java - 更改单个 JOptionPane 大小

Question

我需要帮助更改文本字段的大小。我在面板的开头有一个 JScrollPane (它很大，所以我可以读取更多数据)，然后我有一个用于说明的 JLabel，最后我想添加一个 JTextArea，我只需要一行来输入数字。问题是面板中的元素相当大。我附上结果:

这是我的代码:

public static void delete()
{
    int deletePosition;
    String[] options = {"Confirm", "Cancel"};
    JPanel panel = new JPanel();

    JLabel label0 = new JLabel("Write the Position[#]:");
    JLabel labelJump1 = new JLabel("");
    JTextField txtDelete = new JTextField(1);
    GridLayout gridLayout = new GridLayout(0,1);
    panel.setLayout(gridLayout);

    String fullText = "";
    JTextArea textArea = new JTextArea(15,30);
        textArea.setText(fullText);
        textArea.setEditable(false);
    JScrollPane scrollPane = new JScrollPane(textArea);

    panel.add(scrollPane);
    panel.add(label0);
    panel.add(labelJump1);
    panel.add(txtDelete);

    try
    {
        if (theEntityCollection.checkEmpty())
            JOptionPane.showMessageDialog(null, "The collection is EMPTY");
        else
        {
            for(int i = 0 ; i < theEntityCollection.getArraySize() ; i++)
            {

                fullText += "Position [" + (i+1) + "]\n\n" + theEntityCollection.getEntity(i);
                    if (i != theEntityCollection.getArraySize() - 1)
                        fullText += "_____________________\n\n"; 
                textArea.setText(fullText);
            }
            deletePosition = JOptionPane.showOptionDialog(null, panel, "ENTITY COLLECTION", JOptionPane.NO_OPTION, JOptionPane.PLAIN_MESSAGE, null, options , options[0]);
        }
    }
    catch(Exception e)
    {
        System.out.println("FAILED");
    }
    fullText = "";
}

我必须说我是 Java GUI 的新手。

如果您能帮助我，我将不胜感激!

Answer 1

GridLayout 正在执行其设计目的。它为每个组件提供完全相同的空间量，根据可用空间均匀分布。您可能需要使用更灵活的布局管理器，例如......

从改变开始...

GridLayout gridLayout = new GridLayout(0,1);
panel.setLayout(gridLayout);

类似...

GridBagLayout gridLayout = new GridBagLayout();
panel.setLayout(gridLayout);
GridBagConstraints gbc = new GridBagConstraints();
gbc.weightx = 1;
gbc.anchor = GridBagConstraints.WEST;
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.insets = new Insets(2, 2, 2, 2);

然后改变...

panel.add(scrollPane);
panel.add(label0);
panel.add(labelJump1);
panel.add(txtDelete);

更像是......

panel.add(scrollPane, gbc);
panel.add(label0, gbc);
panel.add(labelJump1, gbc);
panel.add(txtDelete, gbc);

看看Laying Out Components Within a Container和 How to Use GridBagLayout了解更多详情