我希望在运行程序时显示PNG。图像是单位圆。我用单位圆上的坐标排列方框。我尝试了各种方法，但它们不起作用。我不知道你是否可以在JFrame中使用paint方法，因为这可能会导致问题。我以前使用过PNG并且已经使用了PNG，但这只是在Applet中。我希望这可以在不改变代码的情况下工作。这是显示JFrame的类的代码：
public class UnitCircleReal {
public static void main(String[] args) {
// TODO Auto-generated method stub
UnitCircle uc = new UnitCircle();
uc.setVisible(true);
}
}
这是JFrame的代码，我想在这个类中添加图像：
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.MenuBar;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.net.URL;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class UnitCircle extends JFrame implements MouseListener, MouseMotionListener{
private static final long serialVersionUID = 1L;
URL url;
Image UnitCircle;
int x, y;
String s,a,b,c,d,e,f,g2,h,i,j,k,l,m,n,o,p,q,r,t,u,v,w,x2,y2,z;
boolean mouseInA = false;
boolean mouseInB = false;
boolean mouseInC = false;
boolean mouseInD = false;
boolean mouseInE = false;
boolean mouseInF = false;
boolean mouseInG = false;
boolean mouseInH = false;
boolean mouseInI = false;
boolean mouseInJ = false;
boolean mouseInK = false;
boolean mouseInL = false;
boolean mouseInM = false;
boolean mouseInN = false;
boolean mouseInO = false;
boolean mouseInP = false;
boolean mouseClickA = false;
boolean mouseClickB = false;
boolean mouseClickC = false;
boolean mouseClickD = false;
boolean mouseClickE = false;
boolean mouseClickF = false;
boolean mouseClickG = false;
boolean mouseClickH = false;
boolean mouseClickI = false;
boolean mouseClickJ = false;
boolean mouseClickK = false;
boolean mouseClickL = false;
boolean mouseClickM = false;
boolean mouseClickN = false;
boolean mouseClickO = false;
boolean mouseClickP = false;
public UnitCircle() {
setTitle("The Unit Circle!");
setSize(1350, 900);
setDefaultCloseOperation(EXIT_ON_CLOSE);
UnitCirclePic ucp = new UnitCirclePic();
addMouseMotionListener(this);
addMouseListener(this);
setVisible(true);
getContentPane().add(ucp);
}
public void paint(Graphics g) {
g.setColor(Color.WHITE);
g.fillRect(0, 0, getWidth(), getHeight());
s = "sine =";
a = "cosine =";
b = "tangent =";
c = "cosecant =";
d = "secant =";
e = "cotangent =";
f = "0";
g2 = "1";
h = "√3/2";
i = "-√3/2";
j = "und.";
k = "√2/2";
l = "-√2/2";
m = "1/2";
n = "-1/2";
o = "√2";
p = "-√2";
q = "2";
r = "-2";
t = "√3/3";
u = "-√3/3";
v = "-1";
w = "√3";
x2 = "-√3";
y2 = "2√3/3";
z = "-2√3/3";
Font font = new Font("Serif", Font.PLAIN, 32);
g.setFont(font);
g.setColor(Color.BLACK);
g.drawString(s, 900, 120);
g.drawString(a, 900, 250);
g.drawString(b, 900, 380);
g.drawString(c, 900, 510);
g.drawString(d, 900, 640);
g.drawString(e, 900, 770);
g.setColor(Color.RED);
g.drawRect(653, 400, 30, 30);//a
g.drawRect(625, 260, 30, 60);//b
g.drawRect(580, 210, 30, 60);//c
g.drawRect(520, 170, 30, 60);//d
g.drawRect(400, 140, 30, 65);//e
g.drawRect(273, 175, 35, 60);//f
g.drawRect(222, 214, 35, 60);//g
g.drawRect(180, 266, 35, 60);//h
g.drawRect(150, 400, 30, 30);//i
g.drawRect(175, 515, 35, 60);//j
g.drawRect(220, 570, 35, 60);//k
g.drawRect(273, 600, 35, 60);//l
g.drawRect(395, 610, 40, 80);//m
g.drawRect(520, 605, 35, 60);//n
g.drawRect(580, 570, 33, 60);//o
g.drawRect(616, 515, 38, 60);//p
if (mouseClickA){
g.setColor(Color.BLACK);
g.setFont(font);
g.drawString(f, 1000, 120);
g.drawString(g2, 1025, 250);
g.drawString(f, 1030, 380);
g.drawString(f, 1045, 510);
g.drawString(g2, 1025, 640);
g.drawString(j, 1060, 770);
}else if(mouseClickB){
g.setColor(Color.BLACK);
g.drawString(m, 1000, 120);
g.drawString(h, 1025, 250);
g.drawString(t, 1030, 380);
g.drawString(q, 1045, 510);
g.drawString(y2, 1025, 640);
g.drawString(w, 1060, 770);
}else if(mouseClickC){
g.setColor(Color.BLACK);
g.drawString(k, 1000, 120);
g.drawString(k, 1025, 250);
g.drawString(g2, 1030, 380);
g.drawString(o, 1045, 510);
g.drawString(o, 1025, 640);
g.drawString(g2, 1060, 770);
}else if(mouseClickD){
g.setColor(Color.BLACK);
g.drawString(h, 1000, 120);
g.drawString(m, 1025, 250);
g.drawString(w, 1030, 380);
g.drawString(y2, 1045, 510);
g.drawString(q, 1025, 640);
g.drawString(t, 1060, 770);
}else if(mouseClickE){
g.setColor(Color.BLACK);
g.drawString(g2, 1000, 120);
g.drawString(f, 1025, 250);
g.drawString(j, 1030, 380);
g.drawString(g2, 1045, 510);
g.drawString(f, 1025, 640);
g.drawString(f, 1060, 770);
}else if(mouseClickF){
g.setColor(Color.BLACK);
g.drawString(h, 1000, 120);
g.drawString(n, 1025, 250);
g.drawString(x2, 1030, 380);
g.drawString(y2, 1045, 510);
g.drawString(r, 1025, 640);
g.drawString(u, 1060, 770);
}else if(mouseClickG){
g.setColor(Color.BLACK);
g.drawString(k, 1000, 120);
g.drawString(l, 1025, 250);
g.drawString(v, 1030, 380);
g.drawString(o, 1045, 510);
g.drawString(p, 1025, 640);
g.drawString(v, 1060, 770);
}else if(mouseClickH){
g.setColor(Color.BLACK);
g.drawString(m, 1000, 120);
g.drawString(i, 1025, 250);
g.drawString(u, 1030, 380);
g.drawString(q, 1045, 510);
g.drawString(z, 1025, 640);
g.drawString(x2, 1060, 770);
}else if(mouseClickI){
g.setColor(Color.BLACK);
g.drawString(f, 1000, 120);
g.drawString(v, 1025, 250);
g.drawString(f, 1030, 380);
g.drawString(f, 1045, 510);
g.drawString(v, 1025, 640);
g.drawString(j, 1060, 770);
}else if(mouseClickJ){
g.setColor(Color.BLACK);
g.drawString(n, 1000, 120);
g.drawString(i, 1025, 250);
g.drawString(t, 1030, 380);
g.drawString(r, 1045, 510);
g.drawString(z, 1025, 640);
g.drawString(w, 1060, 770);
}else if(mouseClickK){
g.setColor(Color.BLACK);
g.drawString(l, 1000, 120);
g.drawString(l, 1025, 250);
g.drawString(g2, 1030, 380);
g.drawString(p, 1045, 510);
g.drawString(p, 1025, 640);
g.drawString(g2, 1060, 770);
}else if(mouseClickL){
g.setColor(Color.BLACK);
g.drawString(i, 1000, 120);
g.drawString(n, 1025, 250);
g.drawString(w, 1030, 380);
g.drawString(z, 1045, 510);
g.drawString(r, 1025, 640);
g.drawString(t, 1060, 770);
}else if(mouseClickM){
g.setColor(Color.BLACK);
g.drawString(v, 1000, 120);
g.drawString(f, 1025, 250);
g.drawString(j, 1030, 380);
g.drawString(v, 1045, 510);
g.drawString(f, 1025, 640);
g.drawString(f, 1060, 770);
}else if(mouseClickN){
g.setColor(Color.BLACK);
g.drawString(i, 1000, 120);
g.drawString(m, 1025, 250);
g.drawString(x2, 1030, 380);
g.drawString(z, 1045, 510);
g.drawString(q, 1025, 640);
g.drawString(u, 1060, 770);
}else if(mouseClickO){
g.setColor(Color.BLACK);
g.drawString(l, 1000, 120);
g.drawString(k, 1025, 250);
g.drawString(v, 1030, 380);
g.drawString(p, 1045, 510);
g.drawString(o, 1025, 640);
g.drawString(v, 1060, 770);
}else if(mouseClickP){
g.setColor(Color.BLACK);
g.drawString(n, 1000, 120);
g.drawString(h, 1025, 250);
g.drawString(u, 1030, 380);
g.drawString(z, 1045, 510);
g.drawString(y2, 1025, 640);
g.drawString(x2, 1060, 770);
}
}
@Override
public void mouseMoved(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mouseClicked(MouseEvent e) {
// TODO Auto-generated method stub
x = e.getX();
y = e.getY();
if(e.getX() > 653 && e.getX() < 683){
if(e.getY() > 400 && e.getY() < 430){
mouseInA = true;
mouseClickA = true;
repaint();
}
}
if(e.getX() < 653 || e.getX() > 683){
if(e.getY() < 400 || e.getY() > 430){
mouseInA = false;
mouseClickA = false;
}
}
if(e.getX() > 625 && e.getX() < 655){
if(e.getY() > 260 && e.getY() < 320){
mouseInB = true;
mouseClickB = true;
repaint();
}
}
if(e.getX() < 625 || e.getX() > 655){
if(e.getY() < 260 || e.getY() > 320){
mouseInB = false;
mouseClickB = false;
}
}
if(e.getX() > 580 && e.getX() < 610){
if(e.getY() > 210 && e.getY() < 270){
mouseInC = true;
mouseClickC = true;
repaint();
}
}
if(e.getX() < 580 || e.getX() > 610){
if(e.getY() < 210 || e.getY() > 270){
mouseInC = false;
mouseClickC = false;
}
}
if(e.getX() > 520 && e.getX() < 550){
if(e.getY() > 170 && e.getY() < 230){
mouseInD = true;
mouseClickD = true;
repaint();
}
}
if(e.getX() < 520 || e.getX() > 550){
if(e.getY() < 170 || e.getY() > 230){
mouseInD = false;
mouseClickD = false;
}
}
if(e.getX() > 400 && e.getX() < 430){
if(e.getY() > 140 && e.getY() < 205){
mouseInE = true;
mouseClickE = true;
repaint();
}
}
if(e.getX() < 400 || e.getX() > 430){
if(e.getY() < 140 || e.getY() > 205){
mouseInE = false;
mouseClickE = false;
}
}
if(e.getX() > 273 && e.getX() < 308){
if(e.getY() > 175 && e.getY() < 235){
mouseInF = true;
mouseClickF = true;
repaint();
}
}
if(e.getX() < 273 || e.getX() > 308){
if(e.getY() < 175 || e.getY() > 235){
mouseInF = false;
mouseClickF = false;
}
}
if(e.getX() > 222 && e.getX() < 257){
if(e.getY() > 214 && e.getY() < 274){
mouseInG = true;
mouseClickG = true;
repaint();
}
}
if(e.getX() < 222 || e.getX() > 257){
if(e.getY() < 214 || e.getY() > 274){
mouseInG = false;
mouseClickG = false;
}
}
if(e.getX() > 180 && e.getX() < 215){
if(e.getY() > 266 && e.getY() < 326){
mouseInH = true;
mouseClickH = true;
repaint();
}
}
if(e.getX() < 180 || e.getX() > 215){
if(e.getY() < 266 || e.getY() > 326){
mouseInH = false;
mouseClickH = false;
}
}
if(e.getX() > 150 && e.getX() < 180){
if(e.getY() > 400 && e.getY() < 430){
mouseInI = true;
mouseClickI = true;
repaint();
}
}
if(e.getX() < 150 || e.getX() > 180){
if(e.getY() < 400 || e.getY() > 430){
mouseInI = false;
mouseClickI = false;
}
}
if(e.getX() > 175 && e.getX() < 210){
if(e.getY() > 515 && e.getY() < 575){
mouseInJ = true;
mouseClickJ = true;
repaint();
}
}
if(e.getX() < 175 || e.getX() > 210){
if(e.getY() < 515 || e.getY() > 575){
mouseInJ = false;
mouseClickJ = false;
}
}
if(e.getX() > 220 && e.getX() < 255){
if(e.getY() > 570 && e.getY() < 630){
mouseInK = true;
mouseClickK = true;
repaint();
}
}
if(e.getX() < 220 || e.getX() > 255){
if(e.getY() < 570 || e.getY() > 630){
mouseInK = false;
mouseClickK = false;
}
}
if(e.getX() > 273 && e.getX() < 308){
if(e.getY() > 600 && e.getY() < 660){
mouseInL = true;
mouseClickL = true;
repaint();
}
}
if(e.getX() < 273 || e.getX() > 308){
if(e.getY() < 600 || e.getY() > 660){
mouseInL = false;
mouseClickL = false;
}
}
if(e.getX() > 395 && e.getX() < 435){
if(e.getY() > 610 && e.getY() < 690){
mouseInM = true;
mouseClickM = true;
repaint();
}
}
if(e.getX() < 395 || e.getX() > 435){
if(e.getY() < 610 || e.getY() > 690){
mouseInM = false;
mouseClickM = false;
}
}
if(e.getX() > 520 && e.getX() < 555){
if(e.getY() > 605 && e.getY() < 665){
mouseInN = true;
mouseClickN = true;
repaint();
}
}
if(e.getX() < 520 || e.getX() > 555){
if(e.getY() < 605 || e.getY() > 665){
mouseInN = false;
mouseClickN = false;
}
}
if(e.getX() > 580 && e.getX() < 613){
if(e.getY() > 570 && e.getY() < 630){
mouseInO = true;
mouseClickO = true;
repaint();
}
}
if(e.getX() < 580 || e.getX() > 613){
if(e.getY() < 570 || e.getY() > 630){
mouseInO = false;
mouseClickO = false;
}
}
if(e.getX() > 616 && e.getX() < 654){
if(e.getY() > 515 && e.getY() < 575){
mouseInP = true;
mouseClickP = true;
repaint();
}
}
if(e.getX() < 616 || e.getX() > 654){
if(e.getY() < 515 || e.getY() > 575){
mouseInP = false;
mouseClickP = false;
}
}
}
@Override
public void mouseDragged(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mousePressed(MouseEvent e) {
// TODO Auto-generated method stub
}
@Override
public void mouseReleased(MouseEvent e) {
// TODO Auto-generated method stub
}
}
答案 0 :(得分：3)
最简单的方法是使用JLabel作为图片持有人
JLabel imgLabel = new JLabel(new ImageIcon("path_to_image.png"));
add(imgLabel);