将图像添加到JFrames的问题

Question

我一直在尝试将图像加载到jframe中.我不知道为什么这段代码不起作用.我尝试过使用jpanel和jlabels,以及其他加载图像的方法,但这些方法也不起作用.我认为因为这与我设置的JFrame有关.我想远离jpanels和jlabels,因为至少据我所知,它们无法扩展.如果有人有添加图像的解决方案,请告诉我.这是代码:

import java.awt.Canvas;
import javax.swing.JFrame;
import java.awt.*;
import javax.swing.ImageIcon;
import java.awt.event.KeyEvent;
import java.awt.Graphics;


public class Base extends Canvas implements Runnable {

    private static final long serialVersionUID = 001;
    private Image rock1;
    private Image rock2;
    private Image wood1;

    private Thread thread;
    private boolean running = (false);
    private boolean paused = (false);

    int x = 0;
    int y = 0;
    int z = 512;


    private void start() {
        if (running)
            return;
        running = true;
        thread = new Thread(this);
    }

    public void run(){}

    public Base(){}

    public static void main(String[] Args) {
        Base game = new Base();
        JFrame frame = new JFrame();
        frame.add(game);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(800, 600);
        frame.setLocationRelativeTo(null);
        frame.setResizable(false);
        frame.setVisible(true);
        frame.setTitle("Game");

        System.out.println("Running...");

        game.start();
        game.loadPics();

    }

    public void keyPressed(KeyEvent e) {
        if (e.getKeyCode() == KeyEvent.VK_A) {
            x = x - 5;
        }
        if (e.getKeyCode() == KeyEvent.VK_D) {
            x = x + 5;
        }
        if (e.getKeyCode() == KeyEvent.VK_SPACE) {
            y = y - 5;
        }
        if (e.getKeyCode() == KeyEvent.VK_SHIFT) {
            y = y + 5;
        }
        if (e.getKeyCode() == KeyEvent.VK_W) {
            z = z + 5;
        }
        if (e.getKeyCode() == KeyEvent.VK_S) {
            z = z - 5;
        }
        if (e.getKeyCode() == KeyEvent.VK_ESCAPE) {
            paused = (true);
        }
    }

    public void loadPics(){

        rock1 = new ImageIcon("C\\...\\rock1.png").getImage();
        rock2 = new ImageIcon("C\\...\\rock2.png").getImage();
        wood1 = new ImageIcon("C\\....\\wood1.png").getImage();

        repaint();
    }

    public void paint(Graphics g){
        while(paused = false){
        g.drawImage(rock1, x, y, z, z, this);
        g.drawImage(rock2, x + 512, y, z, z, this);
        g.drawImage(wood1, x, y + 512, z, z, this);

        try{
            Thread.sleep(16);
        }catch(Exception e){}
        g.dispose();
        }

    }
}

同样,我认为问题在于我的JFrame,但我不能太确定,因为我不是最有经验的java程序员.无论如何,如果您知道解决方案或需要更改的内容,请提供帮助.

Answer 1

这个说法

while (paused = false){

将始终评估false为您正在使用赋值表达式,因此drawImage不会发生后续调用.您可能打算使用==运算符来比较原始boolean值:

while (paused == false){

• 不要使用paint,paintComponent从子类使用JComponent
• 不要Thread.sleep用任何 paint方法打电话.Swing有自己的并发机制.Thread.sleep您可以使用Swing Timer定期执行图形更新,而不是在此处调用.

除此之外,AWT是重量级组件,使用轻量级Swing组件无法很好地渲染.使用键绑定而不是Key ListenersSwing应用程序.