JFrame Buttons and GridBagConstraints - java

Why are my constraints for my buttons not working? I looked at the Java Docs and am doing the same thing the tutorials are doing, but for me the buttons stay the same regardless of what gridx, y, width, or fill I use. Any ideas? Here's my code:
class MyWindow
{
public static void main(String [] arg)
{
MyJFrame f = new MyJFrame("My GUI 2015");
f.setVisible(true);
f.setSize(10, 20);
f.add(f.p);
}
}
and
public class MyJFrame extends JFrame {
public JPanel p;
JButton close = new JButton("close");
JButton drawing = new JButton("drawing");
JButton image = new JButton("image");
JButton browser = new JButton("browser");
public MyJFrame(String title) {
super(title);
p = new JPanel();
buildButtons();
}
void buildButtons() {
GridBagConstraints c = new GridBagConstraints();
c.insets = new Insets(0,40,0,150);
c.gridx = 0;
c.gridy = 0;
p.add(drawing, c);
c.gridx = 2;
c.gridy = 0;
p.add(close, c);
c.insets = new Insets(50,225,50,150);
c.gridx = 0;
c.gridy = 1;
p.add(image, c);
c.insets = new Insets(0,125,0,125);
c.gridx = 0;
c.gridy = 100;
c.gridwidth = 3;
c.fill = GridBagConstraints.HORIZONTAL;
p.add(browser, c);
}
}

The LayoutManager for the container is not specified in your current code (the default for a JPanel is FlowLayout). If you wish to use a GridBagLayout on the container, you must explicitly specify the LayoutManager:
p = new JPanel(new GridBagLayout());
//or
p.setLayout(new GridBagLayout());

Related

how to put components in the center in a CardLayout panel

I have a frame that has couple of panels and they change by CardLayout.
Inside each panel i will have different components. To design the GUI of the panel I used GridBagLayout. But the problem is any component or Layout I use for these paneles, they all stay at the top of the page. So basically the panel size of the CardLayout is some small amount of the frame. I want to make the sub panel size as large as the main CardLayout size.
Code for main CardLayout:
public class MainPanel extends JPanel {
private CardLayout cl = new CardLayout();
private JPanel panelHolder = new JPanel(cl);
public MainPanel() {
NewSession session = new NewSession(this);
ChooseSource chooseSource = new ChooseSource(this);
panelHolder.add(session, "1");
panelHolder.add(chooseSource, "2");
cl.show(panelHolder, "dan");
add(panelHolder);
}
public void showPanel(String panelIdentifier){
cl.show(panelHolder, panelIdentifier);
}
}
A sub panel:
public class ChooseSource extends JPanel {
MainPanel ob2;
JButton btn;
JLabel label;
JTextField field;
public ChooseSource(MainPanel mainPanel){
this.ob2 = mainPanel;
btn = new JButton("Browse");
label = new JLabel("Folder ");
field = new JTextField();
btn.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent e){
ob2.showPanel("1");
}
});
GridBagLayout layout = new GridBagLayout();
setLayout(layout);
GridBagConstraints c = new GridBagConstraints();
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 0;
c.ipady = 20;
c.gridheight = 2;
add(btn, c);
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 1;
c.gridy = 0;
c.ipady = 10;
c.gridheight = 1;
c.insets = new Insets(0,10,0,0);
add(label, c);
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 1;
c.gridy = 1;
c.ipady = 0;
c.gridheight = 1;
c.insets = new Insets(0,10,0,0);
add(field, c);
}
}
The left image shows how it is not, and right one is the one I am trying to make. basically I want to have access to all the available space of the panel.
Any idea?
Change the layout manager of MainPanel to something like BorderLayout or GridBagLayout

JFrame buttons act weird when declaring it to a static variable

So, I am having some really weird stuff going on here.
So, my entire class is this:
public class Test extends JFrame {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
new Test();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public static void addComponentsToPane(Container pane) {
JButton button;
pane.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
button = new JButton("Button 1");
if (shouldWeightX) {
c.weightx = 0.5;
}
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 0;
pane.add(button, c);
button = new JButton("Button 2");
c.fill = GridBagConstraints.HORIZONTAL;
c.weightx = 0.5;
c.gridx = 1;
c.gridy = 0;
pane.add(button, c);
button = new JButton("Button 3");
c.fill = GridBagConstraints.HORIZONTAL;
c.weightx = 0.5;
c.gridx = 2;
c.gridy = 0;
pane.add(button, c);
button = new JButton("Long-Named Button 4");
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 50;
c.weightx = 0.0;
c.gridwidth = 3;
c.gridx = 0;
c.gridy = 1;
pane.add(button, c);
button = new JButton("5");
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 20;
c.weighty = 1.0;
c.anchor = GridBagConstraints.PAGE_END;
c.insets = new Insets(10,0,0,0);
c.gridx = 0;
c.gridwidth = 3;
c.gridy = 3;
pane.add(button, c);
}
private JFrame createAndShowGUI(JFrame frame) {
frame = new JFrame("GridBagLayoutDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
addComponentsToPane(frame.getContentPane());
frame.pack();
frame.setVisible(true);
return frame;
}
JFrame frame = null;
public Test() {
createAndShowGUI(frame);
addComponentsToPane(frame.getContentPane());
}
}
So anyway, I am going to focus on this bit:
JFrame frame = null;
public Test() {
createAndShowGUI(frame);
addComponentsToPane(frame.getContentPane());
}
Which, produces this result (which works perfectly fine).
However, when I use this code:
JFrame frame = null;
public Test() {
frame = createAndShowGUI(frame);
addComponentsToPane(frame.getContentPane());
}
Which results in buttons 4 and 5 somehow duplicating themselves with a set size at the top of the screen. Also, buttons 4 and 5 appear to have different sizes.
Like this:
(And when I make the window smaller)
What is causing this? All I am doing is setting a variable from null or a JFrame, which should do nothing.
The first method throws a NullPointerException at the addComponentsToPane method because the frame attribute is never initialized and the second method adds the buttons twice to the frame. I have rewritten the code below and it works fine. You should also have a look at variable shadowing , because your frame attribute gets shadowed by the frame local variable in the addComponentsToPane method whick is rarely a good idea.
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
new Test();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public static void addComponentsToPane(Container pane) {
JButton button;
pane.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
button = new JButton("Button 1");
if (true) {
c.weightx = 0.5;
}
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 0;
pane.add(button, c);
button = new JButton("Button 2");
c.fill = GridBagConstraints.HORIZONTAL;
c.weightx = 0.5;
c.gridx = 1;
c.gridy = 0;
pane.add(button, c);
button = new JButton("Button 3");
c.fill = GridBagConstraints.HORIZONTAL;
c.weightx = 0.5;
c.gridx = 2;
c.gridy = 0;
pane.add(button, c);
button = new JButton("Long-Named Button 4");
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 50;
c.weightx = 0.0;
c.gridwidth = 3;
c.gridx = 0;
c.gridy = 1;
pane.add(button, c);
button = new JButton("5");
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 20;
c.weighty = 1.0;
c.anchor = GridBagConstraints.PAGE_END;
c.insets = new Insets(10, 0, 0, 0);
c.gridx = 0;
c.gridwidth = 3;
c.gridy = 3;
pane.add(button, c);
}
private void createAndShowGUI() {
frame = new JFrame("GridBagLayoutDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
JFrame frame = null;
public Test() {
createAndShowGUI();
addComponentsToPane(frame.getContentPane());
frame.pack();
frame.setVisible(true);
}

Vertical filling of GridBagLayout in Java does not work

I am having troubles getting the layout right.
I have a Class which extends JFrame and has a JPanel which has a the GridBagLayout as layout manager. I want 4 buttons which should be layout in this way
Somehow the vertical filling does not work.
I tried various ways but can't figure out how to make this work.
Sorry if this is a noob question, but tried it for more than an hour without any change :/
public class ButtonPanel extends JFrame {
private static final long serialVersionUID = 1L;
public ButtonPanel() {
this.setSize(800, 600);
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setVisible(true);
frame();
}
JButton objectsBtn = new JButton("Objekte"); //TODO Strings einfügen
JButton tenantBtn = new JButton("Mieter"); //TODO Strings einfügen
JButton ownerBtn = new JButton("Eigentümer"); //TODO Strings einfügen
JButton optionsBtn = new JButton("Einstellungen"); //TODO Strings einfügen
JPanel panel = new JPanel();
public void frame(){
panel.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
c.insets = new Insets(5, 5, 5, 5);
c.fill = GridBagConstraints.BOTH;
c.gridwidth = GridBagConstraints.RELATIVE;
c.gridheight = GridBagConstraints.RELATIVE;
//Elemente
c.weightx = 1.0;
c.weighty = 1.0;
c.gridx = 0;
c.gridy = 0;
panel.add(objectsBtn, c);
c.weightx = 1.0;
c.weighty = 1.0;
c.gridx = 1;
c.gridy = 0;
panel.add(optionsBtn, c);
c.weightx = 1.0;
c.weighty = 1.0;
c.gridx = 0;
c.gridy = 1;
panel.add(ownerBtn, c);
c.weightx = 1.0;
c.weighty = 1.0;
c.gridx = 1;
c.gridy = 1;
panel.add(tenantBtn, c);
this.add(panel);
objectsBtn.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
new Object();
}
});
ownerBtn.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//TODO Eigentümer erstellen
}
});
}
}
greets
THE-E
EDIT: Found the bug
I used Seaglass as Look and Feel in the main-method
//Set Theme
try {
UIManager.setLookAndFeel("com.seaglasslookandfeel.SeaGlassLookAndFeel");
} catch (Exception e) {
e.printStackTrace();
}
It works fine with the default Look and Feel Theme.
I have added the answer in the first post. It was a bug caused by the LookAndFeel skin. :/
greets
THE-E

Java Swing - realising a layout with LayeredPane

I have a question regarding making a specific Layout, first I'll show examples then I will add some extra clarification.
Layout when Friends and Messages are closed:
Layout when Friends and Messages are opened:
I intend to make this layout with Java Swing.
My intention is to firstly have the Frame divided in three areas, the top menu row, the main panel and the bottom menu row.
I was thinking of using a BorderLayout for this part.
Then the Friends and Messages buttons should be toggle button's, and on toggle they should show an overlay on top of the mainpanel (or whatever is there), containing a friend list and a message area. I realised I need to use a LayeredPane somehow for this.
Another important part is that the Layout should be viewable in any size, that is the user may resize the application and it will be used on a various amount of resolutions, so I don't really want anything with a fixed width and height.
But I am really lost as how to combine this, so therefore I ask your help.
Hopefully I have explained enough about the situation.
Regards.
this could be about overlay, because JPanel can contains other JComponents
use JLayer (Java7) based on JXLayer(Java6),
use GlassPane with JComponents layed to rellative to....
easiest could be to use JDialog(undecorated) layed to Point (setLocation(int, int)), setVisible() must be wrapped into invokeLater
I will use gridBagLayout.
Here is small example including button which hide your yellow panels:
package Core;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class GridBagLayoutDemo {
public static void addComponentsToPane(Container pane) {
pane.setLayout(new GridBagLayout());
add1row(pane);
addmainRow(pane);
addLastRow(pane);
}
private static void addLastRow(Container pane) {
GridBagConstraints c = new GridBagConstraints();
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 3;
c.anchor = GridBagConstraints.PAGE_END;
JPanel bottonPanel = new JPanel();
bottonPanel.setBackground(Color.BLUE);
bottonPanel.setLayout(new GridBagLayout());
pane.add(bottonPanel, c);
JPanel messagePanel = new JPanel();
messagePanel.setBackground(Color.GRAY);
messagePanel.add(new JLabel("MESSAGES"));
c.fill = GridBagConstraints.VERTICAL;
c.anchor = GridBagConstraints.LINE_END;
c.gridx = 0;
c.gridy = 0;
c.weightx = 1;
bottonPanel.add(messagePanel, c);
}
private static void addmainRow(Container pane) {
GridBagConstraints c = new GridBagConstraints();
c.fill = GridBagConstraints.BOTH;
c.gridx = 0;
c.gridy = 1;
c.weightx = 1;
c.weighty = 1;
c.anchor = GridBagConstraints.CENTER;
JPanel mainManel = new JPanel();
mainManel.setBackground(Color.GREEN);
mainManel.setLayout(new GridBagLayout());
pane.add(mainManel, c);
final JPanel friendListPanel = new JPanel();
friendListPanel.setBackground(Color.YELLOW);
friendListPanel.add(new JLabel("FRIEND LIST"));
c.fill = GridBagConstraints.NONE;
c.gridx = 0;
c.gridy = 0;
c.weightx = 1;
c.weighty = 1;
c.anchor = GridBagConstraints.FIRST_LINE_END;
mainManel.add(friendListPanel, c);
c.fill = GridBagConstraints.NONE;
c.gridx = 0;
c.gridy = 1;
c.weightx = 0;
c.weighty = 0;
c.anchor = GridBagConstraints.CENTER;
JButton button = new JButton("On/Off");
mainManel.add(button, c);
final JPanel messageAreaPanel = new JPanel();
messageAreaPanel.setBackground(Color.YELLOW);
messageAreaPanel.add(new JLabel("MESSAGE PANEL"));
c.fill = GridBagConstraints.NONE;
c.gridx = 0;
c.gridy = 2;
c.weightx = 1;
c.weighty = 1;
c.anchor = GridBagConstraints.LAST_LINE_END;
mainManel.add(messageAreaPanel, c);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
friendListPanel.setVisible(!friendListPanel.isVisible());
messageAreaPanel.setVisible(!messageAreaPanel.isVisible());
}
});
}
private static void add1row(Container pane) {
GridBagConstraints c = new GridBagConstraints();
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 0;
c.anchor = GridBagConstraints.PAGE_START;
Panel headerPanel = new Panel();
headerPanel.setLayout(new GridBagLayout());
headerPanel.setBackground(Color.BLUE);
pane.add(headerPanel, c);
JPanel quitPanel = new JPanel();
quitPanel.setBackground(Color.GRAY);
quitPanel.add(new JLabel("QUIT"));
c.fill = GridBagConstraints.VERTICAL;
c.anchor = GridBagConstraints.LINE_START;
c.gridx = 0;
c.gridy = 0;
c.weightx = 1;
headerPanel.add(quitPanel, c);
JPanel friendsPanel = new JPanel();
friendsPanel.setBackground(Color.GRAY);
friendsPanel.add(new JLabel("FRIENDS"));
c.fill = GridBagConstraints.VERTICAL;
c.anchor = GridBagConstraints.LINE_END;
c.gridx = 1;
c.gridy = 0;
headerPanel.add(friendsPanel, c);
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("GridBagLayoutDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
addComponentsToPane(frame);
// uncoment to use full screen
// frame.setExtendedState(frame.getExtendedState() | JFrame.MAXIMIZED_BOTH);
frame.setSize(new Dimension(400, 400));
frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}

How to align left or right inside GridBagLayout cell?

I see that GridBagLayout positions it's children with center alignment within cells. How to align left or right?
UPDATE
Constructing code (I know I could reuse c)
// button panel
JPanel button_panel = new JPanel();
button_panel.add(ok_button);
button_panel.add(cancel_button);
// placing controls to dialog
GridBagConstraints c;
GridBagLayout layout = new GridBagLayout();
setLayout(layout);
c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 0;
add(inputSource_label, c);
c = new GridBagConstraints();
c.gridx = 1;
c.gridy = 0;
add(inputSource_combo, c);
c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 1;
add(output_label, c);
c = new GridBagConstraints();
c.gridx = 1;
c.gridy = 1;
add(output_combo, c);
c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 2;
c.gridwidth = 2;
add(button_panel, c);
When using GridBagLayout for a tabular display of JLabel : JTextField, I like to have a method that makes my GridBagConstraints for me based on the x, y position. For example something like so:
private GridBagConstraints createGbc(int x, int y) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.gridwidth = 1;
gbc.gridheight = 1;
gbc.anchor = (x == 0) ? GridBagConstraints.WEST : GridBagConstraints.EAST;
gbc.fill = (x == 0) ? GridBagConstraints.BOTH
: GridBagConstraints.HORIZONTAL;
gbc.insets = (x == 0) ? WEST_INSETS : EAST_INSETS;
gbc.weightx = (x == 0) ? 0.1 : 1.0;
gbc.weighty = 1.0;
return gbc;
}
The following code makes a GUI that looks like this:
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.util.HashMap;
import java.util.Map;
import javax.swing.*;
public class GridBagEg {
private static void createAndShowGui() {
PlayerEditorPanel playerEditorPane = new PlayerEditorPanel();
int result = JOptionPane.showConfirmDialog(null, playerEditorPane,
"Edit Player", JOptionPane.OK_CANCEL_OPTION,
JOptionPane.PLAIN_MESSAGE);
if (result == JOptionPane.OK_OPTION) {
// TODO: do something with info
for (PlayerEditorPanel.FieldTitle fieldTitle :
PlayerEditorPanel.FieldTitle.values()) {
System.out.printf("%10s: %s%n", fieldTitle.getTitle(),
playerEditorPane.getFieldText(fieldTitle));
}
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
#SuppressWarnings("serial")
class PlayerEditorPanel extends JPanel {
enum FieldTitle {
NAME("Name"), SPEED("Speed"), STRENGTH("Strength");
private String title;
private FieldTitle(String title) {
this.title = title;
}
public String getTitle() {
return title;
}
};
private static final Insets WEST_INSETS = new Insets(5, 0, 5, 5);
private static final Insets EAST_INSETS = new Insets(5, 5, 5, 0);
private Map<FieldTitle, JTextField> fieldMap = new HashMap<FieldTitle, JTextField>();
public PlayerEditorPanel() {
setLayout(new GridBagLayout());
setBorder(BorderFactory.createCompoundBorder(
BorderFactory.createTitledBorder("Player Editor"),
BorderFactory.createEmptyBorder(5, 5, 5, 5)));
GridBagConstraints gbc;
for (int i = 0; i < FieldTitle.values().length; i++) {
FieldTitle fieldTitle = FieldTitle.values()[i];
gbc = createGbc(0, i);
add(new JLabel(fieldTitle.getTitle() + ":", JLabel.LEFT), gbc);
gbc = createGbc(1, i);
JTextField textField = new JTextField(10);
add(textField, gbc);
fieldMap.put(fieldTitle, textField);
}
}
private GridBagConstraints createGbc(int x, int y) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.gridwidth = 1;
gbc.gridheight = 1;
gbc.anchor = (x == 0) ? GridBagConstraints.WEST : GridBagConstraints.EAST;
gbc.fill = (x == 0) ? GridBagConstraints.BOTH
: GridBagConstraints.HORIZONTAL;
gbc.insets = (x == 0) ? WEST_INSETS : EAST_INSETS;
gbc.weightx = (x == 0) ? 0.1 : 1.0;
gbc.weighty = 1.0;
return gbc;
}
public String getFieldText(FieldTitle fieldTitle) {
return fieldMap.get(fieldTitle).getText();
}
}
In this example, I display the JPanel in a JOptionPane, but it could just as easily be displayed in a JFrame or JApplet or JDialog or ...
For example
public class DimsPanel extends JPanel
{
public static void main(String[] args){
JFrame main = new JFrame("Dims");
JPanel myPanel = new DimsPanel();
main.setContentPane(myPanel);
main.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
main.setSize(400, 400);
main.setLocationRelativeTo(null);
main.setVisible(true);
}
JButton ok_button = new JButton("OK"), cancel_button = new JButton("Cancel");
JLabel inputSource_label = new JLabel("Input source:"),
output_label = new JLabel("Output:");
JComboBox inputSource_combo = new JComboBox(new String[]{"A", "B", "C"}),
output_combo = new JComboBox(new String[]{"A", "B", "C"});
public DimsPanel(){
super(new BorderLayout());
Box main = new Box(BoxLayout.Y_AXIS);
Dimension labelsWidth = new Dimension(100, 0);
JPanel inputPanel = new JPanel(new BorderLayout());
inputSource_label.setPreferredSize(labelsWidth);
inputPanel.add(inputSource_label, BorderLayout.WEST);
inputPanel.add(inputSource_combo);
JPanel outputPanel = new JPanel(new BorderLayout());
output_label.setPreferredSize(labelsWidth);
outputPanel.add(output_label, BorderLayout.WEST);
outputPanel.add(output_combo);
// button panel
JPanel button_panel = new JPanel();
button_panel.add(ok_button);
button_panel.add(cancel_button);
main.add(inputPanel);
main.add(outputPanel);
add(main, BorderLayout.NORTH);
add(button_panel);
}
}
You can run and see it. Resizing works like a charm and the layout code has only 18 lines.
The only disadvantage is that you need to specify the width of the labels by hand. If you really don't want to see setPreferredSize() in the code, then be my guest and go with GridBag. But I personally like this code more.

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