Summary of Java layout manager

FlowLayout

explain

This layout manager is a flow layout manager, which will make all components arranged like a flow, from left to right and from top to bottom. If the arrangement fails, it will wrap lines. If the window is opened, it will continue to be arranged like a flow.

Common methods and constants

Serial number	Methods and constants	type	describe
1	public static final int CENTER	constant	Center alignment
2	public static final int LEADING	constant	Same as the beginning of the container
3	public static final int LEFT	constant	Align left
4	public static final int RIGHT	constant	Right align
5	public static final int TRAILING	constant	Same as the end of the container
6	public FlowLayout()	structure	Construct a new FlowLayout, align it in the center, and the default horizontal and vertical spacing is 5 units
7	public FlowLayout(int align)__	structure	Construct a FlowLayout and specify the alignment
8	public FlowLayout(int align.int bgap,int vgap)	structure	Specify alignment, horizontal, vertical spacing

Code example

package com.learnspringboot.libra;

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

/**
 * FlowLayoutTest01 class
 * Date: November 22, 2021
 * Time: 12:42
 *
 * @author Don't bully Xiaobai, okay
 */
public class FlowLayoutTest01 {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Welcome!");
        // The last two parameters, hgap and vgap, set the gap between components.
        frame.setLayout(new FlowLayout(FlowLayout.CENTER,3,3));
        JButton but = null;
        int end = 9;
        for (int i = 0; i < end; i++) {
            but = new JButton("Button --> " + i);
            frame.add(but);
        }

        Toolkit tk = Toolkit.getDefaultToolkit();
        Dimension size = tk.getScreenSize();
        // Sets the size of the window
        int FrameWidth = 350;
        int FrameHeight = 130;
        // Set the position of the window. This calculation will make it in the center of the screen
        int screenHeight = size.height / 2 - FrameHeight / 2;
        int screenWidth = size.width / 2 - FrameWidth / 2;

        // Sets the position of the window
        frame.setLocation(screenWidth,screenHeight);
        frame.setSize(FrameWidth,FrameHeight);
        // Add an event listener, which means that the program exits when the window is closed, so you don't have to exit the program every time the window is closed.
        frame.addWindowListener(new MyWindowListener());
        frame.setVisible(true);
    }
}

Operation results

BorderLayout

Common methods and constants

Serial number	Methods and constants	type	Description
1	public static final String EAST	constant	Set component in East region
2	public static final String WEST	constant	Set component in West Region
3	public static final String SOUTH	constant	Set the component in the south area
4	public static final String NORTH	constant	Set component in North Region
5	public static final String CENTER	constant	Set components in area
6	public Border ayout()	structure	Construct a layout without distance
7	public BorderLayout(int hgap，int vgap)	structure	Construct a layout with horizontal and vertical spacing

explain

The layout manager will divide a form into five parts, namely, East, West, North and south. All components will be placed in these five areas. You can directly set which area to put in. If you don't specify it, it will be placed in the middle area by default.

Code example

package com.learnspringboot.libra;

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

/**
 * BorderLayoutTest01 class
 * Date: November 22, 2021
 * Time: 13:21
 *
 * @author Don't bully Xiaobai, okay
 */
public class BorderLayoutTest01 {

    public BorderLayoutTest01(String title){
        JFrame frame = new JFrame(title);
        frame.setLayout(new BorderLayout(3,3));
        frame.add(new JButton("East( EAST)"),BorderLayout.EAST);
        frame.add(new JButton("West( WEST)"),BorderLayout.WEST);
        frame.add(new JButton("South( SOUTH)"),BorderLayout.SOUTH);
        frame.add(new JButton("North( NORTH)"),BorderLayout.NORTH);
        frame.add(new JButton("Medium( CENTER)"),BorderLayout.CENTER);

        Toolkit tk = Toolkit.getDefaultToolkit();
        Dimension size = tk.getScreenSize();
        // Sets the size of the window
        int FrameWidth = 350;
        int FrameHeight = 130;
        // Set the position of the window. This calculation will make it in the center of the screen
        int screenHeight = size.height / 2 - FrameHeight / 2;
        int screenWidth = size.width / 2 - FrameWidth / 2;

        // Sets the position of the window
        frame.setLocation(screenWidth,screenHeight);
        frame.setSize(FrameWidth,FrameHeight);
        // Sets the position of the window
        frame.setLocation(screenWidth,screenHeight);
        frame.setSize(FrameWidth,FrameHeight);
        frame.addWindowListener(new MyWindowListener());
        frame.setVisible(true);
    }

    public BorderLayoutTest01(){
        this("Hello World!");
    }

}

Operation results

GridLayout

Common methods and constants

Serial number	method	type	Description
1	public GridLayout(int rows,int cols)	structure	Construct a layout manager that specifies rows and columns
2	public GridLayout(int rows,int cols,int hgap,int vgap)	structure	Specify row and column, horizontal and vertical spacing when constructing

explain

The layout manager is a table manager. It is a table that divides the window into specific rows and columns, and then each component occupies a small grid in it.

Code example

package com.learnspringboot.libra;

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

/**
 * GridLayoutTest01 class
 * Date: November 22, 2021
 * Time: 13:50
 *
 * @author Don't bully Xiaobai, okay
 */
public class GridLayoutTest01 {
    public GridLayoutTest01(String title){
        JFrame frame = new JFrame(title);
        frame.setLayout(new GridLayout(3,5,3,3));
        JButton but = null;
        int end = 15;
        for (int i = 0; i < end; i++) {
            but = new JButton("Button --> " + i);
            frame.add(but);
        }
        Toolkit tk = Toolkit.getDefaultToolkit();
        Dimension size = tk.getScreenSize();

        int FrameWidth = 600;
        int FrameHeight = 200;

        int screenHeight = size.height / 2 - FrameHeight / 2;
        int screenWidth = size.width / 2 - FrameWidth / 2;

        frame.setLocation(screenWidth,screenHeight);
        frame.setSize(FrameWidth,FrameHeight);
        frame.addWindowListener(new MyWindowListener());
        frame.setVisible(true);
    }

    public GridLayoutTest01(){
        this("Welcome!");
    }


}

Operation results

Calculator instance

Made a calculator window

The following is the source code

package com.learnspringboot.libra.calculator;

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

/**
 * SetFrame class
 * Date: November 24, 2021
 * Time: 19:27
 *
 * @author Don't bully Xiaobai, okay
 */
public class SetFrame {
    public SetFrame(JFrame frame,int FrameWidth,int FrameHeight){
        Toolkit tk = Toolkit.getDefaultToolkit();
        Dimension size = tk.getScreenSize();
        int screenHeight = size.height / 2 - FrameHeight / 2;
        int screenWidth = size.width / 2 - FrameWidth / 2;
        frame.setLocation(screenWidth,screenHeight);
        frame.setSize(FrameWidth,FrameHeight);

    }
}

package com.learnspringboot.libra.calculator;

/**
 * Application class
 * Date: November 22, 2021
 * Time: 13:21
 *
 * @author Don't bully Xiaobai, okay
 */
public class Application {
    public static void main(String[] args) {
        new MyFrameDraw();
    }
}

package com.learnspringboot.libra.calculator;

import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;

/**
 * MyWindowListener class
 * Date: November 22, 2021
 * Time: 12:51
 *
 * @author Don't bully Xiaobai, okay
 */
public class MyWindowListener implements WindowListener {
    @Override
    public void windowOpened(WindowEvent e) {

    }

    @Override
    public void windowClosing(WindowEvent arg0){
        System.out.println("window closing");
        System.exit(1);
    }

    @Override
    public void windowClosed(WindowEvent e) {

    }

    @Override
    public void windowIconified(WindowEvent e) {

    }

    @Override
    public void windowDeiconified(WindowEvent e) {

    }

    @Override
    public void windowActivated(WindowEvent e) {

    }

    @Override
    public void windowDeactivated(WindowEvent e) {

    }
}

package com.learnspringboot.libra.calculator;

import javax.swing.*;

/**
 * MyPanel class
 * Date: November 24, 2021
 * Time: 18:47
 *
 * @author Don't bully Xiaobai, okay
 */
public class MyPanelDraw {
    public MyPanelDraw(){

    }

    public JPanel getPanel(){
        JPanel jPanel = new JPanel();
        return jPanel;
    }
}

package com.learnspringboot.libra.calculator;

import com.learnspringboot.libra.frame.MyWindowListener;

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

/**
 * MyFrameDraw class
 * Date: November 24, 2021
 * Time: 7:59
 *
 * @author Don't bully Xiaobai, okay
 */
public class MyFrameDraw {
    public MyFrameDraw(int FrameWidth, int FrameHeight){
        JFrame frame = new JFrame();
        new SetFrame(frame,FrameWidth,FrameHeight);
        frame.setLayout(null);
        frame.add(getPanel01());
        frame.add(getPanel02());
        frame.add(getPanel03());

        frame.setVisible(true);
        frame.addWindowListener(new MyWindowListener());
    }

    public JPanel getPanel01(){
        JPanel jPanel = new JPanel(new FlowLayout());
        JTextField text = new JTextField(17);
        JButton cleanButton = new JButton("=");
        jPanel.add(text);
        jPanel.add(cleanButton);
        jPanel.setBounds(10,0,290,50);
        return  jPanel;
    }

    public JPanel getPanel02(){
        JPanel jPanel = new JPanel(new GridLayout(3,3));
        int end = 10;
        for (int i = 1; i < end; i++) {
            JButton but = new JButton(""+i);
            jPanel.add(but);
        }
        jPanel.setBounds(10,50,290,100);

        return jPanel;
    }

    public JPanel getPanel03(){
        JPanel jPanel = new JPanel(new GridLayout(2,3));
        jPanel.add(new Button(" 0"));
        jPanel.add(new Button("  +"));
        jPanel.add(new Button(" -"));
        jPanel.add(new Button(" *"));
        jPanel.add(new Button(" /"));
        jPanel.add(new Button(" ."));
        jPanel.setBounds(10,150,290,100);
        return jPanel;
    }

    public MyFrameDraw(){
        this(325,300);
    }
}

Summary

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