Java Swing：管理多个SpringLayout

Question

我想管理一个复杂结构的容器作为 SpringLayouts 的组合（一系列独立的 SpringLayout 一个在另一个里面）

特别是，由包含 JPanel 的主 SpringLayout 管理的 JFrame：每个 JPanel 都应由其自己的 SpringLayout 管理。

不幸的是，如果我尝试应用两个不同的 SpringLayout，框架上什么也没有出现

我编写了这个简单的代码来向您展示问题所在。代码包含：

JFrame 及其 SprilgLayout
一个 JPanel 及其 SpringLayout
JPanel 中的一个简单的 JButton

这里是代码：

import java.awt.Container;
import java.awt.Dimension;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SpringLayout;

public class SpringLayout_cobination {

    // THE OBJECTS
    static JFrame frame;// The frame
    static JPanel panel;        // The container
    static JButton Button;      // Object

    // THE LayOuts
    static SpringLayout LayOut_Frame;
    static SpringLayout LayOut_panel;
    static Container contentPane;

    public static void main(String[] args) {

        // Start frame and componets
        frame=new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        frame.setSize(830, 420); 

        panel=new JPanel();
        Button=new JButton("ok");

        panel.add(Button);
        panel.setSize(new Dimension(100,100));
        frame.add(panel);

        // Set the layouts
        LayOut_Frame=new SpringLayout(); // Frame LayOut
        frame.setLayout(LayOut_Frame);
        contentPane=frame.getContentPane(); // Main Container of the frame

        LayOut_panel=new SpringLayout();
        panel.setLayout(LayOut_panel);

        LayOut_Frame.putConstraint(SpringLayout.NORTH, panel,30,SpringLayout.NORTH, contentPane);
        LayOut_Frame.putConstraint(SpringLayout.WEST, panel,30,SpringLayout.WEST , contentPane);

        LayOut_panel.putConstraint(SpringLayout.NORTH, contentPane,30,SpringLayout.NORTH, Button);
        LayOut_panel.putConstraint(SpringLayout.WEST, contentPane,30,SpringLayout.WEST , Button);

        frame.setVisible(true);
    }

}

Answer 1

apply two different SpringLayout

如果我了解您的要求，我认为可以将 SpringLayout 组合如下：

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

public class SpringLayoutCobinationTest {
  private static Component makeSubPanel() {
    JButton button = new JButton("ok");

    SpringLayout layout = new SpringLayout();
    JPanel pnl = new JPanel(layout);

    layout.putConstraint(SpringLayout.NORTH, button, 10, SpringLayout.NORTH, pnl);
    layout.putConstraint(SpringLayout.WEST, button, 10, SpringLayout.WEST, pnl);

    pnl.add(button);
    pnl.setBorder(BorderFactory.createLineBorder(Color.RED));

    return pnl;
  }
  public Component makeUI() {
    Component sub = makeSubPanel();

    SpringLayout layout = new SpringLayout();
    SpringLayout.Constraints c = layout.getConstraints(sub);
    c.setWidth(Spring.constant(100));
    c.setHeight(Spring.constant(100));

    JPanel panel = new JPanel(layout);
    layout.putConstraint(SpringLayout.NORTH, sub, 30, SpringLayout.NORTH, panel);
    layout.putConstraint(SpringLayout.WEST, sub, 30, SpringLayout.WEST, panel);
    panel.add(sub);

    return panel;
  }
  public static void main(String[] args) {
    EventQueue.invokeLater(() -> {
      JFrame f = new JFrame();
      f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      f.add(new SpringLayoutCobinationTest().makeUI());
      f.setSize(420, 420);
      f.setLocationRelativeTo(null);
      f.setVisible(true);
    });
  }
}

Answer 2

我忘记的部分代码是：

SpringLayout.Constraints c = LayOut_Frame.getConstraints(panel);
c.setWidth(Spring.constant(200));
c.setHeight(Spring.constant(100));

似乎每次在主框架中导入组件时都必须施加一个Constraints维度

在我的示例中，当我导入最终代码为：

import java.awt.Container;
import java.awt.Dimension;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Spring;
import javax.swing.SpringLayout;

public class SpringLayout_cobination {

    // THE OBJECTS
    static JFrame frame;// The frame
    static JPanel panel;        // The container
    static JButton Button;      // Object

    // THE LayOuts
    static SpringLayout LayOut_Frame;
    static SpringLayout LayOut_panel;
    static Container contentPane;

    public static void main(String[] args) {

        // Start frame and componets
        frame=new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        frame.setSize(830, 420); 

        panel=new JPanel();
        Button=new JButton("ok");

        panel.add(Button);
        panel.setSize(new Dimension(100,100));
        frame.add(panel);

        // Set the layouts
        LayOut_Frame=new SpringLayout(); // Frame LayOut
        frame.setLayout(LayOut_Frame);
        contentPane=frame.getContentPane(); // Main Container of the frame

        LayOut_panel=new SpringLayout();
        panel.setLayout(LayOut_panel);
        LayOut_panel.putConstraint(SpringLayout.NORTH, contentPane,30,SpringLayout.NORTH, Button);
        LayOut_panel.putConstraint(SpringLayout.WEST, contentPane,30,SpringLayout.WEST , Button);

        SpringLayout.Constraints c = LayOut_Frame.getConstraints(panel);
        c.setWidth(Spring.constant(200));
        c.setHeight(Spring.constant(100));

        LayOut_Frame.putConstraint(SpringLayout.NORTH, panel,30,SpringLayout.NORTH, contentPane);
        LayOut_Frame.putConstraint(SpringLayout.WEST, panel,30,SpringLayout.WEST , contentPane);



        frame.setVisible(true);
    }

}

Java Swing：管理多个SpringLayout

Java Swing: manage multiple SpringLayout

java

layout

swing

layout-manager

springlayout