Trying to learn how to do some elegant and more advanced JFrame layouts. I'm trying to make something I thought would be rather simple, but I'm having some difficulty with it. As opposed to messing around for hours (even though I already have) trying to get the layout to work, I thought I would ask what the best convention for a the layout I'm about to describe would be.
The Layout
Basically, I want 2 columns, but the first column to be wider than the second column. Within the first column there will be just one cell, and that cell will have a JLabel with an icon attached to it, centered in the cell. The second column will have 4 rows, each with a JComponent in it (doesn't matter what). Another key is that every component in the JFrame retains its preferred size, and doesn't stretch to fit its cell or what have you.
Here's a picture of the desired layout:
So far I've thought of doing this a couple different ways:
A BorderLayout, with the JLabel-icon in the center, and a GridLayout/GridBagLayout controlling the rest.
A GridBagLayout 4x4 where the JLabel-icon takes up a 3x4 area, in theory giving it 75% of the space.
Neither give me the results I'm looking for. Thoughts/Suggestions? All help and suggestions are greatly appreciated.
For my own sanity, I would normally separate the individual elements of the layout. This can, sometimes, simplify the process as you only need to focus on the areas of the layout that are important (to each section).
The following example uses a single layout just to demonstrate the power of GridBagLayout
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class AdvancedLayout {
public static void main(String[] args) {
new AdvancedLayout();
}
public AdvancedLayout() {
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 {
private JLabel image;
private JButton button;
private JLabel label;
private JComboBox comboBox;
private JButton otherButton;
public TestPane() {
setLayout(new GridBagLayout());
image = new JLabel();
button = new JButton("A button");
label = new JLabel("A label");
comboBox = new JComboBox();
otherButton = new JButton("Other");
try {
image.setIcon(new ImageIcon(ImageIO.read(new File("/path/to/a/image"))));
} catch (IOException ex) {
ex.printStackTrace();
}
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 0.6666666666666667;
gbc.weighty = 1f;
gbc.gridheight = GridBagConstraints.REMAINDER;
add(image, gbc);
gbc.gridheight = 1;
gbc.gridx++;
gbc.weightx = 0.3333333333333333f;
gbc.weighty = 0.25f;
add(button, gbc);
gbc.gridy++;
add(label, gbc);
gbc.gridy++;
add(comboBox, gbc);
gbc.gridy++;
add(otherButton, gbc);
}
}
}
This could, just as easily, be used with two JPanels, one been for the image and one for the options. This would remove the need to use gridheight...
Your first suggestion is reasonable.
The label can be centered both vertically and horizontally.
For the GridLayout the trick would be to add each component to a JPanel that uses a GridBagLayout with the default gridbag constraints. Then add the panel to the GridLayout. Now, if the frame does resize, the panel will grow, but not the component on the panel and the component will be centered in the panel.
Instead of using the GridLayout with other sub panels, you can also use a vertical BoxLayout and add "glue" before/after every component. Not that with this approach you will need to make sure every component uses an alignment that is centered. Also, you may need to set the maximum size of some components equal to the preferred size of the component so it doesn't grow when space is available.
Related
So I have been trying to come up with a good layout manager that will enable me to put multiple components in a scrollable panel with different sizes. The only one I found was gridlayout, but it forces the same size.
here is the current code I have:
package main;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main {
public static void main(String[] args) {
// Create and set up a frame window
JFrame frame = new JFrame("Layout");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Define the panel to hold the components
JPanel panel = new JPanel(new GridLayout(0, 1, 0, 0));
panel.setPreferredSize(new Dimension(500, 800));
for (int i = 0; i < 20; i++) {
JButton button = new JButton("Button " + i);
button.setPreferredSize(new Dimension(50, 100 + (i * 10)));
panel.add(button);
}
// Add the panel and set the window to be visible
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
}
I also do know about GridBagLayout, but I do want a layout that wouldn't require me to enter the numbers manually.
I also do know about GridBagLayout, but I do want a layout that wouldn't require me to enter the numbers manually.
You can specify:
constraint.gridWidth = GridBagConstraints.REMAINDER;
and each component will be placed on a new row.
Or you can use a BoxLayout, as I suggested in my comment, and not worry about constraints.
Read the tutorial. The constraints for the GridBagLayout are explained in more detail.
I'm trying to implement a feature that (in my test project) once a button is pressed, it adds a random number to my JPanel. (I use the layouts I have because in my real program, I have more items inside and it displays correctly). But I need my program to recognize when the scrollbar is visible (which I implemented that, but it's a little delay. What I mean by delay is I push the button to add a number, if the scrollbar becomes visible nothing happens. But then the next time I press the button it shifts over like I want). The other problem I have (the one I'm focused on now) is that when I dynamically change the size of the JPanel, if the scrollbar is visible, I have it set to change the width to my width - the width of the scrollbar. But It seems like when the scrollbar is visible, the newly inputted number moves over twice the scrollbar width instead of just once. I've been at this part of my program for over a day and can't figure it out. I'll add my full code and some screenshots.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.UIManager;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class Main {
JFrame frame;
JPanel topPanel;
JPanel memoryPanel;
JScrollPane sPane;
JButton button;
ArrayList<Integer> list = new ArrayList<>();
boolean isVScrollVisible = false;
int scrollBarSize = 0;
public class MyChangeListener implements ChangeListener {
#Override
public void stateChanged(ChangeEvent e) {
isVScrollVisible = (sPane.getVerticalScrollBar().isVisible());
}
}
public class ButtonListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
Random random = new Random();
int r = random.nextInt(10);
list.add(r);
int n;
if (isVScrollVisible) {
n = scrollBarSize;
} else {
n = 0;
}
JPanel nextPanel = new JPanel();
nextPanel.setName("" + r);
nextPanel.setForeground(Color.BLACK);
nextPanel.setPreferredSize(new Dimension(200 - n, 55));
nextPanel.setMinimumSize(new Dimension(200 - n, 55));
nextPanel.setMaximumSize(new Dimension(200 - n, 55));
JPanel labelPanel = new JPanel();
labelPanel.setLayout(new BorderLayout());
JLabel label = new JLabel();
label.setText("" + r);
label.setPreferredSize(new Dimension(200 - n, 55));
label.setMinimumSize(new Dimension(200 - n, 55));
label.setMaximumSize(new Dimension(200 - n, 55));
label.setHorizontalAlignment(JLabel.RIGHT);
label.setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 17));
label.setFont(new Font("Sans-Serif", Font.BOLD, 20));
labelPanel.add(label);
nextPanel.add(labelPanel, BorderLayout.LINE_START);
for (int i = 0; i < memoryPanel.getComponents().length; i++) {
memoryPanel.getComponent(i).setPreferredSize(new Dimension(200 - n, 55));
memoryPanel.getComponent(i).revalidate();
memoryPanel.getComponent(i).repaint();
}
memoryPanel.add(nextPanel, 0);
memoryPanel.revalidate();
memoryPanel.repaint();
sPane.revalidate();
sPane.repaint();
}
}
public Main() {
frame = new JFrame();
topPanel = new JPanel();
memoryPanel = new JPanel();
memoryPanel.setLayout(new BoxLayout(memoryPanel, BoxLayout.Y_AXIS));
sPane = new JScrollPane(memoryPanel, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
sPane.setPreferredSize(new Dimension(200, 300));
sPane.getViewport().addChangeListener(new MyChangeListener());
scrollBarSize = ((Integer)UIManager.get("ScrollBar.width")) + 1;
button = new JButton("Add Random Number");
button.addActionListener(new ButtonListener());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
topPanel.add(button);
frame.add(topPanel, BorderLayout.PAGE_START);
frame.add(sPane, BorderLayout.CENTER);
frame.setResizable(false);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
new Main();
}
}
I need them to look exactly the same. Before I had the code I have now, the scrollbar would appear over the numbers which looked ugly. And the reason I have the frame resizable false is because In my real program I hard coded all the sizes, which in the future I will calculate the correct sizes based on the size of the frame, so right now setting resizable to true is out of the question. Any suggestions on what to do?
This is what I'm trying to accompolish.
Get rid of all the logic that sets the preferred/minimum/maximum sizes. Each component knows what its size should be. Each layout manager will in turn know what the preferred size of the panel should be. Let the layout manager use the information to do its job.
The basic logic for dynamically adding components is:
panel.add(...);
panel.revalidate();
panel.repaint();
Then the scrollbars will appear automatically when required. There is no need for listeners or anything.
Edit:
The reason I set all the sizes is because If I take them out then everything appears centered
Learn how to use layout managers properly and effectively.
For example when using a BoxLayout you can control the alignment of components by using:
component.setAlignmentX(JLabel.RIGHT_ALIGNMENT);
and the component will be aligned to the right edge of the space available to the component.
When using a JLabel you may also need to set a property on the JLabel to align the text to the right edge of the label. Read the JLabel API for the appropriate method.
I have created a simple program that has 1 JLabel that says Would you like to continue and 2 JButtons one that says yes and one that says no.
I'm using GridBaGLayout to organize the JPanel / JFrame. My program compiles and runs just fine but GridBagLayout Centers all my components in the center of the JFrame. Since I'm new to swing can someone show me how its may be possible to align all my components to the top left of the JFrame?
It might not be a real answer, but anyway: stop using GridBagLayout. It has so many pitfalls and is so brittle to use, so please don't use it.
Use a better alternative such as MigLayout, and learn that. Don't bother learning any of Java's default Layout Managers, except if you really, really need to.
An example using MigLayout:
JPanel panel = new JPanel(new MigLayout("","",""));
panel.add(myJButton1, "wrap");
panel.add(myJButton2, "wrap");
panel.add(myJButton3, "wrap");
panel.add(myJButton4, "wrap");
panel.add(myJButton5, "wrap");
panel.add(myJButton6, "wrap");
There's a couple of ways you could do it, you could add all the components to another container first and then layout that container in your container, but the basic principle would remain...
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.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();
}
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.weightx = 1;
gbc.anchor = GridBagConstraints.WEST;
gbc.gridwidth = GridBagConstraints.REMAINDER;
for (int index = 0; index < 10; index++) {
add(new JButton("Test"), gbc);
}
gbc.weighty = 1;
add(new JLabel(), gbc);
}
}
}
Basically, this adds a "hidden" component to the last row, which wants to use up the remaining space of the container, forcing the components to the top/left corner of the container
So here is my basic template for Tic Tac Toe:
package myProjects;
import javax.swing.BorderFactory;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JLabel;
import javax.swing.JButton;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.event.*;
public class SecondTickTacToe extends JFrame{
public JPanel mainPanel;
public static JPanel[][] panel = new JPanel[3][3];
public static void main(String[] args) {
new SecondTickTacToe();
}
public SecondTickTacToe(){
this.setSize(310, 400);
this.setTitle("Tic Tac Toe");
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
mainPanel = new JPanel();
for(int row=0; row<3; row++){
for(int column=0; column<3; column++){
int top=0;
int bottom=0;
int left=0;
int right=0;
panel[row][column] = new JPanel();
panel[row][column].addMouseListener(new Mouse());
panel[row][column].setPreferredSize(new Dimension(90, 90));
panel[row][column].setBackground(Color.GREEN);
if(column==0||column==1)
right = 5;
if(column==1||column==2)
left = 5;
if(row==0||row==1)
bottom = 5;
if(row==1||row==2)
top = 5;
panel[row][column].setBorder(BorderFactory.createMatteBorder(top, left, bottom, right, Color.BLACK));
addItem(panel[row][column], row, column);
}
}
this.add(mainPanel);
this.setVisible(true);
}
private void addItem(JComponent c, int x, int y){
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.weightx = 100.0;
gbc.weighty = 100.0;
gbc.fill = GridBagConstraints.NONE;
mainPanel.add(c, gbc);
}
}
class Mouse extends MouseAdapter{
public void mousePressed(MouseEvent e){
if(e.getSource() instanceof JPanel)
((JPanel)e.getSource()).setBackground(Color.BLUE);
}
}
(You'll have to run the program to see what I'm talking about)
So here is my question:
Is there a way that I can fill in the space between the borders of the JPanels? I want it to be solid. Making the panels bigger doesn't seem to work, and making the border size bigger doesn't seem to do anything either. Does anyone know how to make this work? (My end goal is to make the borders look like a solid tic tac toe template)
mainPanel = new JPanel();
The default layout for a JPanel is a FlowLayout. By default a FlowLayout leaves a 5 pixel gap between all components. If you don't want this gap then you need to change the layout. Read the FlowLayout API and you will find the constructor that allows you to specify a 0 gap.
However, using a FlowLayout may not be the best layout. A GridLayout is the easier layout to use for row and columns. I suggest you read the section from the Swing tutorial on How to Use Grid Layout for more information and examples. There will be no need for your addItem(...) method. When you create the GridLayout with the proper row/columns the components will automatically wrap to a new row so you just add the component to the panel.
mainPanel.add(c, gbc);
By the way, specifying a GridBagConstraint does nothing unless the panel is actually using a GridBagLayout, which is not.
I will place these buttons in the center of the frame and above each other, like this.
BUTTON
BUTTON
BUTTON
I've searched multiple topics on this forum but everything I tried didn't work for so far. I hope that somebody has the solution.
This is my code for so far:
package ípsen1;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
public class Paneel extends JPanel implements ActionListener {
Image achtergrond;
private JButton spelHervatten;
private JButton spelOpslaan;
private JButton spelAfsluiten;
public Paneel(){
//buttons
spelHervatten = new JButton("Spel hervatten");
spelHervatten.setPreferredSize(new Dimension(380, 65));
spelOpslaan = new JButton("Spel opslaan");
spelOpslaan.setPreferredSize(new Dimension(380, 65));
spelAfsluiten = new JButton("Spel afsluiten");
spelAfsluiten.setPreferredSize(new Dimension(380, 65));
//object Paneel luistert naar button events
spelAfsluiten.addActionListener(this);
add (spelHervatten);
add (spelOpslaan);
add (spelAfsluiten);
}
public void paintComponent(Graphics g) {
//achtergrond afbeelding zetten
achtergrond = Toolkit.getDefaultToolkit().getImage("hout.jpg");
//screensize
g.drawImage(achtergrond, 0,0, 1024,768,this);
}
//actie na klik op button
public void actionPerformed(ActionEvent e) {
if(e.getSource() == spelAfsluiten){
System.out.println("Spel afsluiten");
System.exit(0);
}
}
}
You could use a GridBagLayout
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.fill = GridBagConstraints.HORIZONTAL;
add(new JButton("Button"), gbc);
add(new JButton("Button"), gbc);
add(new JButton("Button"), gbc);
add(new JButton("Button"), gbc);
See How to Use GridBagLayout for more details
A BoxLayout might be what you're after. You can specify that you want to add components along the y-axis in the constructor for that particular layout manager.
You could add this line to the constructor of your Paneel class.
this.setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
As for center-aligning everything, I don't know if it's good practice but you can set the horizontal alignment for each of your buttons individually. Example:
spelHervatten.setAlignmentX(CENTER_ALIGNMENT);
Uses a GridLayout for a single column of buttons of equal width.
The buttons stretch as the window's size increases. To maintain the button size, put the GridLayout as a single component into a GridBagLayout with no constraint. It will be centered.
The size of the buttons is increased by setting a margin.
import java.awt.*;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
/*
* Uses a GridLayout for a single column of buttons of equal width.
* The buttons stretch as the window's size increases. To maintain
* the button size, put the GridLayout as a single component into a
* GridBagLayout with no constraint. It will be centered.
*/
public class CenteredSingleColumnOfButtons {
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
// the GUI as seen by the user (without frame)
JPanel gui = new JPanel(new GridLayout(0,1,10,10));
gui.setBorder(new EmptyBorder(20,30,20,30));
String[] buttonLabels = {
"Spel hervatten",
"Spel opslaan",
"Spel afsluiten"
};
Insets margin = new Insets(20,150,20,150);
JButton b = null;
for (String s : buttonLabels) {
b = new JButton(s);
b.setMargin(margin);
gui.add(b);
}
JFrame f = new JFrame("Centered Single Column of Buttons");
f.add(gui);
// Ensures JVM closes after frame(s) closed and
// all non-daemon threads are finished
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
// See http://stackoverflow.com/a/7143398/418556 for demo.
f.setLocationByPlatform(true);
// ensures the frame is the minimum size it needs to be
// in order display the components within it
f.pack();
f.setMinimumSize(f.getSize());
// should be done last, to avoid flickering, moving,
// resizing artifacts.
f.setVisible(true);
System.out.println(b.getSize());
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency
SwingUtilities.invokeLater(r);
}
}
I thought there is no way to do that.
You should get size of Panel/Frame then calculate manually to find to center position for your button.
Rephrased some parts:
You might want to try to put the buttons in JFrame's "wind direction"-style BorderLayout:
http://www.leepoint.net/notes-java/GUI/layouts/20borderlayout.html
Just create a block in the CENTER with one EAST and WEST block with a certain size around it. Then insert the buttons inside of the center block. If you don't want them to be the full size, just add another EAST and WEST.