着是全部代码 class FontPanelTest extends JPanel { public void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2 = (Graphics2D) g; String message = "Hello, World!"; Font f = new Font("Serif", Font.BOLD, 36); g2.setFont(f); // measure the size of the message FontRenderContext context = g2.getFontRenderContext(); Rectangle2D bounds = f.getStringBounds(message, context); // set (x,y) = top left corner of text double x = (getWidth() - bounds.getWidth()) / 2; double y = (getHeight() - bounds.getHeight()) / 2; // add ascent to y to reach the baseline double ascent = -bounds.getY(); double baseY = y + ascent; // draw the message g2.drawString(message, (int) x, (int) baseY); g2.setPaint(Color.GRAY); // draw the baseline g2.draw(new Line2D.Double(x, baseY, x + bounds.getWidth(), baseY)); // draw the enclosing rectangle Rectangle2D rect = new Rectangle2D.Double(x, y, bounds.getWidth(), bounds.getHeight()); g2.draw(rect); } }
让字符串居中显示并绘制字符串基线和包括字符串的矩形 但问题是 Rectangle2D rect = new Rectangle2D.Double(x, y, bounds.getWidth(), bounds.getHeight());中的x,y是矩形的左上角坐标吗真分明不是左下角坐标啊
class FontPanelTest extends JPanel
{
public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g; String message = "Hello, World!"; Font f = new Font("Serif", Font.BOLD, 36);
g2.setFont(f); // measure the size of the message FontRenderContext context = g2.getFontRenderContext();
Rectangle2D bounds = f.getStringBounds(message, context); // set (x,y) = top left corner of text double x = (getWidth() - bounds.getWidth()) / 2;
double y = (getHeight() - bounds.getHeight()) / 2; // add ascent to y to reach the baseline double ascent = -bounds.getY();
double baseY = y + ascent; // draw the message g2.drawString(message, (int) x, (int) baseY); g2.setPaint(Color.GRAY); // draw the baseline g2.draw(new Line2D.Double(x, baseY, x + bounds.getWidth(), baseY)); // draw the enclosing rectangle Rectangle2D rect = new Rectangle2D.Double(x, y, bounds.getWidth(), bounds.getHeight());
g2.draw(rect);
}
}
但问题是 Rectangle2D rect = new Rectangle2D.Double(x, y, bounds.getWidth(), bounds.getHeight());中的x,y是矩形的左上角坐标吗真分明不是左下角坐标啊