Question

我目前正在为我的学校制作一个点数系统，它从数据库中提取数据并将其显示在DataPanel（JPanel的子类）中，该子类填充了Student类，每个类都是单独的单元格。这也是JPanel的子类。我之所以不使用JTable，是因为它不能满足我的审美需求。无论如何，当我只是将Student类添加到DataPanel时，它工作正常，但是，当我尝试通过创建一个具有布局BorderLayout的父JPanel并添加West上的复选框和中心的Student时添加JCheckBox，它只显示一个单元格，即使DataPanel的大小应该包含数据库中的所有数据。以下是一些图片和代码：

以下是DataPanel类的代码：

class DataPanel extends JPanel{
static Student[] students;
public DataPanel(String[][] data) {
    try{setLayout(new GridLayout(data.length,1));} catch(Exception e) { 
        GUI.control.updateUI();
        JOptionPane.showMessageDialog(null, "The search criteria you have entered is incorrect and did not generate any outcome.", "Invalid Search Criteria", JOptionPane.ERROR_MESSAGE);
    }
    setPreferredSize(new Dimension(382,data.length*20));
    students = new Student[data.length-1];
    JPanel parent = new JPanel(new BorderLayout());
    for(int i = 0; i < data.length; i++) {
        Student contents = new Student();
        JLabel[] labels = new JLabel[4];
        for(int x = 0; x < data[0].length; x++) {
            JLabel cur = new JLabel(" "+data[i][x]);
            cur.setFont(new Font("Arial", Font.PLAIN,12));
            labels[x] = cur;
            //System.out.println(data[0].length);

            contents.add(cur);

        }

        contents.setId(labels[0]);
        contents.setName(labels[1]);
        contents.setForm(labels[2]);
        contents.setPoints(labels[3]);
        contents.setParent(parent);
        JCheckBox box = new JCheckBox();

        contents.setCheckBox(box);

        parent.setBorder(BorderFactory.createLineBorder(Color.lightGray));
        parent.add("Center", contents);
        parent.add("West", box);
        add(contents); // >> parent = only one showing?
        System.out.println(i);
        if(i == 0) {
            parent.setBackground(new Color(200,200,255));
        }
        if(i != 0) {
            students[i-1] = contents;
        }
    }
}

public static void refresh() {
    for(Student i: students) {
        if(i != Student.getSelected()) {
        i.setBackground(Color.white); 
        }
    }

}

}

和学生班：

class Student extends JPanel implements MouseListener {
JLabel name;
JLabel id;
JLabel points;
JLabel form;
JCheckBox box;
JPanel parent;

private static Student selected;

public Student() {
    super(new GridLayout());
    addMouseListener(this);
}

public void setParent(JPanel parent) {
    this.parent = parent;
    parent.setBackground(Color.white);
}

public void setCheckBox(JCheckBox box) {
    this.box = box;
}
public void setName(JLabel name) {
    this.name = name;
}

public void setId(JLabel id) {
    this.id = id;
}

public void setPoints(JLabel points) {
    this.points = points;
}

public void setForm(JLabel form) {
    this.form = form;
}

@Override
public void mouseClicked(MouseEvent e) {
    if(name.getText().equals(" Student")) {
        parent.setBackground(new Color(200,200,255));
        return;
    }
    parent.setBackground(new Color(255,255,190));
    setSelected(this);
    DataPanel.refresh();
}

@Override
public void mouseEntered(MouseEvent e) {
    if(name.getText().equals(" Student")) {
        parent.setBackground(new Color(200,200,255));
        return;
    }
    if(this == getSelected()) {
        parent.setBackground(new Color(255,255,190));
    } else {
    parent.setBackground(new Color(230,230,255));
    }

}

@Override
public void mouseExited(MouseEvent e) {
    if(name.getText().equals(" Student")) {
        parent.setBackground(new Color(200,200,255));
        return;
    }
    if(this == getSelected()) {
        parent.setBackground(new Color(255,255,210));
    } else {
    parent.setBackground(Color.white); 
    }
}

@Override
public void mousePressed(MouseEvent e) {

}

@Override
public void mouseReleased(MouseEvent e) {

}

public static Student getSelected() {
    return selected;
}

public static void setSelected(Student selected) {
    Student.selected = selected;
}

}

提前感谢您的帮助，并告诉我您是否需要更多信息......

哦，顺便说一句，不注意实际的数据，只是出于测试目的：）

编辑：只有当我将parent（JPanel）添加到DataPanel而不是contents（JPanel）时才会出现问题。

Answer 1

我找到了答案。实际上非常愚蠢。

嗯，基本上，我有JPanel＆＃39; parent＆＃39;的构造函数。外部 for循环，因此它只创建一个并将全部数据添加到JPanel中。这就是为什么只有一个出现的原因。感谢所有试图帮助我的人。遗憾。

JPanel中只显示一个项目？

1 个答案: