JTextPane不显示JScrollPane,也不显示文本

Question

我需要显示链接,所以我正在使用带有setContentType的JTextPane.但是,内容不会换行,也没有滚动.JTextPane的内容将从RSS源返回.这是完整的代码:

import java.awt.*;
import javax.swing.*;

class Main extends JFrame
{
    JFrame frame;
    JTabbedPane tabbedPane;
    JPanel home, news;      

    public Main()
    {
        setTitle("My Title" ); 
        setSize( 900, 600 ); 
        setLocationRelativeTo(null); 
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 

        home(); 
        news(); 

        tabbedPane = new JTabbedPane(); 
        tabbedPane.addTab( " Home", home ); 
        tabbedPane.addTab( "News", news ); 

        JPanel framePanel = new JPanel();
        framePanel.setLayout(new BorderLayout());       
        framePanel.add( tabbedPane, BorderLayout.CENTER );
        getContentPane().add( framePanel );     

    }


    public void home() 
    {       
        home = new JPanel();
        // some stuffs here
    }


    public void news()
    {
        news = new JPanel();

        JTextPane newsTextPane = new JTextPane(); 
        newsTextPane.setContentType("text/html");
        newsTextPane.setEditable(false); 

        JScrollPane scrollPane = new JScrollPane(newsTextPane);     
        scrollPane.setVerticalScrollBarPolicy(javax.swing.ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
        news.add(scrollPane);   

        RSS reader = RSS .getInstance();
        reader.writeNews();             

        String rssNews = reader.writeNews();
        newsTextPane.setText(rssNews);
    }   

    public static void main( String args[] )
    {

        RSS reader = RSS.getInstance();
        reader.writeNews();

        Main mainFrame  = new Main();
        mainFrame.setVisible( true );   
        mainFrame.setDefaultCloseOperation( EXIT_ON_CLOSE );
        }
}

我的结果:

Answer 1

我只是使用你的代码,它不会导致任何问题:

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.SwingUtilities

public class TestScrolling {

    public static void main(String[] args) {
            SwingUtilities.invokeLater(new Runnable() {
                 public void run() {
                  initUI();
                 });
    }

    public static void initUI() {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < 100; i++) {
            sb.append("loads loads loads loads of text here ");
        }
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JTextPane newsTextPane = new JTextPane();
        newsTextPane.setContentType("text/html");
        newsTextPane.setEditable(false);
        newsTextPane.setText(sb.toString());

        JScrollPane scrollPane = new JScrollPane(newsTextPane);
        scrollPane.setVerticalScrollBarPolicy(
                  javax.swing.ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED);
        frame.add(scrollPane);
        frame.setSize(300, 200);
        frame.setVisible(true);
     }
}

编辑:

你必须以某种方式强制scrollPane的宽度.在我的示例中,它通过将滚动窗格添加到框架的内容窗格来隐式完成,默认情况下使用BorderLayout.在您的情况下,您使用了一个FlowLayout,它分配了滚动窗格的首选大小,该大小与JTextPane的首选大小有关.