java - JTextPane 的坐标以在 Java 中制作屏幕截图

Question

我希望有人能帮助我，这就是我想做的。

我有一个 JTextPane，我想截取该特定 JTextPane 坐标和大小的屏幕截图，到目前为止，我可以使用 JTextPane 的大小截取屏幕截图，但我无法获取特定坐标，我的屏幕截图总是得到 ( 0,0) 坐标。

这是我的方法:

void capturaPantalla () 
{
    try
    {
        int x = txtCodigo.getX();
        int y = txtCodigo.getY();

        Rectangle areaCaptura = new Rectangle(x, y, txtCodigo.getWidth(), txtCodigo.getHeight());

        BufferedImage capturaPantalla = new Robot().createScreenCapture(areaCaptura);

        File ruta = new File("P:\\captura.png");

        ImageIO.write(capturaPantalla, "png", ruta);

        JOptionPane.showMessageDialog(null, "Codigo de barras guardado!");      
    }

    catch (IOException ioe) 
    {
        System.out.println(ioe);
    }     

    catch(AWTException ex)
    {
        System.out.println(ex);
    }
} 

Answer 1

当您调用 getX() 时和 getY()在任何 Swing 组件上，您都会得到 相对于组件容器而非屏幕的 x 和 y。相反，您需要组件相对于屏幕的位置，并通过 getLocationOnScreen() 获取基于该位置的位置。

Point p = txtCodigo.getLocationOnScreen();
int x = p.x;
int y = p.y;

根据 MadProgrammer 的评论，您可以简单地调用 printAll(Graphics g)在您的 txtCodigo 组件上，传入从适当大小的 BufferedImage 获得的 Graphics 对象并放弃使用 Robot。

Dimension d = txtCodigo.getSize();
BufferedImage img = new BufferedImage(d.width, d.height, BufferedImage.TYPE_INT_ARGB);
Graphics g = img.getGraphics();
txtCodigo.printAll(g);
g.dispose();
// use ImageIO to write BufferedImage to file

---

比较两种方法:

import java.awt.AWTException;
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.event.ActionEvent;
import java.awt.image.BufferedImage;
import java.util.Random;

import javax.swing.*;

@SuppressWarnings("serial")
public class RobotVsPrintAll extends JPanel {
   private static final int WORDS = 400;
   private JTextArea textArea = new JTextArea(20, 40);
   private JScrollPane scrollPane = new JScrollPane(textArea);
   private Random random = new Random();

   public RobotVsPrintAll() {
      StringBuilder sb = new StringBuilder();
      for (int i = 0; i < WORDS; i++) {
         int wordLength = random.nextInt(4) + 4;
         for (int j = 0; j < wordLength; j++) {
            char myChar = (char) (random.nextInt('z' - 'a' + 1) + 'a');
            sb.append(myChar);
         }
         sb.append(" ");
      }
      textArea.setText(sb.toString());

      textArea.setLineWrap(true);
      textArea.setWrapStyleWord(true);
      scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);

      JButton robot1Btn = new JButton(new Robot1Action("Robot 1"));
      JButton robot2Btn = new JButton(new Robot2Action("Robot 2"));
      JButton printAllBtn = new JButton(new PrintAllAction("Print All"));

      JPanel btnPanel = new JPanel();
      btnPanel.add(robot1Btn);
      btnPanel.add(robot2Btn);
      btnPanel.add(printAllBtn);

      setLayout(new BorderLayout());
      add(scrollPane, BorderLayout.CENTER);
      add(btnPanel, BorderLayout.PAGE_END);
   }

   private void displayImg(BufferedImage img) {
      ImageIcon icon = new ImageIcon(img);
      JOptionPane.showMessageDialog(this, icon, "Display Image", 
            JOptionPane.PLAIN_MESSAGE);
   }

   private class Robot1Action extends AbstractAction {
      public Robot1Action(String name) {
         super(name);
         int mnemonic = (int) name.charAt(0);
         putValue(MNEMONIC_KEY, mnemonic);
      }

      @Override
      public void actionPerformed(ActionEvent e) {
         try {
            Component comp = scrollPane.getViewport();
            Point p = comp.getLocationOnScreen();
            Dimension d = comp.getSize();

            Robot robot = new Robot();

            Rectangle screenRect = new Rectangle(p.x, p.y, d.width, d.height);
            BufferedImage img = robot.createScreenCapture(screenRect);
            displayImg(img);

         } catch (AWTException e1) {
            e1.printStackTrace();
         }

      }

   }

   private class Robot2Action extends AbstractAction {
      public Robot2Action(String name) {
         super(name);
         int mnemonic = (int) name.charAt(0);
         putValue(MNEMONIC_KEY, mnemonic);
      }

      @Override
      public void actionPerformed(ActionEvent e) {
         try {
            Component comp = textArea;
            Point p = comp.getLocationOnScreen();
            Dimension d = comp.getSize();

            Robot robot = new Robot();

            Rectangle screenRect = new Rectangle(p.x, p.y, d.width, d.height);
            BufferedImage img = robot.createScreenCapture(screenRect);
            displayImg(img);

         } catch (AWTException e1) {
            e1.printStackTrace();
         }

      }

   }

   private class PrintAllAction extends AbstractAction {
      public PrintAllAction(String name) {
         super(name);
         int mnemonic = (int) name.charAt(0);
         putValue(MNEMONIC_KEY, mnemonic);
      }

      public void actionPerformed(ActionEvent e) {
         Dimension d = textArea.getSize();
         BufferedImage img = new BufferedImage(d.width, d.height, BufferedImage.TYPE_INT_ARGB);
         Graphics g = img.getGraphics();
         textArea.printAll(g);
         g.dispose();
         displayImg(img);
      }
   }

   private static void createAndShowGui() {
      RobotVsPrintAll mainPanel = new RobotVsPrintAll();

      JFrame frame = new JFrame("Robot Vs PrintAll");
      frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationByPlatform(true);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            createAndShowGui();
         }
      });
   }
}

如果您使用 printAll 打印文本组件，您将获得整个文本组件，甚至是未显示在 JScrollPane 视口(viewport)中的部分。