learning java AWT 布局管理器 GridBagLayout

在GridBagLayout布局管理器中，一个组件可以跨越一个或多个网格，并可以设置各网格的大小互不相关。

import java.awt.*;

public class GridBagTest {

    private Frame f =  new Frame("测试窗口");

    private GridBagLayout gb = new GridBagLayout();

    private GridBagConstraints  gbc = new GridBagConstraints();

    private Button[] bs = new Button[10];

    public void init(){

        f.setLayout(gb);

        for (var i = 0; i < 10; i++){

            bs[i] = new Button("button" + i);

        }

        gbc.fill = GridBagConstraints.BOTH;

        gbc.weightx = 1;

        addButton(bs[0]);

        addButton(bs[1]);

        addButton(bs[2]);

        gbc.gridwidth = GridBagConstraints.REMAINDER;

        addButton(bs[3]);

        //横向不会扩展

        gbc.weightx = 0;

        addButton(bs[4]);

        //宽度占两格,高度占一格

        gbc.gridwidth = 2;

        gbc.gridheight = 1;

        addButton(bs[5]);

        //宽度占两格,高度占一格

        //gbc.gridwidth = 2;

        //gbc.gridheight = 1;

        gbc.gridwidth = GridBagConstraints.REMAINDER;

        addButton(bs[6]);

        // 另起一行，宽度占一格，高度占两格。

        gbc.gridwidth =1;

        gbc.gridheight =2;

        addButton(bs[7]);

        // 纵向不再扩展，高度占一格，结束

        gbc.weighty = 0;

        gbc.gridwidth =GridBagConstraints.REMAINDER;

        gbc.gridheight = 1;

        addButton(bs[8]);

        addButton(bs[9]);

        f.pack();

        f.setVisible(true);

    }

    private void addButton(Button button){

        gb.setConstraints(button, gbc);

        f.add(button);

    }

    public static void main(String[] args) {

        new GridBagTest().init();

    }

}

　output: