Java Swing可滚动JPanel,框架上有多个面板

Java Swing可滚动JPanel,框架上有多个面板,java,swing,jpanel,jscrollpane,Java,Swing,Jpanel,Jscrollpane,我有一个JFrame,它有两个JPanel。首先是标题,然后是主内容面板。我想让我的第二个内容面板可以滚动,但即使滚动条出现在面板上,它似乎并没有扩展到它的真实高度。在我的第二个JPanel中称为p2,我添加了20个小JPanel,这应该会导致它在高度上扩展,但它没有这样做。下面是我的代码: public class DisplayItems3{ public static void main(String[] args) { JFrame frame = new J

我有一个JFrame,它有两个JPanel。首先是标题,然后是主内容面板。我想让我的第二个内容面板可以滚动,但即使滚动条出现在面板上,它似乎并没有扩展到它的真实高度。在我的第二个JPanel中称为p2,我添加了20个小JPanel,这应该会导致它在高度上扩展,但它没有这样做。下面是我的代码:

public class DisplayItems3{

    public static void main(String[] args) {

        JFrame frame = new JFrame();

        final int FRAME_WIDTH  = 1000;
        final int FRAME_HEIGHT = 1000;

        frame.setSize(FRAME_WIDTH, FRAME_HEIGHT);
        frame.setTitle("Home Library");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new FlowLayout());

        //Top Panel
        JPanel p1 = new JPanel();
        p1.setLayout(new FlowLayout());
        p1.setBackground(Color.LIGHT_GRAY);
        p1.setPreferredSize(new Dimension(950, 100));

        JLabel l1 = new JLabel("All Library Items");
        l1.setForeground(Color.BLACK);
        l1.setPreferredSize(new Dimension(900, 50));
        l1.setFont(l1.getFont().deriveFont(30.0f));

        p1.add(l1);

        //Content Panel
        JPanel p2 = new JPanel();
        p2.setLayout(new FlowLayout());
        p2.setBackground(Color.LIGHT_GRAY);
        p2.setPreferredSize(new Dimension(950, 800));
        p2.setAutoscrolls(true);

        JScrollPane scrollPane = new JScrollPane(p2);
        scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
        scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
        scrollPane.setBounds(0, 0, 950, 800);

        JPanel contentPane = new JPanel(null);
        contentPane.setPreferredSize(new Dimension(950, 800));
        contentPane.add(scrollPane);

        for(int i = 0; i < 20; i++) {

            JPanel sp1 = new JPanel();
            sp1.setLayout(new FlowLayout());
            sp1.setBackground(Color.WHITE);
            sp1.setPreferredSize(new Dimension(900, 180));

            p2.add(sp1);    

        }


        //contentPane.add(p2);
        frame.add(p1);
        //frame.add(p2);
        //frame.setContentPane(contentPane);
        frame.add(contentPane);

        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.setVisible(true);

    }

}
公共类显示项3{
公共静态void main(字符串[]args){
JFrame=新JFrame();
最终整数帧_宽度=1000;
最终整数帧高度=1000;
框。设置尺寸(框宽、框高);
frame.setTitle(“主库”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(新的FlowLayout());
//顶板
JPanel p1=新的JPanel();
p1.setLayout(新的FlowLayout());
p1.立根背景(颜色:浅灰色);
p1.设置首选尺寸(新尺寸(950100));
JLabel l1=新的JLabel(“所有库项”);
l1.设置前景(颜色为黑色);
l1.设置首选尺寸(新尺寸(900,50));
l1.setFont(l1.getFont().deriveFont(30.0f));
p1.添加(l1);
//内容面板
JPanel p2=新的JPanel();
p2.setLayout(新的FlowLayout());
p2.立根背景(颜色:浅灰色);
p2.设置首选尺寸(新尺寸(950800));
p2.设置自动滚动(真);
JScrollPane scrollPane=新的JScrollPane(p2);
scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HorizontalScrollBar\uNever);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL\u SCROLLBAR\u根据需要);
滚动窗格.setBounds(0,0,950,800);
JPanel contentPane=新的JPanel(null);
setPreferredSize(新维度(950800));
添加(滚动窗格);
对于(int i=0;i<20;i++){
JPanel sp1=新的JPanel();
setLayout(新的FlowLayout());
sp1.挫折背景(颜色:白色);
设置首选尺寸(新尺寸(900,180));
p2.添加(sp1);
}
//contentPane.add(p2);
帧。添加(p1);
//帧。添加(p2);
//frame.setContentPane(contentPane);
frame.add(contentPane);
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setVisible(true);
}
}

使用JList更新

没用

public class JListTest {

    public static void main(String[] args) {

        JFrame frame = new JFrame();

        final int FRAME_WIDTH  = 1000;
        final int FRAME_HEIGHT = 1000;

        frame.setSize(FRAME_WIDTH, FRAME_HEIGHT);
        frame.setTitle("Home Library");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new FlowLayout());

        //Top Panel
        JPanel p1 = new JPanel();
        p1.setLayout(new FlowLayout());
        p1.setBackground(Color.LIGHT_GRAY);
        p1.setPreferredSize(new Dimension(950, 100));

        JLabel l1 = new JLabel("All Library Items");
        l1.setForeground(Color.BLACK);
        l1.setPreferredSize(new Dimension(900, 50));
        l1.setFont(l1.getFont().deriveFont(30.0f));

        p1.add(l1);

        JList ll1 = new JList();
        ll1.setLayout(new FlowLayout());
        ll1.setBackground(Color.LIGHT_GRAY);
        ll1.setPreferredSize(new Dimension(950, 800));
        ll1.setAutoscrolls(true);

        JScrollPane scrollPane = new JScrollPane(ll1);
        scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
        scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
        scrollPane.setBounds(0, 0, 950, 800);

        for(int i = 0; i < 20; i++) {

            JPanel sp1 = new JPanel();
            sp1.setLayout(new FlowLayout());
            sp1.setBackground(Color.WHITE);
            sp1.setPreferredSize(new Dimension(900, 180));

            ll1.add(sp1);    

        }


        //contentPane.add(p2);
        frame.add(p1);
        frame.add(scrollPane);
        //frame.setContentPane(contentPane);
        //frame.add(contentPane);

        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.setVisible(true);

    }

}
公共类测试{
公共静态void main(字符串[]args){
JFrame=新JFrame();
最终整数帧_宽度=1000;
最终整数帧高度=1000;
框。设置尺寸(框宽、框高);
frame.setTitle(“主库”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(新的FlowLayout());
//顶板
JPanel p1=新的JPanel();
p1.setLayout(新的FlowLayout());
p1.立根背景(颜色:浅灰色);
p1.设置首选尺寸(新尺寸(950100));
JLabel l1=新的JLabel(“所有库项”);
l1.设置前景(颜色为黑色);
l1.设置首选尺寸(新尺寸(900,50));
l1.setFont(l1.getFont().deriveFont(30.0f));
p1.添加(l1);
JList ll1=新JList();
ll1.setLayout(新的FlowLayout());
ll1.立根背景(颜色:浅灰色);
ll1.设置首选尺寸(新尺寸(950800));
ll1.设置自动滚动(真);
JScrollPane scrollPane=新的JScrollPane(ll1);
scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HorizontalScrollBar\uNever);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL\u SCROLLBAR\u ALWAYS);
滚动窗格.setBounds(0,0,950,800);
对于(int i=0;i<20;i++){
JPanel sp1=新的JPanel();
setLayout(新的FlowLayout());
sp1.挫折背景(颜色:白色);
设置首选尺寸(新尺寸(900,180));
ll1.add(sp1);
}
//contentPane.add(p2);
帧。添加(p1);
frame.add(滚动窗格);
//frame.setContentPane(contentPane);
//frame.add(contentPane);
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setVisible(true);
}
}
问题已解决:工作代码

public class scrollTest2 {

    public static void main(String[] args)
    {
        JFrame frame = new JFrame();

        final int FRAME_WIDTH  = 1000;
        final int FRAME_HEIGHT = 1000;

        frame.setSize(FRAME_WIDTH, FRAME_HEIGHT);
        frame.setTitle("Home Library");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new BorderLayout());

        JLabel m1 = new JLabel("safsd");

        JPanel panel = new JPanel();
        panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
        panel.setAutoscrolls(true);
        frame.add(panel,BorderLayout.NORTH);

        JScrollPane scrollPane = new JScrollPane(panel);
        scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
        scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
        scrollPane.setBounds(50, 30, 800, 800);

        JPanel contentPane = new JPanel(null);
        contentPane.setPreferredSize(new Dimension(900, 900));
        contentPane.add(scrollPane);

        for(int i = 0; i < 30; i++) {

            JPanel sp1 = new JPanel();
            sp1.setLayout(new FlowLayout());
            sp1.setBackground(Color.WHITE);
            sp1.setPreferredSize(new Dimension(900, 180));

            JPanel ssp1 = new JPanel();
            ssp1.setLayout(new FlowLayout());
            ssp1.setBackground(Color.WHITE);
            ssp1.setPreferredSize(new Dimension(500, 170));

            JPanel ssp2 = new JPanel();
            ssp2.setLayout(new FlowLayout());
            ssp2.setBackground(Color.WHITE);
            ssp2.setPreferredSize(new Dimension(350, 170));

            JLabel l3 = new JLabel("Title: ");
            l3.setForeground(Color.BLACK);
            l3.setPreferredSize(new Dimension(100, 20));
            JTextField t1 = new JTextField("Electronic Basics");
            t1.setPreferredSize(new Dimension(320, 20));

            JLabel l4 = new JLabel("Type: ");
            l4.setForeground(Color.BLACK);
            l4.setPreferredSize(new Dimension(100, 20));
            JTextField t2 = new JTextField("Book");
            t2.setPreferredSize(new Dimension(320, 20));

            JLabel l5 = new JLabel("Authors: ");
            l5.setForeground(Color.BLACK);
            l5.setPreferredSize(new Dimension(100, 20));
            JTextField t3 = new JTextField("Bob the Builder");
            t3.setPreferredSize(new Dimension(320, 20));

            JLabel l6 = new JLabel("Publisher: ");
            l6.setForeground(Color.BLACK);
            l6.setPreferredSize(new Dimension(100, 20));
            JTextField t4 = new JTextField("ABC Company");
            t4.setPreferredSize(new Dimension(320, 20));

            JLabel l7 = new JLabel("Location: ");
            l7.setForeground(Color.BLACK);
            l7.setPreferredSize(new Dimension(100, 20));
            JTextField t5 = new JTextField("Shelf 1 Row 3");
            t5.setPreferredSize(new Dimension(320, 20));

            JLabel l8 = new JLabel("Status: ");
            l8.setForeground(Color.BLACK);
            l8.setPreferredSize(new Dimension(100, 20));
            JTextField t6 = new JTextField("Available");
            t6.setPreferredSize(new Dimension(320, 20));

            JButton btnLoanHistory = new JButton("Loan History");
            btnLoanHistory.setPreferredSize(new Dimension(300, 20));
            JButton btnLoanItem = new JButton("Loan Item");
            btnLoanItem.setPreferredSize(new Dimension(300, 20));
            JButton btnProcessReturn = new JButton("Process Return");
            btnProcessReturn.setPreferredSize(new Dimension(300, 20));

            ssp1.add(l3);
            ssp1.add(t1);
            ssp1.add(l4);
            ssp1.add(t2);
            ssp1.add(l5);
            ssp1.add(t3);
            ssp1.add(l6);
            ssp1.add(t4);
            ssp1.add(l7);
            ssp1.add(t5);
            ssp1.add(l8);
            ssp1.add(t6);

            ssp2.add(btnLoanHistory);
            ssp2.add(btnLoanItem);
            ssp2.add(btnProcessReturn);

            sp1.add(ssp1);
            sp1.add(ssp2);
            panel.add(sp1); 

        }

        frame.add(m1, BorderLayout.NORTH);
        frame.add(contentPane, BorderLayout.CENTER);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.setVisible(true);
    }

}
公共类scrollTest2{
公共静态void main(字符串[]args)
{
JFrame=新JFrame();
最终整数帧_宽度=1000;
最终整数帧高度=1000;
框。设置尺寸(框宽、框高);
frame.setTitle(“主库”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(新的BorderLayout());
JLabel m1=新JLabel(“safsd”);
JPanel面板=新的JPanel();
panel.setLayout(新的BoxLayout(panel,BoxLayout.Y_轴));
panel.setAutoscrolls(真);
框架。添加(面板,边框布局。北);
JScrollPane scrollPane=新的JScrollPane(面板);
scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HorizontalScrollBar,根据需要);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL\u SCROLLBAR\u根据需要);
滚动窗格.立根(50,30,800,800);
JPanel contentPane=新的JPanel(null);
setPreferredSize(新维度(900900));
添加(滚动窗格);
对于(int i=0;i<30;i++){
JPanel sp1=新的JPanel();
setLayout(新的FlowLayout());
sp1.挫折背景(颜色:白色);
设置首选尺寸(新尺寸(900,180));
JPanel ssp1=新的JPanel();
ssp1.setLayout(新的FlowLayout());
ssp1.立根背景(颜色:白色);
ssp1.设置首选尺寸(新尺寸(500170));
JPanel ssp2=新的JPanel();
ssp2.setLayout(新的FlowLayout());
ssp2.退根地面(颜色为白色
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.GridLayout;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.border.LineBorder;

public class DisplayItems3 {

    public static void main(final String[] args) {

        JFrame frame = new JFrame();

        final int FRAME_WIDTH = 1000;
        final int FRAME_HEIGHT = 1000;

        frame.setSize(FRAME_WIDTH, FRAME_HEIGHT);
        frame.setTitle("Home Library");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLayout(new FlowLayout());

        // Top Panel
        JPanel p1 = new JPanel();
        p1.setLayout(new FlowLayout());
        p1.setBackground(Color.LIGHT_GRAY);
        p1.setPreferredSize(new Dimension(950, 100));

        JLabel l1 = new JLabel("All Library Items");
        l1.setForeground(Color.BLACK);
        l1.setPreferredSize(new Dimension(900, 50));
        l1.setFont(l1.getFont().deriveFont(30.0f));

        p1.add(l1);

        // Content Panel
        JPanel p2 = new JPanel();
        p2.setLayout(new GridLayout(-1, 1));
        p2.setBackground(Color.LIGHT_GRAY);
        p2.setPreferredSize(new Dimension(950, 800));
        p2.setAutoscrolls(true);

        JScrollPane scrollPane = new JScrollPane(p2);
        scrollPane.setHorizontalScrollBarPolicy(
                JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
        scrollPane.setVerticalScrollBarPolicy(
                JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
        scrollPane.setBounds(0, 0, 950, 800);

        JPanel contentPane = new JPanel(new BorderLayout());
        contentPane.setPreferredSize(new Dimension(950, 800));
        contentPane.add(scrollPane, BorderLayout.CENTER);

        for (int i = 0; i < 20; i++) {

            JPanel sp1 = new JPanel();
            sp1.setLayout(new FlowLayout());
            sp1.setBackground(Color.WHITE);
            sp1.setPreferredSize(new Dimension(900, 180));
            sp1.setBorder(new LineBorder(Color.RED));

            p2.add(sp1);

        }

        // contentPane.add(p2);
        contentPane.add(p1, BorderLayout.NORTH);
        // frame.add(p2);
        // frame.setContentPane(contentPane);
        frame.add(contentPane);

        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.setVisible(true);

    }

}