I'm looking for a way to set the display of a JTextField to take up the entire width of the JPanel that contains it.
The only method I've been able to find to do this is the setColumns() method combined with a getWidth() method called on the JPanel after the pack() and setVisible() methods are called. But when I do this the JTextField ends up much larger than the JPanel that encloses it. My assumption on why this happens is that the getWidth() returns that size of the JPanel in pixels, and the columns in the JTextField are all larger than a pixel.
I'm not even looking for the field to dynamically resize, just to be as wide as the JPanel at the start of the program
Any help greatly appreciated
Make use of an appropriate layout manager...
Remember, it's not the responsibility of the component to decide how big it should, that's the responsibility of the layout manager, the component can only provide hints about how big it would like to be...
For example, you could do this with a GridBagLayout...
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
JTextField field = new JTextField(10);
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.weightx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
add(field, gbc);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
}
Take a look at Laying Out Components Within a Container for more details
Related
With all the different 'containers' I'm using, it's hard to set my window size in the code. I guess I need them but at the same time need to find a way to change settings around it.
I've tried doing frame.setSize(int x, int y), did not work.
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TweetProgram1{
public static void main(String[] args) {
new TweetProgram1();
}
public TweetProgram1() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Tweet Program");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TweetProgram1Pane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TweetProgram1Pane extends JPanel {
public TweetProgram1Pane() {
setLayout(new GridBagLayout());
JLabel lbl = new JLabel("Random tweet");
JButton btn = new JButton("Send it");
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = 300;
gbc.gridheight = 300;
add(lbl, gbc);
add(btn, gbc);
}
}
}
I expect to be able to re-scale the window size (in the code) to whatever I need it to be.
Thanks
I want split my Frame into two JPanel and the right JPanel serve as a textarea used to input and display.
However, I can't input anything in it and it can't display any thing.
the code as below:
JPanel jp1, jp2;
public DemoFrame() {
jp1 = new JPanel();
jp2 = new JPanel();
JLabel label = new JLabel("text");
JTextArea ta = new JTextArea(100,100);
ta.setText("some text");
ta.setSize(300, 300);
jp2.add(label);
jp2.add(ta);
JSplitPane jsp = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, jp1, jp2);
this.getContentPane().add(jsp);;
setBounds(300, 200, 500, 500);
setVisible(true);
jsp.setDividerLocation(0.5);//
}
the output as below(it doesnt display anything):
Congratulations, you've fallen victim to a number of conspiring issues.
The main culprit is FlowLayout, which is the default layout manager for JPanel. Essentially, when you add your, rather large, JTextArea to the panel, the FlowLayout is trying to honour the preferred size as best as it can within the constraints of the available space. For reasons I'm not 100% sure of, that means laying out the component beyond the visible bounds of the container.
If you type enough text, you will begin to see it.
While there are a number of ways you might fix this, they are basically the same solution - use a different layout manager.
For this example, I've just used a BorderLayout instead
import java.awt.BorderLayout;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
private JPanel jp1, jp2;
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
jp1 = new JPanel();
jp2 = new JPanel(new BorderLayout());
JLabel label = new JLabel("text");
JTextArea ta = new JTextArea(50, 50);
ta.setText("some text");
jp2.add(label, BorderLayout.NORTH);
jp2.add(new JScrollPane(ta));
JSplitPane jsp = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, jp1, jp2);
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(jsp);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
I have tried multiple solutions but nothing fits me!
I want to align everything vertically on the center of the frame.
window=new JFrame();
window.setSize(520, 380);
window.setTitle("Menu");
window.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
window.setLayout(new FlowLayout());
label=new JLabel("Settings",JLabel.CENTER);
controlPanel= new JPanel();
controlPanel.setLayout(new GridLayout(10,1));
controlPanel.add(button1);//these are example components
controlPanel.add(button2);
controlPanel.add(button3);
window.add(label);
window.add(controlPanel);
window.setVisible(true);
I want to have as a title the word "Settings" and exactly underneath it my components.
I was able to do this with a gridLayout instead of FlowLayout but the title occupies half of the screen(and i dont want that).
sorry for a basic question like that but i am new to java :)
You could use GridBagLayout, for example...
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;
public class TestLayout {
public static void main(String[] args) {
new TestLayout();
}
public TestLayout() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setBorder(new EmptyBorder(50, 50, 50, 50));
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
gbc.fill = GridBagConstraints.HORIZONTAL;
add(new JButton("Apples"), gbc);
add(new JButton("Pears"), gbc);
add(new JButton("Organges"), gbc);
add(new JButton("Grapes"), gbc);
}
}
}
Remember, with it's flexibility, comes complexity. Have a look at How to Use GridBagLayout for more details
Let's say a JFrame contains just 1 JPanel. This JPanel is divided into 2 JPanels occupying accordingly 0.75 and 0.25 of the JFrame height. I want all of this to be resizable along with the window size.
I have no idea how to do this in Java.
I'm a newbie to Java. I've read a bit about layouts, but all I can see is how to set preferred size in constructor (ceasing to resize when this number is reached) or some fixed sizes obtained through setting borders.
JFrame with a BorderLayout, onto that, add a JPanel with a GridBagLayout. Add your other two panels onto this.
See Laying Out Components Within a Container and How to Use GridBagLayout for more details
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.fill = GridBagConstraints.BOTH;
gbc.weightx = 1;
gbc.weighty = 0.75;
JPanel top = new JPanel(new GridBagLayout());
top.add(new JLabel("Top"));
top.setBackground(Color.RED);
add(top, gbc);
gbc.gridy++;
gbc.weighty = 0.25;
JPanel bottom = new JPanel(new GridBagLayout());
bottom.add(new JLabel("Bottom"));
bottom.setBackground(Color.BLUE);
add(bottom, gbc);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
}
i am trying to set size of JButton, but by default it take whole frame, it's height easily set but i can't set it's width & why its behaving like that i don't know.
my code :
JButton btnNewButton = new JButton("");
btnNewButton.setPreferredSize(new Dimension(32,0));
ImageIcon icon = new ImageIcon(this.getClass().getResource("/images/images_Left.png"));
btnNewButton.setIcon(icon);
boxTlacitek.add(btnNewButton);
getContentPane().add(btnNewButton, BorderLayout.NORTH);
any suggestion please ?
Change the layout. Try adding the button to another JPanel then add the panel the frame. BorderLayout will stretch the button across the available width of the panel when the component is placed in the NORTH or SOUTH position
import java.awt.BorderLayout;
import java.awt.EventQueue;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestBorderLayout {
public static void main(String[] args) {
new TestBorderLayout();
}
public TestBorderLayout() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JButton fat = new JButton("Fat");
JButton skinny = new JButton("Skinny");
JPanel buttonPane = new JPanel();
buttonPane.add(skinny);
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(fat, BorderLayout.NORTH);
frame.add(buttonPane, BorderLayout.SOUTH);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
getContentPane().setLayout(null);
//setBounds(x,y,width,height)
btnNewButton.setBounds(10,10,250,100);
getContentPane().add(btnNewButton);