java 实现自定义框架

简介

实现LayoutManager 接口即可，只要实现5个接口杰克

分别是

void addLayoutComponent(String s, Component c);

void removeLayoutComponent(Component c);

Dimension perferredLayoutSize(Container parent);

Dimension minimumLayoutSize(Container parent);

void layoutContainer(Container parent);

java 核心编程带来了 如下的circleLayout

code

/*
 * @Author: your name
 * @Date: 2020-11-08 13:51:10
 * @LastEditTime: 2020-11-08 13:54:40
 * @LastEditors: your name
 * @Description: In User Settings Edit
 * @FilePath: /java/circleLayout/CircleLayout.java
 */
package circleLayout;

import java.awt.*;

/**
 * A layout manager that lays out components along a circle.
 */
public class CircleLayout implements LayoutManager {
   private int minWidth = 0;
   private int minHeight = 0;
   private int preferredWidth = 0;
   private int preferredHeight = 0;
   private boolean sizesSet = false;
   private int maxComponentWidth = 0;
   private int maxComponentHeight = 0;

   public void addLayoutComponent(String name, Component comp) {
   }

   public void removeLayoutComponent(Component comp) {
   }

   public void setSizes(Container parent) {
      if (sizesSet)
         return;
      int n = parent.getComponentCount();

      preferredWidth = 0;
      preferredHeight = 0;
      minWidth = 0;
      minHeight = 0;
      maxComponentWidth = 0;
      maxComponentHeight = 0;

      // compute the maximum component widths and heights
      // and set the preferred size to the sum of the component sizes
      for (int i = 0; i < n; i++) {
         Component c = parent.getComponent(i);
         if (c.isVisible()) {
            Dimension d = c.getPreferredSize();
            maxComponentWidth = Math.max(maxComponentWidth, d.width);
            maxComponentHeight = Math.max(maxComponentHeight, d.height);
            preferredWidth += d.width;
            preferredHeight += d.height;
         }
      }
      minWidth = preferredWidth / 2;
      minHeight = preferredHeight / 2;
      sizesSet = true;
   }

   public Dimension preferredLayoutSize(Container parent) {
      setSizes(parent);
      Insets insets = parent.getInsets();
      int width = preferredWidth + insets.left + insets.right;
      int height = preferredHeight + insets.top + insets.bottom;
      return new Dimension(width, height);
   }

   public Dimension minimumLayoutSize(Container parent) {
      setSizes(parent);
      Insets insets = parent.getInsets();
      int width = minWidth + insets.left + insets.right;
      int height = minHeight + insets.top + insets.bottom;
      return new Dimension(width, height);
   }

   public void layoutContainer(Container parent) {
      setSizes(parent);

      // compute center of the circle

      Insets insets = parent.getInsets();
      int containerWidth = parent.getSize().width - insets.left - insets.right;
      int containerHeight = parent.getSize().height - insets.top - insets.bottom;

      int xcenter = insets.left + containerWidth / 2;
      int ycenter = insets.top + containerHeight / 2;

      // compute radius of the circle

      int xradius = (containerWidth - maxComponentWidth) / 2;
      int yradius = (containerHeight - maxComponentHeight) / 2;
      int radius = Math.min(xradius, yradius);

      // lay out components along the circle

      int n = parent.getComponentCount();
      for (int i = 0; i < n; i++) {
         Component c = parent.getComponent(i);
         if (c.isVisible()) {
            double angle = 2 * Math.PI * i / n;

            // center point of component
            int x = xcenter + (int) (Math.cos(angle) * radius);
            int y = ycenter + (int) (Math.sin(angle) * radius);

            // move component so that its center is (x, y)
            // and its size is its preferred size
            Dimension d = c.getPreferredSize();
            c.setBounds(x - d.width / 2, y - d.height / 2, d.width, d.height);
         }
      }
   }
}

/*
 * @Author: your name
 * @Date: 2020-11-08 13:51:10
 * @LastEditTime: 2020-11-08 13:51:37
 * @LastEditors: your name
 * @Description: In User Settings Edit
 * @FilePath: /java/circleLayout/CircleLayoutFrame.java
 */
package circleLayout;

import javax.swing.*;

/**
 * A frame that shows buttons arranged along a circle.
 */
public class CircleLayoutFrame extends JFrame {
   public CircleLayoutFrame() {
      setLayout(new CircleLayout());
      add(new JButton("Yellow"));
      add(new JButton("Blue"));
      add(new JButton("Red"));
      add(new JButton("Green"));
      add(new JButton("Orange"));
      add(new JButton("Fuchsia"));
      add(new JButton("Indigo"));
      pack();
   }
}

package circleLayout;

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

/**
 * @version 1.34 2018-04-10
 * @author Cay Horstmann
 */
public class CircleLayoutTest {
   public static void main(String[] args) {
      EventQueue.invokeLater(() -> {
         var frame = new CircleLayoutFrame();
         frame.setTitle("CircleLayoutTest");
         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
         frame.setVisible(true);
      });
   }
}