Java图形无法更改字体

Question

I am trying to do a custom painting using the Graphics object. I want to paint the text in word-wrap style, so i used some example code i found somewhere on this page.

My problem is that i cannot change the font-size in any way. Please help me, I attached the executable source code below.

Thanks

Chris

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.font.LineBreakMeasurer;
import java.awt.font.TextLayout;
import java.text.AttributedCharacterIterator;
import java.text.AttributedString;

import javax.swing.JFrame;

public class JavaFontProblem extends JFrame {

    public JavaFontProblem() {
        setSize(new Dimension(1024, 768));
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public void paint(Graphics g) {

        Graphics2D g2d = (Graphics2D) g;
        String longtext = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.";

        g2d.setColor(Color.BLACK);
        g2d.setFont(new Font("Verdana", Font.PLAIN, 250));

        AttributedString atString = new AttributedString(longtext);
        AttributedCharacterIterator iterator = atString.getIterator();

        LineBreakMeasurer measurer = new LineBreakMeasurer(iterator, g2d
                .getFontRenderContext());
        measurer.setPosition(iterator.getBeginIndex());

        int m_width = 500;

        float x = 50, y = 50;
        while (measurer.getPosition() < iterator.getEndIndex()) {
            TextLayout layout = measurer.nextLayout(m_width);

            y += layout.getAscent();
            float dx = layout.isLeftToRight() ? 0 : m_width
                    - layout.getAdvance();

            layout.draw(g2d, x + dx, y);
            y += layout.getDescent() + layout.getLeading();
        }

    }

    public static void main(String[] args) {
        new JavaFontProblem().setVisible(true);
    }

}

Answer 1

atString.addAttribute(TextAttribute.FONT, myFont, 0, atString.length());

Answer 2

You need to send the length of the longtext...not the atString length

Also, you will have to declare your own Font object. It also negates the need to have your setFont.

import java.awt.font.TextAttribute;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.font.LineBreakMeasurer;
import java.awt.font.TextLayout;
import java.text.AttributedCharacterIterator;
import java.text.AttributedString;

import javax.swing.JFrame;

public class JavaFontProblem extends JFrame {

    public JavaFontProblem() {
        setSize(new Dimension(1024, 768));
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public void paint(Graphics g) {

        Graphics2D g2d = (Graphics2D) g;
        String longtext = "Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.";

        g2d.setColor(Color.BLACK);
        //g2d.setFont(new Font("Verdana", Font.PLAIN, 250));

        Font myFont = new Font("Verdana", Font.PLAIN, 250);

        AttributedString atString = new AttributedString(longtext);
        atString.addAttribute(TextAttribute.FONT, myFont, 0, longtext.length());


        AttributedCharacterIterator iterator = atString.getIterator();

        LineBreakMeasurer measurer = new LineBreakMeasurer(iterator, g2d
                        .getFontRenderContext());
        measurer.setPosition(iterator.getBeginIndex());

        int m_width = 500;

        float x = 50, y = 50;
        while (measurer.getPosition() < iterator.getEndIndex()) {
                TextLayout layout = measurer.nextLayout(m_width);

                y += layout.getAscent();
                float dx = layout.isLeftToRight() ? 0 : m_width
                                - layout.getAdvance();

                layout.draw(g2d, x + dx, y);
                y += layout.getDescent() + layout.getLeading();
        }

    }

    public static void main(String[] args) {
        new JavaFontProblem().setVisible(true);
    }

}