How to use setBounds method for a JLabel? - java

I'm making a window application with Swing. I am using the setBounds() method for the JLabel spacing but it's not working.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class FullScreenJFrame extends JFrame
{
public FullScreenJFrame( String title )
{
super(title);
//JFrame frame = new JFrame();
this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
setUndecorated(true);
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds(0,0,screenSize.width, screenSize.height);
getContentPane()
.add(new JLabel(" HIGHCOURT OF JUDICATURE AT ALLHAHABAD"), BorderLayout.NORTH);
JLabel label = new JLabel("JJ");
label.setBounds(20, 20, 150, 20);
// label.setText(s);
add(label);
}
public static void main( String[] args )
{
FullScreenJFrame frame = new FullScreenJFrame("");
//JFrame frame1 = new JFrame();
//JLabel label = new JLabel("dd");
//label.setBounds(370, 340, 150, 20);
//frame1.add(label);
frame.setVisible(true);
}
}

One advice, It seems you are going to show your application using all screen so try to avoid the use of absolute positions like setBoundMethod.
You should fit your application within a layout that uses other layouts within it. Check this link.
http://docs.oracle.com/javase/tutorial/uiswing/layout/visual.html

Don't use setBounds() to resize a component. Use a Layout Manager and you won't be worried about manually doing this.

Why?
Why are going for absolute positioning, when Layout Managers do it for you.
One more thing, If your JFrame does not contain any title so there is no need to add empty title as it is bad practice.
Replace
FullScreenJFrame frame = new FullScreenJFrame("");
By
FullScreenJFrame frame = new FullScreenJFrame();
And
public FullScreenJFrame( String title )
By
public FullScreenJFrame()
No need to call
super(title);

Or in order to set your layout as null right click on your form and click set layout then click null layout.

Are null layouts recommended? As other have suggested, the answer is NO.
See Laying out Components in a Container to get some practice in with LayoutManagers
Will I still answer your question? Sure. Just so you know.
"I am using the setBounds() method for the JLabel spacing but it's not working. Please, can any one tell me why it is not working?"
Yes, your bounds aren't working because the JFrame has a default Borderlayout. In order for setBounds to work, the layout needs to be null.
setLayout(null);
Also, keep in mind that when you do use a null layout, any components in which you don't setBounds for will not appear.
See Laying out Components in a Container to get some practice in with LayoutManagers

Related

Java cannot display the JPanel, but can display JLabel?

The question is that I cannot add JPanel and JLabel in the Frame at the same time.
When i using following code, only MyPanel will be visible. myFrame.add(myLabel);myFrame.add(myPanel);myFrame.setVisible(true);
when I execute: myFrame.add(myLabel);myFrame.setVisible(true);myFrame.add(myPanel);
only myLabel will be visible.
import javax.swing.*;
import java.awt.*;
public class Main {
public static void main(String[] args) {
MyFrame myFrame = new MyFrame();
MyLabel myLabel = new MyLabel();
MyPanel myPanel = new MyPanel();
myFrame.add(myLabel);
myFrame.add(myPanel);
myFrame.setVisible(true);
}
}
public class MyFrame extends JFrame {
MyFrame() {
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //exit out of application.
//https://docs.oracle.com/javase/7/docs/api/javax/swing/JFrame.html#setDefaultCloseOperation%28int%29
this.setSize(750, 750); //set the size.
this.setResizable(true);//resize the frame.
this.setTitle("Welocme to new world."); //set the Title.
ImageIcon imageIcon = new ImageIcon("logo.png");
this.setIconImage(imageIcon.getImage());
this.getContentPane().setBackground(new Color(217, 217, 217));
this.setBackground(Color.YELLOW);//this.setVisible(true);//Make the frame visible.
}}
import javax.swing.*;
import java.awt.*;
public class MyPanel extends JPanel {
MyPanel() {
this.setBackground(Color.white);
this.setBounds(2,2,25,25);
}}
import javax.swing.*;
import java.awt.*;
public class MyLabel extends JLabel {
MyLabel(){
this.setText("<html>Heaven <br/>Heaven's body\"<br/> Whirl around me <br/>Make me wonder</html>");
//,SwingConstants.CENTER);
//https://stackoverflow.com/questions/1090098/newline-in-jlabel
//How to print multi line in java
ImageIcon image = new ImageIcon("Cosmogony_Björk_Cover.jpg");
this.setIcon(image);
//jLabel.setForeground(new Color(217,217,217));
this.setForeground(Color.BLACK);
this.setFont(new Font("helvetica",Font.PLAIN,18));
this.setBackground(Color.gray);
this.setOpaque(true);
//jLabel.setVerticalTextPosition(JLabel.TOP); Set the relative text position of the label.
//jLabel.setBorder();
this.setVerticalAlignment(JLabel.CENTER);
this.setHorizontalAlignment(JLabel.CENTER);
}}
The default Layout Manager of JFrame is the BorderLayout.
Since you did not change the layout manager of your JFrame this is also the current layout manager used in your snippet.
Usually, when using the BorderLayout, you specify which area of the BorderLayout should be populated when adding a component. This is usually done via
frame.add(component, BorderLayout.CENTER);
Notice the area specification in the add() method, which tells the BorderLayout where to place the component.
Here is the issue however. If you use the add() method in combination with the BorderLayout without specifying the placement of the component, it will always place the component in BorderLayout.CENTER. (Causing the component which is currently there to be replaced)
To work around this, do one of the following things:
Specify the placement explicitly, so both components will show up:
frame.add(component1, BorderLayout.PAGE_START);
frame.add(component2, BorderLayout.CENTER);
Or use a different Layout Manager, which will take care of the placement for you. E.g. FlowLayout
JPanel contentPanel = new JPanel(); // JPanel uses flowlayout by default!
contentPanel.add(component1);
contentPanel.add(component2);
myFrame.setContentPane(contentPanel);
You could also explicitly set the layout:
Container contentPane = myFrame.getContentPane();
// creates new FlowLayout and sets on content pane
contentPane.setLayout(new FlowLayout());
contentPane.add(component1);
contentPane.add(component2);
Sidenotes:
Look through the Laying out components within a container Oracle tutorial, which will give you more information on which layout managers there are and how to work with them.
When building your GUI, setVisible() on the JFrame should be the last thing you are doing after adding all components. Because if you add components after setting the frame visible, the changes will not immediately take effect without you telling swing that something changed.
When correctly working with the Swing Layout Managers, there should be no need to use things like setBounds(...) or setSize(). After adding all components, calling pack() on the JFrame is the preferred way to go. This will size the JFrame according to the preferred size of the components inside.

Can not display the features using JFrame [duplicate]

I'm fairly new to JFrame and I want to know why my items are not showing up on the window. I know i dont have a ActionHandler but I just want my textfield's to show up on my window. Here's my code:
import java.awt.Font;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
public class FirstGUI extends JFrame{
public void GUI(){
setTitle("Welcome");
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
setSize(600,600);
JLabel title = new JLabel();
title.setText("Apple Inc. Member Login Port");
title.setFont(new Font("Arial", Font.PLAIN, 24));
JTextField login = new JTextField("Login",10);
JPasswordField pass = new JPasswordField("Password");
add(title);
add(login);
add(pass);
}
public static void main(String[] args){
FirstGUI a = new FirstGUI();
a.GUI();
}
}
but when i run it i get this:
but when i run it i get this:
You get an empty screen because you add the components to the frame after the frame is visible.
As has already been suggested you need to use an appropriate layout manager. FlowLayout is the easiest to start with.
invoke setVisible(true) AFTER adding the components to the frame.
So the code should be more like:
panel.add(...);
panel.add(...);
add(panel);
pack();
setVisible(true);
I agree to MadProgrammer's suggestions (+1)
Well, lets take a look at your program though
You actually have created a JFrame with components in it. Its working fine as well, but your question of "why are my items not showing up in the JFrame" is not because you did something wrong but because missed out something i.e. revalidate()
Try:
public static void main(String[] args){
FirstGUI a = new FirstGUI();
a.GUI();
a.revalidate();
}
I'm not saying this will give you perfect UI.. what I'm trying to say is this will help you understand the Swing better. Learn about Swing Layout managers and then work on your UI to have better results
revalidate(): This component and all parents above it are marked as needing to be laid out. This means the Layout Manager will try to realign the components. Often used after removing components. It is possible that some really sharp swing people may miss this. I would think that you will only know this if you are actually using Swing.
The default layout manager for JFrame is BorderLayout.
This means that your components are essentially all been added ontop of each other.
Try changing the layout manager to something like FlowLayout (for example)...
Take a look at A Visual Guide to Layout Managers and Using Layout Managers for more details.
Also, avoid setSize where possible, use Window#pack instead
Update
I'd also like to introduce you to Initial Threads which should be used to launch your UI code...
The only one reason :
setVisible(True); method for the frame should be put on the end of the code.
if you give this line on the top of the code that is when you create a frame. This will cause that problem.
Don't add the components directly to your frame. Instead add to the content pane, which is where a JFrame stores all of the components that it draws. Usually this is a JPanel.
Here is an example:
public class GUI
{
private JPanel content;
public void GUI
{
/*Other code*/
content = new JPanel();
add(content); //make content the content pane
content.add(title);
content.add(login);
content.add(pass);
}
If that fails, call setVisible(true) and setEnabled(true) on all of your components.
On a side note you may want to make your GUI function a constructor.
import javax.swing.*;
import java.awt.*;
class Myframec extends JFrame
{
Myframec()
{
Container c = this.getContentPane();
c.setLayout(null);
this.setBounds(10,10,700,500);
this.setTitle("Welcome");
this.setDefaultCloseOperation(this.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setBounds(0,0,700,500);
panel.setBackground(Color.gray);
panel.setLayout(null);
c.add(panel);
Font f = new Font("Arial",Font.BOLD,25);
Font f1 = new Font("Arial",Font.BOLD,20);
JLabel lable = new JLabel();
lable.setBounds(130,10,400,100);
lable.setText("Apple Inc. Member Login Port");
lable.setFont(f);
panel.add(lable);
JTextField login = new JTextField("Login",10);
login.setBounds(120,150,400,30);
login.setFont(f1);
panel.add(login);
JPasswordField pass =new JPasswordField("Password");
pass.setBounds(120,200,400,30);
pass.setFont(f1);
lable.setFont(f);
panel.add(pass);
c.setVisible(true);
this.setVisible(true);
}
public static void main(String[] argm)
{
Myframec frame = new Myframec();
frame.setVisible(true);
}
}

JFrame Image wont appear, require refresh? [duplicate]

I'm fairly new to JFrame and I want to know why my items are not showing up on the window. I know i dont have a ActionHandler but I just want my textfield's to show up on my window. Here's my code:
import java.awt.Font;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
public class FirstGUI extends JFrame{
public void GUI(){
setTitle("Welcome");
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
setSize(600,600);
JLabel title = new JLabel();
title.setText("Apple Inc. Member Login Port");
title.setFont(new Font("Arial", Font.PLAIN, 24));
JTextField login = new JTextField("Login",10);
JPasswordField pass = new JPasswordField("Password");
add(title);
add(login);
add(pass);
}
public static void main(String[] args){
FirstGUI a = new FirstGUI();
a.GUI();
}
}
but when i run it i get this:
but when i run it i get this:
You get an empty screen because you add the components to the frame after the frame is visible.
As has already been suggested you need to use an appropriate layout manager. FlowLayout is the easiest to start with.
invoke setVisible(true) AFTER adding the components to the frame.
So the code should be more like:
panel.add(...);
panel.add(...);
add(panel);
pack();
setVisible(true);
I agree to MadProgrammer's suggestions (+1)
Well, lets take a look at your program though
You actually have created a JFrame with components in it. Its working fine as well, but your question of "why are my items not showing up in the JFrame" is not because you did something wrong but because missed out something i.e. revalidate()
Try:
public static void main(String[] args){
FirstGUI a = new FirstGUI();
a.GUI();
a.revalidate();
}
I'm not saying this will give you perfect UI.. what I'm trying to say is this will help you understand the Swing better. Learn about Swing Layout managers and then work on your UI to have better results
revalidate(): This component and all parents above it are marked as needing to be laid out. This means the Layout Manager will try to realign the components. Often used after removing components. It is possible that some really sharp swing people may miss this. I would think that you will only know this if you are actually using Swing.
The default layout manager for JFrame is BorderLayout.
This means that your components are essentially all been added ontop of each other.
Try changing the layout manager to something like FlowLayout (for example)...
Take a look at A Visual Guide to Layout Managers and Using Layout Managers for more details.
Also, avoid setSize where possible, use Window#pack instead
Update
I'd also like to introduce you to Initial Threads which should be used to launch your UI code...
The only one reason :
setVisible(True); method for the frame should be put on the end of the code.
if you give this line on the top of the code that is when you create a frame. This will cause that problem.
Don't add the components directly to your frame. Instead add to the content pane, which is where a JFrame stores all of the components that it draws. Usually this is a JPanel.
Here is an example:
public class GUI
{
private JPanel content;
public void GUI
{
/*Other code*/
content = new JPanel();
add(content); //make content the content pane
content.add(title);
content.add(login);
content.add(pass);
}
If that fails, call setVisible(true) and setEnabled(true) on all of your components.
On a side note you may want to make your GUI function a constructor.
import javax.swing.*;
import java.awt.*;
class Myframec extends JFrame
{
Myframec()
{
Container c = this.getContentPane();
c.setLayout(null);
this.setBounds(10,10,700,500);
this.setTitle("Welcome");
this.setDefaultCloseOperation(this.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setBounds(0,0,700,500);
panel.setBackground(Color.gray);
panel.setLayout(null);
c.add(panel);
Font f = new Font("Arial",Font.BOLD,25);
Font f1 = new Font("Arial",Font.BOLD,20);
JLabel lable = new JLabel();
lable.setBounds(130,10,400,100);
lable.setText("Apple Inc. Member Login Port");
lable.setFont(f);
panel.add(lable);
JTextField login = new JTextField("Login",10);
login.setBounds(120,150,400,30);
login.setFont(f1);
panel.add(login);
JPasswordField pass =new JPasswordField("Password");
pass.setBounds(120,200,400,30);
pass.setFont(f1);
lable.setFont(f);
panel.add(pass);
c.setVisible(true);
this.setVisible(true);
}
public static void main(String[] argm)
{
Myframec frame = new Myframec();
frame.setVisible(true);
}
}

Strange setBackground() error - Java Swing

import java.awt.*;
import javax.swing.*;
public class JFrameGUI extends JFrame
{
JLabel item1;
public JFrameGUI(int l, int b , String Title)
{
setTitle(Title);
setLayout(new FlowLayout());
setSize(l, b);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
item1 = new JLabel("This is a Sentence.");
item1.setToolTipText("This is gonna show up on hover.");
add(item1);
}
public static void main(String[] args)
{
JFrameGUI g = new JFrameGUI(1280,720,"The End Of The Line");
JPanel p = new JPanel();
p.setBackground(Color.BLUE);
g.add(p);
}
}
When I execute this , all i get is a tiny Blue square nest to the "This is a sentence" string . I've tried everything !
You need to set the layout of the frame to a layout that doesn't respect the preferred sizes of its children. FlowLayout does, and your JPanel has no preferred size without any components added to it, or specifying a preferred size.
A simple fix, set the layout of the frame to BorderLayout, or not set a layout at all, since JFrame already has a default BorderLayout. Note though that you probably want to add the JLabel to the JPanel and not the JFrame. Unless you do want to add it the JFrame and not the background JPanel, you need to specify a BorderLayout position for the one you don't want in the center.
You can see this answer to see which layout managers respect preferred sizes and which don't
See more at Layout out Components Withing a Container
Also, setVisible(true) shoul be the last thing you do after adding all components.

Java Swing - JLabel Location

I have problem while setting the Jlabel location.
I set the content pane to some JPanel, I created and tried to add my JLabel.
JLabel mainTitle = new JLabel("SomeApp");
mainTitle.setFont(new Font("Arial",2 , 28));
mainTitle.setBounds(0,0, 115, 130);
getContentPane().add(mainTitle);
I want that my JPanel will be on the top left corner on my application and what I am getting is "SomeApp" on the top center.(and not top left).
btw I tried to add JButton the and the I can`t change the width,height,x,y of the JButton.
Swing uses Layout Managers to place the components.
You have to understand how they work to use them effectively. You can set the layout manager to null, and do the layout your self, but is not recommendable because you'll have to keep track of new components each time, and perform layout computation your self when the window moves shrink etc.
Layout managers are a bit hard to grasp at first.
Your windows could be like this:
Using this code:
import javax.swing.*;
import java.awt.Font;
import java.awt.FlowLayout;
class JLabelLocation {
public static void main( String [] args ) {
JLabel mainTitle = new JLabel("SomeApp");
mainTitle.setFont(new Font("Arial",2 , 28));
//mainTitle.setBounds(0,0, 115, 130); //let the layout do the work
JFrame frame = new JFrame();
JPanel panel = new JPanel(new FlowLayout(FlowLayout.LEFT));// places at the left
panel.add( mainTitle );
frame.add( panel );// no need to call getContentPane
frame.pack();
frame.setVisible( true );
}
}
Where a particular widget ends up in its container depends on the layout manager that it's using. The layout manager determines how to resize and arrange the widgets to make them fit appropriately. Obviously, the default layout for the content pane decided that the top center was the best place to put the JLabel.
If you want to get to not use a layout manager and just place everything yourself (which generally isn't the best way to lay things out btw), then add:
getContentPane().setLayout(null);
Using layouts is usually a better idea since they allow for dynamic resizing of components. Here's how you'd do it with a BorderLayout:
this.getContentPane().setLayout(new BorderLayout());
this.getContentPane().add (new JLabel ("Main title"), BorderLayout.NORTH);
If you want to add something to the right of the label you could create an additionnal panel with it's own layout :
// Create a panel at the top for the title and anything else you might need
JPanel titlePanel = new JPanel (new BorderLayout());
titlePanel.add(new JLabel ("Main title"), BorderLayout.WEST);
// Add the title panel to the frame
this.getContentPane().setLayout(new BorderLayout());
this.getContentPane().add(titlePanel, BorderLayout.CENTER);
Here are some usefull links to get started with layouts:
http://download.oracle.com/docs/cd/E17409_01/javase/tutorial/uiswing/layout/visual.html
http://download.oracle.com/docs/cd/E17409_01/javase/tutorial/uiswing/layout/using.html

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