我想在表示音频播放器(即播放过程)的JSlider后面放置一个图像(音频的可视化)。
首先,我尝试覆盖Slider的绘画方法
public void paintComponent(Graphics g) {
// Draw the previously loaded image to Component
g.drawImage(img, 0, -100, null);
super.paintComponent(g);
}
这行得通,但是图像比滑块高,所以我的下一个尝试是JLayeredPane,我将JSlider放在带有图像的JLabel上方。第一次看起来不错。但是我提到我需要滑块轨道后面的图像,而不是整个滑块。左右有空间。有人可以告诉我一种如何计算该空间的方法吗?还是轨道的宽度和与滑块边界的偏移量?它应该在Windows和MacOs下运行,所以外观和感觉不同,因此我认为硬编码值将不起作用。
Example Slider with background image
谢谢。
最佳答案
我针对此问题的解决方案现在是覆盖SliderUI。因此,这是一个非常特殊的组件,因此与所有LookAndFeels上的外观相同无关紧要。
它也支持直接跳到鼠标位置,这与BasicSliderUI不同。
/**
*
* Custom SliderUI for AudioPlayer with audioimage in background
*/
public class AudioSliderUI extends BasicSliderUI {
private BasicStroke stroke = new BasicStroke(1f, BasicStroke.CAP_ROUND,
BasicStroke.JOIN_ROUND, 0f);
public AudioSliderUI(AudioSlider b) {
super(b);
}
@Override
public void paint(Graphics g, JComponent c) {
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
super.paint(g, c);
}
@Override
protected Dimension getThumbSize() {
return new Dimension(2, 200);
}
@Override
public void paintTrack(Graphics g) {
Graphics2D g2d = (Graphics2D) g;
Stroke old = g2d.getStroke();
g2d.setStroke(stroke);
g2d.setPaint(Color.WHITE);
if (slider.getOrientation() == SwingConstants.HORIZONTAL) {
g2d.drawLine(trackRect.x, trackRect.y + trackRect.height / 2,
trackRect.x + trackRect.width, trackRect.y + trackRect.height / 2);
} else {
g2d.drawLine(trackRect.x + trackRect.width / 2, trackRect.y,
trackRect.x + trackRect.width / 2, trackRect.y + trackRect.height);
}
g2d.setStroke(old);
Image img = ((AudioSlider)slider).getImage();
g2d.drawImage(img, trackRect.x, trackRect.y, trackRect.width, trackRect.height, slider);
}
@Override
public void paintThumb(Graphics g) {
Rectangle knobBounds = thumbRect;
int w = knobBounds.width;
int h = 100;
int newStarty = knobBounds.height/2- h/2;
g.translate(knobBounds.x, knobBounds.y);
// "plain" version
g.setColor(Color.YELLOW);
g.fillRect(0, newStarty, w, h);
}
@Override
protected TrackListener createTrackListener(JSlider slider) {
return new TrackListener() {
@Override
public void mousePressed(MouseEvent e) {
if (UIManager.getBoolean("Slider.onlyLeftMouseButtonDrag")
&& SwingUtilities.isLeftMouseButton(e)) {
JSlider slider = (JSlider) e.getComponent();
switch (slider.getOrientation()) {
case SwingConstants.VERTICAL:
slider.setValue(valueForYPosition(e.getY()));
break;
case SwingConstants.HORIZONTAL:
slider.setValue(valueForXPosition(e.getX()));
break;
default:
throw new IllegalArgumentException(
"orientation must be one of: VERTICAL, HORIZONTAL");
}
super.mousePressed(e); // isDragging = true;
super.mouseDragged(e);
} else {
super.mousePressed(e);
}
}
@Override
public boolean shouldScroll(int direction) {
return false;
}
};
}
}
匹配滑块:
public class AudioSlider extends JSlider {
private Image img;
public AudioSlider() {
setOpaque(false);
}
/**
* @return the img
*/
public Image getImage() {
return img;
}
public void setImage(Image img) {
this.img = img;
}
}
为我工作,也许不能涵盖所有潜在客户。