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I have a desktop Java application i'm working on and have been using JDK 6 for development via IDE. I use the rendering hint VALUE_FRACTIONALMETRICS_ON along with other hints to better render text in JLabels. These hints work beautifully on JVM 1.6 but i've recently noticed that it seems to ignore the VALUE_FRACTIONALMETRICS_ON completely when I run the app with a JRE 1.7 Is there something i'm doing wrong here that makes Java 7 ignore these hints?

lblDate = new ATimeLabel(ATimeLabel.DATE_LETTERS) {
    private static final long serialVersionUID = 1L;

    @Override
    protected void paintComponent(Graphics g) {

        Graphics2D g2d = (Graphics2D) g;

        g2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
                RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
        g2d.setRenderingHint(RenderingHints.KEY_RENDERING,
                RenderingHints.VALUE_RENDER_QUALITY);
        g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                RenderingHints.VALUE_ANTIALIAS_ON);
        g2d.setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS,
                RenderingHints.VALUE_FRACTIONALMETRICS_ON);

        super.paintComponent(g2d);
    }
};

FRACTIONALMETRICS has the biggest noticeable visual effect on text so getting that to work is what i'm looking to do.

here is a screen shot comparison of what it looks like when I run the app from my IDE (Left) which uses Java 6 and when I double click the Jar file its self (Right) which uses my systems JRE, Java 7. (I also temporary added the red border to show that the paint method does work)

Any help would be very much appreciated.

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1 回答 1

3

一般不需要设置VALUE_FRACTIONALMETRICS_ON。尝试使用提供的桌面提示。您还可以仔细检查 FontRenderContext 中的 Swing 抗锯齿提示。示例用法如下所示。

如果您希望加粗文本，这是分数度量的副作用，我更喜欢使用粗体字体，或者将输出渲染为图像，并在绘图之前对其进行模糊处理。这将确保一个独立于系统的解决方案。

import java.awt.*;
import java.awt.event.*;
import java.util.Map;
import javax.swing.JLabel;

public class TextHints {
    public static void main(String[] args) {
        Frame frame = new Frame();
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
        JLabel label = new JLabel("Sunday, March 17") {
            @Override
            protected void paintComponent(Graphics g) {

                Graphics2D g2d = (Graphics2D) g;

                Map desktopHints = (Map) Toolkit.getDefaultToolkit().getDesktopProperty("awt.font.desktophints");
                if (desktopHints != null) {
                    g2d.addRenderingHints(desktopHints);
                    System.out.println("Desktop: " + desktopHints);
                }
                java.awt.FontMetrics fm = getFontMetrics(getFont());
                Object swingHint = fm.getFontRenderContext().getAntiAliasingHint();
                System.out.println("Swing AntiAliasingHint: " + swingHint);

                super.paintComponent(g2d);
            }
        };
        label.setBackground(Color.BLACK);
        label.setForeground(Color.LIGHT_GRAY);
        label.setOpaque(true);

        label.setFont(label.getFont().deriveFont(Font.BOLD, 14f));

        frame.add(label);
        frame.setSize(new Dimension(160, 100));
        frame.setVisible(true);
    }
}
于 2013-03-21T07:38:06.333 回答