如何使 JButton 可见?
1) 当没有开启渐进式背景时:JButton 正在显示
2)当没有开启渐进背景时,按下JButton仍然没有闪烁:
3) 当渐进式背景打开时,JButton 是不可见的,按下时我看到闪烁,JButton() 出现并再次隐藏自动。 << 问题来了,我该如何解决?
import java.awt.Color;
import java.awt.AlphaComposite;
import java.awt.BorderLayout;
import java.awt.Graphics;
import javax.swing.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
public class ButtonTest extends JWindow implements MouseListener, MouseMotionListener {
private static final long serialVersionUID = 1L;
private JFrame frame = new JFrame();
private SoftJButton softButton1;
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
ButtonTest j = new ButtonTest();
j.createAndShowGUI();
}
});
}
public void createAndShowGUI() {
softButton1 = new SoftJButton("Transparent Button");
softButton1.setBackground(Color.GREEN);
softButton1.setAlpha(0.5f);
softButton1.setDoubleBuffered(true);
this.setLayout(new BorderLayout());
this.setBounds(100, 30, 200, 100);
this.setBackground(new Color(0, 0, 0, 255));
this.setVisible(true);
add(softButton1);
}
@Override
public void paint(Graphics g) {
super.paint(g);
}
public void mouseDragged(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
}
public void mouseMoved(MouseEvent e) {
}
public void mouseClicked(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public static class SoftJButton extends JButton {
private static final JButton lafDeterminer = new JButton();
private static final long serialVersionUID = 1L;
private boolean rectangularLAF;
private float alpha = 1f;
public SoftJButton() {
this(null, null);
}
public SoftJButton(String text) {
this(text, null);
}
public SoftJButton(String text, Icon icon) {
super(text, icon);
setOpaque(false);
setFocusPainted(false);
}
public float getAlpha() {
return alpha;
}
public void setAlpha(float alpha) {
this.alpha = alpha;
repaint();
}
@Override
public void paintComponent(java.awt.Graphics g) {
java.awt.Graphics2D g2 = (java.awt.Graphics2D) g;
g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha));
if (rectangularLAF && isBackgroundSet()) {
Color c = getBackground();
g2.setColor(c);
g.fillRect(0, 0, getWidth(), getHeight());
}
super.paintComponent(g2);
}
@Override
public void updateUI() {
super.updateUI();
lafDeterminer.updateUI();
rectangularLAF = lafDeterminer.isOpaque();
}
}
}
最佳答案
不清楚您的视频源是如何工作的,但由于 Mixing Heavyweight and Lightweight Components,它似乎与 Swing 不兼容。 .虽然 awt
组件不是透明的,但您始终可以在 Frame
上绘制自己的半透明文本并进行手动 HitTest ,如下所示。您还可以检查您的视频源 API 是否支持 Double Buffering and Page Flipping .
import java.awt.Color;
import java.awt.AlphaComposite;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.Rectangle;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.geom.Rectangle2D;
/** @see http://stackoverflow.com/questions/6725618 */
public class AlphaFrame extends Frame {
private static final Font font = new Font("Dialog", Font.BOLD, 24);
private float alpha = 1f;
private Rectangle rect = new Rectangle();
public static void main(String[] args) {
AlphaFrame af = new AlphaFrame();
af.setTitle("Translucent Button");
af.setAlpha(0.5f);
af.setForeground(Color.green);
af.setBackground(Color.black);
af.setVisible(true);
}
public AlphaFrame() {
this.setSize(320, 240);
this.setLocationRelativeTo(null);
this.setBackground(Color.white);
this.addWindowListener(new WindowAdapter() {
@Override
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
this.addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
if (rect.contains(e.getPoint())) {
System.out.println("Pressed.");
}
}
});
repaint();
}
@Override
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2 = (Graphics2D) g;
g2.setComposite(AlphaComposite.getInstance(
AlphaComposite.SRC_OVER, alpha));
g2.setColor(getForeground());
g2.setFont(font);
FontMetrics fm = g2.getFontMetrics();
String s = getTitle();
Insets i = getInsets();
int dx = i.left + 10;
int dy = i.top + fm.getHeight() + 10;
Rectangle2D bounds = fm.getStringBounds(s, g);
rect.x = dx + (int) bounds.getX() - 1;
rect.y = dy + (int) bounds.getY() - 1;
rect.width = (int) bounds.getWidth() + 1;
rect.height = (int) bounds.getHeight() + 1;
System.out.println(i + " \n" + bounds + "\n" + rect);
g2.drawRect(rect.x, rect.y, rect.width, rect.height);
g2.drawString(s, dx, dy);
}
public float getAlpha() {
return alpha;
}
public void setAlpha(float alpha) {
this.alpha = alpha;
}
}
关于java - 我怎样才能使这个 JButton 可见?当我有逐行扫描背景 JWindow() 时?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/6725618/