Question

我正在尝试将JFrame上显示的光标更改为某些文本，例如“等待请完成您的工作”，而某个button的{{1}}方法正在执行。我之前找到的唯一解决方案是使用包含所需文本的actionPerformed()更改Cursor。代码如下：

Image

此代码的问题是import java.awt.BorderLayout; import java.awt.Color; import java.awt.Cursor; import java.awt.Dimension; import java.awt.Graphics2D; import java.awt.Point; import java.awt.Toolkit; import java.awt.event.ActionEvent; import java.awt.geom.Ellipse2D; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import java.nio.file.Paths; import javax.imageio.ImageIO; import javax.swing.AbstractAction; import javax.swing.JButton; import javax.swing.JFrame; public class Hasikome extends JFrame{ static Cursor cursor; private static final long serialVersionUID = 1L; public static void main(String[] args) { final Hasikome hasi = new Hasikome(); hasi.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); hasi.setSize(new Dimension(1200, 1200)); hasi.setPreferredSize(new Dimension(500, 500)); Toolkit kit = Toolkit.getDefaultToolkit(); Dimension dim = kit.getBestCursorSize(16, 16); BufferedImage buffered = null; try { buffered = ImageIO.read(new File(Paths.get("").toAbsolutePath().toString() + "\\belge.png")); } catch (IOException e) { e.printStackTrace(); } java.awt.Shape circle = new Ellipse2D.Float(0, 0, dim.width - 1, dim.height - 1); Graphics2D g = buffered.createGraphics(); g.setColor(Color.BLUE); g.draw(circle); g.setColor(Color.RED); hasi.add(new JButton(new AbstractAction() { private static final long serialVersionUID = 1L; @Override public void actionPerformed(ActionEvent e) { hasi.setCursor(cursor); try { Thread.sleep(10000); } catch (InterruptedException e1) { e1.printStackTrace(); } finally { hasi.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR)); } } }), BorderLayout.NORTH); int centerX = (dim.width - 1) /2; int centerY = (dim.height - 1) / 2; g.drawLine(centerX, 0, centerX, dim.height - 1); g.drawLine(0, centerY, dim.height - 1, centerY); g.dispose(); cursor = kit.createCustomCursor(buffered, new Point(centerX, centerY), "myCursor"); hasi.pack(); hasi.setVisible(true); } }此行始终在Dimension dim = kit.getBestCursorSize(16, 16);上生成大小为32x32的Cursor，并且与平台有关。我不能使用超过32x32的值，否则我会对行Windows获得异常。因为我使用了相当长的文本（250x16），所以我无法正确地将cursor = kit.createCustomCursor(buffered, new Point(centerX, centerY), "myCursor");显示为text image。

此解决方案不是必需的，我想要完成的是在执行某些Cursor的{{1}}方法时向用户显示文本Cursor。有什么方法可以做到这一点吗？提前谢谢。

Answer 1

查看Disabled Glass Pane一种方法。

如果允许您使用＆＃34;等待＆＃34;在半透明背景上显示带有文字的Glass Pane。光标。

Answer 2

除非你绝对必须使用文字＆＃34;请等待，＆＃34;您可以更轻松地使用计算机内置的加载图标。如果您使用：

hasi.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
doProcessing();
hasi.setCursor(Cursor.getDefaultCursor());

它应该具有相同的效果。

Answer 3

您是否要阻止UI线程？

在任何情况下，最好的方法可能是使用JLayeredPane，在JLayeredPane的模态层上弹出一个JLabel（您需要自己设置它的大小），然后在作业完成时将其删除。

Answer 4

这不是答案，但也许可以做你想做的事：

package com.stackoverflow.questions;

import java.awt.Color;
import java.awt.Cursor;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import javax.swing.SwingWorker;

/**
 * Just an idea for the Stackoverflow question http://stackoverflow.com/questions/27822671
 */
public class SO27822671 extends JFrame {

  /**
   * The Glasspane on which we'll draw the "please wait..." thing.
   */
  private MyGlassPane myGlassPane;

  /**
   * Blank cursor to hide the cursor.
   */
  private final Cursor blankCursor;

  /**
   * Init.
   */
  public SO27822671() {
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setBounds(300, 300, 400, 400);

    myGlassPane = new MyGlassPane();
    setGlassPane(myGlassPane);

    getContentPane().setLayout(new FlowLayout());
    getContentPane().add(new JButton(new AbstractAction("Click Me!") {

      @Override
      public void actionPerformed(ActionEvent e) {
        doMyStuff();
      }
    }));

    // http://stackoverflow.com/a/1984117/3366578
    blankCursor = Toolkit.getDefaultToolkit().createCustomCursor(
        new BufferedImage(16, 16, BufferedImage.TYPE_INT_ARGB), new Point(0, 0), "blank cursor");
  }

  /**
   * Do the heavy stuff.
   */
  private void doMyStuff() {
    // show our glasspane
    myGlassPane.setVisible(true);

    // save the current cursor
    final Cursor currentCursor = getCursor();

    // hide the cursor
    setCursor(blankCursor);

    new SwingWorker<Void, Void>() {

      @Override
      protected Void doInBackground() throws Exception {
        // hard work here
        Thread.sleep(2000);
        return null;
      }

      @Override
      protected void done() {
        try {
          get();
        }
        catch (Exception e) {
          // do your exception handling here
          e.printStackTrace();
        }
        finally {
          // hide our glasspane
          myGlassPane.setVisible(false);

          // restore the cursor
          setCursor(currentCursor);
        }
      }
    }.execute();
  }

  /**
   * This is our glasspane.
   */
  class MyGlassPane extends JComponent {

    /**
     * To save the mouse X position.
     */
    private int mouseXPosition;

    /**
     * To save the mouse Y position.
     */
    private int mouseYPosition;

    /**
     * The text to show.
     */
    private String text = "Please wait...";

    /**
     * Init.
     */
    public MyGlassPane() {
      // to get the cursor position
      MouseAdapter mouseAdapter = new MouseAdapter() {

        @Override
        public void mouseMoved(MouseEvent e) {
          computeMousePositionAndRepaint(e);
        }

        @Override
        public void mouseEntered(MouseEvent e) {
          computeMousePositionAndRepaint(e);
        }
      };

      addMouseMotionListener(mouseAdapter);
      addMouseListener(mouseAdapter);
    }

    /**
     * Compute the mouse position and invoke repaint on our glasspane.
     * @param e 
     */
    private void computeMousePositionAndRepaint(MouseEvent e) {
      mouseXPosition = e.getX();
      mouseYPosition = e.getY();
      repaint();
    }

    @Override
    protected void paintComponent(Graphics g) {
      // draw here what you want instead
      int textHeight = g.getFontMetrics().getHeight();
      int textWidth = g.getFontMetrics().stringWidth(text);
      int textDescent = g.getFontMetrics().getDescent();

      int x = mouseXPosition - textWidth / 2;
      int y = mouseYPosition - textHeight / 2;

      g.setColor(Color.white);
      g.fillRect(x - 4, y - 4, textWidth + 8, textHeight + 8);

      ((Graphics2D) g).setRenderingHint(
          RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
      g.setColor(Color.black);
      g.drawString(text, x, y + textHeight - textDescent);
    }
  }

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

      @Override
      public void run() {
        new SO27822671().setVisible(true);
      }
    });
  }
}

那是只是一个想法。

用文本更改/显示光标

4 个答案: