java滚动条不会出现在JList上
我正在使用一个GridBagLayout
并有一个JList
的自定义类。JList
本身如我所料显示,但滚动条没有出现。(我的数据大小也大于我的JList
。)我查看了很多相关链接,所有的链接都提到了这两行,但这对我来说不起作用
JScrollPane scrollPane = new JScrollPane(list);
add(scrollPane);
完整代码:
import java.awt.Button;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Label;
import javax.swing.*;
public class UserPart extends JFrame {
Label messageL = new Label("Confirm an item for more options.");
Button confirmB = new Button("Confirm");
Button backB = new Button("Back");
DefaultListModel<User2> model;
public UserPart() {
JList<User2> list = new JList<User2>();
model = new DefaultListModel<User2>();
for (int i = 0; i < MainActivity2.arr.size(); i++) {
User2 u = new User2();
u.setForShow(i);
model.addElement(u);
}
// SETTING THE APPEARANCE OF THE JLIST
list.setModel(model);
list.setCellRenderer(new MyListCellRenderer());
list.setLayoutOrientation(JList.VERTICAL);
list.setPreferredSize(new Dimension(500, 750));
//////////////////////////////////////////////
GridBagLayout grid = new GridBagLayout();
GridBagConstraints gbc = new GridBagConstraints();
setLayout(grid);
setTitle("List of users");
GridBagLayout layout = new GridBagLayout();
this.setLayout(layout);
gbc.gridx = 0;
gbc.gridy = 0;
this.add(messageL, gbc);
gbc.gridx = 0;
gbc.gridy = 1;
this.add(list, gbc); //ADDED JLIST TO LAYOUT HERE
JScrollPane scrollPane = new JScrollPane(list); // DEFINED SCROLL BAR HERE
add(scrollPane); // ADDED SCROLL BAR TO LAYOUT HERE
setSize(1000, 1500);
setPreferredSize(getSize());
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
}
# 1 楼答案
将约束权重(
weightx
,weighty
)设置为大于零的值-要使用所有布局-还将fill
设置为BOTH
。不要直接将列表添加到框架中,只需添加滚动窗格,并设置上述约束。不要将AWT组件(Label
)与Swing组件混合使用,而是使用JLabel
。总结如下: