[명품 JAVA ESSENTIAL] CH8 실습문제

"개정판: 명품 JAVAESSENTIAL(황기태)"교재에 수록된 문제들을 풀어서 올립니다. 문제의 번호만 표기하고 답안만 적는 형태로 업로드 하고있습니다. 개인 풀이이므로 오답이 있을 수 있으며 오답 발견 시 댓글 남겨주시면 감사하겠습니다😊 - #이 표시된 건 아직 풀지 못한 문제 or 헷갈리는 문제입니다! 추후에 다시 풀어서 올릴 예정이에요! -ujeyhx-

 

🔎실습문제

 

 

 

1) 

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

public class TEST2 extends JFrame {
	public TEST2() {
		setTitle("Let's study java");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		setSize(400,200);
		setVisible(true);
	
}



public static void main (String[] args) {
	new TEST2();
}
}

---

2)

 

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

public class TEST2 extends JFrame {
	public TEST2() {
		setTitle("BorderLayout Practice");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
		Container c = getContentPane();
		
		c.setLayout(new BorderLayout(50,5)); //수평수직 간격
		c.add(new JButton("Center"),BorderLayout.CENTER);
		c.add(new JButton("South"),BorderLayout.SOUTH);
		c.add(new JButton("North"),BorderLayout.NORTH);
		c.add(new JButton("East"),BorderLayout.EAST);
		c.add(new JButton("West"),BorderLayout.WEST);
		
		
		setSize(500,300);
		setVisible(true);
	
}



public static void main (String[] args) {
	new TEST2();
}
}

 

---

3)

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

public class TEST2 extends JFrame {
	public TEST2() {
		setTitle("FlowLayout Practice");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
		Container c = getContentPane();
		
		c.setLayout(new FlowLayout());
		
		c.add(new JLabel("100 + 200"));
		c.add(new JButton("="));
		c.add(new JLabel("300"));
		
		setSize(400,100);
		setVisible(true);
	
}



public static void main (String[] args) {
	new TEST2();
}
}

---

 

4)

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

public class TEST2 extends JFrame {

	public TEST2() {
		
		setTitle("Ten Color");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
	
		Container c = getContentPane();	
		c.setLayout(new GridLayout(1,10));
		
	
	
		Color [] cl = {Color.RED, Color.ORANGE, Color.YELLOW, 
				Color.GREEN, Color.CYAN, Color.BLUE, Color.MAGENTA, Color.GRAY,
				Color.PINK, Color.LIGHT_GRAY};

		for(int i=0; i<10; i++) {
			
			JButton btn = new JButton(Integer.toString(i));
			btn.setOpaque(true); //배경색 보이게 설정
			btn.setBackground(cl[i]);

			
			c.add(btn); 
		}
	
		setSize(500,300);
		setVisible(true);
}



public static void main (String[] args) {
	new TEST2();
}
}

---

5)

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

public class TEST2 extends JFrame {

	public TEST2() {
		
		setTitle("4x4");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
	
		Container c = getContentPane();	
		c.setLayout(new GridLayout(4,4));
		
	
		JLabel [] la = new JLabel[16];
		Color [] color = {Color.RED, Color.ORANGE, Color.YELLOW, Color.GREEN,
				Color.CYAN, Color.BLUE, Color.MAGENTA, Color.GRAY,
				Color.PINK, Color.LIGHT_GRAY, Color.WHITE, Color.DARK_GRAY,
				Color.BLACK, Color.ORANGE, Color.BLUE,Color.MAGENTA}; 


		for(int i=0; i<=15; i++) {
			
			la[i] = new JLabel(Integer.toString(i));
			la[i].setOpaque(true); //배경색 보이게 설정
			la[i].setBackground(color[i]);

			c.add(la[i]); 
		}
	
		setSize(500,300);
		setVisible(true);
}



public static void main (String[] args) {
	new TEST2();
}
}

 

 

---

6)

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

public class TEST2 extends JFrame {

	public TEST2() {
		
		setTitle("Rd");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
	
		Container c = getContentPane();	
	
		
		for(int i=0; i<20; i++) {
			
		JLabel la = new JLabel(Integer.toString(i));
		int x = (int)(Math.random()*220) +30;
		int y = (int)(Math.random()*220) +30;
		
		la.setLocation(x,y);
		la.setSize(20,20);
		la.setForeground(Color.MAGENTA);
		
		c.add(la);
		}
	
		
		setSize(300,400);
		setVisible(true);
}



public static void main (String[] args) {
	new TEST2();
}
}

 

---

7) 기능 구현은 따로 안 했고, 레이아웃만 만들었습니당 👩

 

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


class TopPanel extends JPanel {
	public TopPanel () {
		setLayout(new FlowLayout());
		add(new JButton("새로배치"));
		add(new JButton("종료"));
		
	}
}

class CenterPanel extends JPanel {
	public CenterPanel () {

		setLayout(null);
		for(int i=0; i<10; i++) {
		JLabel la = new JLabel("*");
		int x = (int)(Math.random()*220) +30;
		int y = (int)(Math.random()*220) +30;
		la.setLocation(x,y);
		la.setSize(20,20);
		la.setForeground(Color.MAGENTA);
		add(la);
		}
		
	}
}


class BottomPanel extends JPanel {
	public BottomPanel () {
		setLayout(new FlowLayout());
		add(new JButton("별개수 수정"));
		add(new JTextField(12));
	}
}



public class TEST2 extends JFrame {

	public TEST2() {
		
		setTitle("3개의 패널");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
		add(new TopPanel(), BorderLayout.NORTH); 
		add(new CenterPanel(), BorderLayout.CENTER); 
		add(new BottomPanel(), BorderLayout.SOUTH); 

		setSize(300,400);
		setVisible(true);
}



public static void main (String[] args) {
	new TEST2();
}
}