将图像添加到 JFrame

Question

So I am using Eclipse with Windows builder. I was just wondering if there was anyway I can import an image that'll show up on the JFrame that I can easily move around and re-size instead of setting the location and size and drawing it.

Answer 1

这是将图像添加到JFrame的简单示例：

frame.add(new JLabel(new ImageIcon("Path/To/Your/Image.png")));

Answer 2

There is no specialized image component provided in Swing (which is sad in my opinion). So, there are a few options:

1. As @Reimeus said: Use a JLabel with an icon.

2. Create in the window builder a JPanel, that will represent the location of the image. Then add your own custom image component to the JPanel using a few lines of code you will never have to change. They should look like this:

    JImageComponent ic = new JImageComponent(myImageGoesHere); imagePanel.add(ic);

   where JImageComponent is a self created class that extends JComponent that overrides the paintComponent() method to draw the image.

Answer 3

如果使用 Netbeans 开发，请使用 JLabel 并更改其图标属性。

Answer 4

As martijn-courteaux said, create a custom component it's the better option. In C# exists a component called PictureBox and I tried to create this component for Java, here is the code:

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JComponent;

public class JPictureBox extends JComponent {

    private Icon icon = null;
    private final Dimension dimension = new Dimension(100, 100);
    private Image image = null;
    private ImageIcon ii = null;
    private SizeMode sizeMode = SizeMode.STRETCH;
    private int newHeight, newWidth, originalHeight, originalWidth;

    public JPictureBox() {
        JPictureBox.this.setPreferredSize(dimension);
        JPictureBox.this.setOpaque(false);
        JPictureBox.this.setSizeMode(SizeMode.STRETCH);
    }

    @Override
    public void paintComponent(Graphics g) {
        if (ii != null) {
            switch (getSizeMode()) {
                case NORMAL:
                    g.drawImage(image, 0, 0, ii.getIconWidth(), ii.getIconHeight(), null);
                    break;
                case ZOOM:
                    aspectRatio();
                    g.drawImage(image, 0, 0, newWidth, newHeight, null);
                    break;
                case STRETCH:
                    g.drawImage(image, 0, 0, this.getWidth(), this.getHeight(), null);
                    break;
                case CENTER:
                    g.drawImage(image, (int) (this.getWidth() / 2) - (int) (ii.getIconWidth() / 2), (int) (this.getHeight() / 2) - (int) (ii.getIconHeight() / 2), ii.getIconWidth(), ii.getIconHeight(), null);
                    break;
                default:
                    g.drawImage(image, 0, 0, this.getWidth(), this.getHeight(), null);
            }
        }
    }

    public Icon getIcon() {
        return icon;
    }

    public void setIcon(Icon icon) {
        this.icon = icon;
        ii = (ImageIcon) icon;
        image = ii.getImage();
        originalHeight = ii.getIconHeight();
        originalWidth = ii.getIconWidth();
    }

    public SizeMode getSizeMode() {
        return sizeMode;
    }

    public void setSizeMode(SizeMode sizeMode) {
        this.sizeMode = sizeMode;
    }

    public enum SizeMode {
        NORMAL,
        STRETCH,
        CENTER,
        ZOOM
    }

    private void aspectRatio() {
        if (ii != null) {
            newHeight = this.getHeight();
            newWidth = (originalWidth * newHeight) / originalHeight;
        }
    }

}

If you want to add an image, choose the JPictureBox, after that go to Properties and find "icon" property and select an image. If you want to change the sizeMode property then choose the JPictureBox, after that go to Properties and find "sizeMode" property, you can choose some values:

• NORMAL value, the image is positioned in the upper-left corner of the JPictureBox.
• STRETCH value causes the image to stretch or shrink to fit the JPictureBox.
• ZOOM value causes the image to be stretched or shrunk to fit the JPictureBox; however, the aspect ratio in the original is maintained.
• CENTER value causes the image to be centered in the client area.

If you want to learn more about this topic, you can check this video .

Also you can see the code on Gitlab or Github .