Question

我尝试使用cookie.setLocation(x,y)。我将面板的布局设置为null，但它似乎不起作用。我究竟做错了什么？运行时，窗口上没有任何内容。我设定尺寸所以不可能。

import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
import javax.swing.Timer;
import javax.swing.border.Border;
import java.util.*;
public class menus extends JPanel implements ActionListener{
    JPanel p=new JPanel();
    JPanel p2=new JPanel();
    JLabel lbl=new JLabel();
    JLabel lblpr=new JLabel();
    Boolean fin=true;
    Boolean fin2=true;
    Boolean fin3=true;
    Boolean fin4=true;
    int g=5;
    int x=0;
    JLabel lbl2=new JLabel();
    int seconds=0;
    Timer t=new Timer(1000,this);
    int counter=0;
    ImageIcon image = new ImageIcon();
    public menus(){
        lblpr=new JLabel("");
        p.setLayout(null);
        image = new ImageIcon(getClass().getResource(""));
        JButton cookie = new JButton(new ImageIcon(getClass().getResource("cookie-1.gif")));
        Border emptyBorder = BorderFactory.createEmptyBorder();
        p.add(cookie);
        JButton b=new JButton("Buy Grandma(40 cookies)");
        p.add(b);
        cookie.setSize(200,200);
        cookie.setLocation(100,100);
        b.setSize(200,200);
        b.setLocation(100,100);
        p.add(lblpr);
        b.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                if(counter>=40){
                    if(x<5){
                        t.start();
                        counter-=40;
                        x++;
                    }else{
                        JOptionPane.showMessageDialog(null, "You bought a maximum of 5 grandmas. To win the game get 200 cookies!");
                    }
                }else{
                    JOptionPane.showMessageDialog(null, "Error you do not have enought cookies to buy a grandma");
                }
            }
        });
        cookie.setBorder(emptyBorder);
        cookie.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                counter++;
                if(counter>=200 && fin==true){
                    fin=false;
                    JOptionPane.showMessageDialog(null, "Woo.. now... em... idk... exit? "
                            + "I mean you must keep on going....."
                            + "\nNext goal 10000 can u do it? i dont think u have the balls to do it");
                    g=1000;
                }
                if(counter>=10000 && fin2==true){
                    fin2=false;
                    JOptionPane.showMessageDialog(null, "Wow... you do got the balls afterall... Well next one is 100000. Ok i dont think you will actually do this one.. "
                            + "\ni mean 5 grandmas by ur side only.. well let me give u a little help since we are getting along. I present u the ULTIMATE GRANDMA. This grandma will give you 300 cookies/s so yeah.. \nGood luck and see you at 100000");
                    g=305;
                }
                if(counter>=100000 && fin3==true){
                    fin3=false;
                    JOptionPane.showMessageDialog(null, "Really? Still playing? jeez... ok i guess the LAST goal is 1 Million.. See you there for ur price. oh yeah heres the BADASS ULTIMATE GRANDMA. 1000 cookies/s.");
                    g=1305;
                }
                if(counter>=1000000 && fin4==true){
                    fin4=false;
                    JOptionPane.showMessageDialog(null, "Well wow.. you really really did it didnt u? Ok here is ur prize.. press ok to claim");
                    ImageIcon i=new ImageIcon(getClass().getResource("Screenshot_1.png"));
                    lblpr.setIcon(i);

                }
                lbl.setText("You have "+counter+" Cookies!");
            }
        });
        lbl = new JLabel("");
        p.add(lbl);
        add(p);
    }
    public void actionPerformed(ActionEvent e){

        if(x==1){
        counter++;
        lbl.setText("You have "+counter+" Cookies!");
        }else if(x==2){
            counter+=2;
            lbl.setText("You have "+counter+" Cookies!");
        }else if(x==3){
            counter+=3;
            lbl.setText("You have "+counter+" Cookies!");
        }else if(x==4){
            counter+=4;
            lbl.setText("You have "+counter+" Cookies!");
        }else if(x==5){
            counter+=g;
            lbl.setText("You have "+counter+" Cookies!");
        }
    }
    public static void main(String Args[]){
        menus gui = new menus();
        JFrame jf = new JFrame();
        jf.setTitle("Yo");
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        jf.setSize(1280,720);
        jf.setVisible(true);
        jf.setResizable(false);
        jf.getContentPane().add(gui);
    }
}

Answer 1

我在这里看到两种可能性：

删除p

摆脱中级p JPanel。

您正在使用menus（默认），FlowLayout JPanel添加p JPanel。没有任何内容告诉menus您的p JPanel的大小是多少，因此它的大小为0/0。

然后您将menus添加到内容窗格，这是可以的，因为内容窗格通常有默认的BorderLayout。

您的menus面板将填充内容窗格的所有表面，很遗憾，其中没有任何内容可见（由于p的首选大小为0）。

因此，请删除p，然后直接在menus面板上添加和填充所有组件。

更改menus布局

您也可以只更改menus的默认布局：

 setLayout(new BorderLayout());

此处，当您要添加p（默认情况下为BorderLayout.CENTER）时，它将填充menus的整个表面。

然后，当您向内容窗格添加（默认情况下为BorderLayout.CENTER）menus时也是如此，因为内容窗格也有BorderLayout。

Answer 2

如果您想手动设置元素的Location和Size而没有任何LayoutManager，则需要进行后续处理。
将menus extends JPanel课程的布局设置为null。并设置Size的{{1}}和Location。

JPanel p

我在代码中看到的另一个问题是，您将Button和Cookie设置在相同大小的相同位置。所以你不会看到他们两个与您要添加到此面板而没有布局的任何其他元素一样，您需要设置p.setSize(800,300); p.setLocation(0,0); setLayout(null);的{{1}}和Location个但我真的需要提到的是，不使用布局管理器就是BAD设计！

为什么我的setLocation（x，y）不起作用？

2 个答案: