半透明 JButton：對像出現在背景中 (Semi-Transparent JButton: Objects appear in Background)

問題描述

半透明 JButton：對像出現在背景中 (Semi‑Transparent JButton: Objects appear in Background)

我遇到了一個問題：我開始製作一個更好看的 Swing‑JButton 擴展。剩下的問題之一：每當我將它設置為“半透明”（如 this.setBackground(new Color(100,100,100,90));）時，光學變得奇怪：每次我將鼠標懸停在我懸停的最後一個帶有字符串的 Swing‑Element 按鈕（如 JRadioButton 或 JCheckBox）將出現在背景中。

我當前的按鈕：

private boolean transparent;
private boolean drawImage;
private final int width;
private final int height;
int marginWidth=15;
int marginHeight=15;

public MyButton(String text, String command){
    super(text);
    this.setDoubleBuffered(true);
    this.setOpaque();
    this.setActionCommand(command);

    this.setBackground(ParameterPool.COLOR_BACKGROUND_SECOND);
    this.setBorder(null);

    this.width = (int) this.getPreferredSize().getWidth()+marginWidth;
    this.height = (int) this.getPreferredSize().getHeight()+marginHeight;

    this.setPreferredSize(new Dimension(this.width, this.height));

}


public void setTransparent() {
    this.transparent = true;
    this.setOpaque(false);
}

public void setOpaque() {
   this.transparent = false;
   this.setOpaque(true);
}
@Override
protected void paintComponent(Graphics g){
    Graphics2D g2d = (Graphics2D)g; 


    g2d.fillRoundRect(0,0,width,height,18,18); 

    g2d.setColor(Color.darkGray); 
    g2d.drawRoundRect(0,0,width, height,18,18); 

    FontRenderContext frc = new FontRenderContext(null, false, false); 
    Rectangle2D r = getFont().getStringBounds(getText(), frc);
    float xMargin = (float)(width‑r.getWidth())/2; 
    float yMargin = (float)(height‑getFont().getSize())/2; 
    g2d.drawString(getText(), xMargin, (float)getFont().getSize() + yMargin); 
    this.setSize(width, height);
}

public JPanel inTransparentPanel(){
    JPanel ret = new JPanel();
    ret.setOpaque(false);
    ret.setDoubleBuffered(true);
    ret.add(this);
    return ret;
}

還有一件事：我也試過這個，沒有覆蓋paintComponent(...)‑方法。沒有效果。

參考解法

方法 1:

Ok, just fixed this problem "by accident": I figured out that one of the Panels arround that buttons still was a java awt Pane. Never thought of that as a problem.

(by blackwodka86、blackwodka86)

參考文件

1. Semi‑Transparent JButton: Objects appear in Background (CC BY‑SA 2.5/3.0/4.0)