Java中全透明窗口的形状刷新

Question

这是我的第一个问题，因为到目前为止我可以通过其他问题找到任何内容。我的问题来了： 我设计了一个窗户，上面有两个部分。左侧部分是完全透明的，我想在其上绘制一个可刷新的形状。 （在下文中，形状是正方形。）右侧部分始终是不透明的，我不会在其上绘制任何形状。一切正常，但对于左侧部分，背景形状不可刷新。

        package haxbot;

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

    // import com.sun.awt.AWTUtilities;
    public class drawScreen extends javax.swing.JFrame {

        public drawScreen() {
            initComponents();
        }
    //-------------------- automatically created ---------------------------------
        // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
        private void initComponents() {

            jLabel1 = new javax.swing.JLabel();
            jLabel2 = new javax.swing.JLabel();
            jLabel5 = new javax.swing.JLabel();
            jLabel6 = new javax.swing.JLabel();
            jButton1 = new javax.swing.JButton();

            setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
            setAlwaysOnTop(true);
            setCursor(new java.awt.Cursor(java.awt.Cursor.DEFAULT_CURSOR));
            setResizable(false);
            setUndecorated(true);
            addMouseMotionListener(new java.awt.event.MouseMotionAdapter() {
                public void mouseMoved(java.awt.event.MouseEvent evt) {
                    formMouseMoved(evt);
                }
            });

            jLabel1.setText("Position:");

            jLabel2.setForeground(new java.awt.Color(255, 0, 0));
            jLabel2.setText("[ 123, 134]");

            jLabel5.setText("Color:");

            jLabel6.setForeground(new java.awt.Color(255, 0, 0));
            jLabel6.setText("[ 255, 255, 255]");

            jButton1.setBackground(new java.awt.Color(255, 0, 0));
            jButton1.setFont(new java.awt.Font("Tahoma", 1, 11)); // NOI18N
            jButton1.setForeground(new java.awt.Color(255, 0, 0));
            jButton1.setText("X");
            jButton1.addActionListener(new java.awt.event.ActionListener() {
                public void actionPerformed(java.awt.event.ActionEvent evt) {
                    jButton1ActionPerformed(evt);
                }
            });

            javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
            getContentPane().setLayout(layout);
            layout.setHorizontalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                    .addContainerGap(853, Short.MAX_VALUE)
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                            .addGroup(layout.createSequentialGroup()
                                .addComponent(jLabel1)
                                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                                .addComponent(jLabel2, javax.swing.GroupLayout.PREFERRED_SIZE, 88, javax.swing.GroupLayout.PREFERRED_SIZE))
                            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                                .addComponent(jLabel5, javax.swing.GroupLayout.PREFERRED_SIZE, 40, javax.swing.GroupLayout.PREFERRED_SIZE)
                                .addGap(26, 26, 26)
                                .addComponent(jLabel6, javax.swing.GroupLayout.PREFERRED_SIZE, 88, javax.swing.GroupLayout.PREFERRED_SIZE)))
                        .addComponent(jButton1, javax.swing.GroupLayout.Alignment.TRAILING)))
            );
            layout.setVerticalGroup(
                layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 15, javax.swing.GroupLayout.PREFERRED_SIZE)
                    .addGap(58, 58, 58)
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                        .addComponent(jLabel2)
                        .addComponent(jLabel1))
                    .addGap(18, 18, 18)
                    .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                        .addComponent(jLabel6)
                        .addComponent(jLabel5))
                    .addContainerGap(338, Short.MAX_VALUE))
            );

            pack();
        }// </editor-fold> 
//-------------------- automatically created (end) ---------------------------------                       

        private void formMouseMoved(java.awt.event.MouseEvent evt) {                                
            MousePos = evt.getPoint();
            int mX = (int) MousePos.getX();
            int mY = (int) MousePos.getY();
            MousePos = evt.getPoint();
            jLabel2.setText("[ " + mX + ", " + mY + " ]");
            getColor(mX + (int) wind.getLocation().getX(), mY + (int) wind.getLocation().getY());
            paint(this.getGraphics());
        }                               

        private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
            System.exit(0);
        }                                        

        public Color getColor(int mX, int mY) {
            try {
                robot = new Robot();
            } catch (AWTException awtE) {
                awtE.printStackTrace();
            }

            Rectangle captureSize = new Rectangle(mX - 15, mY - 15, 30, 30);
            img = robot.createScreenCapture(captureSize);

            currColor = robot.getPixelColor(mX, mY);


            for (int i = 0; i < img.getWidth(); i++) {
                for (int j = 0; j < img.getHeight(); j++) {
                    int x = img.getRGB(i, j);

                }
            }

            jLabel6.setText("[ " + currColor.getRed() + ", " + currColor.getGreen() + ", "
                    + currColor.getBlue() + "]");
            return currColor;
        }

        public static void main(String args[]) {
            graphicsObtained = false;
            java.awt.EventQueue.invokeLater(new Runnable() {

                public void run() {
                    wind = new drawScreen();
                    wind.setVisible(true);
                    wind.setLocation(182, 154);
                    wind.setDefaultCloseOperation(EXIT_ON_CLOSE);
                    try {
                        //UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
                        UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
                        SwingUtilities.updateComponentTreeUI(wind);
                    } catch (Exception ex) {
                        ex.printStackTrace();
                    }
                    // Add Transparency
                    //  AWTUtilities.setWindowOpacity(wind, (float) 0.6);
                    currColors = new Color[10][10];

                }
            });
        }

        public void paint(Graphics g) {
            leftScreen = (Graphics2D) g.create();
            leftScreen.setClip(0, 0, 840, 410);

            if (MousePos != null) {
                //leftScreen.clearRect((int) MousePos.getX() - 150, (int) MousePos.getY() - 150, 300, 300);
                leftScreen.drawRect((int) MousePos.getX() - 15, (int) MousePos.getY() - 15, 30, 30);
            }

            rightScreen = (Graphics2D) g.create();
            rightScreen.setClip(850, 0, this.getWidth(), 410);
            super.paint(rightScreen);
            rightScreen.dispose();
            leftScreen.dispose();
            if (MousePos != null) {
                //g2d1.clearRect(0, 0, 520, 430);
            }


            /*g2d.setColor(Color.red);
            g2d.clearRect(55, 430, 90, 10);
            if (MousePos != null)
            g2d.drawString("[ " + MousePos.getX() + ", " + MousePos.getY() + " ]", 55, 440);
            else
            g2d.drawString("[ 0, 0 ]", 55, 440);*/

        }
        // Variables declaration - do not modify                     
        private javax.swing.JButton jButton1;
        private javax.swing.JLabel jLabel1;
        private javax.swing.JLabel jLabel2;
        private javax.swing.JLabel jLabel5;
        private javax.swing.JLabel jLabel6;
        // End of variables declaration                   
        private Point MousePos;
        private Point PlayerPos;
        private Color currColor;
        private static Color[][] currColors;
        private static drawScreen wind;
        private BufferedImage img;
        private static boolean graphicsObtained;
        private Graphics initialSection;
        private Graphics2D leftScreen, rightScreen;
        Robot robot = null;
    }

---------------------- 编辑（第二个代码） ---------------------- --------------------

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

// 3) Now in your class (which extends JFrame)
public class JFrameTrial extends JFrame {

    public static void main(String[] args) {
        MousePos = new Point(0, 0);

        JFrameTrial jft = new JFrameTrial();
        jft.setDefaultCloseOperation(EXIT_ON_CLOSE);
        jft.setSize(300, 300);
        jft.setVisible(true);

    }

    public JFrameTrial() {
        /* 4) set the contentPane using setContentPane
        as the class you just created extending JComponent.*/
        jct = new JComponentTrial(150, 150);
        setContentPane(jct);

        addMouseMotionListener(new java.awt.event.MouseMotionAdapter() {
            public void mouseMoved(MouseEvent e) {
                MousePos = e.getPoint();
                getContentPane().repaint();
            }
        });
    }
    private JComponentTrial jct;
    private static Point MousePos;

    // 1) But what you have to do is create a class which extends JComponent.
    private class JComponentTrial extends JComponent {

        public JComponentTrial(int x, int y) {
            setSize(x, y);
        }

        // 2)There override the paintComponent() method with whatever you want to draw.
        @Override
        public void paintComponent(Graphics g) {
            Graphics gg = g.create();
            gg.setColor(Color.red);
            gg.drawRect((int) MousePos.getX() - 15,
                    (int) MousePos.getY() - 15, 30, 30);
            gg.dispose();
        }
    }
}

Answer 1

一些建议：

• 在扩展 JPanel 或 JComponent 的类中绘制，而不是 JFrame。
• 使用重写的paintComponent方法而不是paint方法进行绘制。
• PaintComponent 方法的第一行应该是对 super.paintComponent(g); 的调用
• ，不要处置在paintComponent（或paint）参数中传递给您的Graphics 对象。仅处理您自己创建的 Graphics 或 Graphics2D 对象。

Answer 2

对于 Swing，您需要重写 paintComponent() 而不是 paint()。您直接在顶层容器上绘图。考虑使用 JPanel。覆盖 JPanel 的 paintComponent。

编辑

阅读您的反馈后，我想您需要做的是以下事情：

首先，要记住一些要点：

1. JFrame 不是 JComponent 的子类。所以它没有paintComponent()。并且paint不应该与Swing一起使用。因此您需要做一些不同的事情。

2. 与所有顶级容器一样，JFrame 也定义了许多窗格，其顶部是 JRootPane。JRootPane 由 glass 组成窗格、内容窗格和分层窗格。通常我们所做的只是创建一个类，它扩展一个组件，例如 JPanel。在该类中，我们重写 paintComponent() 方法，这就是我们绘制事物的方式。然后我们只需将其添加到 JFrame 的内容窗格中。

但您需要做的是创建一个扩展JComponent 的类。用你想要绘制的任何东西覆盖paintComponent()方法。现在，在您的类（扩展 JFrame）中，使用 setContentPane 设置 contentPane 作为您刚刚创建的扩展 JComponent 的类。 setContentPane 的结构是

public void setContentPane(Container contentPane)

因此，您可以传递扩展 JComponent 的类的对象，因为 JComponent 是 Container 的子类。

您所做的只是在使用 getContentPane 后设置内容窗格的布局。但您还需要对其进行设置，以使其按照您希望的方式运行。通常我们不会这样做，因为我们直接使用add()将组件添加到内容窗格中。我希望这会起作用。