I have a JDialog with a title written at the top. I call this JDialog for two different cases and if it is not the default I change the text to something else. This works fine but the position is then too far to the right.
I have tried numerous methods such as:
TitleText.setText("Edit Fuse");
TitleText.setAlignmentY(JLabel.CENTER_ALIGNMENT);
//TitleText.setHorizontalAlignment(JDialog.);
//TitleText.setLayout(new FlowLayout(FlowLayout.LEFT));
None of them even move the text. I am using a Free Design Layout for the entire JDialog. If I must I'll just create another JLable and hide/unhide but I thought this would be simple. Anyone know how to do this?
I am using a Free Design Layout for the entire JDialog
Don't do this if you want the title JLabel's text to be at the top and be centered. Instead have the JDialog's main JPanel use BorderLayout, and add the JLabel to it BorderLayout.PAGE_START, also known as BorderLayout.North.
The main JPanel can then hold the rest of your GUI, likely in its own JPanel, using its own layout manager, and other JPanels, in its BorderLayout.CENTER position.
Also, don't use JLabel.CENTER_ALIGNMENT, a float, but rather use JLabel.CENTER, an int, which is the appropriate parameter for the setHorizontalAlignment(...) method.
Finally, I must give you an unsolicitated side recommendation to be sure that your variable names begin with a lower-case letters and not upper case letters so that they comply with Java naming rules. This is important if you want others, such as folks here who'd like to help you, to rapidly understand your code.
For example:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
#SuppressWarnings("serial")
public class LayoutExample extends JPanel {
private static final float SIZE = 32;
private static final int TIMER_DELAY = 2000;
private String[] TITLE_STRINGS = { "Title 1", "Title 2",
"Some Random Title", "Fubars Rule!", "Snafus Drool!" };
private int titleIndex = 0;
private JLabel titleLabel = new JLabel(TITLE_STRINGS[titleIndex],
JLabel.CENTER);
public LayoutExample() {
titleLabel.setFont(titleLabel.getFont().deriveFont(Font.BOLD, SIZE));
setLayout(new BorderLayout());
add(titleLabel, BorderLayout.PAGE_START);
// the rest of your GUI could be added below
add(Box.createRigidArea(new Dimension(500, 300)), BorderLayout.CENTER);
new Timer(TIMER_DELAY, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
titleIndex++;
titleIndex %= TITLE_STRINGS.length;
titleLabel.setText(TITLE_STRINGS[titleIndex]);
}
}).start();
}
private static void createAndShowGui() {
JFrame frame = new JFrame("LayoutExample");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new LayoutExample());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Related
I'm trying to add the JScrollPane to my JTextArea, but somehow, it won't appear.
I've tried resizing it according to the dimension of the JTextArea, but it doesn't seem to work. Also, notice that I'm using the null layout because I want the full-on flexibility of displaying certain buttons and panels at a pinpoint location.
import java.awt.Dimension;
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JButton;
import javax.swing.JScrollPane;
import javax.swing.ScrollPaneConstants;
import javax.swing.JTextArea;
public class PaneTester{
private static JFrame frame;
private static JPanel panel;
private static JScrollPane scrollPane;
private static JTextArea notificationBox;
public static void main (String [] args){
stage1();
stage2();
}
private static void stage1(){
createFrame();
createPanel();
frame.getContentPane().add(panel);
panel.setVisible(true);
frame.setVisible(true);
}
private static void stage2(){
generateNotificationBox();
}
private static void createFrame(){
frame = new JFrame();
frame.setSize(new Dimension(900,700));
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(true);
}
private static void createPanel(){
panel = new JPanel();
panel.setLayout(null);
generateGridButtons();
}
private static void generateGridButtons(){
short y = 0;
for(short i=0;i<4;i++){
y += 60;
short x = 500;
for(short j=0;j<5;j++){
JButton gridButton = new JButton();
gridButton.setBounds(x, y,120,60);
panel.add(gridButton);
x += 140;
}
}
}
public static void generateNotificationBox(){
notificationBox = new JTextArea(10,10);
notificationBox.setBounds(25, 25, 200, 400);
scrollPane = new JScrollPane(notificationBox, ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS,
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS );
Dimension d = new Dimension(notificationBox.getPreferredSize());
scrollPane.getViewport().setPreferredSize(d);
scrollPane.getViewport().add(notificationBox);
panel.add(notificationBox);
panel.repaint();
}
}
Stop mucking with setBounds and setPreferredSize, you're just making live more difficult for your self.
If you want to affect the size of JTextArea (and the viewable area of the JScrollPane) have a look at the JTextArea constructor JTextArea(int rows, int columns), which will allow you to specify the number of rows/columns you want the JTextArea to default to, and which will allow the JTextArea to calculate it's preferredSize based on the current font's metrics in more stable cross platform way
Your core problem, however, is right here...
scrollPane.getViewport().add(notificationBox);
panel.add(notificationBox);
You add the notificationBox to the JScrollPanes JViewport, which is good, but then you add notificationBox to the panel, which will remove it from the JScrollPane's JViewport, which is bad
Instead, add the JScrollPane to the panel
scrollPane.getViewport().add(notificationBox);
panel.add(scrollPane);
You're also making overuse of static. I'd highly recommend you take the time to reduce static down to it's absolute minimum required usage, this will probably mean that rather then constructing the UI in the main method, you have a "main" class which you can insatiate (from main) which will perform the initial setup - IMHO
I've tried that. I think someone else suggested that from another post, but when I tried that, it just took away the JTextArea completely from the panel
Get rid of panel.setLayout(null); and start making use of appropriate layout managers and compound layouts. Start by having look at Laying Out Components Within a Container for more details
I have sub-classed JPanel to provide a generic JPanel container that contains options for a filter selected from a JComboBox.
When the JComboBox is changed from one filter to another, I have a switch statement that checks which filter is now selected and reassigns the "options" JPanel to a new instance of the options class associated with that filter:
public void setFilterOptions(String choice){
switch(choice){
case "Gaussian": options = new GaussianFilterOptions();break;
case "Sobel": options = new SobelFilterOptions();System.out.println("?");break;
}
}
The problem is that the JPanel "options" does not get refreshed in the GUI after setFilterOptions is called. Whichever filter is set to show by default appears upon startup and remains even if I switch the JComboBox selection. I have tried repainting, revalidating, and validating "options" as well as the JPanel containing "options" and the JFrame enclosing the entire application.
I added print statements in each case to verify that they were working when the combo box is switched and not falling through, so I'm sure that is not the problem.
You're confusing variable with object. You have likely originally placed a JPanel object that options referred to into your GUI, but understand, you didn't place the options variable into the GUI, but rather (and again) the JPanel object that it referred to into the GUI.
If later you change the JPanel that the options variable refers to, this will have no effect on the GUI, since it still holds the same original JPanel object that it held before. If you want to change the JPanel displayed, you have to do that directly by swapping out JPanels in the GUI. This is best accomplished by using a CardLayout.
e.g.,
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class SwapPanels extends JPanel {
private static final String GAUSSIAN = "Gaussian";
private static final String SOBEL = "Sobel";
private static final String[] FILTER_OPTIONS = {GAUSSIAN, SOBEL};
private CardLayout cardLayout = new CardLayout();
private JPanel cardHolderPanel = new JPanel(cardLayout);
private JPanel gaussianPanel = new JPanel();
private JPanel sobelPanel = new JPanel();
private JComboBox<String> filterCombo = new JComboBox<>(FILTER_OPTIONS);
public SwapPanels() {
JPanel comboPanel = new JPanel();
comboPanel.add(filterCombo);
filterCombo.addActionListener(new ComboListener());
gaussianPanel.add(new JLabel("Gaussian Filtering Done Here"));
sobelPanel.add(new JLabel("Sobel Filtering Done Here"));
cardHolderPanel.add(gaussianPanel, GAUSSIAN);
cardHolderPanel.add(sobelPanel, SOBEL);
int gap = 50;
cardHolderPanel.setBorder(BorderFactory.createEmptyBorder(gap, gap, gap, gap));
setLayout(new BorderLayout());
add(cardHolderPanel, BorderLayout.CENTER);
add(comboPanel, BorderLayout.PAGE_END);
}
private class ComboListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
String key = (String) filterCombo.getSelectedItem();
cardLayout.show(cardHolderPanel, key);
}
}
private static void createAndShowGui() {
SwapPanels mainPanel = new SwapPanels();
JFrame frame = new JFrame("SwapPanels");
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();
}
});
}
}
Also you could do it like this instead of the switch
public void setFilterOptions(String choice){
options = (choice.equals("Gaussian"))? new GaussianFilterOptions():
new SobelFilterOptions();
}
}
I want to put my background image at the very bottom in this frame, and the button on top. However the code I wrote below doesn't work. Can anyone see where the problems are?
Another thing is that even though I set the location for my button, it keep showing at the top center on the frame.
Please ignore the comment lines. (I was just guessing, and hoping them will work, but they don't apparently.)
public class Menu extends JFrame{
private JLayeredPane pane;
private JLayeredPane pane2;
public Menu(){
final JFrame f = new JFrame("Chinese Chess");
JButton play = new JButton("Play vs. AI");
f.setLayout(new FlowLayout());
f.setLocationRelativeTo(null);
f.setSize(800, 800);
f.setVisible(true);
f.setResizable(false);
//f.pack();
pane = new JLayeredPane();
pane2 = new JLayeredPane();
f.add(pane);
f.add(pane2);
//background image
JLabel background = new JLabel(new ImageIcon("res/img/background.png"));
background.setLocation(0, 0);
background.setSize(800, 800);
pane.add(background, JLayeredPane.FRAME_CONTENT_LAYER);
pane2.add(play, JLayeredPane.DEFAULT_LAYER);
//pane.moveToBack();
//button PlayAI
play.setLocation(500,500);
play.setPreferredSize(new Dimension(100,50));
//f.setLayout(new FlowLayout());
//frame menu
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//f.getContentPane().add(play);
play.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
new PlayAI();
}
});
}
public static void main(String[] args){
new Menu();
}
Problems/Solutions:
setLocation(...) and setBounds(...) types of calls are ignored by most layout managers. The only way to use them is to set the layout of the container to null via .setLayout(null);
But having said that, while null layouts and setBounds() might seem to Swing newbies like the easiest and best way to create complex GUI's, the more Swing GUI'S you create the more serious difficulties you will run into when using them. They won't resize your components when the GUI resizes, they are a royal witch to enhance or maintain, they fail completely when placed in scrollpanes, they look gawd-awful when viewed on all platforms or screen resolutions that are different from the original one.
So in sum -- don't do this, don't use null layouts or setBounds, but rather nest JPanels, each using its own layout manager, and thereby create easy to maintain and decent GUI's.
If you want an image to be in the background, then draw it in a JPanel that you use as a container for your GUI components by drawing it in the JPanel's paintComponent(Graphics g) method as has been demonstrated in many many similar questions on this site -- I'll find you some of mine in a second.
If you add any JPanels on top of this image drawing JPanel, be sure that you can see through them by calling setOpaque(false) on these overlying JPanels. Otherwise you'll cover up the image.
Your code has two JFrames when only one is needed. Get rid of the one you don't use.
You call setVisible(true) too early on the JFrame, before components have been added to the GUI -- don't. Call it only after adding everything to the GUI so all display OK.
You're creating two JLayedPanes, and completely covering one by the other by adding them to the JFrame without understanding how the JFrame's BorderLayout handles added components.
I suggest that you not even use one JLayeredPane but instead draw in the JPanel as noted above, and use that as your container.
Your code looks to be opening a completely new GUI window when the play button is pressed, and if so, this can get annoying to the user fast. Consider swapping views instead with a CardLayout.
For example:
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
// extend JPanel so you can draw to its background
#SuppressWarnings("serial")
public class Menu2 extends JPanel {
private BufferedImage bgImage = null; // our background image
private JButton playButton = new JButton(new PlayVsAiAction("Play Vs. AI", KeyEvent.VK_P));
public Menu2(BufferedImage bgImage) {
this.bgImage = bgImage;
setLayout(new GridBagLayout()); // center our button
add(playButton);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (bgImage != null) {
g.drawImage(bgImage, 0, 0, this);
}
}
// to size our GUI to match a constant or the image.
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
// if you want to size it based on the image
if (bgImage != null) {
int width = bgImage.getWidth();
int height = bgImage.getHeight();
return new Dimension(width, height);
} else {
return super.getPreferredSize();
}
// if you want to size the GUI with constants:
// return new Dimension(PREF_W, PREF_H);
}
private class PlayVsAiAction extends AbstractAction {
public PlayVsAiAction(String name, int mnemonic) {
super(name); // have our button display this name
putValue(MNEMONIC_KEY, mnemonic); // alt-key to press button
}
#Override
public void actionPerformed(ActionEvent e) {
// TODO code to start program
}
}
private static void createAndShowGui() {
BufferedImage img = null;
String imagePath = "res/img/background.png";
try {
// TODO: fix this -- use class resources to get image, not File
img = ImageIO.read(new File(imagePath));
} catch (IOException e) {
e.printStackTrace();
System.exit(-1);
}
Menu2 mainPanel = new Menu2(img);
JFrame frame = new JFrame("Chinese Chess");
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(() -> {
createAndShowGui();
});
}
}
Apart from the solution above... you should create and launch your swing application this way:
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
private static void createAndShowGUI() {
// Instantiate your JFrame and show it
}
When you choose a state, the frame's content pane removes its components. Then depending on the state you chose, another class takes the content pane and adds onto it. After doing so, the frame gets packed to resize accordingly.
I want free control over whats in the Frame, such as being able to put panels side by side, above one another, ect.. so I really don't want to use CardLayout. (I'd much rather have 1 panel handle both loginscreen and chat. Then, be able to display another panel next to that one).
I'm using the JFrame's content pane for my login and chat screen, but when I run my code, I get a small frame (has SOME size, but hardly any) that's white on the inside.
show frame
switch to chat
remove everything on pane (currently nothing)
add components onto pane
pack frame so it can size accordingly to the pane
revalidate if needed (not sure when I need to revalidate or not)
Please tell me what I'm doing wrong, and maybe guide me in the right direction.
PS: There are no errors
EDIT: The only thing I can think of is that since I'm passing frame.getContentPane() through the method, and methods are pass-by-value, the actual reference to frame.getContentPane() might not be noticing the changes I'm asking for. But then I don't know why the inside of the frame would be white (as if my JTextArea tried rendering), and there's padding on the inside of the frame, so there has to be something happening..
Main.java:
package main;
import ui.Frame;
public class Main {
public static Frame frame = new Frame();
public static void main(String[] args) {
frame.show();
frame.switchState(State.chat);
}
public static enum State {
login, chat;
}
}
Frame.java:
package ui;
import main.Main.State;
import javax.swing.JFrame;
public class Frame {
private Panel currentpanel; //from package ui, not AWT
private ChatPanel chatpanel = new ChatPanel();
private JFrame frame;
public Frame() {
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
}
public void show() {
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public void switchState(State state) {
frame.removeAll();
switch(state) {
case chat:
currentpanel = chatpanel;
currentpanel.addComponentsTo(frame.getContentPane());
break;
}
frame.pack();
frame.revalidate();
}
}
Panel.java:
package ui;
import java.awt.Container;
public interface Panel {
public void addComponentsTo(Container pane);
}
ChatPanel.java:
package ui;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JTextArea;
public class ChatPanel implements Panel {
private JTextArea toparea = new JTextArea();
private JTextArea bottomarea = new JTextArea();
#Override
public void addComponentsTo(Container pane) {
pane.setPreferredSize(new Dimension(500, 500));
pane.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridy = 0;
gbc.gridx = 0;
gbc.ipadx = 450;
gbc.ipady = 350;
pane.add(toparea, gbc);
gbc.gridy = 1;
gbc.ipady = 100;
pane.add(bottomarea);
}
}
I know that can be quite frustrating.
have you tried calling
pack(); or repaint();
I found the problem. It was calling frame.removeAll(); before adding anything to it.
When I tried if(frame.getComponents().length > 0), it still triggered removeAll(), but the problem wasn't fixed. Seeing how I haven't added anything yet, I checked to see what the component was (by printing out the object), and it was a JRootPane.
After that, I tried printing out frame.getContentPane().getComponents().length, it gave me 0 as expected.
Long story short: This is how switchPanel(State state) should look:
public void switchState(State state) {
if(frame.getContentPane().getComponents().length > 0)
frame.removeAll();
switch(state) {
case chat:
currentpanel = chatpanel;
currentpanel.addComponentsTo(frame.getContentPane());
break;
}
frame.pack();
frame.revalidate();
}
NOTE: I still recommend CardLayout, but if you insists in dynamically setting the frame's content pane the here it is.
The frame class
public class SwitchingFrame extends JFrame {
public static enum State {ONE, TWO}
private PanelONE panel1 = new PanelONE();
private PanelTWO panel2 = new PanelTWO();
public SwitchingFrame() {
getContentPane().setLayout(new BorderLayout());
pack();
setVisible(true);
}
public void switchState(State state) {
setVisible(false);
getContentPane().removeAll();
if (state.equals(State.ONE))
getContentPane().add(panel1, BorderLayout.CENTER);
else
getContentPane().add(panel2, BorderLayout.CENTER);
pack();
setVisible(true);
}
}
The two panel classes which are switched
public class PanelONE extends JPanel {
public PanelONE() {
add(new JLabel("ONE"));
}
}
public class PanelONE extends JPanel {
public PanelTWO() {
add(new JLabel("TWO"));
}
}
The main method which includes buttons to simulate changing the panels
public class TestSwitchingFrame {
public static void main(String[] args) {
final SwitchingFrame sframe = new SwitchingFrame();
JFrame frame = new JFrame();
JButton b1 = new JButton("ONE");
b1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
sframe.switchState(SwitchingFrame.State.ONE);
}
});
JButton b2 = new JButton("TWO");
b2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
sframe.switchState(SwitchingFrame.State.TWO);
}
});
frame.getContentPane().setLayout(new FlowLayout());
frame.getContentPane().add(b1);
frame.getContentPane().add(b2);
frame.pack();
frame.setVisible(true);
}
}
You do not need (not should) write your own interface (Panel). Your two panels should extend JPanel and set within the frames content pane. Your frame should extend JFrame and does not need to override its show method (let Swing do it for you). The specific implementation of the switchState function should eventually depend on the end result you want. There are similar ways to accomplish almost the same result.
Is it possible to create a JLabel with a right-justified icon and text and the icon is on the right, like this:
I've seen this question, but is it really the best approach?
Perhaps this would be more what you're looking for? It should align everything on the right side of the panel (more so than the example you were looking at):
import java.awt.*;
import javax.swing.*;
public class TempProject
{
public static void main(String args[])
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
Box mainContent = Box.createVerticalBox();
mainContent.add(TempProject.getLabel("abc"));
mainContent.add(TempProject.getLabel("Longer"));
mainContent.add(TempProject.getLabel("Longerest"));
mainContent.add(TempProject.getLabel("Smaller"));
JFrame frame = new JFrame();
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.setContentPane(mainContent);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public static JLabel getLabel(String text){
JLabel c = new JLabel(text);
c.setHorizontalTextPosition(SwingConstants.LEADING);
c.setAlignmentX(SwingConstants.RIGHT);
c.setIcon(UIManager.getIcon("FileChooser.detailsViewIcon"));
return c;
}
}
The example cited uses layout and label properties for right/left justification.
Additionally, consider implementing the Icon interface in a JList renderer, where setHorizontalAlignment() and setVerticalAlignment() may be used to control the relative geometry. This related TableCellRenderer illustrates the principle.