0

我正在制作一个可以从 Internet 加载图片的 JFrame。我有这个工作，但这个 JFrame 的问题是有很多图片，所以它们需要很长时间才能加载。这很好，但我想向用户展示图片正在加载。出于某种原因，我无法让 JPanel 在加载的 JFrame 中显示。我知道这是一个常见错误，我尝试了很多修复，但没有一个有效。这是代码：

final JFrame weatherLoadPop=new JFrame("Loading weather...");
weatherLoadPop.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
weatherLoadPop.addWindowListener(new WindowAdapter() {
   public void windowClosing(WindowEvent e) {
      weatherPop.dispose();
   };
});
weatherLoadPop.setResizable(false);
weatherLoadPop.setBounds(100,50,225,100);
JPanel weatherLoadPanel=new JPanel();
weatherLoadPanel.setBackground(Color.RED);

weatherLoadPanel.setPreferredSize(new Dimension(225,100));
JLabel weatherLoadLabel=new JLabel("Loading...0%");
weatherLoadPanel.add(weatherLoadLabel);
weatherLoadPop.add(weatherLoadPanel);
weatherLoadPop.pack();
weatherLoadPop.validate();
weatherLoadPop.setVisible(true);

我不确定我是否正确使用了 pack() 和 validate()。我不经常使用它们。在任何情况下，删除它们都无济于事。对我来说，这个问题最奇怪的部分是加载图片的 JFrame 工作得很好，而更简单的加载 JFrame 却没有。

谢谢你的帮助。

4

1 回答 1

1

它在这里工作正常。也许您应该提供一个我们可以测试的sscce ？

我不得不更改您的事件侦听器以处理 weatherLoadPop 而不是 weatherPop 并将您的代码添加到测试类中：

package test;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class Test {

    public static void main(String[] args) {
        final JFrame weatherLoadPop = new JFrame("Loading weather...");
        weatherLoadPop.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        weatherLoadPop.addWindowListener(new WindowAdapter() {

            @Override
            public void windowClosing(WindowEvent e) {
                weatherLoadPop.dispose();
            }
        ;
        });
        weatherLoadPop.setResizable(false);
        weatherLoadPop.setBounds(100, 50, 225, 100);
        JPanel weatherLoadPanel = new JPanel();
        weatherLoadPanel.setBackground(Color.RED);

        weatherLoadPanel.setPreferredSize(new Dimension(225, 100));
        JLabel weatherLoadLabel = new JLabel("Loading...0%");
        weatherLoadPanel.add(weatherLoadLabel);
        weatherLoadPop.add(weatherLoadPanel);
        weatherLoadPop.pack();
        weatherLoadPop.validate();
        weatherLoadPop.setVisible(true);
    }
}

我得到：

加载中......

使用：

java version "1.7.0_04"
Java(TM) SE Runtime Environment (build 1.7.0_04-b20)
Java HotSpot(TM) 64-Bit Server VM (build 23.0-b21, mixed mode)
于 2012-07-05T15:05:38.330 回答