.png图标未加载到JFrame窗口中

Question

import java.awt.*;
import javax.swing.*;

public class Program {
public static JButton button;
public static void main(String args[]){
    JFrame win=new JFrame("title");
    win.setVisible(true);
    win.setSize(500,500);
    win.setLayout(new FlowLayout());
    win.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    ImageIcon i=new ImageIcon("icon.png");
    button=new JButton("hello",i);
    win.add(button);
    button.setToolTipText("click me");

}
}

When I run the file , I just get the text "hello" on the button but no image.
(This image was downloaded from http://icons.iconarchive.com/icons/iynque/flat-ios7-style-documents/512/png-icon.png )

The image is stored in the project src file.

Answer 1

Image shouldn't be in src but in main application directory, usually level above. So move your icon or change code to:

ImageIcon i=new ImageIcon("src/icon.png");

You should consider adding it to your resources (so it will be placed in jar) and opening via getResource() . Next problem in example is that it won't be displayed until window is refreshed by resize or other action. Add this line at the end:

win.pack();

Or other method that will refresh window content.

Answer 2

试试这个：ImageIcon i = new ImageIcon（“ src / icon.png”）;

Answer 3

getClass().getResource("icon.png")

如果您的图像文件位于Program.java的同一目录下，并且在编译时确实将其打包到与Program.class相同的目录下，则将执行此操作。