问题描述
所以我想在每次按下按钮时替换JLabel中的ImageIcon。我做了它，因此图像，标签和GridBagConstraints是公开的。当我尝试改变它时，虽然没有任何反应。
So I want to replace an ImageIcon in a JLabel every time a button is pressed. I made it so the image, label, and GridBagConstraints are public. When I try to change it though nothing happens.
我是以错误的方式进行此操作还是？
Am I going about this the wrong way or?
谢谢！
package hi.low;
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import javax.swing.*;
import java.util.Random;
import java.util.ArrayList;
public class Card_panel extends JPanel implements ActionListener
{
private final int WIDTH = 400, HEIGHT = 200;
private static String[] imageList = {
"images/2h.png", "images/3h.png", "images/4h.png", "images/5h.png", "images/6h.png",
"images/7h.png", "images/8h.png", "images/9h.png", "images/th.png", "images/jh.png",
"images/qh.png", "images/kh.png", "images/ah.png", "images/2d.png", "images/3d.png",
"images/4d.png", "images/5d.png", "images/6d.png", "images/7d.png", "images/8d.png",
"images/9d.png", "images/td.png", "images/jd.png", "images/qd.png", "images/kd.png",
"images/ad.png", "images/2c.png", "images/3c.png", "images/4c.png", "images/5c.png",
"images/6c.png", "images/7c.png", "images/8c.png", "images/9c.png", "images/tc.png",
"images/jc.png", "images/qc.png", "images/kc.png", "images/ac.png", "images/2s.png",
"images/3s.png", "images/4s.png", "images/5s.png", "images/6s.png", "images/7s.png",
"images/8s.png", "images/9s.png", "images/ts.png", "images/js.png", "images/qs.png",
"images/ks.png", "images/as.png"
};
private static int imageNum = -1;
GridBagConstraints gbc = new GridBagConstraints();
GridBagConstraints c = new GridBagConstraints();
ImageIcon image;
JLabel label;
private static ArrayList<Card> deck;
private static Card tempCard, currentCard;
public Card_panel()
{
deck = new ArrayList();
char[] suits = {'h', 'd', 'c', 's'};
char[] values = {'2', '3', '4', '5', '6', '7', '8', '9', 't', 'j', 'q', 'k', 'a'};
for(int a = 0; a<suits.length; a++)
{
for(int b = 0; b<values.length; b++)
{
tempCard = new Card(suits[a],values[b]);
deck.add(tempCard);
}
}
int rand_num;
int cards_left = 52;
Random generator = new Random( System.currentTimeMillis() );
for(int a = 0; a<52; a++)
{
rand_num = generator.nextInt(cards_left);
currentCard = deck.get(rand_num);
deck.remove(rand_num);
cards_left -= 1;
}
setPreferredSize(new Dimension(WIDTH, HEIGHT));
setBackground (Color.green.darker().darker());
setLayout(new GridBagLayout());
gbc.gridx = 0;
gbc.gridy = 0;
gbc.gridwidth = 2;
image = new ImageIcon(imageList[0]);
label = new JLabel("", image, JLabel.CENTER);
add( label, gbc );
gbc.gridx = 0;
gbc.gridy++;
gbc.gridwidth = 1;
JButton higher = new JButton("Higher");
higher.setActionCommand("higher");
higher.addActionListener (this);
add( higher, gbc );
gbc.gridx++;
JButton lower = new JButton("Lower");
lower.setActionCommand("lower");
lower.addActionListener (this);
add( lower, gbc );
}
@Override
public void actionPerformed(ActionEvent e)
{
String Action;
Action = e.getActionCommand ();
if (Action.equals ("higher"))
{
System.out.println("User chose higher!");
//function to check if it is right if right go to next card
image = new ImageIcon(imageList[1]);
label = new JLabel("", image, JLabel.CENTER);
add( label, gbc );
}
if (Action.equals ("lower"))
{
System.out.println("User chose lower!");
//function to check if it is right if right go to next card
}
}
}
推荐答案
而不是每次都尝试创建并添加新标签，只需调用 setIcon 在标签上
Rather then trying to create and add a new label each time, simply call setIcon on the label itself
更像是......
image = new ImageIcon(imageList[1]);
label.setIcon(image);
查看获取更多详细信息。
Check out How to use lables for more details.
我可能还建议你加载图片首先，所以你不需要继续重新加载它们/在每个 actionPerformed上创建新对象
I might also suggest that you load the images first, so you don't need to keep reloading them/creating new objects on each actionPerformed
我会还建议 over ImageIcon
这篇关于单击按钮将ImageIcon更改为另一张图片的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！