TITLE:Borderのアニメーション

Borderのアニメーション

編集者:Terai Atsuhiro
作成日:2006-05-29
更新日:2021-06-25 (金) 22:29:08

概要

Borderの描画をアニメーションさせます。

#screenshot

サンプルコード

class RippleBorder extends EmptyBorder {
  private final javax.swing.Timer animator;
  private final JComponent comp;
  public RippleBorder(JComponent c, int width) {
    super(width, width, width, width);
    this.comp = c;
    animator = new javax.swing.Timer(80, new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        comp.repaint();
        count+=0.9f;
      }
    });
    comp.addMouseListener(new MouseAdapter() {
      public void mouseEntered(MouseEvent e) {
        comp.setForeground(Color.red);
        startAnimation();
      }
      public void mouseExited(MouseEvent e) {
        comp.setForeground(Color.black);
        stopAnimation();
      }
    });
  }
  boolean startflag = false;
  boolean stopflag  = false;
  public void startAnimation() {
    startflag = true;
    stopflag = false;
    animator.start();
  }
  public void stopAnimation() {
    stopflag = true;
  }
  private float count = 1.0f;
  public void paintBorder(Component c, Graphics g,
                          int x, int y, int w, int h) {
    if(!startflag) return;
    Graphics2D g2 = (Graphics2D)g;
    g2.setColor(Color.white);
    float a = 1.0f/count;
    if(0.12f-a>1.0e-2) a = 0.0f;
    g2.setComposite(
      AlphaComposite.getInstance(AlphaComposite.SRC_OVER,a));
    Insets i = getBorderInsets();
    int xx = i.left-(int)count;
    int yy = i.top-(int)count;
    int ww = i.left+i.right-(int)(count*2.0f);
    int hh = i.top+i.bottom-(int)(count*2.0f);
    g2.setStroke(new BasicStroke(count*1.2f));
    g2.drawRoundRect(xx, yy, w-ww, h-hh, 10, 10);
    if(xx<0) {
      count = 1.0f;
      if(stopflag) {
        animator.stop();
        startflag = false;
        stopflag = false;
        return;
      }
    }
  }
}
  • &jnlp;
  • &jar;
  • &zip;

解説

コンポーネント上にカーソルがきた場合、Borderをアニメーションさせることで、波紋状の効果を描画しています。

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