如何为窗口应用程序设置setBorder? [英] How to setting setBorder for window application?

问题描述

我尝试创建一些用于监视网络的应用程序.我将创建4个JPanels并插入例如insert_panel_0，insert_panel_2到panel_2的面板.我无法在insert_panel_0，insert_panel_2之间设置边框.我有垂直缝隙，但没有水平缝隙.

I tried create some application for monitoring network. I'm going to create 4 JPanels and insert, for example, panels insert_panel_0, insert_panel_2 to panel_2.I can't setting my borders between insert_panel_0, insert_panel_2. I have vertical gaps, but i don't have horizontal gaps.

您能帮我解决吗?

import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.Toolkit;

import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;

public class setting {

    public static void main(String[] args) {

        //get size window
        Dimension tk = Toolkit.getDefaultToolkit().getScreenSize();

        int  width = (int) tk.width;
        int  hight = (int) tk.height;



        JFrame frame = new JFrame(); 
        frame.setLayout(new GridLayout(1,4, 0, 0));
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().setBackground(Color.black);
        frame.setExtendedState(JFrame.MAXIMIZED_BOTH); 



        // set panels for window
        JPanel panel_0 = new JPanel();
        panel_0.setLayout(new FlowLayout(FlowLayout.CENTER, 0, 0));
        panel_0.setBorder(new EmptyBorder(20, 20,20, 20));
        panel_0.setBackground(Color.white);
        frame.add(panel_0);



        JPanel panel_1 = new JPanel();
        panel_1.setLayout(new FlowLayout(FlowLayout.CENTER, 0, 0));
        panel_1.setBackground(Color.yellow);
        panel_1.setBorder(new EmptyBorder(20, 20,20, 20));      
        frame.add(panel_1);

        JPanel panel_2 = new JPanel();
        panel_2.setLayout(new FlowLayout(FlowLayout.CENTER, 0, 0));
        panel_2.setBorder(new EmptyBorder(20, 20,20, 20));      
        panel_2.setBackground(Color.green);
        frame.add(panel_2);


        JPanel panel_3 = new JPanel();
        panel_3.setLayout(new FlowLayout(FlowLayout.CENTER, 0, 0));
        panel_3.setBorder(new EmptyBorder(20, 20,20, 20));      
        panel_3.setBackground(Color.blue);

        frame.add(panel_3);

        JPanel insert_panel_0 = new JPanel();
        insert_panel_0.setPreferredSize( new Dimension(width/4, (int) Math.round( hight*0.05)));
        insert_panel_0.setBackground(Color.black);
        panel_2.add(insert_panel_0);

        JPanel insert_panel_1 = new JPanel();
        insert_panel_1.setPreferredSize( new Dimension(width/4, (int) Math.round( hight*0.05)));
        insert_panel_1.setBackground(Color.black);
        panel_2.add(insert_panel_1);    

        frame.setVisible(true);
    }

}

推荐答案

insert_panel_0.setPreferredSize( new Dimension(width/4, (int) Math.round( hight*0.05)));

问题是您的宽度计算.当您将其除以4时，每个黑色子面板的宽度就是整个父面板的宽度.这会导致两个问题:

The problem is your width calculation. When you divide by 4 the width of each black child panel is the width of the entire parent panel. This causes two problems:

1. 子面板无法与20像素边框的父面板配合，因此它会在面板边缘绘制
2. 然后，FlowLayout将自动将第二个面板包装到下一行.因此面板显示在两行上.

解决方案是改善宽度计算，例如:

The solution is to improve your width calculation for example:

insert_panel_0.setPreferredSize( new Dimension(width/12, (int) Math.round( hight*0.05)));

现在，两个面板将出现在同一行中.

Now the two panels will appear on the same row.

如果要在两个黑色面板之间留出空隙，则还需要:

If you want a gap between the two black panels then you also need:

//panel_2.setLayout(new FlowLayout(FlowLayout.CENTER, 0, 0));
panel_2.setLayout(new FlowLayout(FlowLayout.CENTER, 20, 0));

这篇关于如何为窗口应用程序设置setBorder?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！