I am having trouble formatting the GUI for a program I am developing. I need to have four buttons with a JList above it. My JList keeps appearing besides all of my buttons instead of above them. Could anyone point me in the correct direction to solve my problem?
import java.awt.BorderLayout;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
public class Test extends JPanel {
private static final long serialVersionUID = 1L;
private JList jlist;
public static void main(String[] args) {
JFrame boxOptions = new JFrame("Calculator");
boxOptions.setSize(0,0);
boxOptions.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
boxOptions.setResizable(false);
boxOptions.setLayout(new BorderLayout());
boxOptions.add(new Test(), BorderLayout.CENTER);
boxOptions.pack();
boxOptions.setLocationRelativeTo(null);
boxOptions.setVisible(true);
}
public Test(){
setLayout(new GridLayout(1, 4, 5, 5));
add(new JButton("add"));
add(new JButton("Check In"));
add(new JButton("Check Out"));
add(new JButton("Delete"));
String[] Titles = {"one", "two", "three"};
jlist = new JList(Titles);
jlist.setVisibleRowCount(3);
add(new JScrollPane(jlist), BorderLayout.NORTH);
}
}
You're setting the layout of your Test JPanel class to GridLayout, and then trying to add a component to it using BorderLayout.NORTH specifier -- which is not kosher as that specifier only works for a BorderLayout and is meaningless for your GridLayout-using Test JPanel.
Solution: nest JPanels. Have an outer JPanel use a BorderLayout, and add the list's JScrollPane to this outer JPanel using the BorderLayout.NORTH specifier, and then create an inner JPanel that uses GridLayout, that holds your JButtons and add it to the main outer JPanel in the BorderLayout.CENTER position.
Most important though: read the Swing tutorials which you can find here, in particular the section on using the layout managers, since there is no need to guess at this stuff.
First of all , the BorderLayout Parameters use only when the layout is BorderLayout.
You can use GridBagLayout Instead. Sample code is below
setLayout(new GridBagLayout());
add(new JButton("add"), new GridBagConstraints(0, 1, 1, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 0, 0, 0), 0, 0));
add(new JButton("Check In"), new GridBagConstraints(1, 1, 1, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 0, 0, 0), 0, 0));
add(new JButton("Check Out"), new GridBagConstraints(2, 1, 1, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 0, 0, 0), 0, 0));
add(new JButton("Delete"), new GridBagConstraints(3, 1, 1, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 0, 0, 0), 0, 0));
String[] Titles = {"one", "two", "three"};
jlist = new JList(Titles);
jlist.setVisibleRowCount(3);
add(new JScrollPane(jlist), new GridBagConstraints(0, 0, 4, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 0, 0, 0), 0, 0));
Is this you expected ?
Related
public void createSpringLayout(SpringLayout spring, JLabel label, JScrollPane scrollPane, JPanel buttonPanel) {
spring.putConstraint(SpringLayout.NORTH, label, 10, SpringLayout.NORTH, this);
spring.putConstraint(SpringLayout.WEST, label, 10, SpringLayout.WEST, this);
spring.putConstraint(SpringLayout.NORTH, scrollPane, 10, SpringLayout.SOUTH, label);
spring.putConstraint(SpringLayout.WEST, scrollPane, 0, SpringLayout.WEST, label);
spring.putConstraint(SpringLayout.EAST, scrollPane, -10, SpringLayout.EAST, this);
spring.putConstraint(SpringLayout.NORTH, buttonPanel, Spring.constant(10, 30, 30), SpringLayout.SOUTH, scrollPane);
spring.putConstraint(SpringLayout.SOUTH, buttonPanel, -10, SpringLayout.SOUTH, this);
spring.putConstraint(SpringLayout.WEST, buttonPanel, 0, SpringLayout.WEST, label);
}
The two Jpanels with all the stuff on them are using the same superclass for better looks.
However as you can see if the contents of the scrollpane are to wide the scrollpane just uses extra space in the bottom to create a horizontal scrollbar.
Even if I tell the Springlayout that the spring between the scrollpane and the buttonPanel can be between 10 and 30.
I think that first the SpringLayoutManager is called to layout its components and then the ScrollPane comes along and notices that its displayed Components do not fit in the Viewport and creates a Scrollbar, which the SpringLayoutManager is unaware of.
I can't find any solution tha tell the ScrollPane beforehand to calculate its needed Size or for it to just dont use more Space than it has from the beginning.
Do not pass negative numbers to putConstraint.
From the documentation of putConstraint:
Links edge e1 of component c1 to edge e2 of component c2, with a fixed distance between the edges.
The pad value is not an absolute pixel offset, it is the amount of padding (the distance) between the component and the linked edge. It should always be positive.
The same javadoc also describes the pad parameter as:
pad - the fixed distance between dependent and anchor
SpringLayout is complex, which means it’s easy to make mistakes with it. You can easily accomplish the same layout with a BorderLayout:
setLayout(new BorderLayout());
add(label, BorderLayout.PAGE_START);
add(scrollPane, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.PAGE_END);
label.setBorder(BorderFactory.createEmptyBorder(0, 0, 10, 0));
buttonPanel.setBorder(BorderFactory.createEmptyBorder(10, 0, 0, 0));
this.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
I have a ScrollPane in a SplitPane and the ScrollPane contains a Gridbag layout panel.
I like to add horizontal filling Buttons to it.
Setting weightx and filling does not help at all.
I already tried it by using the dividers property listener, but nothing works.
Thanks for your answers!
Should be no problem:
// ScrollPane in a SplitPane
var scrollPane = new JScrollPane();
var splitPane = new JSplitPane();
splitPane.setLeftComponent(scrollPane);
splitPane.setRightComponent(new JLabel("dummy"));
// ScrollPane contains a Gridbag layout panel
var gridBagLayout = new GridBagLayout();
var panel = new JPanel(gridBagLayout);
scrollPane.setViewportView(panel);
// add horizontal filling Buttons
var gbc = new GridBagConstraints(
0, RELATIVE, 1, 1, 1.0, 0.0,
CENTER, HORIZONTAL, new Insets(2, 2, 2, 2), 0, 0);
panel.add(new JButton("first"), gbc);
panel.add(new JButton("second"), gbc);
JOptionPane.showMessageDialog(null, splitPane);
I have the following class
public class Demo {
private JFrame mainFrame;
static public Color BGCOLOUR1 = new Color(240, 240, 240);
public Demo() {
mainFrame = new JFrame("Demo");
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainFrame.setLayout(new BorderLayout());
mainFrame.setSize(900, 800);
JPanel centralPanel = new JPanel();
centralPanel.setOpaque(true);
centralPanel.setBackground(BGCOLOUR1);
centralPanel.setLayout(new GridBagLayout());
centralPanel.setBorder(BorderFactory.createCompoundBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20),
BorderFactory.createTitledBorder("Panel")));
JPanel insidePanel = new JPanel();
insidePanel.setOpaque(true);
insidePanel.setBackground(BGCOLOUR1);
insidePanel.setLayout(new BorderLayout());
insidePanel.setBorder(BorderFactory.createCompoundBorder(BorderFactory.createTitledBorder("Inside panel"),
BorderFactory.createEmptyBorder(10, 10, 10, 10)));
JTextArea insidePanelText = new JTextArea(6, 50);
insidePanelText.setLineWrap(true);
insidePanel.add(insidePanelText);
centralPanel.add(insidePanel, new GridBagConstraints(0, 0, 1, 1, 1, 0, GridBagConstraints.NORTH,
GridBagConstraints.HORIZONTAL, new Insets(10, 10, 10, 10), 0, 0));
JScrollPane scrollPane = new JScrollPane(centralPanel);
mainFrame.add(scrollPane);
}
Why is the inside panel positioned in the centre of the centralPanel (vertically) when I set the GridBagConstraints anchor to NORTH? I would like it positioned at the top.
Also, if I add the centralPanel in a JScrollPane before adding it to the mainFrame as per the example I can resize the application larger just fine, but as soon as I resize it smaller (even though it is still larger than I originally started it) a scroll bar appears. How can I prevent that from happening?
Edit: To illustrate the scrolling problem (I packed the frame when I took these screens):
When I start the application it has no scrollbars
I resize the window larger, and then smaller again. As soon as I make it smaller, the scrollbar appears.
As far as GridBagLayout is concerned, based on the properties you've supplied, it is been laid out to the NORTH of the cell.
GridBagLayout works mostly to the preferred size of the components and calculates the positions of each component around the center of the parent container.
If, instead of:
new GridBagConstraints(0, 0, 1, 1, 1, 0, GridBagConstraints.NORTH,
GridBagConstraints.HORIZONTAL, new Insets(10, 10, 10, 10), 0, 0)
I use something like:
new GridBagConstraints(0, 0, 1, 1, 1, 1, GridBagConstraints.NORTH,
GridBagConstraints.HORIZONTAL, new Insets(10, 10, 10, 10), 0, 0)
it will produce the desired result.
Basically, by using gridy and setting it to 1, we're asking GridBagLayout to give all the remaining vertical space to this cell, but because we're not filling the cell, the contents is pushed to the NORTH of the cell
Also, if I add the centralPanel in a JScrollPane before adding it to the mainFrame as per the example I can resize the application larger just fine, but as soon as I resize it smaller (even though it is still larger than I originally started it) a scroll bar appears. How can I prevent that from happening?
I couldn't really replicate this particular problem, I could use either pack or setSize and resized the window smaller to its "packed" size and the scroll bars would appear, but once I resized the window beyond the "packed" size the scroll bars would disappear
I am working on a simple little swing application for a relative, but I'm having trouble implementing animations on it...
Here is a description of my layout:
I have a main window (created by instantiating, packing, and displaying a JFrame).
I have told the content panel of the main window to use GridBagLayout as its layout.
My grid is 2 grids wide, and 3 grids tall. In the first column I have three JButtons (A, B, and C), each taking up one row of vertical grid space, and one column of horizontal grid space. In the second column, I have another JPanel, which is one column wide, and three rows tall.
This second JPanel is also set to use GridBagLayout as its layout. In this case, there are two columns, and one row. The left column has a one collumn wide, one row tall JPanel with Button 1 inside of it. The right column consists of just a single JButton (Button 2), which is also one column wide, and one row tall.
Here is a screenshot of what I just described:
Now that you understand what the layout is, let me explain what I've been trying to do:
I've been trying to use the Universal Tween Engine to resize the Jpanel which contains Button 1. However, in my attempts, I get this as a result:
As you can probably see, the JPanel containing Button 1 has successfully resized! However, Button 2's size and position have not change at all, and, in fact, button 2 is getting cut off by the JPanel containing Button 1!
This is a problem, as I expected resizing the JPanel containing Button 1 to simultaneously change the cell sizes of its containing GridBagLayout. I was sorely mistaken on this matter, it seems.
So that brings me to my question... What do I need to do in order to "Update" my GridBagLayout so that it resizes its grids to accommodate the increase in size from the Jpanel containing Button 1? I have tried calling GridBagLayout.invalidatelayout() on my GridBaglayout, and I have also tried calling JFrame.getContentPane().invalidate() on my main window. Neither seemed to have had any effect.
Here is the compilable source code of my project:
ImageManager.java:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import aurelienribon.tweenaccessors.swing.*;
import aurelienribon.utils.swing.*;
import aurelienribon.tweenengine.*;
import aurelienribon.tweenengine.equations.*;
public class ImageManager
{
/**
* #param args
*/
public static JFrame mainwindow;
public static TweenManager tweenManager;
public static void main(String[] args)
{
javax.swing.SwingUtilities.invokeLater(new Runnable() //For thread safety!
{
public void run()
{
InitGUI();
InitTween();
}
});
}
private static void InitTween()
{
((Window)mainwindow).addWindowListener(new WindowAdapter() {
#Override public void windowOpened(WindowEvent e)
{
new DrawingCanvas()
{
#Override protected void update(int elapsedMillis)
{
tweenManager.update(elapsedMillis);
}
}.start();
}
});
}
private static void InitGUI()
{
//Init the window and layout systems
mainwindow = new JFrame("Imaffect");
Container pane = mainwindow.getContentPane();
pane.setLayout(new GridBagLayout());
//Begin creating the UI!
pane.add(new JButton("Button A"), new GridBagConstraints(0, 0, 1, 1, 0, 1, GridBagConstraints.PAGE_START, GridBagConstraints.VERTICAL, new Insets(0,0,0,0), 100, 0));
pane.add(new JButton("Button B"), new GridBagConstraints(0, 1, 1, 1, 0, 0, GridBagConstraints.PAGE_START, GridBagConstraints.VERTICAL, new Insets(0,0,0,0), 100, 100));
pane.add(new JButton("Button C"), new GridBagConstraints(0, 2, 1, 1, 0, 0, GridBagConstraints.PAGE_START, GridBagConstraints.VERTICAL, new Insets(0,0,0,0), 100, 20));
pane.add(InitPreviewGUI(), new GridBagConstraints(1, 0, 1, 3, 1, 1, GridBagConstraints.PAGE_START, GridBagConstraints.BOTH, new Insets(0,0,0,0), 0, 0));
//Finalize the window
mainwindow.pack();
mainwindow.setVisible(true);
}
private static JPanel InitPreviewGUI()
{
JPanel panel = new JPanel(new GridBagLayout());
panel.add(InitSettingsGUI(), new GridBagConstraints(0, 0, 1, 1, 0, 1, GridBagConstraints.PAGE_START, GridBagConstraints.BOTH, new Insets(0,0,0,0), 0, 0));
panel.add(new JButton("Button 2"), new GridBagConstraints(1, 0, 1, 1, 1, 1, GridBagConstraints.PAGE_START, GridBagConstraints.BOTH, new Insets(0,0,0,0), 0, 0));
return panel;
}
private static JPanel InitSettingsGUI()
{
JPanel panel = new JPanel();
SetupSettingsTweens(panel);
SetupSettingsContent(panel);
return panel;
}
private static void SetupSettingsTweens(JPanel panel)
{
Tween.registerAccessor(Component.class, new ComponentAccessor());
tweenManager = new TweenManager();
Tween.to(panel, ComponentAccessor.WIDTH, 1000)
.target(200)
.ease(Cubic.INOUT)
.repeatYoyo(-1, 200)
.delay(500)
.start(tweenManager);
}
private static void SetupSettingsContent(JPanel panel)
{
panel.add(new JButton("Button 1"));
}
}
If you want to compile the code yourself, you will need the following three resources:
Universal Tween Engine library jar
DrawingCanvas.java (package aurelienribon.utils.swing)
ComponentAccessor.java (package aurelienribon.tweenaccessors.swing)
If you would like to experience my problem first hand, without complicated project setup, you may download the Eclipse Juno project, or the runnable jar file:
Imaffect Eclipse Juno Project
Imaffect Runnable Jar File
If you would prefer to stay away from downloads, here is a list of what's going on:
Set up GUI structure
Set up requirements for tween (nothing special)
Set up a thread that uses SwingUtilities.invokeAndWait to call a function called update()
Whenever update() is called, it uses Container.setSize() to animate size change on the JPanel that contains Button 1.
Any help with this problem is greatly appreciated! Thankyou :)
P.S. If there is a duplicate of this question, I am very sorry. I googled around quite a bit, but I was unable to find anything even related to my problem.
I would say in your update() method you should change preferred size of Button1 and call
container.revalidate();
container.repaint();
Changing the preferred size and revalidate() updates layout and repaint() reflects the changes.
Alternatively you can call setSize() for Button1 increasing width and in the same time decrease width of Button2 and again call repaint() (without revalidate() because revalidation would restore original layout).
I have components laid out in a GridBagLayout. I want a 1px black line between all the components, as well as around the JPanel itself.
Currently, I am using a MatteBorder to do this. The parent component has a 1px MatteBorder on the top and left edges. Each child component has a 1px MatteBorder on the right and bottom edges. The horizontal and vertical gaps are zero on the GridBagLayout.
This mostly works, except I'm getting occasional gaps where the child borders meet the parent border.
I suspect this is due to a rounding/floating point inaccuracy in the distribution of extra space to the child components.
Is there a better way to achieve this look?
Attached is a simpler example:
public class SSBGuiTest extends JDialog {
public SSBGuiTest(Frame owner) {
super(owner);
initComponents();
}
public SSBGuiTest(Dialog owner) {
super(owner);
initComponents();
}
private void initComponents() {
// JFormDesigner - Component initialization - DO NOT MODIFY //GEN-BEGIN:initComponents
wrapperPanel = new JPanel();
panelWithTopLeftMatteBorder = new JPanel();
panel1 = new JPanel();
label1 = new JLabel();
panel2 = new JPanel();
label2 = new JLabel();
panel3 = new JPanel();
label3 = new JLabel();
//======== this ========
Container contentPane = getContentPane();
contentPane.setLayout(new BorderLayout());
//======== wrapperPanel ========
{
wrapperPanel.setBorder(new EmptyBorder(15, 15, 15, 15));
wrapperPanel.setLayout(new BorderLayout());
//======== panelWithTopLeftMatteBorder ========
{
panelWithTopLeftMatteBorder.setBorder(new MatteBorder(1, 1, 0, 0, Color.black));
panelWithTopLeftMatteBorder.setLayout(new GridBagLayout());
((GridBagLayout)panelWithTopLeftMatteBorder.getLayout()).columnWidths = new int[] {0, 0};
((GridBagLayout)panelWithTopLeftMatteBorder.getLayout()).rowHeights = new int[] {0, 0, 0, 0};
((GridBagLayout)panelWithTopLeftMatteBorder.getLayout()).columnWeights = new double[] {1.0, 1.0E-4};
((GridBagLayout)panelWithTopLeftMatteBorder.getLayout()).rowWeights = new double[] {1.0, 1.0, 1.0, 1.0E-4};
//======== panel1 ========
{
panel1.setBorder(new MatteBorder(0, 0, 1, 1, Color.black));
panel1.setLayout(new BorderLayout());
//---- label1 ----
label1.setHorizontalAlignment(SwingConstants.CENTER);
label1.setText("label1");
panel1.add(label1, BorderLayout.CENTER);
}
panelWithTopLeftMatteBorder.add(panel1, new GridBagConstraints(0, 0, 1, 1, 0.0, 0.0,
GridBagConstraints.CENTER, GridBagConstraints.BOTH,
new Insets(0, 0, 0, 0), 0, 0));
//======== panel2 ========
{
panel2.setBorder(new MatteBorder(0, 0, 1, 1, Color.black));
panel2.setLayout(new BorderLayout());
//---- label2 ----
label2.setHorizontalAlignment(SwingConstants.CENTER);
label2.setText("label2");
panel2.add(label2, BorderLayout.CENTER);
}
panelWithTopLeftMatteBorder.add(panel2, new GridBagConstraints(0, 1, 1, 1, 0.0, 0.0,
GridBagConstraints.CENTER, GridBagConstraints.BOTH,
new Insets(0, 0, 0, 0), 0, 0));
//======== panel3 ========
{
panel3.setBorder(new MatteBorder(0, 0, 1, 1, Color.black));
panel3.setLayout(new BorderLayout());
//---- label3 ----
label3.setHorizontalAlignment(SwingConstants.CENTER);
label3.setText("label3");
panel3.add(label3, BorderLayout.CENTER);
}
panelWithTopLeftMatteBorder.add(panel3, new GridBagConstraints(0, 2, 1, 1, 0.0, 0.0,
GridBagConstraints.CENTER, GridBagConstraints.BOTH,
new Insets(0, 0, 0, 0), 0, 0));
}
wrapperPanel.add(panelWithTopLeftMatteBorder, BorderLayout.CENTER);
}
contentPane.add(wrapperPanel, BorderLayout.CENTER);
pack();
setLocationRelativeTo(getOwner());
// JFormDesigner - End of component initialization //GEN-END:initComponents
}
// JFormDesigner - Variables declaration - DO NOT MODIFY //GEN-BEGIN:variables
private JPanel wrapperPanel;
private JPanel panelWithTopLeftMatteBorder;
private JPanel panel1;
private JLabel label1;
private JPanel panel2;
private JLabel label2;
private JPanel panel3;
private JLabel label3;
// JFormDesigner - End of variables declaration //GEN-END:variables
}
Which looks like this:
I think I'd use BorderFactory.createLineBorder(color, thickness) rather than ...matteBorder, since LineBorder seems to be a bit closer to what you're looking to do. As a convenience, you could also use LineBorder.createBlackLineBorder().
If the outsides of some components aren't quite hitting the insides of their containers, check that the containers (i.e. outer components) don't have non-zero insets set!
An alternate solution might be to let your background container have a black background and 1 pixel insets, and place non-bordered components on it with 1 pixel gaps between them. That should result in very precise black lines everywhere you don't have a component on top, and also eliminates the problem of multiple borders meeting up and resulting in a double-width border.
Finally, it looks to me like you're using components to draw tables. Do you need these components to have behavior of some sort, or would it be fine to really just put tables on your components? You could do this pretty conveniently using e.g. JLabels JTextPanels and setting their text properties to HTML for whatever you'd like to display. Java incorporates a fairly sophisticated HTML layout engine which even handles a goodly subset of CSS, either inline or even from a href'd file.