如何巧妙的运用好弹簧布局SpringLayout？

矫情吗；* 2023-10-03 10:41 22阅读 0赞

### 弹簧布局SpringLayout ###

package Test;
    //弹簧布局SpringLayout
    //就是先定位好一个组件，其他组件都可以参照已经定位好的组件来定位即可
    import javax.swing.*;
    import java.awt.*;
    
    public class SpringLayoutTest extends JFrame {
        
    
        //设置jpanel的布局管理器为springlayout
        SpringLayout springLayout=new SpringLayout();
        JPanel jPanel=new JPanel(springLayout);
    
        JLabel titleLable=new JLabel("文章标题:");
        JTextField titleTxt=new JTextField();
    
        JLabel authorLable =new JLabel("作者:");
        JTextField authorTxt=new JTextField();
    
        JLabel contLable=new JLabel("请输入内容:");
        JTextArea contArea= new JTextArea(4,10);
    
        //创建构造函数
        public  SpringLayoutTest(){
        
            super("弹簧布局springLayout");
            Container contentPane =getContentPane();
            //加入到jpanel中
            titleTxt.setPreferredSize(new Dimension(200,30));
    
            jPanel.add(titleLable);
            jPanel.add(titleTxt);
            jPanel.add(authorLable);
            authorTxt.setPreferredSize(new Dimension(200,30));
            jPanel.add(authorTxt);
            jPanel.add(contLable);
            jPanel.add(contArea);
            jPanel.setBackground(Color.yellow);
    
            /*
            SpringLayout:布局管理器
            SpringLayout.Constraints:使用弹簧布局的容器里面的组件的布局约束，每个组件对于一个
            Spring:可以理解为一个可以进行四则运算的整数
             */
    
            //设置水平居中
            Spring titleLableWidth=Spring.width(titleLable);
            Spring titleTxtWidt=Spring.width(titleTxt);
            Spring spaceWidth=Spring.constant(20);  //其间距为20
            Spring childWidth = Spring.sum(Spring.sum(titleLableWidth,titleTxtWidt),spaceWidth);
            int offsetX=childWidth.getValue()/2;
    
            SpringLayout.Constraints titleLableC = springLayout.getConstraints(titleLable);
    //        titleLableC.setX(Spring.constant(100));
            springLayout.putConstraint(SpringLayout.WEST,titleLable,-offsetX,SpringLayout.HORIZONTAL_CENTER,jPanel);
            titleLableC.setY(Spring.constant(50));
            //这是标题文本框：titleTxt西边距离titleLable的东边20px，北边相同
            SpringLayout.Constraints titleTxtC = springLayout.getConstraints(titleTxt);
            //edgeName：东南西北  s:表示值
            Spring titleLableEastSpring= titleLableC.getConstraint(SpringLayout.EAST);
           titleTxtC.setConstraint(SpringLayout.WEST,Spring.sum(titleLableEastSpring,Spring.constant(20)));
           titleTxtC.setConstraint(SpringLayout.NORTH,titleLableC.getConstraint(SpringLayout.NORTH));
    
           /*
           设置约束的第二种写法，相对简单
           e1:要设置组件的哪个边界（edgeName）
           c1:要设置的组件
           pad：距离值
           e2：参照的组件的边界名
           c2：参照物（组件）
            *///设置作者Lable  authorLable：东边和titleLable对齐，北边距离titleLable南边20px
           springLayout.putConstraint(SpringLayout.EAST,authorLable,0,SpringLayout.EAST,titleLable);
           springLayout.putConstraint(SpringLayout.NORTH,authorLable,40,SpringLayout.NORTH,titleLable);
    
           //设置authorTxt：authorTxt西边  距离 authorLable的东边20px，北边和authorLable相同
            springLayout.putConstraint(SpringLayout.WEST,authorTxt,20,SpringLayout.EAST,authorLable);
            springLayout.putConstraint(SpringLayout.NORTH,authorTxt,0,SpringLayout.NORTH,authorLable);
    
            //内容contLable
            springLayout.putConstraint(SpringLayout.EAST,contLable,0,SpringLayout.EAST,authorLable);
            springLayout.putConstraint(SpringLayout.NORTH,contLable,40,SpringLayout.NORTH,authorLable);
    
            //contArea
            springLayout.putConstraint(SpringLayout.WEST,contArea,20,SpringLayout.EAST,contLable);
            springLayout.putConstraint(SpringLayout.NORTH,contArea,0,SpringLayout.NORTH,contLable);
    
            //contArea的南边和东边参照jpanel
            springLayout.putConstraint(SpringLayout.SOUTH,contArea,-20,SpringLayout.SOUTH,jPanel);
            springLayout.putConstraint(SpringLayout.EAST,contArea,-20,SpringLayout.EAST,jPanel);
    
            contentPane.add(jPanel);
    
            setSize(600,400); //窗口大小
            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  //关闭退出程序
            setVisible(true);//窗口可视化
    
        }
        public static void main(String[] args) {
        
            new SpringLayoutTest();
        }
    
    
    }