我正在尝试在JPanel
上显示多个较小的JScrollPane
。
为实现此目的,我目前将它们添加到另一个JPanel
并将此面板设置为scrollPane的ViewportView。
有没有办法将面板直接添加到滚动窗格?
什么不起作用是这样的:
JScrollPane scrollPane = new JScrollPane();
scrollPane.setPreferredSize(new Dimension(480, 480));
scrollPane.setSize(new Dimension(480, 480));
scrollPane.setMinimumSize(new Dimension(480, 40));
scrollPane.setViewportBorder(null);
scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
System.out.println("start");
for (int i=0; i<5;i++)
{
SingleClientPanel x = new SingleClientPanel();
x.setLocation(0, 45 *i);
scrollPane.getViewport().add(x);
}
答案 0 :(得分:5)
为实现这一目标,我目前将它们添加到另一个JPanel并将此面板设置为scrollPane的视口。
不完全。您不会将容器JPanel设为视口,而是视口的视图。视口本身是一个非常专业的容器,它有自己的布局管理器,如果您只是用JPanel替换它,这将会搞砸。
即,
JViewport viewport = myScrollPane.getViewport();
viewport.setView(myContainerJPanel);
或更简洁
myScrollPane.setViewportView(myContainerJPanel);
请注意,这让我担心:x.setLocation(0, 45 *i);
并建议在某处使用null
布局。无论你做什么,都不要这样做,不要使用null
布局,特别是在JScrollPanes中,因为它会把它全部搞砸。
有关更详细的帮助,请考虑创建并发布sscce或minimal example program/mcve,其中您将代码压缩到仍然编译和运行的最小位,没有外部依赖(例如需要链接)对于数据库或图像),没有额外的代码与您的问题无关,但仍然可以证明您的问题。另外,请考虑发布所需输出的图像。
例如:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import javax.swing.*;
public class ScrollPaneEg extends JPanel {
private static final int PREF_W = 480;
private static final int PREF_H = PREF_W;
public ScrollPaneEg() {
JScrollPane scrollPane = new JScrollPane();
scrollPane.setViewportBorder(null);
scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
JPanel container = new JPanel(new GridLayout(0, 1)); // 1 column variable
// number of rows
for (int i = 0; i < 15; i++) {
SingleClientPanel x = new SingleClientPanel(String.valueOf(i + 1));
// x.setLocation(0, 45 *i);
container.add(x);
}
scrollPane.setViewportView(container);
setLayout(new BorderLayout());
add(scrollPane, BorderLayout.CENTER);
}
@Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private static void createAndShowGui() {
ScrollPaneEg mainPanel = new ScrollPaneEg();
JFrame frame = new JFrame("ScrollPaneEg");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class SingleClientPanel extends JPanel {
private static final int PREF_H = 60;
public SingleClientPanel(String text) {
setBorder(BorderFactory.createTitledBorder("Single Client"));
setLayout(new GridBagLayout());
add(new JLabel("Panel: " + text, SwingConstants.CENTER));
}
@Override
public Dimension getPreferredSize() {
Dimension superSz = super.getPreferredSize();
if (isPreferredSizeSet()) {
return superSz;
}
int prefH = Math.max(superSz.height, PREF_H);
return new Dimension(superSz.width, prefH);
}
}
另外,请考虑使用JTable来显示表格数据。例如,......
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Window;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;
import javax.swing.*;
import javax.swing.border.LineBorder;
import javax.swing.table.AbstractTableModel;
public class ClientOverviewTest {
private static void createAndShowGui() {
ClientOverviewPanel2 mainPanel = new ClientOverviewPanel2();
JFrame frame = new JFrame("ClientOverviewPanel");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class ClientOverviewPanel2 extends JPanel {
private static final int CLIENTS = 5;
private static final int PREF_W = 600;
private static final int PREF_H = 200;
private ClientTableModel model = new ClientTableModel();
private JTable table = new JTable(model);
public ClientOverviewPanel2() {
for (int i = 0; i < CLIENTS; i++) {
String ip = "127.000.000.001";
UUID uuid = UUID.randomUUID();
boolean isLocal = true;
SingleClient client = new SingleClient(ip, uuid, isLocal);
model.addRow(client);
}
table.getColumnModel().getColumn(1).setPreferredWidth(150); //!!
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
setLayout(new BorderLayout());
add(scrollPane, BorderLayout.CENTER);
add(new JButton(new OkAction("OK")), BorderLayout.PAGE_END);
}
@Override
public Dimension getPreferredSize() {
Dimension superSz = super.getPreferredSize();
if (isPreferredSizeSet()) {
return superSz;
}
int prefW = PREF_W;
int prefH = Math.min(superSz.height, PREF_H);
return new Dimension(prefW, prefH);
}
private class OkAction extends AbstractAction {
public OkAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
@Override
public void actionPerformed(ActionEvent e) {
Component source = (Component) e.getSource();
Window window = SwingUtilities.getWindowAncestor(source);
if (window != null) {
window.dispose();
}
}
}
}
class ClientTableModel extends AbstractTableModel {
public final static String[] COLUMNS = { "IP", "UUID", "Local" };
private List<SingleClient> clientList = new ArrayList<>();
@Override
public int getColumnCount() {
return COLUMNS.length;
}
@Override
public int getRowCount() {
return clientList.size();
}
@Override
public String getColumnName(int column) {
return COLUMNS[column];
}
public void addRow(SingleClient client) {
clientList.add(client);
int index = clientList.size() - 1;
fireTableRowsInserted(index, index);
}
@Override
public Object getValueAt(int rowIndex, int columnIndex) {
if (rowIndex >= getRowCount() || rowIndex < 0) {
String text = "for rowIndex: " + rowIndex;
throw new IllegalArgumentException(text);
}
if (columnIndex < 0 || columnIndex >= COLUMNS.length) {
String text = "for columnIndex: " + columnIndex;
throw new IllegalArgumentException(text);
}
SingleClient client = clientList.get(rowIndex);
switch (columnIndex) {
case 0:
return client.getIp();
case 1:
return client.getUuid();
case 2:
return client.isLocal();
}
return null;
}
@Override
public Class<?> getColumnClass(int columnIndex) {
if (columnIndex < 0 || columnIndex >= COLUMNS.length) {
String text = "for columnIndex: " + columnIndex;
throw new IllegalArgumentException(text);
}
switch (columnIndex) {
case 0:
return String.class;
case 1:
return UUID.class;
case 2:
return Boolean.class;
}
// default value
return super.getColumnClass(columnIndex);
}
@Override
public boolean isCellEditable(int rowIndex, int columnIndex) {
return columnIndex == 2;
}
@Override
public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
SingleClient client = clientList.get(rowIndex);
switch (columnIndex) {
case 0:
break;
case 1:
break;
case 2:
boolean isLocal = (boolean) aValue;
client.setLocal(isLocal);
default:
break;
}
}
}
class SingleClient {
private String ip;
private UUID uuid;
private boolean isLocal;
public SingleClient(String ip, UUID uuid2, boolean isLocal) {
this.ip = ip;
this.uuid = uuid2;
this.isLocal = isLocal;
}
public String getIp() {
return ip;
}
public void setIp(String ip) {
this.ip = ip;
}
public UUID getUuid() {
return uuid;
}
public void setUuid(UUID uuid) {
this.uuid = uuid;
}
public boolean isLocal() {
return isLocal;
}
public void setLocal(boolean isLocal) {
this.isLocal = isLocal;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((ip == null) ? 0 : ip.hashCode());
result = prime * result + ((uuid == null) ? 0 : uuid.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
SingleClient other = (SingleClient) obj;
if (ip == null) {
if (other.ip != null)
return false;
} else if (!ip.equals(other.ip))
return false;
if (uuid == null) {
if (other.uuid != null)
return false;
} else if (!uuid.equals(other.uuid))
return false;
return true;
}
}
答案 1 :(得分:0)
感谢帮助,我能够让它发挥作用。我将添加我的解决方案,包括更改以供参考和进一步评论:
public class SingleClientPanel extends JPanel
{
private JTextField ipTextfield;
private JTextField uuidTextField;
public SingleClientPanel()
{
this("127.000.000.001",UUID.randomUUID().toString(),true);
}
public SingleClientPanel(String ip, String uuid,boolean isLocal)
{
/*
removed:
setSize(new Dimension(440, 35));
setPreferredSize(new Dimension(440, 35));
setMaximumSize(new Dimension(440, 35));
setMinimumSize(new Dimension(440, 35));*/
setBorder(new LineBorder(new Color(0, 0, 0), 1, true));
setLayout(new BoxLayout(this, BoxLayout.X_AXIS)); // added this
ipTextfield = new JTextField();
ipTextfield.setHorizontalAlignment(SwingConstants.CENTER);
ipTextfield.setAlignmentX(Component.LEFT_ALIGNMENT);
ipTextfield.setFocusable(false);
ipTextfield.setEditable(false);
add(ipTextfield);
ipTextfield.setColumns(15);
ipTextfield.setText(ip);
uuidTextField = new JTextField();
uuidTextField.setHorizontalAlignment(SwingConstants.CENTER);
uuidTextField.setEditable(false);
uuidTextField.setFocusable(false);
add(uuidTextField);
uuidTextField.setColumns(30);
uuidTextField.setText(uuid);
JButton button = new JButton(">");
button.setEnabled(!isLocal);
add(button);
this.revalidate();
}
}
public class ClientOverviewPanel extends JPanel
{
public ClientOverviewPanel()
{
setLayout(new BorderLayout(0, 0));
JButton btnOk = new JButton("Ok");
btnOk.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent arg0)
{
Window x = SwingUtilities.getWindowAncestor(ClientOverviewPanel.this);
if(x != null) x.dispose();
}
});
add(btnOk, BorderLayout.SOUTH);
JScrollPane scrollPane = new JScrollPane();
/*
removed:
scrollPane.setPreferredSize(new Dimension(480, 480));
scrollPane.setSize(new Dimension(480, 480));
scrollPane.setMinimumSize(new Dimension(480, 40));*/
scrollPane.setViewportBorder(null);
scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
Box box = new Box(BoxLayout.PAGE_AXIS); //added
for (int i=0; i<5;i++)
{
SingleClientPanel cpan = new SingleClientPanel();
//cpan.setLocation(0, 45 *i); removed
box.add(cpan); //changed
}
scrollPane.setViewportView(box); //changed
add(scrollPane, BorderLayout.CENTER);
this.revalidate();
}
}