Question

我正在尝试从单独的类文件中加载随机图像。

import java.util.*;
import java.io.*;
public class random { 
    static String back01;

    public static void ran(int number) {
        switch(number) {
            case 1:
                setImage("images/01.jpg");
                break;
            case 2:
                setImage("images/02.jpg");
                break;
            case 3:
                setImage("images/03.jpg");
                break;
            case 4:
                setImage("images/04.jpg");
                break;
            case 5:
                setImage("images/05.jpg");
                break;
            case 6:
                setImage("images/06.jpg");
                break;
            case 7:
                setImage("images/07.jpg");
                break;
            case 8:
                setImage("images/08.jpg");
                break;
            case 9:
                setImage("images/09.jpg");
                break;
            case 10:
                setImage("images/10.jpg");
                break;
            default:
                System.out.println("Invalid number");
        }
    }

    public static void setImage(String back01) {
        String image = back01;
    }

    public static int getImage() {
        String test;
        String set = setImage(test);
        return set;
    }
}

我遇到了如何将函数调用到我的主类，无论我做什么，我在编译时都会遇到不兼容的类型错误。如果在我回家的时候通过备份我的代码来访问我的usb，那么我将发布一个与此执行相关的代码块。

int number = rand.nextInt(10) + 1;
random.ran(number);

然后我尝试使用

将它放到imageicon

.getResource(random.getImage());

然后它会通过一个错误说我在该函数中没有空白这是我的主要功能，最后可以访问我的代码。

/**
 * Write a description of class main here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import sun.audio.*;
import java.util.*;
public class test
{
    private static final int WIDTH = 800;
    private static final int HEIGHT = 600;

JButton start, exit;

static String back, back01;

Random rand = new Random();

private ExitButtonHandler ebHandler;
//private StartButtonHandler sbHandler;
public test()
{
    int test = rand.nextInt(10) + 1;

    random.ran(test);

    /*switch(rand_background)
    {
        case 1:
            back = "images/01.jpg";
            break;
        case 2:
            back = "images/02.jpg";
            break;
        case 3:
            back = "images/03.jpg";
            break;
        case 4:
            back = "images/04.jpg";
            break;
        case 5:
            back = "images/05.jpg";
            break;
        case 6:
            back = "images/06.jpg";
            break;
        case 7:
            back = "images/07.jpg";
            break;
        case 8:
            back = "images/08.jpg";
            break;
        case 9:
            back = "images/09.jpg";
            break;
        case 10:
            back = "images/10.jpg";
            break;
        default:
            System.out.println("Invalid number");
    }

    int rand_background01 = rand.nextInt(10) + 1;*/



    JFrame frame = new JFrame("Until the End: The Fallen Souls");
    //sound.music("music/theme01.wav");

    String testing = random.getImage() + "";

    ImageIcon image = new ImageIcon(getClass().getResource(random.getImage()));

    //ImageIcon image01 = new ImageIcon(getClass().getResource(back01));

    start = new JButton("Start game...");
    exit = new JButton("Exit game...");

    JLabel background = new JLabel();
    background.setIcon(image);
    background.setLayout(new BorderLayout());

    JLabel background01 = new JLabel();
    //background01.setIcon(image01);
    //background01.setLayout(new BorderLayout());

    JPanel panel = new JPanel();

    panel.add(background);
    //panel.add(background01);

    panel.setLayout(new GridBagLayout());

    panel.setOpaque(false);

    ebHandler = new ExitButtonHandler();

    exit.addActionListener(ebHandler);

    panel.add(start);
    panel.add(Box.createRigidArea(new Dimension(150, 0)));
    panel.add(exit);


    frame.add(panel);

    frame.setExtendedState(JFrame.MAXIMIZED_BOTH);

    frame.setUndecorated(true);
    frame.setVisible(true);
}

public class ExitButtonHandler implements ActionListener
{
    public void actionPerformed(ActionEvent e)
    {
        System.exit(0);
    }
}

public static void main(String args[])
{
    test menu = new test();

}
}

使用此代码，我现在通过更改背景来尝试非常基本的程序生成。当我走的时候会更复杂但是现在我们还没有创建任何瓷砖，所以我不能深入了解代码，直到我有一些东西可以试验。

编辑：

我设法让它工作，但我不得不删除我的setImage方法。有没有办法将其纳入其中？我的代码看起来比这个好多了

/**
 * Write a description of class random here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
import java.util.*;
import java.io.*;
public class random
{
public static String back01;
public static void ran(int number)
{
    switch(number)
    {
        case 1:
            back01 = "images/01.jpg";
            break;
        case 2:
            back01 = "images/02.jpg";
            break;
        case 3:
            back01 = "images/03.jpg";
            break;
        case 4:
            back01 = "images/04.jpg";
            break;
        case 5:
            back01 = "images/05.jpg";
            break;
        case 6:
            back01 = "images/06.jpg";
            break;
        case 7:
            back01 = "images/07.jpg";
            break;
        case 8:
            back01 = "images/08.jpg";
            break;
        case 9:
            back01 = "images/09.jpg";
            break;
        case 10:
            back01 = "images/10.jpg";
            break;
        default:
            System.out.println("Invalid number");
    }
}

public static void setImage(String back01)
{
    back01 = random.back01;
}

public static String getImage()
{
    return random.back01;
}
}

当我尝试使用System.out.println（random.getImage（））时，我会在back01前面带有和不带随机的null

EDIT /解决：

我明白了！谢谢大家的指导。这是我修复setImage函数的方法。

/**
 * Write a description of class random here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
import java.util.*;
import java.io.*;
public class random
{
public static String back01;
public static String test;
public static void ran(int number)
{
    switch(number)
    {
        case 1:
            setImage("images/01.jpg");
            break;
        case 2:
            setImage("images/02.jpg");
            break;
        case 3:
            setImage("images/03.jpg");
            break;
        case 4:
            setImage("images/04.jpg");
            break;
        case 5:
            setImage("images/05.jpg");
            break;
        case 6:
            setImage("images/06.jpg");
            break;
        case 7:
            setImage("images/07.jpg");
            break;
        case 8:
            setImage("images/08.jpg");
            break;
        case 9:
            setImage("images/09.jpg");
            break;
        case 10:
            setImage("images/10.jpg");
            break;
        default:
            System.out.println("Invalid number");
    }
}

public static void setImage(String back01)
{
    test = back01;
}

public static String getImage()
{
    return test;
}
}

Answer 1

为什么当方法签名将返回类型显示为int？

时，您的方法是否尝试返回String

    public static int getImage() {
       String test;
       String set = setImage(test);
       return set;
    }

Answer 2

你应该有这样的东西：

import java.util.*;
import java.io.*;
public class Random 
{ 
    private String back01;

    public static void ran(int number) {
        switch(number) {
            //All options
        }
    }

    //If you only use "setImage()" in the class is not necessary
    //declare this one as "public static"
    //public static void setImage(String back01) {
    private void setImage(String back01) {
        this.back01 = back01;
    }

    public static String getImage() {
        return back01;
    }
}

然后证明：

int number = rand.nextInt(10) + 1;
random.ran(number);
.getResource(random.getImage());

从单独的java文件显示图像

2 个答案: