Question

当这个程序运行时，它应该在我输入之后列出数字，但它只输入第一个我放的5，我缺少什么

public class Numbers extends JFrame
    {

         private JTextField textField;
         private JTextArea textArea, displayArea, finalArea;
         private JPanel controlPanel, bottomPanel, southPanel, displayPanel, displayFinal;
         private JButton enter, finalNumbers;
         private String input; 
         private int intInput;
         private int[] array = new int[5];

         private int entered = 0;

    public static void main(){
        Numbers myFrame = new Numbers();
        myFrame.setSize(600,600);
        myFrame.setTitle("Numbers between 10-100 by Daniel Bendlin");
        myFrame.createGUI(); 
        myFrame.pack();
        myFrame.setVisible(true);

    }


    public void createGUI()
    {
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        Container window = getContentPane();
        window.setLayout(new BorderLayout());

        controlPanel = new JPanel();
        controlPanel.setLayout(new FlowLayout());

        bottomPanel = new JPanel();
        bottomPanel.setLayout(new FlowLayout(FlowLayout.CENTER));


        southPanel = new JPanel();
        displayPanel = new JPanel();

        textArea = new JTextArea("Please enter 5 numbers between 10-100");
        textArea.setBackground(Color.white);
        displayArea = new JTextArea("");
        finalArea = new JTextArea("");

        textField = new JTextField(2);
        textField.setBackground(Color.white);

        enter = new JButton("Enter");
        enter.setBackground(Color.GREEN);
        enter.addActionListener(new EnterNum());
        finalNumbers = new JButton("Display Final Numbers");
        finalNumbers.addActionListener(new DisplayNum());

        controlPanel.add(textArea);
        southPanel.add(textField);
        southPanel.add(enter);
        displayPanel.add(displayArea);
        displayPanel.add(finalNumbers);
        displayPanel.add(finalArea);

        window.add(controlPanel,BorderLayout.NORTH);              
        window.add(southPanel,BorderLayout.CENTER);
        window.add(displayPanel,BorderLayout.SOUTH);
        textField.requestFocusInWindow();

    }
private class EnterNum implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {  

            input = textField.getText();
            intInput = Integer.parseInt(input);

            while (entered < array.length){

                try{

                    if((intInput >= 10) && (intInput <= 100)){

                        for(int i = 0; i < array.length; i++){

                            array[i] = intInput;
                            entered = entered + 1;
                            textField.setText("");
                            displayArea.setText("Entered number(s)..." + array[i]);
                         }                  
                        }else{
                            displayArea.setText("Input numbers that range between 10 and 100");
                        }
            }catch (NumberFormatException x){displayArea.setText("\"" + textField.getText() + "\" is not a legal number.");

            textField.selectAll();
            textField.requestFocus();
                                        }

           } 
       }
    }
    private class DisplayNum implements ActionListener
    {
        public void actionPerformed(ActionEvent e)
        {
            String intInput = String.valueOf(array[0]);
            finalArea.setText("\n" + intInput);
        }

    }
}

Answer 1

您的代码存在一些问题。我不确定是否可以列出所有这些，首先，如果您希望将代码作为Java应用程序运行，则主要方法应该采用String数组参数，即

public static void main(String[] args){
}

其次，您的while方法中没有for和actionPerformed(ActionEvent e)循环。

DisplayNum类中的actionPerformed（ActionEvent e）方法仅显示数组的第一个元素。也许你想连接所有5个数字并显示？无论如何，这是带有修改的代码：

public class Numbers extends JFrame {

    private JTextField textField;
    private JTextArea textArea, displayArea, finalArea;
    private JPanel controlPanel, bottomPanel, southPanel, displayPanel,
            displayFinal;
    private JButton enter, finalNumbers;
    private String input;
    private int intInput;
    private int[] array = new int[5];

    private int entered = 0;

    public static void main(String[] args) {
        Numbers myFrame = new Numbers();
        myFrame.setSize(600, 600);
        myFrame.setTitle("Numbers between 10-100 by Daniel Bendlin");
        myFrame.createGUI();
        myFrame.pack();
        myFrame.setVisible(true);

    }

    public void createGUI() {
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        Container window = getContentPane();
        window.setLayout(new BorderLayout());

        controlPanel = new JPanel();
        controlPanel.setLayout(new FlowLayout());

        bottomPanel = new JPanel();
        bottomPanel.setLayout(new FlowLayout(FlowLayout.CENTER));

        southPanel = new JPanel();
        displayPanel = new JPanel();

        textArea = new JTextArea("Please enter 5 numbers between 10-100");
        textArea.setBackground(Color.white);
        displayArea = new JTextArea("");
        finalArea = new JTextArea("");

        textField = new JTextField(2);
        textField.setBackground(Color.white);

        enter = new JButton("Enter");
        enter.setBackground(Color.GREEN);
        enter.addActionListener(new EnterNum());
        finalNumbers = new JButton("Display Final Numbers");
        finalNumbers.addActionListener(new DisplayNum());

        controlPanel.add(textArea);
        southPanel.add(textField);
        southPanel.add(enter);
        displayPanel.add(displayArea);
        displayPanel.add(finalNumbers);
        displayPanel.add(finalArea);

        window.add(controlPanel, BorderLayout.NORTH);
        window.add(southPanel, BorderLayout.CENTER);
        window.add(displayPanel, BorderLayout.SOUTH);
        textField.requestFocusInWindow();

    }

    private class EnterNum implements ActionListener {
        public void actionPerformed(ActionEvent e) {

            input = textField.getText();
            intInput = Integer.parseInt(input);

            if (entered < array.length) {

                try {

                    if ((intInput >= 10) && (intInput <= 100)) {
                        array[entered] = intInput;  
                        textField.setText("");
                        displayArea.setText("Entered number(s)..."
                                + array[entered]);
                        entered = entered + 1;
                } else {
                        displayArea
                                .setText("Input numbers that range between 10 and 100");
                    }
                } catch (NumberFormatException x) {
                    displayArea.setText("\"" + textField.getText()
                            + "\" is not a legal number.");

                    textField.selectAll();
                    textField.requestFocus();
                }

            }
        }
    }

    private class DisplayNum implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            StringBuffer sb = new StringBuffer();
            for (int i = 0; i < array.length; i++) {
                sb.append(String.valueOf(array[i]));
                if(i < array.length){
                    sb.append(",");
                }
            }
            finalArea.setText("\n" + sb.toString());
        }

    }
}

Answer 2

在您的DisplayNum课程中，您只显示array[0]。如果要显示多个，则需要使用某种循环：

for(int i = 0; i < array.length; i++) {
    // Do stuff with array[i] instead of array[0] here
}

Answer 3

您的数组大小设置为5，因此只能存在五个元素。

Answer 4

String intInput = String.valueOf（array [0]）;

在执行方法操作时，你已经传递了数组[o]，我认为你应该使用数组。

Answer 5

lass DisplaYEnum方法不正确。您没有正确创建displayArray。

见下文。

private class DisplayNum implements ActionListener {
    public void actionPerformed(ActionEvent e) {
        String intInput = "";
        for (int i = 0; i < array.length; i++) {
            intInput = intInput.concat(" " + String.valueOf(array[i]));
        }

        finalArea.setText("\n" + intInput);
    }

}

我的计划缺乏一步！请看看你能找到我所缺少的东西吗？

5 个答案: