EditableLabel.java 文件源码

private void computeDimensions(Graphics g, Font font, FontMetrics fm) {
    String s = text;
    FontRenderContext frc = ((Graphics2D) g).getFontRenderContext();
    width = fm.stringWidth(s);
    ascent = fm.getAscent();
    descent = fm.getDescent();
    int[] xs = new int[s.length()];
    int[] ys = new int[s.length()];
    for (int i = 0; i < xs.length; i++) {
        xs[i] = fm.stringWidth(s.substring(0, i + 1));
        TextLayout lay = new TextLayout(s.substring(i, i + 1), font, frc);
        Rectangle2D rect = lay.getBounds();
        int asc = (int) Math.ceil(-rect.getMinY());
        int desc = (int) Math.ceil(rect.getMaxY());
        if (asc < 0)
            asc = 0;
        if (asc > 0xFFFF)
            asc = 0xFFFF;
        if (desc < 0)
            desc = 0;
        if (desc > 0xFFFF)
            desc = 0xFFFF;
        ys[i] = (asc << 16) | desc;
    }
    charX = xs;
    charY = ys;
    dimsKnown = true;
}