java - 如何在 JScrollPane 中显示项目列表？

Question

首先，我是一名编程初学者，我不懂很多 Java/编程术语，所以如果您能够帮助我，请尝试用更简单的语言解释。

我正在尝试在 JScrollPane 中显示单词列表。该列表由 WordList 类表示。 JScrollPane 位于另一个名为 WordFinder 的类中。

在 WordFinder 中，代码类似于:

WordList words = new WordList();

// (other GUI code in between)

JScrollPane scrollPane = new JScrollPane(DONT_KNOW);

如果我将“单词”放在 DONT_KNOW 所在的位置，我会收到一条警告:“构造函数 JScrollPane(WordList) 未定义”。我可以理解，JScrollPane 不应该接受这个奇怪的随机类。但那我该放什么呢？我知道您可以将 JList 放入 JScrollPane 中，但是如何将 WordList 类转换为 JList (或 JScrollPane 接受的东西)？

我不确定这是否有帮助，但这是 WordList 类中的代码(我没有写这个；它是给我的):

    import java.io.*;
    import java.net.URL;
    import java.text.Collator;
    import java.util.*;

    /**
     * A WordList is a set of words loaded from a file and searchable by substring.
     * A word is defined as a sequence of letters (upper case or lower case).
     * WordSets ignore alphabetic case when comparing, searching, or sorting.
     */
    public class WordList {
        private List words;

        /*
         * Rep invariant: words != null
         */

    public WordList() {

    }

    public void load(InputStream in) throws IOException {
        Collator c = Collator.getInstance();
        c.setStrength(Collator.PRIMARY);
        Set s = new TreeSet(c);

        StreamTokenizer tok = new StreamTokenizer(new InputStreamReader(in));
        tok.resetSyntax();
        tok.wordChars('a', 'z');
        tok.wordChars('A', 'Z');

        while (tok.nextToken() != StreamTokenizer.TT_EOF) {
            if (tok.ttype == StreamTokenizer.TT_WORD)
                s.add(tok.sval);
        }

        words = new ArrayList(s);
    }

    public List find(String s) {
        if (s.length() == 0) {
            return Collections.unmodifiableList(words);
        }

        s = s.toLowerCase();

        List l = new ArrayList();
        for (Iterator i = words.iterator(); i.hasNext();) {
            String word = (String) i.next();
            if (word.toLowerCase().indexOf(s) != -1)
                l.add(word);
        }
        return l;
    }

    /**
     * Main method. Demonstrates how to use this class.
     * 
     * @param args
     *            Command-line arguments. Ignored.
     */
    public static void main(String[] args) {
        WordList words = new WordList();

        // Create the word list from a resource.
        // The words file must be in the same directory (or jar file directory)
        // as this class.
        URL url = WordList.class.getResource("words.txt");
        if (url == null)
            throw new RuntimeException("Missing resource: words");
        try {
            words.load(url.openStream());
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        // Print all the words containing "ph"
        List matches = words.find("holst");
        for (Iterator i = matches.iterator(); i.hasNext();) {
            System.out.println(i.next());
        }
    }
}

Answer 1

在 JScrollPane 中使用 JList。

这是示例。

    JList list;
    DefaultListModel listModel;
    listModel = new DefaultListModel();
    listModel.addElement("word1");
    listModel.addElement("word2");
    listModel.addElement("word3");

    //Create the list and put it in a scroll pane.
    list = new JList(listModel);
    list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    list.setSelectedIndex(0);
    list.addListSelectionListener(this);
    list.setVisibleRowCount(5);
    JScrollPane listScrollPane = new JScrollPane(list);

上面的例子来自ListDemo.java

结账 Oracle's tutorial在 JList 上。