我想在未修饰的JFrame周围添加一个阴影边框。我在stackoverflow上找到了这个：Undecorated JFrame shadow
然而，当我将JFrame背景颜色设置为半透明时，这会导致我的框架中的重量级组件出现问题known issue。
还有其他方法可以实现吗？我想我的JFrames需要一个特殊的LAF，它没有标题区域，没有窗口边框，但我没有写LAF的经验。
JxBrowser是我的示例中的重量级组件，呈现透明。他们有一个选项，可以在轻量级渲染模式下渲染，但我的内存和CPU飙升并且是不可接受的。应该有另一种方法在我未修饰的jframe周围绘制阴影边框。
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Insets;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.awt.image.ConvolveOp;
import java.awt.image.Kernel;
import java.util.HashMap;
import java.util.Map;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.Border;
import com.teamdev.jxbrowser.chromium.Browser;
import com.teamdev.jxbrowser.chromium.swing.BrowserView;
public class ShadowWindowBrowser {
private static enum Position {
TOP, TOP_LEFT, LEFT, BOTTOM_LEFT, BOTTOM, BOTTOM_RIGHT, RIGHT, TOP_RIGHT
};
private static final Map<Integer, Map<Position, BufferedImage>> CACHE = new HashMap<Integer, Map<Position, BufferedImage>>();
public static void main(String[] args) {
new ShadowWindowBrowser();
}
public ShadowWindowBrowser() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setUndecorated(true);
frame.setBackground(new Color(0, 0, 0, 0));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(new ShadowPane());
Browser browser = new Browser();
BrowserView browserView = new BrowserView(browser);
browser.loadURL("http://google.com");
JPanel panel = new JPanel(new BorderLayout());
panel.add(browserView, BorderLayout.CENTER);
frame.add(panel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class ShadowPane extends JPanel {
private Border dropShadowBorder = new DropShadowBorder(UIManager.getColor("Control"), 1, 5, .5f, 12, true, true, true, true);
public ShadowPane() {
setLayout(new BorderLayout());
setOpaque(false);
setBackground(Color.BLACK);
setBorder(dropShadowBorder);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(500, 500);
}
}
class DropShadowBorder implements Border {
private Color lineColor;
private int lineWidth;
private int shadowSize;
private float shadowOpacity;
private int cornerSize;
private boolean showTopShadow;
private boolean showLeftShadow;
private boolean showBottomShadow;
private boolean showRightShadow;
public DropShadowBorder() {
this(UIManager.getColor("Control"), 1, 5);
}
public DropShadowBorder(Color lineColor, int lineWidth, int shadowSize) {
this(lineColor, lineWidth, shadowSize, .5f, 12, false, false, true, true);
}
public DropShadowBorder(Color lineColor, int lineWidth, boolean showLeftShadow) {
this(lineColor, lineWidth, 5, .5f, 12, false, showLeftShadow, true, true);
}
public DropShadowBorder(Color lineColor, int lineWidth, int shadowSize, float shadowOpacity, int cornerSize,
boolean showTopShadow, boolean showLeftShadow, boolean showBottomShadow, boolean showRightShadow) {
this.lineColor = lineColor;
this.lineWidth = lineWidth;
this.shadowSize = shadowSize;
this.shadowOpacity = shadowOpacity;
this.cornerSize = cornerSize;
this.showTopShadow = showTopShadow;
this.showLeftShadow = showLeftShadow;
this.showBottomShadow = showBottomShadow;
this.showRightShadow = showRightShadow;
}
/**
* @inheritDoc
*/
@Override
public void paintBorder(Component c, Graphics graphics, int x, int y, int width, int height) {
/*
* 1) Get images for this border 2) Paint the images for each side of
* the border that should be painted
*/
Map<Position, BufferedImage> images = getImages(null);
// compute the edges of the component -- not including the border
Insets borderInsets = getBorderInsets(c);
int leftEdge = x + borderInsets.left - lineWidth;
int rightEdge = x + width - borderInsets.right;
int topEdge = y + borderInsets.top - lineWidth;
int bottomEdge = y + height - borderInsets.bottom;
Graphics2D g2 = (Graphics2D) graphics;
g2.setColor(lineColor);
// The location and size of the shadows depends on which shadows are
// being
// drawn. For instance, if the left & bottom shadows are being drawn,
// then
// the left shadow extends all the way down to the corner, a corner is
// drawn,
// and then the bottom shadow begins at the corner. If, however, only
// the
// bottom shadow is drawn, then the bottom-left corner is drawn to the
// right of the corner, and the bottom shadow is somewhat shorter than
// before.
Point topLeftShadowPoint = null;
if (showLeftShadow || showTopShadow) {
topLeftShadowPoint = new Point();
if (showLeftShadow && !showTopShadow) {
topLeftShadowPoint.setLocation(x, y + shadowSize);
} else if (showLeftShadow && showTopShadow) {
topLeftShadowPoint.setLocation(x, y);
} else if (!showLeftShadow && showTopShadow) {
topLeftShadowPoint.setLocation(x + shadowSize, y);
}
}
Point bottomLeftShadowPoint = null;
if (showLeftShadow || showBottomShadow) {
bottomLeftShadowPoint = new Point();
if (showLeftShadow && !showBottomShadow) {
bottomLeftShadowPoint.setLocation(x, y + height - shadowSize - shadowSize);
} else if (showLeftShadow && showBottomShadow) {
bottomLeftShadowPoint.setLocation(x, y + height - shadowSize);
} else if (!showLeftShadow && showBottomShadow) {
bottomLeftShadowPoint.setLocation(x + shadowSize, y + height - shadowSize);
}
}
Point bottomRightShadowPoint = null;
if (showRightShadow || showBottomShadow) {
bottomRightShadowPoint = new Point();
if (showRightShadow && !showBottomShadow) {
bottomRightShadowPoint.setLocation(x + width - shadowSize, y + height - shadowSize - shadowSize);
} else if (showRightShadow && showBottomShadow) {
bottomRightShadowPoint.setLocation(x + width - shadowSize, y + height - shadowSize);
} else if (!showRightShadow && showBottomShadow) {
bottomRightShadowPoint.setLocation(x + width - shadowSize - shadowSize, y + height - shadowSize);
}
}
Point topRightShadowPoint = null;
if (showRightShadow || showTopShadow) {
topRightShadowPoint = new Point();
if (showRightShadow && !showTopShadow) {
topRightShadowPoint.setLocation(x + width - shadowSize, y + shadowSize);
} else if (showRightShadow && showTopShadow) {
topRightShadowPoint.setLocation(x + width - shadowSize, y);
} else if (!showRightShadow && showTopShadow) {
topRightShadowPoint.setLocation(x + width - shadowSize - shadowSize, y);
}
}
if (showLeftShadow) {
Rectangle leftShadowRect = new Rectangle(x, (int) (topLeftShadowPoint.getY() + shadowSize), shadowSize,
(int) (bottomLeftShadowPoint.getY() - topLeftShadowPoint.getY() - shadowSize));
g2.drawImage(images.get(Position.LEFT).getScaledInstance(leftShadowRect.width, leftShadowRect.height,
Image.SCALE_FAST), leftShadowRect.x, leftShadowRect.y, null);
}
if (showBottomShadow) {
Rectangle bottomShadowRect = new Rectangle((int) (bottomLeftShadowPoint.getX() + shadowSize),
y + height - shadowSize,
(int) (bottomRightShadowPoint.getX() - bottomLeftShadowPoint.getX() - shadowSize), shadowSize);
g2.drawImage(images.get(Position.BOTTOM).getScaledInstance(bottomShadowRect.width, bottomShadowRect.height,
Image.SCALE_FAST), bottomShadowRect.x, bottomShadowRect.y, null);
}
if (showRightShadow) {
Rectangle rightShadowRect = new Rectangle(x + width - shadowSize,
(int) (topRightShadowPoint.getY() + shadowSize), shadowSize,
(int) (bottomRightShadowPoint.getY() - topRightShadowPoint.getY() - shadowSize));
g2.drawImage(images.get(Position.RIGHT).getScaledInstance(rightShadowRect.width, rightShadowRect.height,
Image.SCALE_FAST), rightShadowRect.x, rightShadowRect.y, null);
}
if (showTopShadow) {
Rectangle topShadowRect = new Rectangle((int) topLeftShadowPoint.getX() + shadowSize, y,
(int) (topRightShadowPoint.getX() - topLeftShadowPoint.getX() - shadowSize), shadowSize);
g2.drawImage(images.get(Position.TOP).getScaledInstance(topShadowRect.width, topShadowRect.height,
Image.SCALE_FAST), topShadowRect.x, topShadowRect.y, null);
}
if (showLeftShadow || showTopShadow) {
g2.drawImage(images.get(Position.TOP_LEFT), null, (int) topLeftShadowPoint.getX(),
(int) topLeftShadowPoint.getY());
}
if (showLeftShadow || showBottomShadow) {
g2.drawImage(images.get(Position.BOTTOM_LEFT), null, (int) bottomLeftShadowPoint.getX(),
(int) bottomLeftShadowPoint.getY());
}
if (showRightShadow || showBottomShadow) {
g2.drawImage(images.get(Position.BOTTOM_RIGHT), null, (int) bottomRightShadowPoint.getX(),
(int) bottomRightShadowPoint.getY());
}
if (showRightShadow || showTopShadow) {
g2.drawImage(images.get(Position.TOP_RIGHT), null, (int) topRightShadowPoint.getX(),
(int) topRightShadowPoint.getY());
}
}
private Map<Position, BufferedImage> getImages(Graphics2D g2) {
// first, check to see if an image for this size has already been
// rendered
// if so, use the cache. Else, draw and save
Map<Position, BufferedImage> images = CACHE.get(shadowSize);
if (images == null) {
images = new HashMap<Position, BufferedImage>();
/*
* Do draw a drop shadow, I have to: 1) Create a rounded rectangle
* 2) Create a BufferedImage to draw the rounded rect in 3)
* Translate the graphics for the image, so that the rectangle is
* centered in the drawn space. The border around the rectangle
* needs to be shadowWidth wide, so that there is space for the
* shadow to be drawn. 4) Draw the rounded rect as black, with an
* opacity of 50% 5) Create the BLUR_KERNEL 6) Blur the image 7)
* copy off the corners, sides, etc into images to be used for
* drawing the Border
*/
int rectWidth = cornerSize + 1;
RoundRectangle2D rect = new RoundRectangle2D.Double(0, 0, rectWidth, rectWidth, cornerSize, cornerSize);
int imageWidth = rectWidth + shadowSize * 2;
BufferedImage image = new BufferedImage(imageWidth, imageWidth, BufferedImage.TYPE_INT_ARGB);
Graphics2D buffer = (Graphics2D) image.getGraphics();
buffer.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
buffer.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
buffer.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
buffer.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON);
buffer.setColor(new Color(0.0f, 0.0f, 0.0f, shadowOpacity));
buffer.translate(shadowSize, shadowSize);
buffer.fill(rect);
float blurry = 1.0f / (shadowSize * shadowSize);
float[] blurKernel = new float[shadowSize * shadowSize];
for (int i = 0; i < blurKernel.length; i++) {
blurKernel[i] = blurry;
}
ConvolveOp blur = new ConvolveOp(new Kernel(shadowSize, shadowSize, blurKernel));
BufferedImage targetImage = new BufferedImage(imageWidth, imageWidth, BufferedImage.TYPE_INT_ARGB);
((Graphics2D) targetImage.getGraphics()).drawImage(image, blur, -(shadowSize / 2), -(shadowSize / 2));
int x = 1;
int y = 1;
int w = shadowSize;
int h = shadowSize;
images.put(Position.TOP_LEFT, targetImage.getSubimage(x, y, w, h));
x = 1;
y = h;
w = shadowSize;
h = 1;
images.put(Position.LEFT, targetImage.getSubimage(x, y, w, h));
x = 1;
y = rectWidth;
w = shadowSize;
h = shadowSize;
images.put(Position.BOTTOM_LEFT, targetImage.getSubimage(x, y, w, h));
x = cornerSize + 1;
y = rectWidth;
w = 1;
h = shadowSize;
images.put(Position.BOTTOM, targetImage.getSubimage(x, y, w, h));
x = rectWidth;
y = x;
w = shadowSize;
h = shadowSize;
images.put(Position.BOTTOM_RIGHT, targetImage.getSubimage(x, y, w, h));
x = rectWidth;
y = cornerSize + 1;
w = shadowSize;
h = 1;
images.put(Position.RIGHT, targetImage.getSubimage(x, y, w, h));
x = rectWidth;
y = 1;
w = shadowSize;
h = shadowSize;
images.put(Position.TOP_RIGHT, targetImage.getSubimage(x, y, w, h));
x = shadowSize;
y = 1;
w = 1;
h = shadowSize;
images.put(Position.TOP, targetImage.getSubimage(x, y, w, h));
buffer.dispose();
image.flush();
}
return images;
}
/**
* @inheritDoc
*/
@Override
public Insets getBorderInsets(Component c) {
int top = showTopShadow ? lineWidth + shadowSize : lineWidth;
int left = showLeftShadow ? lineWidth + shadowSize : lineWidth;
int bottom = showBottomShadow ? lineWidth + shadowSize : lineWidth;
int right = showRightShadow ? lineWidth + shadowSize : lineWidth;
return new Insets(top - 1, left - 1, bottom - 1, right - 1);
}
/**
* @inheritDoc
*/
@Override
public boolean isBorderOpaque() {
return true;
}
public boolean isShowTopShadow() {
return showTopShadow;
}
public boolean isShowLeftShadow() {
return showLeftShadow;
}
public boolean isShowRightShadow() {
return showRightShadow;
}
public boolean isShowBottomShadow() {
return showBottomShadow;
}
public int getLineWidth() {
return lineWidth;
}
public Color getLineColor() {
return lineColor;
}
public int getShadowSize() {
return shadowSize;
}
public float getShadowOpacity() {
return shadowOpacity;
}
public int getCornerSize() {
return cornerSize;
}
}
}