In my Java application, I need to display a window with two vertical panels. The first panel displays some icons in a vertical column. When an icon is clicked, the second panel should show a corresponding panel. Those who are familiar with Videolan VLC, the preferences dialog in VLC displays something similar.
I searched the net. Looks like I might be able to make it work using CardLayout. However, I am wondering if the framework provides a better construct. I am thinking this is such a common design pattern, there must be something already established in the framework. Regards.
For the "icons" panel you could use a JToolBar. You can specify vertical orientation for the tool bar like this:
new JToolBar(SwingConstants.VERTICAL);
You can add the tool bar for the WEST or EAST side of a panel having a BorderLayout layout manager, and add the content to the CENTER of the panel.
As an alternative you could use a JTabbedPane and the tab placement to be on the left like this:
new JTabbedPane(JTabbedPane.LEFT);
That way you would not need to manage 2 panels. And the tabbed pane takes care of the content switching for you. If you want only icons, you can add tabs without a text:
tabbedPane.addTab("", icon, component); // empty string or you can use null
JTabbedPane, set to show the key values to the left
JList on the left, with a JPanel with a CardLayout on the right. Each value from the JList could maintain the key for the CardLayout which would show the corresponding pane
JTree, configured correctly, well allow you to show hirarcal configuraiton elements...
Of course, you could just roll your own...
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
System.out.println(getClass().getResource("/playlist.png"));
System.out.println(getClass().getResource("playlist.png"));
JPanel options = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.anchor = GridBagConstraints.WEST;
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(1, 1, 1, 1);
options.add(new ConfigPane("Playlist",
new String[]{"Playlist", "/playlist.png"},
new String[]{"Media Library", "/library.png"}), gbc);
options.add(new ConfigPane("My Computer",
new String[]{"My Videos", "/movie.png"},
new String[]{"My Music", "/music.png"},
new String[]{"My Pictures", "/pictures.png"}), gbc);
options.add(new ConfigPane("Devices",
new String[]{"Discs", "/disc.png"}), gbc);
options.add(new ConfigPane("Local Network",
new String[]{"Universal Plug'n'Play", "/lan.png"},
new String[]{"Network streams", "/lan.png"}), gbc);
options.add(new ConfigPane("Internet",
new String[]{"Podcasts", "/podcast.png"},
new String[]{"Assemblee Noationale", "/assembleenationale.png"},
new String[]{"Free Music Charts", "/fmc.png"},
new String[]{"Freebox TV", "/network.png"},
new String[]{"Icecast Radio Directory", "/icecast.png"},
new String[]{"Jamendo Selections", "/jamendo.png"},
new String[]{"Channels", "/metachannels.png"}
), gbc);
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
frame.setLayout(new GridBagLayout());
frame.add(new JScrollPane(options), gbc);
gbc.weighty = 1;
gbc.gridy++;
frame.add(new JPanel(), gbc);
gbc.gridx++;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.gridheight = GridBagConstraints.REMAINDER;
frame.add(new JPanel(), gbc);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class ConfigPane extends JPanel {
private JLabel title;
public ConfigPane(String name, String[]... options) {
setLayout(new GridBagLayout());
title = new JLabel(name);
title.setFont(title.getFont().deriveFont(Font.BOLD));
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.anchor = GridBagConstraints.WEST;
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(1, 1, 1, 1);
add(title, gbc);
for (String[] option : options) {
System.out.println(option[0]);
JLabel lblOption = new JLabel(option[0]);
lblOption.setIcon(new ImageIcon(getClass().getResource(option[1])));
add(lblOption, gbc);
}
}
}
}
Of course, you'll need to know when the user clicks on each option and update the main screen accordingly...
Related
Is it possible to create asymmetrical layouts (as opposed to square layouts) in Java Swing ? I'm thinking of something like this:
Is this achievable with any layout manager ? If not, I'd be interested in an explanation, too.
The short answer is, yes, the long answer is some what more complicated.
To start with, I'd be using GridBagLayout as my primary choice of layout manager, but I might consider GridLayout and BorderLayout as additional options. The point is, you want to break down your layout into manageable chunks of functionality and figure out the best solution to solve it's particular problems. You then want to piece together these individual elements back into a large picture, using the layout managers most appropriate to solve the problem each piece presents.
I'd just like to say that your basic layout screams JTable to me.
If, however, you're interested in a non-rectangular window, then it becomes somewhat more difficult, mostly because Java doesn't support decorated transparent windows (ie, windows with native frames)
If not, I'd be interested in an explanation, too
Okay, this is some what more complicated, but, it basically comes down to the fact that everything painted on the screen is contained in a, rectangular bounding box. This box was filled with a background color and the content was painted onto it.
This was done for efficiency, because everything behind this bounding box doesn't need to be painted.
As hardware became faster and rendering pipelines took more advantage of higher end libraries, like DirectX and OpenGL, it became possible to start dealing with opacity across a broader spectrum of the system, such as individual windows.
So, even when you see that really cool, curvy, funky looking UI, it's contained within a rectangular bounding box, which is transparent :/
This is pretty basic graphics concepts. Remember, it's much easier and faster to calculate a rectangular bound box (intersections/hit detection/etc) then a non-rectangular one
Per-pixel alpha is actually rather intensive to perform, which is another reason it wasn't original used at a OS/every day level, the system resources could be better used for other things
Runnable Example
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.LineBorder;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setUndecorated(true);
frame.setBackground(new Color(0, 0, 0, 0));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new MainPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class MainPane extends JPanel {
public MainPane() {
setOpaque(false);
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 0.5;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.anchor = GridBagConstraints.NORTH;
add(new FieldsPane(), gbc);
gbc.gridx++;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
add(new JScrollPane(new JTextArea(20, 20)), gbc);
}
}
public class FieldsPane extends JPanel {
private JPanel fields;
private JLabel filler;
public FieldsPane() {
setBorder(new LineBorder(Color.GRAY));
fields = new JPanel(new GridBagLayout());
filler = new JLabel();
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weighty = 1;
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
fields.add(filler, gbc);
addFields(new JLabel("Col1"), new JLabel("Col2"), new JLabel("Col3 "));
addFields(new JTextField(10), new JTextField(10), new JTextField(10));
setLayout(new GridBagLayout());
gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
add(fields, gbc);
JPanel buttons = new JPanel(new GridBagLayout());
JButton add = new JButton("Add");
JButton remove = new JButton("Remove");
buttons.add(add);
buttons.add(remove);
gbc.gridy++;
gbc.weightx = 1;
gbc.weighty = 0;
gbc.fill = GridBagConstraints.HORIZONTAL;
add(buttons, gbc);
}
protected void addFields(JComponent col1, JComponent col2, JComponent col3) {
GridBagLayout layout = (GridBagLayout) fields.getLayout();
GridBagConstraints gbc = layout.getConstraints(filler);
fields.add(makeRow(col1, col2, col3), gbc);
gbc.gridy++;
layout.setConstraints(filler, gbc);
}
protected JPanel makeRow(JComponent col1, JComponent col2, JComponent col3) {
JPanel panel = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridy = 0;
gbc.weightx = 0.33;
gbc.fill = GridBagConstraints.HORIZONTAL;
panel.add(col1, gbc);
panel.add(col2, gbc);
panel.add(col3, gbc);
return panel;
}
}
}
So I'm trying to copy the layout of this website.
Website Pinterest Log In
Here's some what I have already done.
I'm using "null" for my layout.
I also put an actionlistener on my button which shows another frame.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Frame {
public static void main (String [] args) {
JFrame frame = new JFrame("Pinterest");
frame.setVisible(true);
frame.setSize(1300,750);
JPanel panel = new JPanel();
frame.add(panel);
JLabel name = new JLabel("Log in to Pinterest");
name.setBounds(500, 96, 300, 100);
name.setFont(new Font("Tahoma", Font.PLAIN, 28));
JTextField text1 = new JTextField(15);
text1.setBounds(500, 450, 300, 40);
JTextField text2 = new JTextField(15);
text2.setBounds(500, 350, 300, 40);
JButton button = new JButton("Log In");
button.setBounds(560,550, 200,30 );
panel.setLayout(null);
panel.add(name);
panel.add(text1);
panel.add(text2);
panel.add(button);
button.addActionListener(new Action1());
}
static class Action1 implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
JFrame frame2= new JFrame("Pinterest");
frame2.setVisible(true);
frame2.setSize(1300,750);
}}
Every time I would run this in my JCreator it would only show my frame. Then I have to maximize it to view the components but after I maximize it then minimize it doesn't hide anymore.
After I maximize the frame.
What is wrong with my code?
Does my code works on yours smoothly? does it shows?
How can I hide the first frame after clicking the button?
I'm having a hard time putting icon on the frame too.
Thanks for the help.
There are a number of basic mistakes
null layouts. Avoid using null layouts, pixel perfect layouts are an illusion within modern ui design. There are too many factors which affect the individual size of components, none of which you can control. Swing was designed to work with layout managers at the core, discarding these will lead to no end of issues and problems that you will spend more and more time trying to rectify
Making the frame visible before you've finished updating the UI. In most cases this can be fixed with revalidate, but since that causes the layout managers to recalculate their layouts, it's pointless when you're using null layouts
The simple answer is, use layout managers. The longer answer is more complicated.
You have three distinct areas, the "login with" group, the "field" group and (what I like to term) the "action" group. Each of these have there own requirements and functionality, it's best to try a seperate them if you can.
This will allow to apply functionality to each group or class which is unique to that group/class and reduce a lot of management head aches
The following examples focus on the layout, it does not focus on how you would then connect the functionality, this would be achieved simply through the use of an Observer Pattern, perhaps like ActionListener
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JSeparator;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new LoginPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class LoginPane extends JPanel {
public LoginPane() {
setBackground(Color.WHITE);
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(4, 20, 4, 20);
JLabel title = new JLabel("Log in to Pinterest");
title.setFont(title.getFont().deriveFont(Font.BOLD, 18f));
title.setBorder(new EmptyBorder(10, 0, 10, 0));
add(title, gbc);
add(new GroupPane(), gbc);
gbc.insets = new Insets(4, 0, 4, 0);
add(new JSeparator(JSeparator.HORIZONTAL), gbc);
gbc.insets = new Insets(4, 20, 4, 20);
add(new FieldPane(), gbc);
gbc.insets = new Insets(4, 0, 0, 0);
add(new ActionPane(), gbc);
}
}
public class GroupPane extends JPanel {
public GroupPane() {
setOpaque(false);
JPanel fbPane = new JPanel();
JPanel goPane = new JPanel();
JPanel twPane = new JPanel();
fbPane.setBackground(Color.RED);
goPane.setBackground(Color.BLUE);
twPane.setBackground(Color.CYAN);
fbPane.add(makeLabel("Log in with Facebook"));
goPane.add(makeLabel("Log in with Google"));
twPane.add(makeLabel("Log in with Twitter"));
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(4, 0, 4, 0);
add(fbPane, gbc);
add(goPane, gbc);
add(twPane, gbc);
}
protected JLabel makeLabel(String text) {
JLabel label = new JLabel(text);
label.setForeground(Color.WHITE);
label.setFont(label.getFont().deriveFont(Font.BOLD, 14f));
return label;
}
}
public class FieldPane extends JPanel {
private JTextField email;
private JPasswordField password;
public FieldPane() {
setOpaque(false);
email = new JTextField(10);
password = new JPasswordField(10);
email.setBackground(new Color(225, 225, 225));
password.setBackground(new Color(225, 225, 225));
Font font = email.getFont().deriveFont(Font.PLAIN, 24f);
email.setFont(font);
password.setFont(font);
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.insets = new Insets(4, 0, 4, 0);
add(email, gbc);
add(password, gbc);
JLabel label = new JLabel("Are you a business? Get started here");
label.setFont(label.getFont().deriveFont(Font.PLAIN, 10f));
gbc.insets.left = 4;
add(label, gbc);
}
}
public class ActionPane extends JPanel {
public ActionPane() {
setBorder(new EmptyBorder(10, 20, 10, 20));
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.insets = new Insets(4, 4, 4, 4);
gbc.anchor = GridBagConstraints.WEST;
add(makeLabel("Forgot your password?"), gbc);
gbc.gridy++;
add(makeLabel("Sign up now"), gbc);
gbc.gridx++;
gbc.gridy = 0;
gbc.gridheight = 2;
gbc.ipady = 10;
gbc.anchor = GridBagConstraints.EAST;
JButton login = new JButton("Log in");
add(login, gbc);
}
protected JLabel makeLabel(String text) {
JLabel label = new JLabel(text);
label.setForeground(Color.DARK_GRAY);
return label;
}
}
}
Take a look at Laying Out Components Within a Container and How to Use GridBagLayout. The LoginPane could also make use of a GridLayout, see for more details
I want to align all the JLabels to the left side of the panel. Following is my code, but it doesnt work properly, I dont know why.
JFrame frame1 = new JFrame("Register a passenger");
frame1.setVisible(true);
frame1.setSize(550, 200);
JPanel panel = new JPanel();
frame1.add(panel);
JLabel label1 = new JLabel("Name",SwingConstants.LEFT);
JLabel label2 = new JLabel("Activities",SwingConstants.LEFT);
JButton jbtReg = new JButton("Register");
panel.add(label1);
panel.add(text1);
panel.add(label2);
panel.add(text2);
panel.add(jbtReg);
Based on your example, you could use
JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));
But this will align all your components to the left.
You could also consider using a different layout manager or combination of layout managers?
Take a look at A Visual Guide to Layout Managers for more ideas
Updated
FlowLayout (which is the default layout manager for JPanel) doesn't give you a lot of options, instead consider trying to use a different layout manager or combination of layout managers, for example...
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class LayoutExample {
public static void main(String[] args) {
new LayoutExample();
}
public LayoutExample() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.WEST;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.gridx = 0;
gbc.gridy = 0;
add(new JLabel("Name:"), gbc);
gbc.gridy++;
add(new JLabel("Activity:"), gbc);
gbc.gridx++;
gbc.gridy = 0;
gbc.fill = GridBagConstraints.NONE;
add(new JTextField(10), gbc);
gbc.gridy++;
add(new JTextField(20), gbc);
gbc.gridx = 0;
gbc.gridy++;
gbc.anchor = GridBagConstraints.CENTER;
gbc.gridwidth = 2;
add(new JButton("Register"), gbc);
}
}
}
I need to build in swing a screen that is something like this image. I have a main panel and in that panel I need to add multiple columns 2 vertical columns and 3 horizontal. This columns are Jpanels. I tried to use GridLayout but I did not succeeded.
Very rarly will a single layout manager do everything you want. You want to start using compound layout managers where you can/need.
This example uses both a GridLayout and a GridBagLayout
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Insets;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;
public class BadLayout21 {
public static void main(String[] args) {
new BadLayout21();
}
public BadLayout21() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setBorder(new EmptyBorder(10, 10, 10, 10));
setLayout(new GridBagLayout());
JPanel leftPane = new JPanel(new GridLayout(2, 0, 0, 4));
leftPane.add(createPane(Color.RED));
leftPane.add(createPane(Color.RED));
JPanel leftMiddlePanel = createPane(Color.BLUE);
JPanel rightMiddlePanel = createPane(Color.BLUE);
JPanel rightPane = new JPanel(new GridLayout(2, 0, 0, 4));
rightPane.add(createPane(Color.GREEN));
rightPane.add(createPane(Color.GREEN));
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.anchor = GridBagConstraints.NORTH;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.weightx = 1;
gbc.insets = new Insets(20, 20, 0, 0);
add(leftPane, gbc);
gbc.gridx = 3;
gbc.anchor = GridBagConstraints.NORTH;
gbc.insets = new Insets(20, 0, 0, 20);
add(rightPane, gbc);
gbc.weightx = 0;
gbc.gridx = 1;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.VERTICAL;
gbc.anchor = GridBagConstraints.NORTH;
gbc.insets = new Insets(0, 0, 0, 10);
add(leftMiddlePanel, gbc);
gbc.gridx = 2;
gbc.insets = new Insets(0, 10, 0, 0);
add(rightMiddlePanel, gbc);
}
protected JPanel createPane(Color color) {
JPanel panel = new JPanel();
panel.setPreferredSize(new Dimension(25, 25));
panel.setBackground(color);
return panel;
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
}
I think it will be difficult to place all the panels directly in one big panel. Multiple solutions are possible. Like dividing the the main panel in four seperate (vertical) panels and add the final panels to those four sub-panels. Or as freak suggested, start with a border layout, and first create a left-subpanel, center-subpanel and right-subpanel, each with their own layout managers. And in those sub-panels you can place your final panels.
Although the precise purpose or goal is a little fuzzy for me right now, I hope you can use my suggesten.
I have a JFrame with four components: three JPanels and a JTabbedPane. Two panels have selectable components and are located approximately in BorderLayout.NORTH and EAST, while the JTabbedPane sits approximately in CENTER. The tabs of the TabbedPane are aligned on the bottom of the pane. I say approximately because the actual layout is done with a GridBagLayout (sorry!).
Currently, the focus traversal cycle goes like this:
Current Cycle:
1) North JPanel
2) East JPanel
3) JTabbedPane selected tab
4) JTabbedPane selected tab content
However, I'd like it to be:
Desired Cycle:
1) North JPanel
2) JTabbedPane selected tab content
3) JTabbedPane selected tab
4) East JPanel
I have tried the Vector-based FocusTraversalPolicy given by the Java Focus Guide with no luck: I couldn't get the cursor to go down into the tab panel contents.
I then looked into extending/changing the other FocusTraversalPolicy classes out there, but got nowhere with that either.
I'm fairly sure the issue is the current FocusTraversalPolicy uses component location on screen to determine the layout cycle. Technically the side panel is higher on the screen than the center tabbed pane. I'd really like to change this though. Anybody else run into this/have any insight? Thanks!!
EDIT:
Here's an SSCCE with proper layout code demonstrating the problem. Just a note: the issue is NOT the layout, as that has to stay the same.
package SO;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.JTextField;
public class ssccee7729709{
JPanel north;
JPanel north2;
JPanel east;
JTabbedPane center;
JFrame content;
void initialize() {
north = new JPanel(new FlowLayout()) {
{
this.setBackground(Color.CYAN);
}
};
north.add(new JLabel("Title panel"));
north2 = new JPanel(new FlowLayout()) {
{
this.setBackground(Color.RED);
}
};
north2.add(new JLabel("north2 Panel"));
north2.add(new JTextField(4));
north2.add(new JTextField(4));
east = new JPanel(new GridLayout(3,1)) {
{
this.setBackground(Color.BLUE);
}
};
east.add(new JButton("b1"));
east.add(new JButton("b2"));
center = new JTabbedPane(JTabbedPane.BOTTOM, JTabbedPane.WRAP_TAB_LAYOUT);
for (int i = 0; i < 2; i++) {
JPanel panel = new JPanel(new GridLayout(4,1));
panel.add(new JLabel("Panel " + i));
panel.add(new JTextField(6));
panel.add(new JTextField(6));
panel.add(new JTextField(6));
center.addTab("Tab " + i, panel);
}
content = new JFrame();
content.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
content.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
{
gbc.fill = GridBagConstraints.BOTH;
gbc.gridwidth = 4;
gbc.weightx = 1;
content.add(north, gbc);
}
{
gbc = new GridBagConstraints();
gbc.fill = GridBagConstraints.BOTH;
gbc.anchor = GridBagConstraints.PAGE_START;
gbc.gridwidth = 1;
gbc.weightx = 1;
// gbc.weighty = .1;
gbc.gridy = 1;
gbc.gridx = 1;
content.add(north2, gbc);
}
{
gbc = new GridBagConstraints();
gbc.fill = GridBagConstraints.BOTH;
gbc.gridwidth = GridBagConstraints.RELATIVE;
gbc.gridheight = GridBagConstraints.RELATIVE;
gbc.weighty = 1;
gbc.gridy = 2;
content.add(center, gbc);
}
{
gbc = new GridBagConstraints();
gbc.fill = GridBagConstraints.VERTICAL;
gbc.anchor = GridBagConstraints.SOUTHEAST;
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.gridx = 3;
gbc.gridheight = 4;
content.add(east, gbc);
}
content.setVisible(true);
content.pack();
}
public static void main(String args[]) {
ssccee7729709 so = new ssccee7729709();
so.initialize();
}
}
If you look at the source for LayoutFocusTraversalPolicy, which is the default policy, it pretty much just extends SortingFocusTraversalPolicy, which takes a Comparator<? extends Component>.
You should be able to provide your own Comparator which is an inner class and so has access to parent components, and provide appropriate comparison values by looking at themselves and their parents.
It probably wouldn't hurt to check out the source to LayoutComparator which is what LayoutFocusTraveralPolicy uses.
After cloning LayoutComparator, I had to add the following lines to the compare method:
...previous code...
int zOrder = a.getParent().getComponentZOrder(a) - b.getParent().getComponentZOrder(b);
/// added these:
if (a instanceof EastPanel) {
if (b instanceof JTabbedPane || b instanceof NorthPanel) {
return -1;
}
}
if (b instanceof EastPanel) {
if (a instanceof JTabbedPane || a instanceof NorthPanel) {
return 1;
}
}
if (horizontal) {
if (leftToRight) {
...more code...
Honestly I don't know how this works...the mechanism of using compare to order components is strange to me...but this works, so... hooray magic!