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);
}
});
}
}
Related
I'm currently working on a media player for java, and with the power of VLCJ I was working on implementing an equalizer adjust window. There will be 11 vertical sliders with a JLabel underneath them indicating the hZ band and the dB level of the band. However, the slider keeps adding a huge gap between itself and the JLabel. I tried stacking just two JLabels on top of each other and there's barely a gap at all. My code is below. (The return equalizer stuff hasn't been implemented yet. I just want a basic UI working before I start adding in the functionality)
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import uk.co.caprica.vlcj.player.Equalizer;
public class VideoEQFrame {
public VideoEQFrame() {
//constructor
}
public Equalizer show() {
JFrame frame = new JFrame("Effects");
JPanel panel = new JPanel();
JPanel sliders= new JPanel();
JPanel gainObjects = new JPanel(new GridLayout(2, 0, 2, 0));
JSlider gainS = new JSlider(JSlider.VERTICAL, -12, 12, 0);
gainS.setMajorTickSpacing(2);
gainS.setPaintTicks(true);
gainS.setToolTipText("Adjust the gain");
JLabel gainL = new JLabel("Text");
gainObjects.add(gainS);
gainObjects.add(gainL);
sliders.add(gainObjects);
panel.add(sliders);
frame.add(panel);
frame.setSize(new Dimension(600, 300));
//frame.setResizable(false);
frame.setVisible(true);
Equalizer eq = new Equalizer(0);
return eq;
}
}
You are using GridLayout to lay the slider and the text label. That means that they will both occupy the same height. So because the slider has bigger height, the height of the label also adjusts to this height. Try using another LayoutManager like BorderLayout, like so:
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
public class VideoEQFrame {
public VideoEQFrame() {
//constructor
}
public void show() {
JFrame frame = new JFrame("Effects");
JPanel panel = new JPanel();
JPanel sliders= new JPanel();
JPanel gainObjects = new JPanel(new BorderLayout());
JSlider gainS = new JSlider(JSlider.VERTICAL, -12, 12, 0);
gainS.setMajorTickSpacing(2);
gainS.setPaintTicks(true);
gainS.setToolTipText("Adjust the gain");
JLabel gainL = new JLabel("Text");
gainObjects.add(gainS, BorderLayout.CENTER);
gainObjects.add(gainL, BorderLayout.PAGE_END);
sliders.add(gainObjects);
panel.add(sliders);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(panel);
frame.pack();
frame.setLocationRelativeTo(null);
//frame.setResizable(false);
frame.setVisible(true);
// Equalizer eq = new Equalizer(0);
// return eq;
}
public static void main(final String[] args) {
new VideoEQFrame().show();
}
}
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
I am creating a JFrame object with some JPanels next to each other side by side.
I want the JPanels to have a 15px margin, etched border, and 15px padding. At first I thought that this would be something really intuitive just like the HTML box model, so I tried to create CompoundBorder inside a CompoundBorder but that wouldn't work.
Here's my code:
import java.awt.Dimension;
import javax.swing.*;
public class StackOverFlowExample extends JFrame {
public static void main() {
stackOverFlowExample window = new stackOverFlowExample();
window.setVisible(true);
}
public StackOverFlowExample() {
// create buttons
JButton foo = new JButton("foo");
JButton bar = new JButton("bar");
JButton foo2 = new JButton("foo2");
JButton bar2 = new JButton("bar2");
// create panels and add buttons to them
JPanel left = new JPanel();
left.setBorder(BorderFactory.createEtchedBorder());
left.setLayout(new BoxLayout(left, BoxLayout.PAGE_AXIS));
left.add(foo);
left.add(bar);
JPanel right = new JPanel();
right.setBorder(BorderFactory.createEtchedBorder());
right.setLayout(new BoxLayout(right, BoxLayout.PAGE_AXIS));
right.add(foo2);
right.add(bar2);
// add panels to frame
this.getContentPane().setLayout(new BoxLayout(
getContentPane(), BoxLayout.LINE_AXIS));
this.getContentPane().add(left);
this.getContentPane().add(right);
// finalize layout
this.setPreferredSize(new Dimension(150,150));
this.pack();
this.setVisible(true);
}
}
I'm aware that I could have just used GridBagConstraints or JButton.setMargin() to create the padding, and then use CompoundBorder to create the etched border with an empty border. What if I don't want to make my code look messy with those techniques though?
I'm not sure what problems you might be having, as you've not supplied an example of what you've tried, but the basic process would be to...
Create the inner border requirements (EtchedBorder wrapping a EmptyBorder), for example, new CompoundBorder(emptyBorder, etchedBorder)
Create the outer border requirements (EmptyBorder wrapping the inner compound border), for example, new CompoundBorder(inner, emptyBorder);
Apply this outer border to the component...
As an example...
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
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.CompoundBorder;
import javax.swing.border.EmptyBorder;
import javax.swing.border.EtchedBorder;
public class Test1 {
public static void main(String[] args) {
new Test1();
}
public Test1() {
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());
EmptyBorder emptyBorder = new EmptyBorder(15, 15, 15, 15);
EtchedBorder etchedBorder = new EtchedBorder();
CompoundBorder inner = new CompoundBorder(emptyBorder, etchedBorder);
CompoundBorder outter = new CompoundBorder(inner, emptyBorder);
JPanel panel = new JPanel(new GridBagLayout());
panel.setBorder(outter);
panel.add(new JButton("Hello"));
add(panel);
}
}
}
import java.awt.image.BufferedImage;
import javax.swing.*;
import javax.swing.border.*;
public class ThreePartBorder {
public static void main(String[] args) {
final BufferedImage bi = new BufferedImage(
400, 100, BufferedImage.TYPE_INT_RGB);
Runnable r = new Runnable() {
#Override
public void run() {
JLabel l = new JLabel(new ImageIcon(bi));
Border twoPartBorder = new CompoundBorder(
new EmptyBorder(15, 15, 15, 15),
new EtchedBorder());
Border threePartBorder = new CompoundBorder(
twoPartBorder,
new EmptyBorder(15, 15, 15, 15));
l.setBorder(threePartBorder);
JFrame f = new JFrame("Three Part Border");
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setContentPane(l);
f.pack();
f.setLocationByPlatform(true);
f.setVisible(true);
}
};
SwingUtilities.invokeLater(r);
}
}
I came back and just realized I asked a dumb question haha. Both answers above are very helpful and helped me solve the problem so I accepted one of them. Here's my solution after reading the two answers...
left.setBorder(BorderFactory.createCompoundBorder(
BorderFactory.createCompoundBorder(
BorderFactory.createEmptyBorder(10,10,10,10), // margin
BorderFactory.createEtchedBorder() // border
),
BorderFactory.createEmptyBorder(50,50,50,50) // padding
));
right.setBorder(BorderFactory.createCompoundBorder(
BorderFactory.createEmptyBorder(10,10,10,10), // margin
BorderFactory.createCompoundBorder(
BorderFactory.createEtchedBorder(), // border
BorderFactory.createEmptyBorder(50,50,50,50) // padding
)
));
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);
When I edit text in a JTextField in my Swing application on OSX, the text gets garbled. It's most pronounced when I insert or delete characters but there are artifacts just when moving the cursor around. The data is fine, but the UI rendering is not.
What causes this and how can I fix it?
I'm using com.apple.laf.AquaLookAndFeel, as in this sample program. Type in some text and move the cursor around with the arrow keys to observe the weirdness.
import java.awt.*;
import javax.swing.*;
class TextFieldDisplay {
public static void main(String[] args) {
MainWindow app = new MainWindow();
}
}
class MainWindow extends JFrame {
public MainWindow() {
try {
UIManager.setLookAndFeel("com.apple.laf.AquaLookAndFeel");
} catch(Exception e) {
System.out.println("AquaLookAndFeel is not supported on your platform.");
System.exit(1);
}
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
setVisible(true);
setMinimumSize(new Dimension(300, 100));
JPanel innerPanel = new JPanel();
JScrollPane scrollPane = new JScrollPane();
scrollPane.setPreferredSize(new Dimension(250, 20));
scrollPane.setViewportView(innerPanel);
JPanel mainPanel = new JPanel();
getContentPane().add(mainPanel);
mainPanel.add(innerPanel);
JTextField textField = new JTextField();
textField.setPreferredSize(new Dimension(250, 20));
innerPanel.add(textField);
pack();
}
}
I noticed as I was writing the SSCCE that the display issues seemed to crop up after I added the JScrollPane.
Not sure if it's relevant but I'm using Apple Java version 1.6.0_51 with a retina display.
Two things jump out at me.
Firstly, you're not initalisig your UI in the EDT, secondly, you're messing with the preferred and minimum sizes of your components.
You are not taking into consideration the font metrics when calculating the size of your components, which seems to be causing issues when it is rendering the content
Start by taking a look at Initial Threads.
import java.awt.Dimension;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.WindowConstants;
class TextFieldDisplay {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
//UIManager.setLookAndFeel("com.apple.laf.AquaLookAndFeel");
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception e) {
System.out.println("AquaLookAndFeel is not supported on your platform.");
System.exit(1);
}
MainWindow app = new MainWindow();
}
});
}
}
class MainWindow extends JFrame {
public MainWindow() {
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
setVisible(true);
// setMinimumSize(new Dimension(300, 100));
JPanel innerPanel = new JPanel();
// JScrollPane scrollPane = new JScrollPane();
// scrollPane.setPreferredSize(new Dimension(250, 20));
// scrollPane.setViewportView(innerPanel);
JPanel mainPanel = new JPanel();
getContentPane().add(mainPanel);
mainPanel.add(innerPanel);
JTextField textField = new JTextField(20);
// textField.setPreferredSize(new Dimension(250, 20));
innerPanel.add(textField);
pack();
}
}