVerticalTextPosition.compareToIgnoreCase("center") == 0) ||
(myButtonVerticalTextPosition.compareToIgnoreCase("bottom") == 0))
{
validInput = true;
} else
{
System.out.println("\nPlease enter top, center, or bottom for vertical position:");
myButtonVerticalTextPosition = StringIn.get();
}
} while (validInput == false);
myButtonHorizontalTextPosition = horizontalIn;
validInput = false;
do
{
if ((myButtonHorizontalTextPosition.compareToIgnoreCase("left") == 0) ||
(myButtonHorizontalTextPosition.compareToIgnoreCase("centre") == 0) ||
(myButtonHorizontalTextPosition.compareToIgnoreCase("center") == 0) ||
(myButtonHorizontalTextPosition.compareToIgnoreCase("right") == 0))
{
validInput = true;
} else
{
System.out.println("\nPlease enter left, center, or right for horizontal position:");
myButtonHorizontalTextPosition = StringIn.get();
}
} while (validInput == false);
}
/**
*Set button mnemomic. String input for mnemomic [a-z].
*/
public void buttonMnemomic(String mnemomicIn)
{
myButtonMnemonic = mnemomicIn;
boolean validInput = false;
do
{
if (myButtonMnemonic.length() > 1)
{
System.out.println("\nPlease enter a letter from a-z: ");
myButtonMnemonic = StringIn.get();
} else if (!myButtonMnemonic.matches("^[a-zA-Z]+$"))
{
System.out.println("\nPlease enter a letter from a-z: ");
myButtonMnemonic = StringIn.get();
} else if ((myButtonMnemonic.length() == 1) &&
(myButtonMnemonic.matches("^[a-zA-Z]+$")))
{
validInput = true;
}
} while (validInput == false);
}
/**
*Create button. Void method to create the button to the variables provided.
*/
public void createButton()
{
// create new button
myButton = new JButton(myButtonText);
// set text position
switch (myButtonVerticalTextPosition)
{
case "top":
myButton.setVerticalTextPosition(AbstractButton.TOP);
break;
case "centre":
myButton.setVerticalTextPosition(AbstractButton.CENTER);
break;
case "center":
myButton.setVerticalTextPosition(AbstractButton.CENTER);
break;
case "bottom":
myButton.setVerticalTextPosition(AbstractButton.BOTTOM);
break;
default:
System.err.format("%n%s is an invalid entry.", myButtonVerticalTextPosition);
break;
}
switch (myButtonHorizontalTextPosition)
{
case "left":
myButton.setHorizontalTextPosition(AbstractButton.LEADING);
break;
case "centre":
myButton.setHorizontalTextPosition(AbstractButton.CENTER);
break;
case "center":
myButton.setHorizontalTextPosition(AbstractButton.CENTER);
break;
case "right":
myButton.setHorizontalTextPosition(AbstractButton.TRAILING);
break;
default:
System.err.format("%n%s is an invalid entry.", myButtonVerticalTextPosition);
break;
}
// set button mnemonic
StringBuilder hotKey = new StringBuilder("KeyEvent.VK_");
hotKey.append(myButtonMnemonic.toUpperCase());
myButton.setMnemonic(hotKey.charAt(0));
// set tool tip text
myButton.setToolTipText("Push the button. You know you want to.");
}
/**
*Returns a JButton for the button type.
*/
public JButton returnButton()
{
return myButton;
}
}
这一切都适用于您添加“createdButton”的部分。如果我将其设为默认按钮，它会通过动作并放置默认按钮。
仅供参考，这是我的 StringIn 代码：
import java.util.Scanner;
import java.io.IOException;
/**
* This class will allow the user to type in string from the console.
*
*/
public class StringIn
{
// instance variables
private static String userIn;
public static String get()
{
try (Scanner in = new Scanner(System.in))
{
userIn = new String(in.nextLine()); // Read the string from console.
}
return userIn;
}
}