我有一个带有多个JFrames的程序。我想只在其中一个上画线。这是一个简单的刽子手程序，所以只有实际的游戏页面上应该有这些行。 （这些线条将构成套索部分，因此每次都应该立即绘制。）尝试根据我发现的其他类似QA向相关的JFrame添加一个画家类，但它似乎不起作用。
package hangman;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import javax.swing.*;
import javax.swing.JPanel;
import javax.swing.BorderFactory;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
class Painter extends JPanel{
public Painter(){
}
@Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
g.drawString("This is a test.",50,50);
g.drawLine(20, 80, 20, 200);
}
}
public class Hangman{
public static void main(String[] args) throws InterruptedException{
hangman();
}
// method: hangman()
// purpose: create windows that make the Hangman game
private static void hangman() {
//Timer
final DateFormat dateFormat = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
int interval = 1000; // 1000 ms
Calendar now = Calendar.getInstance();
JLabel time = new JLabel(dateFormat.format(now.getTime()));
time.setBounds(450, -50, 200, 125);
Timer timer = new Timer(interval, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
Calendar now = Calendar.getInstance();
time.setText(dateFormat.format(now.getTime()));
}
});
timer.start();
//Frames
JFrame titleFrame = new JFrame("Hangman");
JFrame mainMenuFrame = new JFrame("Hangman");
JFrame creditsFrame = new JFrame("Hangman");
JFrame highScoreFrame = new JFrame("Hangman");
JFrame playGame = new JFrame("Hangman");
creditsFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
titleFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainMenuFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
highScoreFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
playGame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Labels
final JLabel titleText = new JLabel();
final JLabel teamText = new JLabel();
final JLabel jennaBarrett = new JLabel();
final JLabel lennyYang = new JLabel();
final JLabel rachelFrodsham = new JLabel();
final JLabel titleCredit = new JLabel();
final JLabel highScores = new JLabel();
final JLabel hangmanTitle = new JLabel();
ImageIcon pastaIcon = new ImageIcon("Images/pasta.png");
JLabel pastaImage = new JLabel(pastaIcon);
titleText.setText("CS245 Quarter Project");
titleCredit.setText("Credits");
teamText.setText("By: Pasta Party");
jennaBarrett.setText("Jenna Barret, 010805821");
lennyYang.setText("Lenny Yang, 010265034");
rachelFrodsham.setText("Rachel Frodsham, 009922783");
highScores.setText("High Scores");
hangmanTitle.setText("Hangman");
titleText.setFont(new Font("Arial", Font.BOLD, 30));
titleCredit.setFont(new Font("Arial", Font.BOLD, 20));
highScores.setFont(new Font("Arial", Font.BOLD, 20));
hangmanTitle.setFont(new Font("Serif", Font.BOLD, 40));
//Buttons
JButton playButton = new JButton("Play");
JButton highScoreButton = new JButton("High Score");
JButton creditsButton = new JButton("Credits");
JButton backButtonCF = new JButton("Back");
JButton backButtonHS = new JButton("Back");
//Positioning
titleText.setBounds(130,50,500,150);
teamText.setBounds(250,300,200,50);
teamText.setBounds(250,300,150,50);
playButton.setBounds(400,185,150,30);
highScoreButton.setBounds(400,235,150,30);
creditsButton.setBounds(400,285,150,30);
backButtonHS.setBounds(25,300,95,30);
backButtonCF.setBounds(25,300,95,30);
jennaBarrett.setBounds(250,125,200,100);
lennyYang.setBounds(250,150,200,100);
rachelFrodsham.setBounds(250,175,200,100);
pastaImage.setBounds(10, 0, 400, 400);
titleCredit.setBounds(250,75,100,100);
highScores.setBounds(250,10,300,150);
hangmanTitle.setBounds(25,-10,500,100);
//Listeners
new java.util.Timer().schedule(new java.util.TimerTask() {
@Override
public void run() {
titleFrame.setVisible(false);
mainMenuFrame.setVisible(true);
}
},
4500
);
highScoreButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
mainMenuFrame.setVisible(false);
highScoreFrame.setVisible(true);
}
});
playButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
mainMenuFrame.setVisible(false);
playGame.setVisible(true);
}
});
creditsButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
mainMenuFrame.setVisible(false);
creditsFrame.setVisible(true);
}
});
backButtonCF.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
creditsFrame.setVisible(false);
mainMenuFrame.setVisible(true);
}
});
backButtonHS.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
highScoreFrame.setVisible(false);
mainMenuFrame.setVisible(true);
}
});
//Title Frame
titleFrame.setSize(600,400);
titleFrame.add(titleText);
titleFrame.add(teamText);
titleFrame.setLayout(null);
titleFrame.setLocationRelativeTo(null);
titleFrame.setVisible(true);
//Main Frame
mainMenuFrame.setSize(600,400);
mainMenuFrame.add(playButton);
mainMenuFrame.add(highScoreButton);
mainMenuFrame.add(creditsButton);
mainMenuFrame.add(pastaImage);
mainMenuFrame.setLayout(null);
mainMenuFrame.setLocationRelativeTo(null);
//Play Frame
playGame.setSize(600,400);
playGame.add(hangmanTitle);
playGame.setLayout(null);
playGame.add(time);
playGame.setLocationRelativeTo(null);
Painter p = new Painter();
p.setVisible(true);
playGame.add(p);
//Credits Frame
creditsFrame.setSize(600,400);
creditsFrame.add(titleCredit);
creditsFrame.add(jennaBarrett);
creditsFrame.add(lennyYang);
creditsFrame.add(rachelFrodsham);
creditsFrame.add(backButtonCF);
creditsFrame.setLayout(null);
creditsFrame.setLocationRelativeTo(null);
//High Scores Frame
highScoreFrame.setSize(600,400);
highScoreFrame.add(highScores);
highScoreFrame.add(backButtonHS);
highScoreFrame.setLayout(null);
highScoreFrame.setLocationRelativeTo(null);
}
}
//
答案 0 :(得分：3)
playGame.setLayout(null);搞砸了你，因为当使用空布局你完全负责组件的完整定位和大小调整，而你没有设置大小或“边界”你的画家JPanel。注释掉这一行，看看我的意思。
但 你应该设置它的大小，因为一般来说，不要使用null布局，而是学会使用布局管理器。虽然null布局和setBounds()似乎是Swing新手，比如创建复杂GUI的最简单和最好的方法，但是你创建的Swing GUI越多，在使用它们时会遇到更严重的困难。当GUI调整大小时，它们不会调整组件的大小，它们是增强或维护的皇室女巫，当它们被放置在滚动窗格中时它们完全失败，当它们在所有平台上观看时或者与原始平台不同的屏幕分辨率时它们看起来很糟糕
“我有一个带有多个JFrames的程序”
关键相关问题的强制性链接：The Use of Multiple JFrames, Good/Bad Practice?。所以，如果您不想完全惹恼您的应用程序的用户，请在此处使用CardLayout。
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