如何在可滚动的 JFrame 中打印所有摆动组件

Question

我正在尝试打印一个表单，该表单由可滚动JFrame中的摆动组件组成。我已经尝试了下面的代码来做到这一点，但我得到的打印只是窗口中当前滚动的区域。我需要打印整个页面。

法典：

public int print(Graphics arg0, PageFormat arg1, int arg2) throws PrinterException {
    // TODO Auto-generated method stub
    //return 0;
    if (arg2 > 0) { /* We have only one page, and 'page' is zero-based */
        return NO_SUCH_PAGE;
    }
    Graphics2D g2d = (Graphics2D)arg0;
    g2d.translate((int)arg1.getImageableX(), (int)arg1.getImageableY());  
    float pageWidth = (float)arg1.getImageableWidth();  
    float pageHeight = (float)arg1.getImageableHeight();  
    float imageHeight = (float)this.getHeight();  
    float imageWidth = (float)this.getWidth();  
    float scaleFactor = Math.min((float)pageWidth/(float)imageWidth, (float)pageHeight/(float)imageHeight);  
    int scaledWidth = (int)(((float)imageWidth)*scaleFactor);  
    int scaledHeight = (int)(((float)imageHeight)*scaleFactor);    
    BufferedImage canvas = new BufferedImage( this.getWidth(),  this.getHeight(), BufferedImage.TYPE_INT_RGB);  
    Graphics2D gg = canvas.createGraphics();  
    this.paint( gg );    
    Image img = canvas ;  
    g2d.drawImage(img, 0, 0, scaledWidth, scaledHeight, null );  
    return Printable.PAGE_EXISTS;  
}  
private void button4ActionPerformed() {
    // TODO add your code
    PrinterJob job = PrinterJob.getPrinterJob();
    job.setPrintable(this);
    boolean ok = job.printDialog();
    if (ok) {
        try {
             job.print();
        } catch (PrinterException ex) {
            System.out.println("Error printing: " + ex);
         /* The job did not successfully complete */
        }
    }
}

我还需要隐藏一些按钮和文本字段不打印。（例如："打印"按钮）任何帮助将不胜感激。

Answer 1

而不是this.paint( gg );调用componentInTheScrollPane.paint(gg); 。最好打电话给printAll(gg);

Answer 2

如果您尝试将jScrollPane绘制到图像上，则每次都会失败，并且仅打印可见部分。要解决此问题，您需要绘制jScrollPane的内容，理想情况下，您将在jScrollPane中拥有一个jLayer，jPanel或其他容器，并且可以将其直接绘制到图像上，如下所示：

Form (jPanel top container)
 -> jScrollPane
     -> jLayer/jPanel/container
         -> Contents (tables, buttons etc)  

我不会给你关于如何使用整个scrollPane打印整个表单的代码，这需要一些数学和更多的代码，但为了让你从这里开始，这里有一个示例方法，它将jLayer的内容绘制到缓冲图像，无论它是否在jScrollPane中不可见， 然后将该图像保存到文件：（我不会涵盖打印，这是另一个问题）

private void button4ActionPerformed() {
    try
    {
        //get height/width from the jLayeredPane or jPanel inside the scroll pane
        int imageHeight = jLayeredPane.getHeight();
        int imageWidth = jLayeredPane.getWidth();
        //Draw contents of the jLayeredPane or jPanel inside the scroll pane (but not the scroll pane itself)
        BufferedImage image = new BufferedImage(imageWidth, imageHeight, BufferedImage.TYPE_INT_RGB);  
        Graphics2D gg = image.createGraphics();  
        jLayeredPane.paint(gg);
        //The "image" now has jLayers contents
        //Insert your code here to scale and print the image here
        //Some Code
        //In my example I have chosen to save the image to file with no scaling
        ImageIO.write(canvas, "png", new File("C:\out.png"));
        //Some Code
        System.out.println("Done");
    }
    catch (IOException ex)
    {
        Logger.getLogger(GUI.class.getName()).log(Level.SEVERE, null, ex);
    }
}