I have a JLabel that contains variable text in a certain location in my GUI. The problem is that the text gets displayed at the bottom of the space where the JLabel is located. This does not convey to the end user the relevant information about the other contents of the GUI. Instead, I need the text of the JLabel to be printed in the middle of the vertical axis of the JLabel. A simplified version of my code is below. Can anyone show me how to alter it so that the text displays in the middle of the vertical axis instead of the bottom?
Main.java:
import java.awt.*;
import javax.swing.*;
public class Main {
public static void main(String[] args) {
JFrame frame = new JFrame("Main");
frame.getContentPane().setLayout(new FlowLayout());
frame.getContentPane().add(new VerticalLabel("Hello"));
Dimension prefSize = new Dimension(400, 300);
frame.setPreferredSize(prefSize);
frame.setMinimumSize(prefSize);
frame.pack();
frame.setVisible(true);
}
}
VerticalLabel.java:
import javax.swing.*;
import java.awt.*;
import javax.swing.border.EtchedBorder;
public class VerticalLabel extends JLabel {
public VerticalLabel(String labelText) {
Dimension myDim = new Dimension(15, 250);
this.setPreferredSize(myDim);
this.setHorizontalAlignment(LEFT);
this.setVerticalAlignment(CENTER);
this.setText(labelText);
this.setVerticalTextPosition(CENTER);
this.setUI(new VerticalLabelUI(false));
this.setBorder(new EtchedBorder());
}
}
Hardcoding a random preferred size is not a good idea.
You wrote a custom UI, so it is the responsibility of the UI to paint the text in the proper position.
Instead of creating a custom UI you can use the Text Icon approach to display vertical text. Create the label as follows:
JLabel label = new JLabel();
label.setHorizontalAlignment(JLabel.CENTER);
TextIcon labelIcon = new TextIcon(label, "Hello", TextIcon.Layout.VERTICAL);
label.setIcon( vIcon );
Add the label to the CENTER of a panel using a BorderLayout and the vetical text will be centered vertically and horizontally.
import javax.swing.*;
import java.awt.*;
import javax.swing.border.EtchedBorder;
public class VerticalLabel extends JLabel{
public VerticalLabel(String labelText){
this.setHorizontalAlignment(LEFT);
this.setVerticalAlignment(CENTER);
this.setText(labelText);
this.setVerticalTextPosition(CENTER);
//this.setUI( new VerticalLabelUI(false) );
this.setBorder( new EtchedBorder() );
}
public static void main(String[] args){
// should be done on the EDT.
JFrame frame = new JFrame("Main");
frame.getContentPane().setLayout( new GridBagLayout() );
frame.getContentPane().add(new VerticalLabel("Hello"));
Dimension prefSize = new Dimension(200,150);
frame.setPreferredSize(prefSize);
frame.setMinimumSize(prefSize);
frame.pack();
frame.setVisible(true);
}
}
Related
I'm fairly new to coding and was trying to make a simple GUI with JAVA Swing. I wanted to place an image in a label but for some reason does the image does not show when I run the Code. Are there some requirements I don't know of or did I do something wrong?
package Part2Lables;
import javax.swing.*;
public class Main {
public static void main(String[] args) {
//Label = a GUI display area for a string of text, an image, or both
ImageIcon image = new ImageIcon("Kakashi.png");
JLabel label = new JLabel(); // create a label
label.setText("This is text in a label"); // set text to the label
label.setIcon(image);
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setSize(500,500);
frame.setVisible(true);
frame.add(label);
}
}
This is the code I used (I did use imports but they are not visible in the pic.)
I am having trouble implementing JLabel with JFrame. The program needs to show either "Hello" or "World" in the center of the screen when the button "study" is pressed. Also with this being a flashcard program, when study is pressed a word is placed on the middle of the screen and the program is suppose to read from the text field for the user input and print whether it is right or wrong. The problem is that the program is reading the text field after study is pressed so it is printing false before the user can input a answer.
Can someone briefly explain why this is not working and what I can do to fix this issue?
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.JButton;
public class NoteCardGUI implements ActionListener {
public static JFrame frame;
public static JPanel panel;
public static JLabel label;
private NoteCard ex;
private JButton study;
public static Box box1 = new Box(), box2 = new Box(), box3 = new Box();
public NoteCardGUI() {
ex = new NoteCard("Hello", "World");
frame = new JFrame("Flash Card");
panel = new JPanel();
study = new JButton("Study");
study.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String resp = NoteCard.getResponse(ex);
String chal = NoteCard.getChallenge(ex);
String a = text.getText();
label = new JLabel(chal, label.CENTER);
label.setAlignmentX(0);
label.setAlignmentY(0);
frame.add(label, BorderLayout.SOUTH);
frame.revalidate();
if(resp.compareTo(a) == 0)
{
label = new JLabel("Correct!");
}
label = new JLabel("Incorrect");
}
});
panel.add(study);
frame.add(panel);
frame.setSize(500, 500);
frame.setResizable(false);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
new NoteCardGUI();
}
#Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
}
}
You are adding the label to your frame, but you already have added a JPanel on top of the frame. The solution is to add the label to the panel instead of the frame.
So change: frame.add(label); to panel.add(label);
By default, a JFrame (or rather, its content pane) has BorderLayout. This means that if you add components to it without specifying a constraint, they will be added at the CENTER. But you can't add more than one element at any of the BorderLayout's regions.
So in order for this to work, you need to add the label somewhere else other than the center, or have the panel added with some other, explicit region.
So if you change the add, for example, to:
frame.add(label, BorderLayout.NORTH);
It will work - but you must not forget to also add:
frame.revalidate();
Whenever you add components to your GUI, you should call this when you've added them all, in order for it to rebuild the hierarchy of components as needed.
Another option would be to change the layout manager of the Frame, or to add to the panel.
I'm trying to align a JLabel to the right in a JPanel. I'm adding a JTabbedPane, a JPanel which contains my JLabel and JTextArea to a main JPanel.
I have searched SO and tried some methods like setAlignmentX, setHorizontalAlignment(SwingConstants.LEFT) and nested containers to no avail.
Here's my code:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class LabelProblem
{
public static void main(String[] args)
{
JFrame frame = new JFrame("Label Problem");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel Main = new JPanel();
Main.setLayout(new BoxLayout(Main, BoxLayout.Y_AXIS));
JPanel ComponentPanel = new JPanel();
JLabel label = new JLabel("Sample Text");
label.setHorizontalAlignment(SwingConstants.LEFT);
label.setBorder(BorderFactory.createLineBorder(Color.BLACK));
label.setAlignmentX(Component.RIGHT_ALIGNMENT);
ComponentPanel.add(label);
JTabbedPane Tab = new JTabbedPane();
Tab.add("Document 1", new JPanel());
Main.add(Tab);
Main.add(ComponentPanel);
JTextArea Area = new JTextArea(10,10);
JScrollPane Scroll = new JScrollPane(Area);
frame.add(Main);
frame.add(Scroll, BorderLayout.SOUTH);
frame.setSize(450,450);
frame.setVisible(true);
}
}
How can I align my JLabel to the right?
Thanks!
So, the place of that label is determined by the layout of ComponentPanel. Since you didn't specify any layout it is using the default FlowLayout with a CENTER alignment. Assuming that you are ok with a FlowLayout it is a mere question of setting the alignment of the LEFT since this is possible with this layout.
Here's the code with the fix, however I suspect that as you put more elements to the ComponentPanel you will want to use another layout since FlowLayout is more adequate for menus and the like and not for displaying the main content.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.FlowLayout;
import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
class LabelProblem
{
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
initGUI();
}
});
}
public static void initGUI()
{
JFrame frame = new JFrame("Label Problem");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel main = new JPanel();
main.setLayout(new BoxLayout(main, BoxLayout.Y_AXIS));
JPanel componentPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
JLabel label = new JLabel("Sample Text");
label.setBorder(BorderFactory.createLineBorder(Color.BLACK));
componentPanel.add(label);
JTabbedPane Tab = new JTabbedPane();
Tab.add("Document 1", new JPanel());
main.add(Tab);
main.add(componentPanel);
JTextArea area = new JTextArea(10, 10);
JScrollPane scroll = new JScrollPane(area);
frame.add(main);
frame.add(scroll, BorderLayout.SOUTH);
frame.setSize(450, 450);
frame.setVisible(true);
}
}
Result:
Note: I also changed the variable names to follow the java style convention: variable names should start with lower case to differenciate them from clases names, starting in upper case.
One simple approach is to set the label's horizontalAlignment to JLabel.RIGHT in the constructor.
import java.awt.*;
import javax.swing.*;
class LabelProblem {
public static void main(String[] args) {
JFrame frame = new JFrame("Label Problem");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridLayout(0, 1));
JTabbedPane tab = new JTabbedPane();
tab.add("Document 1", new JPanel());
frame.add(tab);
JLabel label = new JLabel("Sample Text", JLabel.RIGHT);
frame.add(label);
JTextArea area = new JTextArea(10, 10);
JScrollPane scroll = new JScrollPane(area);
frame.add(scroll);
frame.pack();
frame.setSize(450, 450);
frame.setVisible(true);
}
}
I think it may be a matter of you not actually setting layouts where you imagine you're setting layouts.
You have a JPanel with a vertically oriented BoxLayout (Main) enclosing another JPanel with default layout (ComponentPanel), finally enclosing your label. The reason why your label can't be pushed to the right is because is already is pushed to the right within it's enclosing container. If you set a colored border around ComponentPanel, you'll see what I mean -- it only occupies the same amount of space as the JLabel, giving the JLabel nowhere to move.
You need to set a layout and constraints for your intermediate ComponentPanel, allowing it to horizontally fill its parent container so that the label has someplace to go.
You haven't really specified how your layout is supposed to look, but if you change the layout on Main to X_AXIS, your label will pop over to the left (as will its parent container). Without knowing what you're really trying to do, I can't say much more.
I would however, suggest you throw your BoxLayout away entirely and look into using GridBagLayout, which gives you a high level control over your UI. GridBagLayout isn't the most concise construct, but that's the price of control.
I want to create a Window with an image and a text so far i've got this:
public void ShowPng1() {
ImageIcon theImage = new ImageIcon("Icon_Entry_21.gif");
panel.setSize(270, 270);
JLabel label = new JLabel("Hello, World!");
JLabel imageLabel = new JLabel(theImage);
imageLabel.setOpaque(true);
panel.add(imageLabel);
panel.add(label);
panel.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.setVisible(true);
}
My panel:
private JFrame panel = new JFrame();
For some reason it won't load nor image nor text, it just pops up as a white window. What can be the problem? I've also tried changing the format to .png, didn't work.
UPDATE
import java.awt.BorderLayout;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class Img {
private JFrame panel = new JFrame();
public Img(){
ShowPng1();
}
public void ShowPng1() {
ImageIcon theImage = new ImageIcon("Icon_Entry_21.gif");
panel.setSize(300, 300);
panel.setResizable(false);
JLabel label = new JLabel("Hello, World!");
JLabel imageLabel = new JLabel(theImage);
imageLabel.setOpaque(true);
panel.add(imageLabel);
panel.add(label, BorderLayout.PAGE_END);
panel.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.setVisible(true);
}
public static void main(String[] args) {
new Img();
}
}
I've managed to get this working, which is ridiculous because I can't figure out how to make it work with my program. Reimeus gave me an idea on creating this script separately, the fix and that worked. I will have to look through my entire program to see if I'm missing anything. Creating it in a separate class should work as well.
it just pops up as a white window
Sounds like you're blocking the EDT on startup. You may need to use one of Swing's concurrency mechanisms to solve it. Post a Minimal, Complete, Tested and Readable example so we can determine this for sure.
In the meantime...
You're displacing the component containing the theImage component in the BorderLayout.CENTER location
panel.add(label);
You could organize your labels so that they can appear simultaneously (placing the components at 2 different BorderLayout locations will do)
panel.add(imageLabel);
panel.add(label, BorderLayout.PAGE_END);
You should make a JPanel and add it to the frame, and then add the labels to the panel
Something like
private JPanel panel = new JPanel;
and then add it to the frame in your method calling
frame.add(panel);
i get an error of Exception in thread "main" java.lang.IllegalArgumentException: illegal component position. It works when i do frame.add(label, JFrame.CENTER) but when i change it
it dosnt work.
package com.java;
import javax.swing.*;
import sun.audio.*;
import java.awt.*;
public class PlayClip extends JFrame{
public static void frame(){
JFrame frame = new JFrame("COLLIN");
frame.setSize(1086, 1200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ImageIcon image = new ImageIcon("C:MYFILE");
JLabel label = new JLabel(image);frame.setResizable(false);
frame.add(label, JLabel.BOTTOM);
frame.setVisible(true);
}
public static void main(String[] args){
frame();
}
}
You're using frame.add(label, JLabel.BOTTOM); wrong. The documentation says:
comp - the component to be added
index - the position at which to insert the component, or -1 to append the component to the end
JFrame.CENTER equals 0, by coincidence. That's why it works. TOP and BOTTOM are 1 and 3, respectively. When you use those, it's like getting an index out of bounds error on an array/list.
You should look into using a layout manager because this method isn't for what you think it's for.
This proof of concept probably does what you want:
public static void main(String[] args) {
JFrame frame = new JFrame("COLLIN");
frame.setSize(1086, 1200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel label = new JLabel("my text", SwingConstants.CENTER);
frame.setResizable(false);
frame.add(label);
frame.setVisible(true);
}
In line frame.add(label, JLabel.BOTTOM); you are assigning an alignment option for frame, not for JLabel. So you should use the constants from JFrame, and not JLabel.
The constants of JLabel are used to align the text inside the label.
Use frame.add(label). That should be enough.