Good afternoon! It is necessary to make a list (vertical) from lists of events (horizontal). There are at least 2 problems:

1. the area of the list of events (horizontal scrolling) expands beyond the borders of the panel. Apparently, the problem is with Layout, but I can not find the right combination;
2. horizontal scrolling does not work (probably due to the problem described above) and the scrollbar must be different for each group of events.

import ivank.components.EventAdd;
 
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
 
public class WindowAddCameras extends JFrame {
    public static final List<JPanel> labels = new ArrayList<JPanel>();
 
    public WindowAddCameras() {
        super("Добавить камеру");
 
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
        JPanel panelButton = new JPanel();
 
        JButton addButton = new JButton(" ");
        addButton.setFocusable(false);
        panelButton.add(addButton);
 
        JButton remButton = new JButton("-");
        remButton.setFocusable(false);
        panelButton.add(remButton);
 
        JPanel externalPanel = new JPanel();
        externalPanel.setLayout(new BorderLayout(0, 0));
        JScrollPane scrollPaneGroupEvent = new JScrollPane(
                externalPanel,
                JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
                JScrollPane.HORIZONTAL_SCROLLBAR_NEVER
        );
 
        JPanel internalPanel = new JPanel();
        internalPanel.setLayout(new GridLayout(0, 1, 0, 0));
 
        JScrollPane scrollPaneEvent = new JScrollPane(internalPanel);
        scrollPaneEvent.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);
        scrollPaneEvent.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
 
        externalPanel.add(scrollPaneEvent, BorderLayout.NORTH);
        addButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                int number = labels.size()   1;
                EventAdd eventAdd = new EventAdd();
                Dimension labelSize = new Dimension(80, 80);
 
                //add event to group event
                Random rand = new Random();
                for(int a = 0; a < 20; a  ) {
                    //random color border event for TEST
                    Color randomColor = new Color(rand.nextFloat(), rand.nextFloat(), rand.nextFloat());
                    eventAdd.createEventLabel("Камера "   number, labelSize, randomColor);
                }
 
                labels.add(eventAdd);
                internalPanel.add(eventAdd, BorderLayout.NORTH);
                scrollPaneGroupEvent.revalidate();
            }
        });
 
        remButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if(labels.size() > 0) {
                    int index = labels.size() - 1;
                    JPanel panel = labels.remove(index);
                    internalPanel.remove(panel);
                    internalPanel.repaint();
                    scrollPaneGroupEvent.revalidate();
                }
            }
        });
 
        this.getContentPane().setLayout(new BorderLayout());
        this.getContentPane().add(panelButton, BorderLayout.NORTH);
        this.getContentPane().add(scrollPaneGroupEvent, BorderLayout.CENTER);
 
        this.setPreferredSize(new Dimension(600, 400));
        this.pack();
        this.setLocationRelativeTo(null);
        this.setVisible(true);
    }
}

package ivank.components;
 
import javax.swing.*;
import java.awt.*;
import java.util.ArrayList;
 
public class EventAdd extends JPanel {
    public EventAdd() {
        super(new FlowLayout(FlowLayout.LEFT));
    }
 
    public JComponent createEventLabel(String name, Dimension labelSize, Color randomColor) {
        this.setBorder(BorderFactory.createTitledBorder(name));
        JLabel label = new JLabel();
        label.setPreferredSize(labelSize);
        label.setHorizontalAlignment(JLabel.CENTER);
 
        label.setBorder(BorderFactory.createLineBorder(randomColor, 5));
        this.add(label);
 
        return label;
    }
}

What I have: enter image description here What I want to get: enter image description here

CodePudding user response：

You can do the horizontal and vertical scrolling with only one JScrollPane. But what you need is an underlying JComponent that renders your content. This however can be a JPanel that stretches as far as you need.

Have a look at How to use ScrollPanes.

CodePudding user response：

A JScrollPane must have a JViewport assigned using the jscrollpane method setViewportView. You should also give it a scrollbar policy setVerticalScrollBarPolicy setHorizontalScrollBarPolicy The policy int is part of the class for the two previous methods and are called "constant field values" , see the API doc for JScrollPane. To expand the JScrollPane out, put it in a JPanel with a BorderLayout and NO OTHER elements in that particular panel with the JScrollPane. Use on the JPanel, the methods setMinimumSize and setPreferredSize and setSize or a BoxLayout in the main window(although i think main windows have a special layout so a boxlayout would not be required if so) or higher level panel in the stack, or just setPreferredSize for the JScrollPane. A jscrollpane has a view set by its "setView" method , its view is a java.awt.Component note: a JComponent is a java.awt.Component, any javax swing J panel or J viewport is a java.awt.Component by hierarchy. NOTE a jviewport is a java.awt.Component so get a jscrollpane.setViewportView add the jviewport reference jviewport.setView as the JPanel with the BorderLayout , add another panel to start adding other components, but remember to give all Jcomponents a .preferredSize method use. If you are after javax.swing.JList<E> and javax.swing.DefaultListModel<E> The JList must be placed in a JPanel with a BorderLayout , or much more difficult system a java.awt.GridBagLayout then in a jscrollpane.