为什么JFrame仍然不透明？

Question

我正在使用Java 6.

我希望以下代码可以显示透明窗口。但它仍然显示一个白色背景的正常窗口。为什么？我认为如果我隐藏所有窗格是合乎逻辑的，它应该给我一个透明的窗口。

package MaskingEffect;

import java.awt.EventQueue;

import javax.swing.JFrame;

public class GlassMaskTest {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                // TODO Auto-generated method stub
                GlassMaskFrame frame=new GlassMaskFrame();

                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.getContentPane().setVisible(false);
                frame.getLayeredPane().setVisible(false);
                frame.getRootPane().setVisible(false);
                frame.getGlassPane().setVisible(false);
                frame.setVisible(true);
                //AWTUtilities.setWindowOpacity(frame, 0.1f);

            }
        });

    }

}

这是GlassMaskFrame：

package MaskingEffect;

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics2D;

import javax.swing.JComponent;
import javax.swing.JFrame;

import com.sun.awt.AWTUtilities;
import com.sun.xml.internal.ws.api.server.Container;

public class GlassMaskFrame extends JFrame {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    public GlassMaskFrame() {

        this.setSize(new Dimension(500, 600));
    }

}

我还尝试了setBackground(new Color(0,0,0,0)) 4个窗格中的每个窗格。但仍然没有透明窗口。

我不想使用AWTUtilities.setWindowOpacity()方法。

这就是我得到的：

Answer 1

将画面的背景颜色设置为

<frame-name>.setBackground(new Color(0, 0, 0, 0));

并设置内容窗格的不透明度或您正在使用的任何内容......

<content-pane-name>.setOpaque(false);

这可能会成功......

Answer 2

public TransparentJFrame()
{
setTitle("Transparent JFrame Demo");
setSize(400,400);
setLayout(new GridBagLayout());
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
//For Java 1.7 or above
setOpacity(0.4f);
//For lower java versions
//com.sun.awt.AWTUtilities.setWindowOpacity(this,0.4f);
}

Answer 3

使用Java 7+，使用Java 6，您需要使用私有API com.sun.awt.AWTUtilities

为此，我编写了一个实用程序类，使其更易于使用。它使用反射来确定它是否可以实际调用，以防您使用的Java版本低于6u10

public static boolean supportsPerAlphaPixel() {

    boolean support = false;

    try {

        Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
        support = true;

    } catch (Exception exp) {
    }

    return support;

}

public static void setOpaque(Window window, boolean opaque) {

    try {

        Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
        if (awtUtilsClass != null) {

            Method method = awtUtilsClass.getMethod("setWindowOpaque", Window.class, boolean.class);
            method.invoke(null, window, opaque);

        }

    } catch (Exception exp) {
    }

}

public static void setOpacity(Window window, float opacity) {

    try {

        Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
        if (awtUtilsClass != null) {

            Method method = awtUtilsClass.getMethod("setWindowOpacity", Window.class, float.class);
            method.invoke(null, window, opacity);

        }

    } catch (Exception exp) {

        exp.printStackTrace();

    }

}

public static float getOpacity(Window window) {

    float opacity = 1f;
    try {

        Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
        if (awtUtilsClass != null) {

            Method method = awtUtilsClass.getMethod("getWindowOpacity", Window.class);
            Object value = method.invoke(null, window);
            if (value != null && value instanceof Float) {

                opacity = ((Float) value).floatValue();

            }

        }

    } catch (Exception exp) {

        exp.printStackTrace();

    }

    return opacity;

}

不透明

import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagLayout;
import java.awt.Window;
import java.lang.reflect.Method;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.LineBorder;

public class Test {

    public static void main(String[] args) {
        new Test();
    }

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setUndecorated(true);
                setOpaque(frame, false);
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setContentPane(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            setOpaque(false);
            setBorder(new LineBorder(Color.RED));
            setLayout(new GridBagLayout());
            add(new JLabel("Look no hands"));
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }

    }

    public static boolean supportsPerAlphaPixel() {

        boolean support = false;

        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            support = true;

        } catch (Exception exp) {
        }

        return support;

    }

    public static void setOpaque(Window window, boolean opaque) {

        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            if (awtUtilsClass != null) {

                Method method = awtUtilsClass.getMethod("setWindowOpaque", Window.class, boolean.class);
                method.invoke(null, window, opaque);

            }

        } catch (Exception exp) {
        }

    }

    public static void setOpacity(Window window, float opacity) {

        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            if (awtUtilsClass != null) {

                Method method = awtUtilsClass.getMethod("setWindowOpacity", Window.class, float.class);
                method.invoke(null, window, opacity);

            }

        } catch (Exception exp) {

            exp.printStackTrace();

        }

    }

    public static float getOpacity(Window window) {

        float opacity = 1f;
        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            if (awtUtilsClass != null) {

                Method method = awtUtilsClass.getMethod("getWindowOpacity", Window.class);
                Object value = method.invoke(null, window);
                if (value != null && value instanceof Float) {

                    opacity = ((Float) value).floatValue();

                }

            }

        } catch (Exception exp) {

            exp.printStackTrace();

        }

        return opacity;

    }

}

透明

import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.awt.Window;
import java.lang.reflect.Method;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class Test {

    public static void main(String[] args) {
        new Test();
    }

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setUndecorated(true);
                setOpacity(frame, 0.5f);
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setContentPane(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            setLayout(new GridBagLayout());
            add(new JLabel("Look no hands"));
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }

    }

    public static boolean supportsPerAlphaPixel() {

        boolean support = false;

        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            support = true;

        } catch (Exception exp) {
        }

        return support;

    }

    public static void setOpaque(Window window, boolean opaque) {

        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            if (awtUtilsClass != null) {

                Method method = awtUtilsClass.getMethod("setWindowOpaque", Window.class, boolean.class);
                method.invoke(null, window, opaque);

            }

        } catch (Exception exp) {
        }

    }

    public static void setOpacity(Window window, float opacity) {

        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            if (awtUtilsClass != null) {

                Method method = awtUtilsClass.getMethod("setWindowOpacity", Window.class, float.class);
                method.invoke(null, window, opacity);

            }

        } catch (Exception exp) {

            exp.printStackTrace();

        }

    }

    public static float getOpacity(Window window) {

        float opacity = 1f;
        try {

            Class<?> awtUtilsClass = Class.forName("com.sun.awt.AWTUtilities");
            if (awtUtilsClass != null) {

                Method method = awtUtilsClass.getMethod("getWindowOpacity", Window.class);
                Object value = method.invoke(null, window);
                if (value != null && value instanceof Float) {

                    opacity = ((Float) value).floatValue();

                }

            }

        } catch (Exception exp) {

            exp.printStackTrace();

        }

        return opacity;

    }

}

现在，在您全面了解框架之前已经无法使用＃34;这可以使它工作，但是，它可能不适用于所有平台（如MacOS），它需要你要使用能够提供框架边框的外观（例如金属），这并不是特别令人愉快......