Question

我有3个JPanels，我想将它们全部放在一个JPanel中。我使用GridBagLayout作为主面板。但是只添加了一个面板。为什么会这样？

    gblayout=new GridBagLayout();
    gbc=new GridBagConstraints();
    panel1Customizer();
    panel2customizer();
    panel3Customizer();
    setLayout(gblayout);
    gbc.fill=GridBagConstraints.HORIZONTAL;
    gbc.anchor=GridBagConstraints.NORTHWEST;
    gbc.weightx=1;
    gbc.weighty=1;
    gbc.gridheight=GridBagConstraints.REMAINDER;
    add(panel1, gbc);
    add(panel2, gbc);
    gbc.gridwidth=GridBagConstraints.REMAINDER;
    add(panel3, gbc);

自定义程序方法是将项目添加到这些面板中的方法。

Answer 1

我不确定，但我认为您需要在GridBagLayout中添加GridBagConstraints。试试看这个网站，了解如何使用GridBagLayout： link

或者也许只是为你的JFrame使用另一个布局，可能是BorderLayout或GridLayout来正确排列你的面板

Answer 2

您应该为每个面板更改gbc.gridx和/或gbc.gridy

Answer 3

您必须阅读How to Use GridBagLayout，here和GridBagConstraints的示例，如果您遇到gbc.fill=GridBagConstraints.HORIZONTAL;问题，请更改JComponent's Size添加setPreferedSize();例如

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.*;

public class GBLFillBoth extends JFrame {
    private static final long serialVersionUID = 1L;

  public GBLFillBoth() {
    JPanel panel = new JPanel();
    GridBagLayout gbag = new GridBagLayout();
    panel.setLayout(gbag);
    GridBagConstraints c = new GridBagConstraints();
    JButton btn1 = new JButton("One");
    c.fill = GridBagConstraints.BOTH;
    //c.fill = GridBagConstraints.HORIZONTAL;
    c.anchor=GridBagConstraints.NORTHWEST;
    c.gridx = 0;
    c.gridy = 0;
    c.weightx = 0.5;
    c.weighty = 0.5;
    panel.add(btn1, c);
    JButton btn2 = new JButton("Two");
    c.gridx++;
    panel.add(btn2, c);
    //c.fill = GridBagConstraints.BOTH;
    JButton btn3 = new JButton("Three");
    c.gridx = 0;
    c.gridy++;
    c.gridwidth = 2;
    panel.add(btn3, c);
    add(panel);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    pack();
    setVisible(true);
  }

  public static void main(String[] args) {
        GBLFillBoth gBLFillBoth = new GBLFillBoth();
  }
}

Answer 4

您可以考虑使用MigLayout，代码更简单：

panel1Customizer();
panel2customizer();
panel3Customizer();
setLayout(new MigLayout("fill, wrap 3"));

add(panel1, "grow");
add(panel2, "grow");
add(panel3, "grow");

无法将3个JPanel添加到主面板

4 个答案: