今天我和JList一起玩,然后我发现了一个问题。 我知道我的田地没有好名字,但正如我所说,我只是在玩耍。
我想为我的JList创建一个水平和垂直的JScrollPane。实际上,它有效,但仍然存在问题。
我的代码:
final JList list = new JList(GUI.strings.toArray());
JScrollPane scrollPane = new JScrollPane(list);
JScrollPane scrollPanex = new JScrollPane(scrollPane);
scrollPanex.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
getContentPane().add(scrollPanex, BorderLayout.CENTER);
有没有办法解决这个问题,所以我总能看到两个滚动条?
答案 0 :(得分:3)
只需使用一个JScrollPane,然后设置单个JScrollPane的两个滚动条策略。
final JList list = new JList(GUI.strings.toArray());
JScrollPane scrollPane = new JScrollPane(list);
scrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS);
scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
getContentPane().add(scrollPane, BorderLayout.CENTER);
如,
import java.awt.Dimension;
import java.util.Random;
import javax.swing.DefaultListModel;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JViewport;
import javax.swing.SwingUtilities;
public class ScrollPaneFun {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
Random rand = new Random();
DefaultListModel<String> lModel = new DefaultListModel<>();
JList<String> myList = new JList<>(lModel);
myList.setVisibleRowCount(20);
for (int i = 0; i < 50; i++) {
StringBuilder sb = new StringBuilder();
sb.append(String.valueOf(i) + ": ");
for (int j = 0; j < 50; j++) {
for (int k = 0; k < 3; k++) {
char c = (char) ('a' + rand.nextInt('z' - 'a' + 1));
sb.append(c);
}
sb.append(' ');
}
lModel.addElement(sb.toString());
}
JScrollPane scrollPane = new JScrollPane(myList);
scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
JViewport viewport = scrollPane.getViewport();
int w = 400;
int h = viewport.getPreferredSize().height;
Dimension preferredSize = new Dimension(w, h);
viewport.setPreferredSize(preferredSize);
JOptionPane.showMessageDialog(null, scrollPane);
}
});
}
}