Frame JButton,ContentPane - java

i have a problem of my code because all i wanna do is to appear the textfield and in the bottom the button so i used:
setLayout(new FlowLayout()); but i got an error so i decided to change into getContenPane(); but only one will appear in my frame here is my code .
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Awe extends JFrame implements ActionListener {
JTextField c;
JButton b;
Container cont = getContentPane();
public Awe() {
c = new JTextField(15);
b = new JButton("Ok");
c.addActionListener(this);
cont.add(c);
b.addActionListener(this);
cont.add(b);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (source == c) {
}
}
public static void main(String[] args) {
Awe frm = new Awe();
frm.setTitle("Enter Your Character");
frm.setSize(300, 150);
frm.setVisible(true);
}
}

You are only getting one component in your frame because its default layout is BorderLayout, and its default position is CENTER, and you can only put one component in the center.
Add the text field with cont.add(c, BorderLayout.CENTER);, and add the button with cont.add(b, BorderLayout.SOUTH);, and that should solve the immediate problem.
We can't help you with errors unless you tell us what they are, preferably with a stack trace and the code that produced them.

You need to set a layout for your frame, so the components can be arranjed, instead of being positioned on top of each other.
In your constructor add, for example:
setLayout(new FlowLayout());
And most important, read: http://docs.oracle.com/javase/tutorial/uiswing/layout/visual.html
Fully compilable, no errors:
public class Awe extends JFrame implements ActionListener {
JTextField c;
JButton b;
Container cont = getContentPane();
public Awe() {
setLayout(new FlowLayout());
c = new JTextField(15);
b = new JButton("Ok");
c.addActionListener(this);
cont.add(c);
b.addActionListener(this);
cont.add(b);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (source == c) {
}
}
public static void main(String[] args) {
Awe frm = new Awe();
frm.setTitle("Enter Your Character");
frm.setSize(300, 150);
frm.setVisible(true);
}
}

As #rcook answer, your default layout is BorderLayout which set's all components to CENTER.
Following are the ways you can do it:
Make a JPanel, add your components to JPanel then add JPanel to cont as:
JPanel panel=new JPanel();
panel.add(c);
panel.add(b);
cont.add(panel);
OR you can just use a FLOWLAYOUT as:
setLayout(new FlowLayout());
set this before adding any component to cont.
OR you can just position your components in BorderLayout as:
cont.add(c,BorderLayout.CENTER);
cont.add(b,BorderLayout.SOUTH);
Useful Links
BorderLayout
FlowLayout

the best way i always do is to use setBounds() methods
import java.awt.Dimension;
import javax.swing.*;
public class Frame extends JFrame{
JButton okBtn = new JButton ("OK");
JTextField filed = new JTextField();
public Frame(){
super.setSize(new Dimension(200,200));
super.setVisible(true);
super.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
super.setResizable(false);
super.setLayout(null);
super.getContentPane().add(okBtn);
super.getContentPane().add(filed);
filed.setBounds(10, 10, 150, 30);
okBtn.setBounds(10, 45, 70, 30);
super.validate();
}
public static void main(String[] args) {
new Frame();
}
}
and this the result

Related

How can I properly adjust the size and location of a button in JFrame?

I am attempting to make a PC Application using Java and JFrame. I'm trying to format 2 transparent buttons, each sized half of the full screen shown (vertically). The top half of the screen will hold to option to debate someone and the bottom half of the screen will hold the option to spectate a debate if clicked on. Here is what I have so far:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class BackgroundImageJFrame extends JFrame {
JButton b1;
JButton b2;
JPanel j1;
JPanel j2;
public BackgroundImageJFrame() {
setTitle("Background Color for JFrame");
setSize(340,563);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
setLayout(null);
/*
One way
-----------------
setLayout(new BorderLayout());
JLabel background=new JLabel(new ImageIcon("C:\\Users\\Computer\\Downloads\\colorful design.png"));
add(background);
background.setLayout(new FlowLayout());
l1=new JLabel("Here is a button");
b1=new JButton("I am a button");
background.add(l1);
background.add(b1);
*/
// Another way
setLayout(new BorderLayout());
setContentPane(new JLabel(new ImageIcon("C:\\Users\\MLH-User\\Downloads\\Front.jpg")));
setLayout(new FlowLayout());
j1 = new JPanel();
j1.setLayout(null);
b1 = new JButton("Spectate");
//b1.setBounds(0,0,50,50);
b1.setOpaque(false);
b1.setContentAreaFilled(false);
b1.setBorderPainted(false);
j1.add(b1);
b2 = new JButton("Debate");
b2.setLocation(0,0);
b2.setOpaque(false);
b2.setContentAreaFilled(false);
b2.setBorderPainted(false);
j1.add(b2);
add(j1);
// Just for refresh :) Not optional!
setSize(339,562);
setSize(340,563);
}
public static void main(String args[]) {
new BackgroundImageJFrame();
}
}
This is some stuff I experimented with so far, can anyone help me out about where I went wrong?
You should use a layout manager. Here is an example with GridLayout:
public class Example extends JFrame {
private static final int SIZE = 300;
public Example() {
setLayout(new GridLayout(2, 1, 0, 5));
getContentPane().setBackground(Color.WHITE);
JButton debate = new JButton("DEBATE") {
public Dimension getPreferredSize() {
return new Dimension(SIZE, SIZE);
}
};
Font font = debate.getFont().deriveFont(30f);
debate.setFont(font);
// debate.setBorderPainted(false);
debate.setBackground(Color.BLUE.brighter());
debate.setForeground(Color.WHITE);
JButton spectate = new JButton("SPECTATE") {
public Dimension getPreferredSize() {
return new Dimension(SIZE, SIZE);
}
};
spectate.setFont(font);
// spectate.setBorderPainted(false);
spectate.setBackground(Color.RED.brighter());
spectate.setForeground(Color.WHITE);
add(debate);
add(spectate);
setDefaultCloseOperation(EXIT_ON_CLOSE);
pack();
setVisible(true);
}
public static void main(final String[] args) {
SwingUtilities.invokeLater(() -> new Example());
}
}
Notes:
You have to realize that screen sizes vary. Setting SIZE to 300 was an arbitrary choice for presentation, screens might not have the required size. You can also set the insets or an empty border instead of specifying the size of the component directly.
You can consider creating a class for these buttons if you have more of them.
This is an example of setting the sizes. I don't know about the location part though.
JFrame frame = new JFrame("test");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel panel = new JPanel(new GridLayout(4,4,4,4));
for(int i=0 ; i<16 ; i++){
JButton btn = new JButton(String.valueOf(i));
btn.setPreferredSize(new Dimension(40, 40));
panel.add(btn);
}
frame.setContentPane(panel);
frame.pack();
frame.setVisible(true);

change JLabel of a panel depending on Jbutton of another panel in the same Jframe

I have constructed a class for the JPanel with several JButtons.Inside this class I want to construct another JPanel with JLabels that will change depending on the actionPerformed on the JButtons of the first JPanel.Finally, I want to add these 2 panels on the same Jframe. Can all these be done within the class of the first Panel?Otherwise, which is a better approach for this problem?
Yes, you can. One way you could accomplish this is with anonymous inner classes (saves keystrokes):
import java.awt.BorderLayout;
import java.awt.event.*;
import javax.swing.*;
public class Foo {
JLabel one;
JLabel two;
public static void main(String[] args) {
(new Foo()).go();
}
public void go() {
JFrame frame = new JFrame("Test");
// Panel with buttons
JPanel buttonPanel = new JPanel();
JButton changeOne = new JButton("Change One");
changeOne.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
one.setText("New text for one");
}
}
buttonPanel.add(changeOne);
JButton changeTwo = new JButton("Change Two");
changeTwo.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
two.setText("New text for two");
}
}
buttonPanel.add(changeTwo);
frame.add(buttonPanel, BorderLayout.NORTH);
// Panel with labels
JPanel labelPanel = new JLabel();
one = new JLabel("One");
labelPanel.add(one);
two = new JLabel("Two");
labelPanel.add(two);
// Set up the frame
frame.add(labelPanel, BorderLayout.SOUTH);
frame.setBounds(50, 50, 500, 500);
frame.setDefaultCloseAction(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}

How to set Jbuttons to a specific place when you have a background in JLabel : code below

How to set Jbuttons to a specific place when you have a background in JLabel : code below
i can't get the jlabel to stay at the top and the buttons to stay south(bottom) ??
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ButtonsClass extends JFrame
implements ActionListener {
JButton b1 = new JButton("button1");
JButton b2 = new JButton("button2");
JButton b3 = new JButton("button3");
JButton b4 = new JButton("button4");
JLabel label = new JLabel("buttons:");
public static void main(String[] args) {
new ButtonsClass();
}
public Jukebox() {
setLayout(new BorderLayout());
setContentPane(new JLabel(new ImageIcon("image.png")));
setLayout(new FlowLayout());
setSize(500,150);
setTitle("Backgroundwithbuttons");
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
JPanel top = new JPanel();
top.add(label);
add("North", top);
JPanel bottom = new JPanel();
bottom.add(b1);
bottom.add(b2);
bottom.add(b3);
bottom.add(b4);
add("South", bottom);
setVisible(true);
}
}
" i can't get the jlabel to stay at the top and the buttons to stay south(bottom)"
That's because you set the layout the BorderLayout, then immediately set it to FlowLayout. With FlowLayout, your BorderLayout positioning will do nothing.
setLayout(new BorderLayout());
setContentPane(new JLabel(new ImageIcon("image.png")));
setLayout(new FlowLayout());
Just get rid of the setLayout(new FlowLayout());
Also your constructor is wrong
public Jukebox() {
-Should be-
public ButtonClass() {
Also you need to set the layout of the JLabel that you set as the content pane. Yout constructor should look like this
public ButtonClass() {
JLabel background = new JLabel(new ImageIcon("image.png"));
background.setLayout(new BorderLayout());
setContentPane(background);
setTitle("Background with buttons");
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
JPanel top = new JPanel();
top.add(label);
add(top, BorderLayout.NORTH);
JPanel bottom = new JPanel();
bottom.add(b1);
bottom.add(b2);
bottom.add(b3);
bottom.add(b4);
add(bottom, BorderLayout.SOUTH);
//pack();
setVisible(true);
}
Also, add("North", top); is a deprecated method. Instead use add(top, BorderLayout.NORTH) and same for add(bottom, BorderLayout.SOUTH)
Also, Swing apps should be run on the Event Dispatch Thread. You can do so by wrapping the code in your main with a SwingUtilities.invokeLater...
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ButtonClass();
}
});
}
Also, you should set the panel's opaque property to false, if you want the image to show behind them.
top.setOpaque(false);
bottom.setOpaque(false);
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ButtonClass extends JFrame
implements ActionListener {
JButton b1 = new JButton("button1");
JButton b2 = new JButton("button2");
JButton b3 = new JButton("button3");
JButton b4 = new JButton("button4");
JLabel label = new JLabel("buttons:");
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new ButtonClass();
}
});
}
public ButtonClass() {
label.setForeground(Color.WHITE);
JLabel background = new JLabel(new ImageIcon(getClass().getResource("/resources/space.png")));
background.setLayout(new BorderLayout());
setContentPane(background);
setTitle("Background with buttons");
setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
JPanel top = new JPanel();
top.setOpaque(false);
top.add(label);
add(top, BorderLayout.NORTH);
JPanel bottom = new JPanel();
bottom.setOpaque(false);
bottom.add(b1);
bottom.add(b2);
bottom.add(b3);
bottom.add(b4);
add(bottom, BorderLayout.SOUTH);
setSize(400, 300);
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {}
}
Try using:
add(bottom, BorderLayout.SOUTH);
instead of:
add("South", bottom);
BorderLayout tutorial

Java Swing Removing Jpanel while clicking on Jbutton which is present in that jpanel which I want to remove

I am creating a GUI using Netbeans and my question is "how to remove the jpanel"...the hierarchical order as it is present Jframe->Jscrollpane->Jpanel->Jbutton. By clicking on the Jbutton I want to remove all components of the jpanel including the Jbutton(on which I am clicking) and the panel itself. Please do help.Urgent.THanks in advance
-Sayantan
private void b4ActionPerformed(java.awt.event.ActionEvent evt) {
final JPanel jp;
JTextField tf,of1,of2,xf,yf;
int i=1;
int m=(int)sp3.getValue();
JButton jb;
jp=new JPanel();
//jp.setLayout(new GridBagLayout());
DesignGridLayout layout = new DesignGridLayout(jp);
jsp2.getViewport().add(jp);
while(i<=m){
tf=new JTextField(5);
of1=new JTextField(5);
of2=new JTextField(5);
layout.row().grid(new JLabel("Type:")).indent(9).add(tf).grid(new JLabel("Length:")).indent().add(of1).grid(new JLabel("Breadth:")).indent().add(of2).empty();
fields1.add(tf);
fields1.add(of1);
fields1.add(of2);
xf=new JTextField(5);
yf=new JTextField(5);
layout.row().grid(new JLabel("X-axis:")).indent(9).add(xf).grid(new JLabel("Y-axis:")).indent().add(yf).empty(2);
fields1.add(xf);
fields1.add(yf);
i++;
}
jb=new JButton("Submit");
jb.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
for(JTextField field: fields1){
String s=field.getText();
lbr.setText(lbr.getText()+s);
}
lb3.setVisible(false);
sp3.setVisible(false);
b4.setVisible(false);
//jp.setVisible(false);
//jp.removeAll();
// jp.revalidate();
//jp.repaint();
// jsp2.remove(jp);
//jsp2.revalidate();
//jsp2.repaint();
}
});
layout.emptyRow();
layout.row().right().add(jb);
jp.revalidate();
jp.repaint();
// jsp2.revalidate();
//jsp2.repaint();
}
Note: I am using DesignGridLayout package.
This works:
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class ScratchSpace {
public static void main(String[] args) {
final JPanel panel = new JPanel();
panel.setOpaque(true);
panel.setBackground(Color.YELLOW);
panel.add(new JButton(new AbstractAction("Kill me") {
#Override
public void actionPerformed(ActionEvent e) {
panel.removeAll();
panel.revalidate();
panel.repaint();
}
}));
final JFrame frame = new JFrame();
frame.setContentPane(panel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
I want to remove all components of the jpanel including the Jbutton(on which I am clicking) and the panel itself.
Then you need code something like:
JButton button = (JButtton)event.getSource();
JPanel grandparent = button.getParent().getParent();
grandparent.removeAll();
grandparent.revalidate();
grandparent.repaint();
Although I question any code where I see a removeAll(). You might look into using a Card Layout.

JScrollPane won't work

Hey guys I wanted to create a JScrollPane but it won't work... and I don't know why... here's my code...
public class test extends JFrame{
public test(){
setSize(1000,600);
}
private static JButton[] remove;
private static JPanel p = new JPanel();
public static void main(String[]args){
p.setLayout(null);
JFrame t=new test();
remove = new JButton[25];
for(int i=0;i<25;i++){
remove[i]=new JButton("Remove");
remove[i].setBounds(243,92+35*i,85,25);
p.add(remove[i]);
}
JScrollPane scrollPane = new JScrollPane(p);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
t.add(scrollPane);
t.setVisible(true);
}
Umm and Im pretty sure the frame isn't big enough for these 25 buttons... But if i delete that p.setLayout(null); A horizontal scroll bar will be created automatically... I don't really know what is wrong with my code... Pls help thank you very much!
You need to set p's preferredSize for this to work.
p.setPreferredSize(new Dimension(800, 2000));
Or you could have p extend JPanel and then override the getPreferredSize() method to return the proper dimension.
And I agree -- get rid of your null layouts. Learn about and use the layout managers if you want to use Swing correctly and have robust Swing GUI's.
e.g.,
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Foo extends JFrame {
private static final int BUTTON_COUNT = 25;
public static void main(String[] args) {
JPanel btnPanel = new JPanel(new GridLayout(0, 1, 0, 20));
btnPanel.setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
AbstractAction removeAction = new AbstractAction("Remove") {
#Override
public void actionPerformed(ActionEvent evt) {
JButton src = (JButton) evt.getSource();
JPanel container = (JPanel) src.getParent();
container.remove(src);
container.revalidate();
container.repaint();
}
};
for (int i = 0; i < BUTTON_COUNT; i++) {
JButton removeBtn = new JButton(removeAction);
btnPanel.add(removeBtn);
}
JPanel borderPanel = new JPanel(new BorderLayout());
borderPanel.add(btnPanel, BorderLayout.NORTH);
JScrollPane scrollpane = new JScrollPane(borderPanel,
JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
scrollpane.setPreferredSize(new Dimension(400, 800));
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(scrollpane);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
The issue is that a scroll pane checks the component inside it for a "preferred size" so a pane with a null layout has a preferred size of (0,0). Which it ignores.
You should do something along the lines of:
p.setPreferredSize(1000,600);
And you should see some scroll bars appear, I'm not sure how accurate they will be though.

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