Java Swing - Resize JPanel on componentResized() event - java

I'm trying to resize a JPanel to 100% width within a JFrame when window is resized. But the JPanel never gets resized...
I'm using IntelliJ
Here is my code:
public static void createAndShowGUI() {
frame = new JFrame("MyApplication");
frame.setLayout(new GridBagLayout());
menuPanel = new MenuPanel();
contentPanel = new ContentPanel();
MainFrame mainFrame = new MainFrame();
vimInitialiser = new VimInitialiser();
frame.addWindowListener(mainFrame);
frame.addComponentListener(mainFrame);
JComponent newContentPane = mainFrame;
newContentPane.setOpaque(true);
frame.setContentPane(newContentPane);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setMinimumSize(new Dimension(1200, 500));
frame.pack();
frame.setVisible(true);
frame.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
frame.add(menuPanel.getMenuPanel());
frame.add(contentPanel.getContentPanel());
}
Here is my JPanel classes:
public class ContentPanel extends JPanel{
public JPanel getContentPanel(){
JPanel contentPanel = new JPanel(true);
JLabel label = new JLabel("ContentPanel");
Border border = BorderFactory.createLineBorder(Color.black);
contentPanel.setPreferredSize(new Dimension(940, 480));
contentPanel.setBorder(border);
contentPanel.add(label);
return contentPanel;
}
}
public class MenuPanel extends JPanel{
public JPanel getMenuPanel(){
JPanel menuPanel = new JPanel(true);
JLabel label = new JLabel("MenuPanel");
Border border = BorderFactory.createLineBorder(Color.black);
menuPanel.setPreferredSize(new Dimension(200, 480));
menuPanel.setBorder(border);
menuPanel.add(label);
return menuPanel;
}
}
Pleas help me whit this problem.

Try using a BorderLayout.
frame.setLayout(new BorderLayout());
And then add the panes like this:
frame.add(menuPanel.getMenuPanel(), BorderLayout.NORTH);
frame.add(contentPanel.getContentPanel(), BorderLayout.CENTER);

I believe the mistake is that you are not setting the 'fill' and 'weight' for the gridbagconstraints. I think this will solve the problem.
GridBagConstraints gridBagConstraints = new java.awt.GridBagConstraints();
gridBagConstraints.fill = java.awt.GridBagConstraints.BOTH;
gridBagConstraints.weightx = 1.0;
gridBagConstraints.weighty = 1.0;
frame.add(menuPanel, gridBagConstraints);
frame.add(contentPanel, gridBagConstraints);
You might need to play around a little with the constraints to get it to line up exactly how you want.

Related

How to for loop jPanel in jFrame?

May I know why my jPanel does not appear in the jFrame? I want to make 5 blue jPanel appear in the jFrame but why only 1 blue jPanel appear in my jFrame? Thanks for helping!
public class NewJFrame2 extends javax.swing.JFrame {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
/**
* Creates new form NewJFrame2
*/
public NewJFrame2() {
initComponents();
JPanel[] panelArray = new JPanel[5];
JButton btnArray[] = new JButton[5];
for(int i = 0; i<5;i++)
{
panelArray[i] = new JPanel();
//panelArray[i].setVisible(true);
System.out.println(panelArray[i]);
javax.swing.border.Border border = BorderFactory.createLineBorder(Color.BLUE, 5);
panelArray[i].setBackground(Color.YELLOW);
panelArray[i].setBorder(border);
frame.getContentPane().add(panelArray[i]);
}
frame.setSize(new Dimension(500, 400));
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setTitle("A Simple JFrame");
frame.setVisible(true);
}
As mentioned in the comments you want a LayoutManager.
The current issue is that you are adding all five panels to the exact same space on your frame. To solve this issue you need to provide a structure for the frame to associate different coordinates with different areas.
This answer contains a good jumping off point for you to start to play with layouts in Java.
Using a container JPanel with a BoxLayout -- see comments below for further info :
initComponents();
JPanel[] panelArray = new JPanel[5];
JButton btnArray[] = new JButton[5];
JPanel container = new JPanel(); // Container JPanel
container.setLayout(new BoxLayout(container, BoxLayout.X_AXIS)); // With a BoxLayout
for (int i = 0; i < 5; i++) {
panelArray[i] = new JPanel();
//panelArray[i].setVisible(true);
System.out.println(panelArray[i]);
javax.swing.border.Border border = BorderFactory.createLineBorder(Color.BLUE, 5);
panelArray[i].setBackground(Color.YELLOW);
panelArray[i].setBorder(border);
container.add(panelArray[i]); // Adding 5 JPanels to container JPanel
}
frame.getContentPane().add(container); // Adding container JPanel to JFrame
frame.setSize(new Dimension(500, 400));
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setTitle("A Simple JFrame");
frame.setVisible(true);

How do I create the following GUI in Java Swing?

I want to create the following GUI with Java Swing.
Since I'm not experienced enough with Java Swing, I'm not sure how to exactly recreate that GUI.
I've tried using GridLayout which looks like this:
I've tried other LayoutManagers but due to my inexperience, I couldn't get anything even remotely resembling the GUI I want to achieve.
I probably have to use GridBagLayout but I've tried it and simply wasn't able to get anything done.
I'm not sure how to exactly use GridBagLayout, especially since there is a variance of the amount of colums needed (2, 2 and then 3).
Here is the code used for creating the second GUI:
import java.awt.*;
import javax.swing.*;
public class GUITest extends JFrame {
public GUITest() {
super("Testing Title");
Container pane = getContentPane();
pane.setLayout(new GridLayout(3,1));
pane.add(getHeader());
pane.add(getTextArea());
pane.add(getButtonPanel());
}
public JComponent getHeader() {
JPanel labelPanel = new JPanel();
labelPanel.setLayout(new GridLayout(1,2));
labelPanel.setSize(getPreferredSize());
JLabel labelLocal = new JLabel("Left value: ", JLabel.CENTER);
JLabel labelDB = new JLabel("Right value: ", JLabel.CENTER);
labelPanel.add(labelLocal);
labelPanel.add(labelDB);
return labelPanel;
}
public JComponent getTextArea() {
JPanel textPanel = new JPanel();
textPanel.setLayout(new GridLayout(1,2,5,0));
JTextArea testTextArea = new JTextArea();
testTextArea.setEditable(false);
JScrollPane sp1 = new JScrollPane(testTextArea);
JTextArea testTextArea2 = new JTextArea();
JScrollPane sp2 = new JScrollPane(testTextArea2);
testTextArea2.setEditable(false);
testTextArea.setText("Hello Hello Hello\nTesting!\ntesterino\ntesteroni");
testTextArea2.setText("Hello Hello Hello\nTesting!\ntest\nABC123\ncdef123\nhijk123");
textPanel.add(sp1);
textPanel.add(sp2);
return textPanel;
}
public JComponent getButtonPanel() {
JPanel inner = new JPanel();
inner.setLayout(new FlowLayout((FlowLayout.CENTER),0,100));
inner.add(new JButton("Do something"));
inner.add(new JButton("Do something different"));
inner.add(new JButton("Do something even more different"));
return inner;
}
public static void main(String[] args) {
GUITest e = new GUITest();
e.setSize(700, 500);
e.setVisible(true);
e.setResizable(false);
e.setDefaultCloseOperation(EXIT_ON_CLOSE);
e.setLocationRelativeTo(null);
}
}
I'm thankful for any kind of support!
You could try something like this:
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.awt.*;
public class Example {
public static void main(String[] args) {
JFrame jFrame = new JFrame();
jFrame.setTitle("Testing Title");
jFrame.setLocationRelativeTo(null);
JPanel mainPanel = new JPanel(new BorderLayout());
mainPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
JPanel listPanel = new JPanel(new GridLayout(0, 2, 10, 0));
JPanel leftListPanel = new JPanel(new BorderLayout(0, 10));
JLabel leftLabel = new JLabel("Left value:");
JTextArea leftTextArea = new JTextArea("Hello Hello Hello\nTesting!\ntest");
JScrollPane leftScrollPane = new JScrollPane(leftTextArea);
leftListPanel.add(leftLabel, BorderLayout.NORTH);
leftListPanel.add(leftScrollPane, BorderLayout.CENTER);
JPanel rightListPanel = new JPanel(new BorderLayout(0, 10));
JLabel rightLabel = new JLabel("Right value:");
JTextArea rightTextArea = new JTextArea("Hello Hello Hello\nTesting!\ntest");
JScrollPane rightScrollPane = new JScrollPane(rightTextArea);
rightListPanel.add(rightLabel, BorderLayout.NORTH);
rightListPanel.add(rightScrollPane, BorderLayout.CENTER);
listPanel.add(leftListPanel);
listPanel.add(rightListPanel);
mainPanel.add(listPanel, BorderLayout.CENTER);
JPanel buttonsPanel = new JPanel(new BorderLayout());
buttonsPanel.setBorder(new EmptyBorder(10, 10, 10, 10));
buttonsPanel.add(new JButton("Do something"), BorderLayout.WEST);
buttonsPanel.add(new JButton("Do something different"), BorderLayout.CENTER);
buttonsPanel.add(new JButton("Do something even more different"), BorderLayout.EAST);
mainPanel.add(buttonsPanel, BorderLayout.SOUTH);
jFrame.setContentPane(mainPanel);
jFrame.pack();
jFrame.setVisible(true);
}
}
Explanation:
Firstly I created a main JPanel with a BorderLayout. This JPanel will be split horizontally, the CENTRE component will be another JPanel containing the text areas and labels, and the SOUTH component will be a JPanel containing the buttons.
The JPanel that contains the text areas is given a GridLayout so that it can be easily split vertically, and is also given a hgap of 10 to add some spacing.
The left and right JPanels that are put into that are both the same. They have a BorderLayout with a vgap to add spacing. The NORTH component is a JLabel and the CENTRE component is a JScrollPane containing a JTextArea.
Finally, the SOUTH component of the main JPanel is another JPanel which is given a BorderLayout again. Three JButtons are added with WEST, CENTRE and EAST attributes allocated accordingly.
The overall result looks like:
Here is your code with just some little changes :)
import java.awt.*;
import javax.swing.*;
public class GUITest extends JFrame {
public GUITest() {
super("Testing Title");
Container pane = getContentPane();
pane.setLayout(new BorderLayout());//Modified Layout to BorderLayout
pane.add(getHeader(),BorderLayout.NORTH); //BorderLayout.NORTH
pane.add(getTextArea(),BorderLayout.CENTER);//BorderLayout.CENTER
pane.add(getButtonPanel(),BorderLayout.SOUTH);//BorderLayout.SOUTH
}
public JComponent getHeader() {
JPanel labelPanel = new JPanel();
labelPanel.setLayout(new GridLayout(1,2));
labelPanel.setSize(getPreferredSize());
JLabel labelLocal = new JLabel("Left value: ", JLabel.CENTER);
JLabel labelDB = new JLabel("Right value: ", JLabel.CENTER);
labelPanel.add(labelLocal);
labelPanel.add(labelDB);
return labelPanel;
}
public JComponent getTextArea() {
JPanel textPanel = new JPanel();
textPanel.setLayout(new GridLayout(1,2,5,0));
JTextArea testTextArea = new JTextArea();
testTextArea.setEditable(false);
JScrollPane sp1 = new JScrollPane(testTextArea);
JTextArea testTextArea2 = new JTextArea();
JScrollPane sp2 = new JScrollPane(testTextArea2);
testTextArea2.setEditable(false);
testTextArea.setText("Hello Hello Hello\nTesting!\ntesterino\ntesteroni");
testTextArea2.setText("Hello Hello Hello\nTesting!\ntest\nABC123\ncdef123\nhijk123");
textPanel.add(sp1);
textPanel.add(sp2);
return textPanel;
}
public JComponent getButtonPanel() {
JPanel inner = new JPanel();
inner.setLayout(new FlowLayout());//Modified to standard FlowLayout
inner.add(new JButton("Do something"));
inner.add(new JButton("Do something different"));
inner.add(new JButton("Do something even more different"));
return inner;
}
public static void main(String[] args) {
GUITest e = new GUITest();
e.pack(); //Modified setSize(700,500) to pack()
e.setVisible(true);
e.setResizable(false);
e.setDefaultCloseOperation(EXIT_ON_CLOSE);
e.setLocationRelativeTo(null);
}
}
GridLayout sizes all cells the same, i.e. your outer layout with 3 rows and 1 column makes 3 cells of all the same size.
Instead, use BorderLayout for your outer container and add the top, mid and lower panels with constraints BorderLayout.NORTH, BorderLayout.CENTER and BorderLayout.SOUTH respectively

Java panel alignment

class CipherGUIFrame extends JFrame {
public CipherGUIFrame() {
super("Caesar Cipher GUI");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400, 600);
JTextArea area1 = new JTextArea();
JTextArea area2 = new JTextArea();
JSpinner myspinner=new JSpinner();
JPanel mainframe = new JPanel();
mainframe.setLayout(new BoxLayout(mainframe, BoxLayout.Y_AXIS));
JPanel p1 = new JPanel();
JPanel p2 = new JPanel();
JPanel p3 = new JPanel();
p1.setLayout(new BoxLayout(p1, BoxLayout.Y_AXIS));
p2.setLayout(new BoxLayout(p2, BoxLayout.Y_AXIS));
p1.setBorder(BorderFactory.createTitledBorder("Cleartext"));
p2.setBorder(BorderFactory.createTitledBorder("Spinner"));
p3.setLayout(new BoxLayout(p3, BoxLayout.Y_AXIS));
p3.setBorder(BorderFactory.createTitledBorder("Ciphertext"));
p1.add(area1);
p2.add(myspinner);
p3.add(area2);
mainframe.add(p1);
mainframe.add(p2);
mainframe.add(p3);
this.add(mainframe);
}
}
It seems that this code produces something which looks similar to this:
I am trying to tidy this up so it looks cleaner; is there a way to shrink the middle panel or to make the others bigger to make it look nicer?
Don't set the sizes of anything, but instead set the columns and rows of your JTextAreas. Don't use BoxLayout when you don't want its behaviors. Put your JTextAreas in JScrollPanes instead. And don't forget to pack() your JFrame.
import java.awt.BorderLayout;
import javax.swing.*;
public class Cipher2 extends JPanel {
public static final int ROWS = 12;
public static final int COLS = 30;
private JTextArea textArea1 = new JTextArea(ROWS, COLS);
private JTextArea textArea2 = new JTextArea(ROWS, COLS);
public Cipher2() {
setLayout(new BoxLayout(this, BoxLayout.Y_AXIS)); // Box OK here
JScrollPane scroll1 = new JScrollPane(textArea1);
add(wrapComponentWithTitle(scroll1, "Fubar"), BorderLayout.PAGE_START);
add(wrapComponentWithTitle(new JSpinner(), "Spinner"), BorderLayout.CENTER);
scroll1 = new JScrollPane(textArea2);
add(wrapComponentWithTitle(scroll1, "Snafu"), BorderLayout.PAGE_END);
}
private JPanel wrapComponentWithTitle(JComponent component, String title) {
// BoxLayout NOT OK here. Use BorderLayout instead
JPanel wrapPanel = new JPanel(new BorderLayout());
wrapPanel.add(component);
wrapPanel.setBorder(BorderFactory.createTitledBorder(title));
return wrapPanel;
}
private static void createAndShowGui() {
Cipher2 mainPanel = new Cipher2();
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
I figured out the answer: change Y_AXIS to X_AXIS.
<3

Java BoxLayout alignment issue

Can anyone help me. Why is the Label "Current" NOT left aligned in Panel/Frame?
public static void main(String[] args) {
JFrame TFrame = new JFrame("Test DisplayLayout");
TFrame.setResizable(true);
TFrame.setSize(new Dimension(900, 840));
TFrame.setLocationRelativeTo(null);
TFrame.setTitle("DisplayLayout");
TFrame.setVisible(true);
JPanel P = DisplayLayout2();
P.setVisible(true);
P.setOpaque(true);
P.setLayout(new BoxLayout(P, BoxLayout.Y_AXIS));
TFrame.add(P);
TFrame.revalidate();
TFrame.repaint();
}
public static JPanel DisplayLayout2() {
JPanel Panel=new JPanel();
Panel.setVisible(true);
Panel.setOpaque(true);
Panel.setLayout(new BoxLayout(Panel, BoxLayout.Y_AXIS));
Panel.setAlignmentX(Component.LEFT_ALIGNMENT);
JLabel lab = new JLabel("Current");
lab.setHorizontalAlignment(SwingConstants.LEFT);
lab.setForeground(Color.WHITE);
lab.setBackground(Color.PINK);
lab.setOpaque(true);
Panel.add(lab,Component.LEFT_ALIGNMENT);
JPanel posPanel = new JPanel();
JScrollPane scrollPane = new JScrollPane(posPanel,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
scrollPane.setPreferredSize(new Dimension(290, 200));
scrollPane.setOpaque(true);
posPanel.setBackground(Color.YELLOW);
posPanel.setPreferredSize(new Dimension(290, 200));
posPanel.setLayout(new BoxLayout(posPanel, BoxLayout.Y_AXIS));
posPanel.setAlignmentX(Component.LEFT_ALIGNMENT);
Panel.add(scrollPane);
return Panel;
}
This is one of the quirks of the BoxLayout (well, quirk to me, but it is a documented expected behavior of the layout), and I'm forgetting off the top of my head why it does this, but I do know of at least one way around it: put your JLabel into a JPanel that uses FlowLayout.LEFT (or LEADING), and add that to your BoxLayout-using container:
JPanel labPanel = new JPanel(new FlowLayout(FlowLayout.LEFT, 0, 0));
labPanel.add(lab);
panel.add(labPanel, Component.LEFT_ALIGNMENT);
Note, that I believe that it has something to do with the JLabel not wanting to expand while the JPanel that encloses it does, but don't quote me on that.
Edit
From the BoxLayout Tutorial:
For a top-to-bottom box layout, the preferred width of the container is that of the maximum preferred width of the children. If the container is forced to be wider than that, BoxLayout attempts to size the width of each component to that of the container's width (minus insets). If the maximum size of a component is smaller than the width of the container, then X alignment comes into play.
You could probably solve this by setting both the JLabel's and the JScrollPane's x-alignment to Component.LEFT_ALIGNMENT. Your current code forgets to set the JScrollPane's x-alignment, and that's where your trouble lies:
scrollPane.setAlignmentX(Component.LEFT_ALIGNMENT);
For example:
import java.awt.*;
import javax.swing.*;
public class Foo2 {
private static void createAndShowGui() {
JLabel topLabel = new JLabel("Top Label", SwingConstants.LEFT);
topLabel.setOpaque(true);
topLabel.setBackground(Color.pink);
JScrollPane scrollpane = new JScrollPane(
Box.createRigidArea(new Dimension(400, 400)),
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
JPanel mainPanel = new JPanel();
mainPanel.setLayout(new BoxLayout(mainPanel, BoxLayout.PAGE_AXIS));
topLabel.setAlignmentX(Component.LEFT_ALIGNMENT);
mainPanel.add(topLabel);
scrollpane.setAlignmentX(Component.LEFT_ALIGNMENT);
mainPanel.add(scrollpane);
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
This results in:
Use constant into Component(Left,Right,Center)

Not all components showing

When I run this program, the window blocks out the buttons in panel2 when I use setSize to determine window size.
In addition, if I use frame.pack() instead of setSize(), all components are on one horizontal line but I'm trying to get them so that panel1 components are on one line and panel2 components are on a line below them.
Could someone explain in detail the answers to both of these problems?
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Exercise16_4 extends JFrame{
// FlowLayout components of top portion of calculator
private JLabel jlbNum1 = new JLabel("Number 1");
private JTextField jtfNum1 = new JTextField(4);
private JLabel jlNum2 = new JLabel("Number 2");
private JTextField jtfNum2 = new JTextField(4);
private JLabel jlbResult = new JLabel("Result");
private JTextField jtfResult = new JTextField(8);
// FlowLayout Components of bottom portion of calculator
private JButton jbtAdd = new JButton("Add");
private JButton jbtSubtract = new JButton("Subtract");
private JButton jbtMultiply = new JButton("Multiply");
private JButton jbtDivide = new JButton("Divide");
public Exercise16_4(){
JPanel panel1 = new JPanel();
panel1.setLayout(new FlowLayout(FlowLayout.CENTER, 3, 3));
panel1.add(jlbNum1);
panel1.add(jtfNum1);
panel1.add(jlNum2);
panel1.add(jtfNum2);
panel1.add(jlbResult);
panel1.add(jtfResult);
JPanel panel2 = new JPanel();
panel2.setLayout(new FlowLayout(FlowLayout.CENTER, 3, 10));
panel1.add(jbtAdd);
panel1.add(jbtSubtract);
panel1.add(jbtMultiply);
panel1.add(jbtDivide);
add(panel1, BorderLayout.NORTH);
add(panel2, BorderLayout.CENTER);
}
public static void main(String[] args){
Exercise16_4 frame = new Exercise16_4();
frame.setTitle("Caculator");
frame.setSize(400, 200);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//frame.setResizable(false);
frame.setVisible(true);
}
}
You're problem is likely a typographical error in that you're adding all components to panel1 and none to panel2:
// you create panel2 just fine
JPanel panel2 = new JPanel();
panel2.setLayout(new FlowLayout(FlowLayout.CENTER, 3, 10));
// but you don't use it! Change below to panel2.
panel1.add(jbtAdd);
panel1.add(jbtSubtract);
panel1.add(jbtMultiply);
panel1.add(jbtDivide);
Add the buttons to panel2, and then call pack() before setVisible(true). Do not set the size of the GUI.

Categories