java - 开始 GridBagLayout

Question

我的问题是当我不乱用 ipadx 和 ipady 时。我的按钮粘在一起，但当我摆弄 ipadx 和 ipady 时，我发现第三个按钮将一个单元格移开。为什么以及如何解决这个困惑？代码:

public class Testagain extends JFrame {

    private JPanel pan1;
    private JPanel pan2;
    private JPanel pan3;


    private JButton btn1;
    private JButton btn2;
    private JButton btn3;


    public Testagain()
    {
        super("Panel TEST GRID");
        super.setSize(500, 500);

        btn1 = new JButton(" 1");
        pan1 = new JPanel(new GridBagLayout());
        GridBagConstraints con1 = new GridBagConstraints();
        con1.gridx = 0;
        con1.gridy = 0;
        con1.ipadx = 80;
        con1.ipady = 60;
        pan1.add(btn1,con1);

        btn2 = new JButton("2");
        pan2 = new JPanel(new GridBagLayout());
        GridBagConstraints con2 = new GridBagConstraints();
        con2.ipady = 60;
        con2.ipadx = 0;
        con2.gridx = 1;
        con2.gridy = 0;
        pan1.add(btn2,con2);



        btn3 = new JButton("3");
        pan3 = new JPanel(new GridBagLayout());
        GridBagConstraints con3 = new GridBagConstraints();
        con3.ipady = 60;
        con3.ipadx = 0;
        con3.gridx = 2;
        con3.gridy = 0;


        pan3.add(btn3,con3);


        Container tain = super.getContentPane();
        tain.setLayout(new GridBagLayout());

        tain.add(pan1,con1);
        tain.add(pan2,con2);
        tain.add(pan3,con3);






        super.setVisible(true);
        super.setDefaultCloseOperation(EXIT_ON_CLOSE);
    }

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

}

Answer 1

您将 btn1 和 btn2 添加到 pan1 中，因此 pan2 被赋予了它自己的单元格...

btn1 = new JButton(" 1");
pan1 = new JPanel(new GridBagLayout());
//...
pan1.add(btn1,con1);

btn2 = new JButton("2");
pan2 = new JPanel(new GridBagLayout());
//...
pan1.add(btn2,con2);

所以，我稍微研究了一下你的代码，消除了一些困扰我的复杂性，并能够生成预期的输出

import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import static javax.swing.JFrame.EXIT_ON_CLOSE;
import javax.swing.JPanel;

public class Testagain extends JFrame {

    private JPanel pan1;
    private JPanel pan2;
    private JPanel pan3;

    private JButton btn1;
    private JButton btn2;
    private JButton btn3;

    public Testagain() {
        super("Panel TEST GRID");
        super.setSize(500, 500);

        GridBagConstraints con1 = new GridBagConstraints();
        btn1 = new JButton(" 1");
        btn2 = new JButton("2");
        btn3 = new JButton("3");

        Container tain = super.getContentPane();
        tain.setLayout(new GridBagLayout());

        con1.gridx = 0;
        con1.gridy = 0;
        con1.ipadx = 80;
        con1.ipady = 60;
        tain.add(btn1, con1);
        con1.ipadx = 0;
        con1.gridx = 1;
        con1.gridx = 60;
        tain.add(btn2, con1);
        con1.gridx = 2;
        tain.add(btn3, con1);

        super.setVisible(true);
        super.setDefaultCloseOperation(EXIT_ON_CLOSE);
    }

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

我不知道为什么你使用中间面板来简单地添加一个按钮，但由于按钮和面板使用相同的约束，这对我来说似乎有些“奇怪”，但这可能是一个更大的快照，我不知道