how to add a JLabel simple text over/above a JTextField.
I tried many commands as you can see in my code but nothings works.
this is a snapshot of my code
private JPanel createTextPanel() {
int panelWidth = PANEL_SIZE.width;
int panelHeight = PANEL_SIZE.height/3;
Dimension panelSize = new Dimension(panelWidth,panelHeight);
JPanel textPanel = new JPanel();
textPanel.setPreferredSize(panelSize);
//textPanel.setLayout(null);
/* Add text */
JLabel Text_RED = new JLabel();
Text_RED.setText("Red");
//Text_RED = new JLabel("\nRED\n");
//Text_RED.setHorizontalTextPosition(SwingConstants.TOP);
//Text_RED.setVerticalAlignment(SwingConstants.TOP);
Red = new JTextField(3);
//Red.setVerticalAlignment(JTextField.TRAILING );
Red.setLocation(100,100);
//Red.setLocation(50, 50);
JLabel Text_Green = new JLabel("Green");
Green = new JTextField(3);
JLabel Text_Blue = new JLabel("Blue");
Blue = new JTextField(3);
//setLayout(new GridLayout(2,2,10,10));
textPanel.add(Text_RED);
textPanel.add(Red);
textPanel.add(Text_Green);
textPanel.add(Green);
textPanel.add(Text_Blue);
textPanel.add(Blue);
return textPanel;
}
Suggestions:
Don't use null layouts and absolute positioning. While it seems initially that using these tools is the easiest way to create complex GUI's, it's really a newbie fallacy, as the more you understand and use the layout managers, the more you'll find that they make the job of creating GUI's much easier, and the results much more attractive.
Learn about and use the layout managers. Tutorial link.
Consider using a BorderLayout and adding your JLabel BorderLayout.CENTER and the JTextField at BorderLayout.PAGE_END. As a side note, I generally avoid placing JTextFields in a BorderLayout.CENTER position since this will cause horizontal stretching of the field if the GUI changes size, which I don't think is aesthetically pleasing.
Related
I need to do an assignment and create a calculator. It's a beginner Java course, so keep in mind that I'm no expert. It shouldn't look spectacular, so the easiest way to achieve the below would be great.
The inner workings of it is fine, but drawing it has been a real headache.
We've only gotten exposure to flowlayout so far...and in this instance it's not what I want at all. Let me start of by telling you what layout I'm looking for:
At the top a heading spreading across the calculator, with perhaps a
background fill.
Then below that, 2 buttons next to each other.
Below that, two labels next to each other.
Then two text field next to each other.
Below that, two labels next to each other.
Then two text field next to each other.
I tried drawing it here, but it doesn't format correctly. If I can put it in HTML it would basically be a simple table, with 6 rows and 2 columns. But the top row must span across both columns.
Flowlayout just put everything next to each other from left to right.
After that I tried using GridLayout, but the top heading was the problem here, as it didn't span across both columns.
Here is my code so far:
public class TripCalculator extends JFrame implements ActionListener {
public static final int WIDTH = 400;
public static final int HEIGHT = 300;
public static final int NUMBER_OF_CHAR = 4;
public JTextField stopTime, distance, tripTime, speed;
public TripCalculator() {
setSize(WIDTH, HEIGHT);
WindowDestroyer listener = new WindowDestroyer();
addWindowListener(listener);
Container contentPane = getContentPane();
contentPane.setLayout(new FlowLayout());
JLabel heading = new JLabel("HEADING");
contentPane.add(heading);
contentPane.setLayout(new FlowLayout());
JButton addStop = new JButton("BUTTON1");
addStop.addActionListener(this);
JButton addLeg = new JButton("BUTTON2");
addLeg.addActionListener(this);
contentPane.add(addStop);
contentPane.add(addLeg);
JLabel subHead1 = new JLabel("LABEL1");
contentPane.add(subHead1);
JLabel subHead2 = new JLabel("LABEL2");
contentPane.add(subHead2);
stopTime = new JTextField(NUMBER_OF_CHAR);
contentPane.add(stopTime);
distance = new JTextField(NUMBER_OF_CHAR);
contentPane.add(distance);
JLabel subHead3 = new JLabel("LABEL3");
contentPane.add(subHead3);
JLabel subHead4 = new JLabel("LABEL4");
contentPane.add(subHead4);
tripTime = new JTextField(NUMBER_OF_CHAR);
contentPane.add(tripTime);
speed = new JTextField(NUMBER_OF_CHAR);
contentPane.add(speed);
}
}
I would greatly appreciate if anyone can show me in the right direction.
Flowlayout or Gridlayout by themselves won't help you. Either you can use Gridbaglayout, or a combination of layouts such as FlowLaout+Gridlayout.
If you are drawing a calculator, I am assuming you are drawing something like this :
Where you have title information at the top, a calculator keypad in the middle, and some other buttons at the bottom :
This could be achieved with a vertical box layout, with flowlayouts at the top and bottom, and in the middle a grid layout with all the number keys.
But... without you showing a diagram of what you want its very difficult to say.
Here's an example of using multiple Layout Managers as you can see you can use more than one, but you should use more than one JPanel to achieve what you want.
Also a recommendation is: Don't extend from JFrame, instead create a JFrame object as I did in this example and here's why you shouldn't do that.
import java.awt.*;
import javax.swing.*;
public class LayoutManagersExample {
public static void main(String args[]) {
new LayoutManagersExample();
}
public LayoutManagersExample() {
JFrame frame = new JFrame("Layout Managers Example");
JPanel topPane = new JPanel();
JPanel midPane = new JPanel();
JPanel panesHolder = new JPanel();
JLabel label = new JLabel("Top label");
JTextField field = new JTextField();
field.setColumns(5);
topPane.setLayout(new FlowLayout());
midPane.setLayout(new GridLayout(3, 2));
topPane.add(label);
topPane.add(field);
midPane.add(new JButton("Button 1"));
midPane.add(new JButton("Button 2"));
midPane.add(new JButton("Hello I'm a button"));
midPane.add(new JButton("HEY! Click me :)"));
midPane.add(new JButton("I love you"));
midPane.add(new JButton("This is another button"));
panesHolder.setLayout(new BoxLayout(panesHolder, BoxLayout.Y_AXIS));
panesHolder.add(topPane);
panesHolder.add(midPane);
frame.add(panesHolder);
frame.setSize(400, 300);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
}
}
And this is how it looks like:
I'm making a simple Jeopardy-esque game:
using Java Swing. It's obviously a JFrame with a JPanel in it and buttons in rows.
Now what I need is to add a layered panel with a centered and wrapped text in it:
Which I can remove later. I already tried using JTextPane and JTextArea and JPanel, none of those want to even display. The best effect I have achieved with AWT Panel, it does display but I can't center or wrap text in it.
Here's some code for which I appologise, I would usually try to make it short and readable but since it's not working I don't know what to do with it to make ti look better:
JLabel questionLabel = new JLabel(questionList.get(randomNumber).getQuestion(), SwingConstants.CENTER);
Font font = new Font("Arial", Font.PLAIN, 20);
//------------------JTextPane--------------------
JTextPane questionPane = new JTextPane();
questionPane.setForeground(Color.WHITE);
questionPane.setSize(gameWidth, gameHeight);
questionPane.setText(questionList.get(randomNumber).getQuestion());
questionPane.setFont(font);
questionPane.setEditable(false);
//------------------AWT panel--------------------
Panel awtPanel = new Panel();
awtPanel.setBackground(Color.blue);
awtPanel.setSize(game.getWidth(),game.getHeight());
Label labelQuestion = new Label("<html>" + questionList.get(randomNumber).getQuestion() + "</html>", Label.CENTER);
labelQuestion.setFont(font);
awtPanel.setForeground(Color.white);
awtPanel.add(labelQuestion);
//------------------JPanel-----------------------
JPanel layeredPanel = new JPanel();
layeredPanel.setBackground(Color.blue);
layeredPanel.setSize(game.getWidth(),game.getHeight());
JLabel jLabelQuestion = new JLabel("<html>" + questionList.get(randomNumber).getQuestion() + "</html>", SwingConstants.CENTER);
jLabelQuestion.setFont(font);
layeredPanel.setForeground(Color.WHITE);
layeredPanel.add(jLabelQuestion, BorderLayout.CENTER);
game.getLayeredPane().add(layeredPanel, JLayeredPane.DEFAULT_LAYER);
try {
Thread.sleep(3000);
} catch (InterruptedException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
button.setEnabled(false);
font = new Font("Arial", Font.PLAIN, 16);
button.add(jLabelQuestion, BorderLayout.CENTER);
button.setDisabledIcon(new ImageIcon(source.getScaledInstance(gameWidth/4, gameHeight/5, java.awt.Image.SCALE_SMOOTH)));
questionList.remove(randomNumber);
logger.info(questionList.size());
game.getLayeredPane().remove(layeredPanel);
UPDATE: I chnaged to SWT rather than Swing, and I use the StackLayout with a few Composites in it, and just change between them as I see fit.
You can generally solve issues like this with a JLabel.
I would recommend encapsulating the above grid in the BorderLayout.CENTER of another pane, perhaps a new content pane. Then, add the caption to BorderLayout.NORTH.
As a more tangible example,
private void createContent() {
this.getContentPane().setLayout(new BorderLayout());
//establish the panel currently set as center, here labeled "everythingElse"
this.getContentPane().add(everythingElse, BorderLayout.CENTER);
//Create a JLabel with your caption
JLabel jlbl = new JLabel("Question");
//format that caption, most details being rather obvious, but most importantly:
jlbl.setHorizontalAlignment(SwingConstants.CENTER); //keeps text centered
this.getContentPane().add(jlbl, BorderLayout.NORTH); //add it to the top of the panel
//...other cleanup operations...
}
The issue with grid panes is that they have a limited tolerance for the number of components visible in them. If you overload one, it won't show. For BorderLayout panes, you can easily swap new items into and out of them.
For efficiency's sake, I might recommend compiling this JLabel as a final somewhere else in your code, and holding onto it for when you need it. This way, you will also dodge overhead from repeatedly creating the label object.
Lastly, avoid AWT whenever you can. It's been deprecated for an excess of ten years, and if you do use it you will run into numerous critical problems involving heavyweight and lightweight component incompatibilities. If you intend to use another windowing kit, consider implementing the new standard, JavaFX, with a JFXPane-- it's much more tolerant of HTML syntax, as well.
This is my first time really using graphics with Java.
I have a problem where I'm trying to populate a JScrollPane with an undefined number of panels (The following code is just a test; I know it's written using bad practices, but it's a test to see how to do it is all).
In the final program I'm going to have an ArrayList of orders (ArrayList size not predetermined), and in a JScrollPane I'm going to have a JPanel that holds a JPanel (each containing several labels) that will have details of each order.
here's the current test code (the JScrollPane is simply named scrollPane):
JPanel panel = new JPanel();
GroupLayout experimentLayout = new GroupLayout(panel);
ArrayList<JPanel> panelArray = new ArrayList();
for(int i = 0; i <3; i++){
JPanel panel2 = new JPanel();
JLabel label2 = new JLabel("Hello");
JLabel label3 = new JLabel("Hi");
panel2.add(label2);
panel2.add(label3);
//panel.add(panel2);
panelArray.add(panel2);
}
experimentLayout.setHorizontalGroup(
experimentLayout.createParallelGroup()
.addComponent(panelArray.get(0))
.addComponent(panelArray.get(1))
.addComponent(panelArray.get(2))
);
experimentLayout.setVerticalGroup(
experimentLayout.createSequentialGroup()
//.addGroup(experimentLayout.createParallelGroup(GroupLayout.Alignment.LEADING)
.addComponent(panelArray.get(0))
.addComponent(panelArray.get(1))
.addComponent(panelArray.get(2))
);
scrollPane.setViewportView(panel);
When this runs, the JPanels that contain the labels are displayed horizontally (next to each other) instead of under one another.
Any help on how I could go about displaying them vertically would be a great help - Thank you all :)
You might find GridLayout to be useful.
I have used the createVerticalGlue() successfully on a number of times. However in the following screen building code it is not working. I am still wondering why.
The situation is that I have two JPanels (leftPanel, rightPanel) within another Panel (centralPanel). Each of these two panels will host two JComponents using a BoxLayout Y-Axis. I want to distribute the remaining free space before, between and after the two JComponents.
I know that I can use empty borders and rigid areas to solve the problem but it happens that I am a bit hard headed!
My appologies for the long question.
public class MemberGUI extends JFrame {
JPanel contPane = (JPanel) this.getContentPane();
JPanel centralPanel = new JPanel();
JPanel leftPanel = new JPanel();
JPanel rightPanel = new JPanel();
JPanel lowerPanel = new JPanel();
JLabel title = new JLabel("Add/Delete Member");
JLabel nameLbl = new JLabel("Member's name");
JLabel idLbl = new JLabel ("Member ID");
JTextField nameFld = new JTextField(10);
JTextField idFld = new JTextField(10);
public void buildMe(){
//LayoutManagers
contPane.add(title,BorderLayout.PAGE_START);
contPane.add(centralPanel,BorderLayout.CENTER);
contPane.add(lowerPanel,BorderLayout.PAGE_END);
centralPanel.add(leftPanel);
centralPanel.add(rightPanel);
leftPanel.setLayout(new BoxLayout(leftPanel,BoxLayout.Y_AXIS));
rightPanel.setLayout(new BoxLayout(rightPanel,BoxLayout.Y_AXIS));
//leftPanel.add(Box.createRigidArea(new Dimension(0,50)));
leftPanel.add(Box.createVerticalGlue());
leftPanel.add(idLbl);
leftPanel.add(Box.createVerticalGlue());
leftPanel.add(nameLbl);
leftPanel.add(Box.createVerticalGlue());
//rightPanel.add(Box.createRigidArea(new Dimension(0,50)));
rightPanel.add(Box.createVerticalGlue());
rightPanel.add(idFld);
rightPanel.add(Box.createVerticalGlue());
rightPanel.add(nameFld);
rightPanel.add(Box.createVerticalGlue());
// JFrame Settings
this.setSize(500,400);
this.setResizable(false);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
this.setVisible(true);
}
}
afaics, centralPanel has default layoutManager, which is FlowLayout. This always sizes its children to their prefSize, so the glue never comes into play.
Nesting containers comes at a price (which nesting wizards like #Andrew happily pay :-) Also, it's not entirely trivial to get right (f.i. replace the upper textField with a comboBox to see the mis-alignment). In the longer run, there's hardly a route around learning to master a more powerful manager, like f.i. MigLayout (my current personal favorite)
I had problem using a very simple frame containing two JPanel.
The problem is on the layout of the Center JPanel that contains four JButton.
How can I set a better size for buttons or directly for JPanel that uses the GridLayout. On the picture the problem:
alt http://img42.imageshack.us/img42/4601/horrible.jpg
!
Here the code: ` JFrame window = new JFrame("Horrible! LOL");
JTextField textField = new JTextField("");
textField.setPreferredSize(new Dimension(200,20));
JPanel textPanel = new JPanel(new FlowLayout(FlowLayout.CENTER));
textPanel.add(textField);
window.add(textPanel, BorderLayout.NORTH);
JButton plus = new JButton("+");
//plus.setPreferredSize(new Dimension(50,50)); nothing would change
JButton minus = new JButton("-");
JButton per = new JButton("x");
JButton divide = new JButton("/");
JPanel prova = new JPanel(new GridLayout(2,2,10,10));
Dimension d = new Dimension(20,20);
prova.setMaximumSize(d); // nothing changed!
prova.add(plus);
prova.add(minus);
prova.add(per);
prova.add(divide);
window.add(prova, BorderLayout.CENTER);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setSize(250,300);
window.setResizable(false);
window.setVisible(true);`
Which is a good solution?
Kind regards
Unfortunately gridlayout doesent respect preferred sizes. But still if you want to stick to grid layout then you can try something like this:
public static JComponent wrap(JComponent comp)
{
JPanel panel = new JPanel();
panel.add(comp);
return panel;
}
And then instead of direclty adding in to prova add like this:
prova.add(wrap(plus));
prova.add(wrap(minus));
prova.add(wrap(per));
prova.add(wrap(divide));
Tested, Works perfect!!
There are other better ways though
That's what happen to me:
It's definitely attached to the upper edge of the grid.
alt text http://img96.imageshack.us/img96/9431/stillnot.jpg
Even if in this case, in the wrap method I can set the preferredSize of buttons/comp, every buttons is on its own edge. What about others solutions. How would you position buttons for a calculator?
Kind regards and thanx angain!