对两个元素使用 GridBagConstraints.anchor = NORTH答案

【问题标题】：Using GridBagConstraint.anchor = NORTH for two elements对两个元素使用 GridBagConstraints.anchor = NORTH
【发布时间】：2013-04-11 13:24:20
【问题描述】：

我想将 GridBagLayout 中的两个元素设置在彼此之上，并且两者都应位于布局的顶部（第二个元素应从第一个元素的底部开始）。

此外，第二个元素应将空间向下填充到底部。

gbc.anchor = GridBagConstraint.NORTH 适用于第一个元素，但第二个元素不会粘在可用空间的顶部。相反，它会停留在布局后半部分的顶部。

这是我的代码：

import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;

import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;


public class TestFrame extends JFrame{

    public TestFrame(){
        this.setDefaultCloseOperation(EXIT_ON_CLOSE);

        this.setLayout(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();

        gbc.anchor = GridBagConstraints.NORTH;
        gbc.weighty = 1.0;

        JPanel one = new JPanel();
        one.setPreferredSize(new Dimension(200,200));
        one.setBorder(BorderFactory.createLineBorder(Color.BLACK));

        JPanel two = new JPanel();
        two.setPreferredSize(new Dimension(200,200));
        two.setBorder(BorderFactory.createLineBorder(Color.BLACK));

        this.add(one, gbc);

        gbc.gridy = 1;
        gbc.fill = GridBagConstraints.VERTICAL;

        this.add(two, gbc);

        this.pack();
        this.setVisible(true);
    }

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

【问题讨论】：

标签： java swing gridbaglayout

【解决方案1】：

我刚刚找到了一个解决方案：如果我将第一个元素的wheighty 设置为0.0，并且仅将第二个元素的weighty 设置为1.0，它将按计划工作。

import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;

import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;


public class TestFrame extends JFrame{

    public TestFrame(){
        this.setDefaultCloseOperation(EXIT_ON_CLOSE);

        this.setLayout(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();

        gbc.anchor = GridBagConstraints.NORTH;
        gbc.weighty = 0.0;

        JPanel one = new JPanel();
        one.setPreferredSize(new Dimension(200,200));
        one.setBorder(BorderFactory.createLineBorder(Color.BLACK));

        JPanel two = new JPanel();
        two.setPreferredSize(new Dimension(200,200));
        two.setBorder(BorderFactory.createLineBorder(Color.BLACK));

        this.add(one, gbc);

        gbc.gridy = 1;
        gbc.weighty = 0.0;
        gbc.fill = GridBagConstraints.VERTICAL;

        this.add(two, gbc);

        this.pack();
        this.setVisible(true);
    }

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

【讨论】：