I'm trying to think of the best layout manager to achieve the picture below. I know absolute positioning is what I am used to, but I can't get the background image using this. GridBagLayout is excellent, but horrifically hard when ever I try I get a separate image for each grid.
Does anyone know an easy way out of this, or easy code to achieve the following?
There are several ways to do it. These are what I can think of at the moment:
Create a subclass of JComponent.
Override the paintComponent(Graphics g) method to paint the image that you want to display.
Set the content pane of the JFrame to be this subclass.
Some sample code:
class ImagePanel extends JComponent {
private Image image;
public ImagePanel(Image image) {
this.image = image;
}
#Override
protected void paintComponent(Graphics g) {
g.drawImage(image, 0, 0, null);
}
}
// elsewhere
BufferedImage myImage = ImageIO.read(...);
JFrame myJFrame = new JFrame("Image pane");
myJFrame.setContentPane(new ImagePanel(myImage));
Note that this code does not handle re-sizing the image to fit the JFrame, if that's what you wanted.
There are a number of ways you can achieve this.
The simplest might be to just use what's already available...
If you don't need the background to be scaled at run-time (ie you can get away with a non-resizable window), simply using a JLabel as the primary container could make your life significantly easier.
public class LabelBackground {
public static void main(String[] args) {
new LabelBackground();
}
public LabelBackground() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new LoginPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class LoginPane extends JLabel {
public LoginPane() {
try {
setIcon(new ImageIcon(ImageIO.read(getClass().getResource("/background.jpg"))));
} catch (IOException ex) {
ex.printStackTrace();
}
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.EAST;
gbc.insets = new Insets(2, 2, 2, 2);
gbc.gridx = 0;
gbc.gridy = 0;
JLabel nameLabel = new JLabel("Name: ");
nameLabel.setForeground(Color.WHITE);
JLabel passwordLabel = new JLabel("Password: ");
passwordLabel.setForeground(Color.WHITE);
add(nameLabel, gbc);
gbc.gridy++;
add(passwordLabel, gbc);
gbc.anchor = GridBagConstraints.WEST;
gbc.gridx++;
gbc.gridy = 0;
add(new JTextField(20), gbc);
gbc.gridy++;
add(new JTextField(20), gbc);
gbc.gridy++;
gbc.insets = new Insets(10, 2, 2, 2);
gbc.anchor = GridBagConstraints.EAST;
add(new JButton("Submit"), gbc);
}
}
}
Updated with example of left alignment
At the end of the constructor, add...
JPanel filler = new JPanel();
filler.setOpaque(false);
gbc.gridx++;
gbc.weightx = 1;
add(filler, gbc);
You might like to take a look at How to use GridBagLayout for more details
Related
I've seen two other posts on stackoverflow about this and in both, the solutions use setConstraints(myComponent, anotherConstraint) which doesn't even come up as an available method when I try to use it in java.
want to change an Inset in a gridbag layout dynamically
Change the component weight dynamically in GridBagLayout
How else could I change the weightx of a component after a button press?
The actual problem is that I have two components at the bottom of the screen and I need to set one of the components to be the max width of the screen after a button press.
I couldn't get setConstraints() to work..
Then it seems the code was wrong. From the fact the RHS of the red panel neatly aligns with the LHS of the Articuno label I suspect that the grid bag cell containing the red panel does not span more than one column, and currently entirely fills that column.
There could be other reasons, but short a minimal reproducible example I won't speculate further.
Here is a simplified example showing how to do it. Note that it was necessary to call revalidate() before the changes could be seen.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
import java.awt.image.BufferedImage;
public class FullWidthToggle {
private JComponent ui = null;
FullWidthToggle() {
initUI();
}
public final void initUI() {
if (ui != null) {
return;
}
GridBagConstraints gbc = new GridBagConstraints();
GridBagLayout gbl = new GridBagLayout();
ui = new JPanel(gbl);
ui.setBorder(new EmptyBorder(4, 4, 4, 4));
BufferedImage image = new BufferedImage(
160, 20, BufferedImage.TYPE_INT_RGB);
gbc.insets = new Insets(5, 5, 5, 5);
ui.add(new JLabel(new ImageIcon(image)), gbc);
final JCheckBox checkBox = new JCheckBox("Full Width");
gbc.gridx = 1;
gbc.anchor = GridBagConstraints.LINE_START;
ui.add(checkBox, gbc);
final JLabel label = new JLabel("Am I full width?");
label.setBorder(new LineBorder(Color.RED, 2));
gbc.gridx = 0;
gbc.gridy = 1;
gbc.gridwidth = 2;
ui.add(label, gbc);
ActionListener actionListener = (ActionEvent e) -> {
if (checkBox.isSelected()) {
gbc.fill = GridBagConstraints.HORIZONTAL;
} else {
gbc.fill = GridBagConstraints.NONE;
}
gbl.setConstraints(label, gbc);
ui.revalidate(); // <- important!
};
checkBox.addActionListener(actionListener);
}
public JComponent getUI() {
return ui;
}
public static void main(String[] args) {
Runnable r = () -> {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception useDefault) {
}
FullWidthToggle o = new FullWidthToggle();
JFrame f = new JFrame(o.getClass().getSimpleName());
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setContentPane(o.getUI());
f.pack();
f.setMinimumSize(f.getSize());
f.setVisible(true);
};
SwingUtilities.invokeLater(r);
}
}
Is it possible to line up swing components?
The components are in separate panels which both use flow layout. These two panels are in another panel which is using a grid layout.
As you can see there is a subtle difference and I find it annoying. I know that all of the jlabels [the rectangles in blue/purple all have the same size, so i think it might be because of the '+' and '*', but I'm not sure because the left sides of the first two boxes aren't lined up.
the panels
JPanel panel2 = new JPanel(new GridLayout(4, 1));
JPanel panel2a = new JPanel(new FlowLayout());
JPanel panel2b = new JPanel(new FlowLayout());
the first two rectangles (purple)
add1 = new JLabel("", JLabel.CENTER);
add1.setTransferHandler(new TransferHandler("text"));
add1.setBorder(b2);
add2 = new JLabel("", JLabel.CENTER);
add2.setTransferHandler(new TransferHandler("text"));
add2.setBorder(b2);
the two blue rectangles
textFieldA = new JTextField();
textFieldA.setHorizontalAlignment(JTextField.CENTER);
textFieldA.setEditable(false);
textFieldA.setBorder(new LineBorder(Color.blue));
textFieldM = new JTextField();
textFieldM.setHorizontalAlignment(JTextField.CENTER);
textFieldM.setEditable(false);
textFieldM.setBorder(new LineBorder(Color.blue));
the + and *
opA = new JLabel("+", JLabel.CENTER);
opS = new JLabel("*", JLabel.CENTER);
Showing that the rectangles are the same size
Dimension d = card1.getPreferredSize();
int width = d.width + 100;
int height = d.height + 50;
add1.setPreferredSize(new Dimension(width, height));
add2.setPreferredSize(new Dimension(width, height));
mult1.setPreferredSize(new Dimension(width, height));
mult2.setPreferredSize(new Dimension(width, height));
textFieldA.setPreferredSize(new Dimension(width, height));
textFieldM.setPreferredSize(new Dimension(width, height));
Adding to the panels
panel2a.add(add1);
panel2a.add(opA);
panel2a.add(add2);
panel2a.add(enterA);
panel2a.add(textFieldA);
panel2c.add(mult1);
panel2c.add(opM);
panel2c.add(mult2);
panel2c.add(enterM);
panel2c.add(textFieldM);
panel2.add(panel2a);
panel2.add(panel2c);
AFAIU this could be achieved using GroupLayout. This layout would require 5 horizontal groups and 2 vertical groups.
See How to Use GroupLayout for examples (including discussion of that image).
See also this answer for an MCVE.
Cross container layout management isn't really possible (or at least I've never seen a layout manager that does it).
You can, however, think carefully about your layout requirements and produce some interesting effects using compound components and layout managers...
public class TestLayout {
public static void main(String[] args) {
new TestLayout();
}
public TestLayout() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
} catch (UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridLayout(2, 0));
frame.add(new CalculatePane("+"));
frame.add(new CalculatePane("x"));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class CalculatePane extends JPanel {
public CalculatePane(String operator) {
setLayout(new GridBagLayout());
Font font = UIManager.getFont("TextField.font").deriveFont(Font.BOLD, 24);
JTextField field1 = new JTextField(2);
JTextField field2 = new JTextField(2);
JTextField field3 = new JTextField(2);
field1.setFont(font);
field2.setFont(font);
field3.setFont(font);
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.insets = new Insets(2, 2, 2, 2);
gbc.fill = GridBagConstraints.BOTH;
add(field1, gbc);
gbc.gridx++;
add(new JLabel(operator), gbc);
gbc.gridx++;
add(field2, gbc);
gbc.gridx++;
gbc.fill = GridBagConstraints.HORIZONTAL;
add(new JButton("="), gbc);
gbc.fill = GridBagConstraints.BOTH;
gbc.gridx++;
add(field3, gbc);
}
}
}
I am kind of new to Java Programming and I am trying to make a window that contains two buttons and a text area, as seen in the image below.
The problem I encountered though was positioning the components. I tried using GridLayout and separating the window into 9 rows and 16 cells, but then found I couldn't make components occupy more than a cell. I know I should be using GridBagLayout but I don't know how exactly. Help would be appreciated. :)
You have a number of choices. Instead of trying to layout the whole component in one, try using a compound layout, where by you layout sections of the UI in separate panes and focus on the individual requirements of each section...
public class TestLayout11 {
public static void main(String[] args) {
new TestLayout11();
}
public TestLayout11() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
} catch (UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new ExamplePane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
protected class ExamplePane extends JPanel {
public ExamplePane() {
setLayout(new GridBagLayout());
JPanel buttonPane = new JPanel(new GridBagLayout());
JButton btnOkay = new JButton("Ok");
JButton btnCancel = new JButton("Cancel");
JTextArea textArea = new JTextArea(5, 20);
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.anchor = GridBagConstraints.CENTER;
buttonPane.add(btnOkay, gbc);
gbc.gridy++;
gbc.insets = new Insets(50, 0, 0, 0);
buttonPane.add(btnCancel, gbc);
gbc.gridx = 0;
gbc.gridy = 0;
gbc.insets = new Insets(100, 100, 100, 100);
add(buttonPane, gbc);
gbc.insets = new Insets(150, 100, 150, 100);
gbc.gridx++;
gbc.gridy = 0;
gbc.fill = GridBagConstraints.BOTH;
add(new JScrollPane(textArea), gbc);
}
}
}
My code has a JPanel that contains three collapsible JPanels. The outer JPanel uses the BoxLayout to stack the three JPanels vertically. However, when I collapse a JPanel, the top JPanel will always expands to fill the region (even if I setMaximumSize() or such), whereas I want the lower JPanels to expand upward. It is generally glitchy. I was looking at the GridBagLayout, would that be more suitable for this sort of endeavor?
Thanks.
This is a VB image of what I dream about in my wildest dreams (images with title "Vertical Panels"):
http://www.codeproject.com/KB/cpp/CollapsiblePanelVB.aspx
I don't know what a collapsable panel is. Does it collapse all the way to 0, or does is have a minimum height?
If you manage the maximum size to always equal the preferred size then you should be able to use a BoxLayout. Just make sure you also use:
panel.add( Box.createVerticalGlue() );
at the bottom of your panel to allow the extra space to be used by the glue.
It would take me forever to cut out a compilable snippet from the 500 lines of garbage sprawled out before me.
And that is the reason for creating a SSCCE and forgetting about your garbage code. All you need is a panel with 3 collapsable panels. Then you add a button to collapse the panel and see what happens. Its better to start with demo code then write 500 lines of code and find out it doesn't work.
I strongly suggest MigLayout. It's very powerful and very easy to use. It's also widely used.
or old classic based on GridBagLayout
import java.awt.*;
import java.awt.event.*;
import java.awt.font.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
public class ExpansiblePanel {
public static void main(String[] args) {
CollapsablePanel cp = new CollapsablePanel("test", buildPanel());
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.getContentPane().add(new JScrollPane(cp));
f.setPreferredSize(new Dimension(360, 200));
f.setLocation(150, 150);
f.pack();
f.setVisible(true);
}
public static JPanel buildPanel() {
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(2, 1, 2, 1);
gbc.weightx = 1.0;
gbc.weighty = 1.0;
JPanel p1 = new JPanel(new GridBagLayout());
gbc.gridwidth = GridBagConstraints.RELATIVE;
p1.add(new JButton("button 1"), gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
p1.add(new JButton("button 2"), gbc);
gbc.gridwidth = GridBagConstraints.RELATIVE;
p1.add(new JButton("button 3"), gbc);
gbc.gridwidth = GridBagConstraints.REMAINDER;
p1.add(new JButton("button 4"), gbc);
p1.setBackground(Color.blue);
return p1;
}
private ExpansiblePanel() {
}
}
class CollapsablePanel extends JPanel {
private static final long serialVersionUID = 1L;
private boolean selected;
private JPanel contentPanel_;
private HeaderPanel headerPanel_;
private class HeaderPanel extends JPanel implements MouseListener {
private static final long serialVersionUID = 1L;
private String text_;
private Font font;
private BufferedImage open, closed;
final int OFFSET = 30, PAD = 5;
HeaderPanel(String text) {
addMouseListener(this);
text_ = text;
font = new Font("sans-serif", Font.PLAIN + Font.BOLD, 12);
// setRequestFocusEnabled(true);
setPreferredSize(new Dimension(200, 25));
setBackground(Color.black);
setForeground(Color.red);
int w = getWidth();
int h = getHeight();
/*try {
open = ImageIO.read(new File("images/arrow_down_mini.png"));
closed = ImageIO.read(new File("images/arrow_right_mini.png"));
} catch (IOException e) {
e.printStackTrace();
}*/
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int h = getHeight();
/*if (selected)
g2.drawImage(open, PAD, 0, h, h, this);
else
g2.drawImage(closed, PAD, 0, h, h, this);
*/ // Uncomment once you have your own images
g2.setFont(font);
FontRenderContext frc = g2.getFontRenderContext();
LineMetrics lm = font.getLineMetrics(text_, frc);
float height = lm.getAscent() + lm.getDescent();
float x = OFFSET;
float y = (h + height) / 2 - lm.getDescent();
g2.drawString(text_, x, y);
}
#Override
public void mouseClicked(MouseEvent e) {
toggleSelection();
}
#Override
public void mouseEntered(MouseEvent e) {
}
#Override
public void mouseExited(MouseEvent e) {
}
#Override
public void mousePressed(MouseEvent e) {
}
#Override
public void mouseReleased(MouseEvent e) {
}
}
CollapsablePanel(String text, JPanel panel) {
super(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(1, 3, 0, 3);
gbc.weightx = 1.0;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.gridwidth = GridBagConstraints.REMAINDER;
selected = false;
headerPanel_ = new HeaderPanel(text);
setBackground(Color.orange);
contentPanel_ = panel;
add(headerPanel_, gbc);
add(contentPanel_, gbc);
contentPanel_.setVisible(false);
JLabel padding = new JLabel();
gbc.weighty = 1.0;
add(padding, gbc);
}
public void toggleSelection() {
selected = !selected;
if (contentPanel_.isShowing()) {
contentPanel_.setVisible(false);
} else {
contentPanel_.setVisible(true);
}
revalidate();
headerPanel_.repaint();
}
}
So I just stumbled across placement of tabs in a JTabbedPane to the right and left (i.e. setTabPlacement(JTabbedPane.RIGHT)) which I love the look of. What I need is to utilize the space this leaves beneath the tabs. I currently have a column of JButtons, but they get pushed to the side, leaving a lot of blank space.
Any thoughts on how to do this? Some kind of custom overlay or something?
Here's a screenshot. In the code I basically have one horizontally aligned Box, with the JTabbedPane over a JTree, then the column of buttons after that.
boxOfEverything.add(tabbedPane);
boxOfEverything.add(boxColumnButtons);
Screenshot here.
I made this community wiki because this answer is not mine. #cheesecamera seems to have posted the same question on another forum and got an answer there. I copied the answer so that people coming here looking for an answer can get an answer.
The idea is to use swing's glasspane.
import java.awt.*;
import javax.swing.*;
public class RightTabPaneButtonPanel {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new RightTabPaneButtonPanel().makeUI();
}
});
}
public void makeUI() {
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.setTabPlacement(JTabbedPane.RIGHT);
JPanel panel = new JPanel(new GridLayout(0, 1));
for (int i = 0; i < 3; i++) {
JPanel tab = new JPanel();
tab.setName("tab" + (i + 1));
tab.setPreferredSize(new Dimension(400, 400));
tabbedPane.add(tab);
JButton button = new JButton("B" + (i + 1));
button.setMargin(new Insets(0, 0, 0, 0));
panel.add(button);
}
JFrame frame = new JFrame();
frame.add(tabbedPane);
frame.pack();
Rectangle tabBounds = tabbedPane.getBoundsAt(0);
Container glassPane = (Container) frame.getGlassPane();
glassPane.setVisible(true);
glassPane.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.weightx = 1.0;
gbc.weighty = 1.0;
gbc.fill = GridBagConstraints.NONE;
int margin = tabbedPane.getWidth() - (tabBounds.x + tabBounds.width);
gbc.insets = new Insets(0, 0, 0, margin);
gbc.anchor = GridBagConstraints.SOUTHEAST;
panel.setPreferredSize(new Dimension((int) tabBounds.getWidth() - margin,
panel.getPreferredSize().height));
glassPane.add(panel, gbc);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}