Basically all I want to do is draw two rows of buttons for a lights out game (homework), but I don't know how to make both panels show up. I've pretty much almost no graphics before, and I don't really understand anything I'm doing.
The panels them selves work, but it just shows whichever I add second (I assume it's overwriting the previous panel)
public static void main(String[] args) {
String nButtonsString = JOptionPane.showInputDialog("How many buttons would you like?");
int nButtons = Integer.parseInt(nButtonsString);
JFrame myFrame = new JFrame();
myFrame.setTitle("Linear Lights Out Game.");
myFrame.setSize(FRAME_SIZE);
JPanel control_buttons = new Linear_Controls();
myFrame.add(control_buttons);
JPanel lights = new LinearLightsPanel(nButtons);
myFrame.add(lights);
myFrame.pack();
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.setVisible(true);
myFrame.add(control_buttons);
myFrame.add(lights);
By default a JFrame uses a BorderLayout. Also, by default components get added to the CENTER of the BorderLayout. However the CENTER can only contain a single component so only the last component added is displayed. Try:
myFrame.add(control_buttons, BorderLayout.NORTH);
Now the two components should show up.
Read the section from the Swing tutorial on Using Layout Managers for more information and examples. Also take a look at the Trail/Table of Contents link to see other useful topics for basic Swing usage.
You have to create the 2 panels A and B and add them to another panel C. Then you add C to your frame.
A bit better explained: This is what you have now:
JPanel lights = new LinearLightsPanel(nButtons);
myFrame.add(lights);
But you would like something like:
JPanel lightsA = new LinearLightsPanel(nButtonsA);
JPanel lightsB = new LinearLightsPanel(nButtonsB);
JPanel lightsC = new JPanel();
lightsC.add(lightsA);
lightsC.add(lightsB);
myFrame.add(lightsC);
Related
UPDATE: I have received justified criticism for posting non working code. I've taken that to heart and am updating this post with a complete working example. I'm also updating the description accordingly:
I have a very simple java swing GUI whose components take up what looks to be an equal amount of vertical (Y) space as is used by the largest Y extent component, but completely unnecessarily so. I have tried to shrink those components that don't need that much vertical space using preferredSize hints but to no avail.
The basic layout is simple: There's a main window and three vertical panels. The layout is a simple GridLayout (and I would prefer to keep it that way, unless someone shows me what I need cannot be done with GridLayout). All three panels seem to be occupying the same amount of vertical space, even though in the case of the sliders, this is massive waste of space. How can I get each of the sub-panes to only use as much space as they each need? i.e. I would like the two slider windows to be only as tall as the sliders and their description need to be.
The code:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class test {
public static void main(String[] arg) {
JFrame mainWindow = new JFrame();
JSlider slider1 = new JSlider(0,100,50);
JSlider slider2 = new JSlider(0,100,50);
JPanel pnlSlider1 = new JPanel();
pnlSlider1.setLayout(new GridLayout(1,1)); // 1 row, 1 column
pnlSlider1.add(new JLabel("Description for slider1"));
pnlSlider1.add(slider1);
JPanel pnlSlider2 = new JPanel();
pnlSlider2.setLayout(new GridLayout(1,1)); // 1 row, 1 column
pnlSlider2.add(new JLabel("Description for slider2"));
pnlSlider2.add(slider2);
// label should now be to the left of slider
String content = "<html>Some rather long winded HTML content</html>";
JEditorPane ep = new JEditorPane("text/html", content);
// this is the main window panel
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(3,1)); // 3 rows, 1 column
panel.add(ep);
panel.add(pnlSlider1);
panel.add(pnlSlider2);
// tie it all together and display the window
mainWindow.setPreferredSize(new Dimension(300, 600));
mainWindow.setLocation(100, 100);
mainWindow.getContentPane().add(panel);
mainWindow.pack();
mainWindow.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
mainWindow.setVisible(true);
}
}
(removed rant about not having seen any GUI coding advances in 30 years as that's not pertinent to the problem and likely won't be solved in this post either)
..components take up what looks to be an equal amount of vertical (Y) space as is used by the largest Y extent component, but completely unnecessarily so.
Yes, that is the way GridLayout is designed to work.
Use a GridBagLayout or BoxLayout or GroupLayout instead, each of which can do a single column or row of components of variable size (width and height).
I'm developing a Java GUI and I need:
A label in first row(only one label).
Starting 2nd row need to add say 100 buttons which extends to multiple lines(width shouldn't go beyond the visible screen)
In a new line one more Label
From next line say 100 buttons which extends to multiple lines(width shouldn't go beyond the visible screen)...
[OPTIONAL] If the components exceeds JFrame height then need a scroll facility to the main window (only vertical)
I have a strange results with flow layout, sometimes it stick to visible width, sometimes it sets even 500 buttons in a single row.
I have tried every layout and also multipanes. Still no luck.
Please guide.. just need an idea, No need of code
Updated with code: Sorry guys, that was my first question to stackoverflow
Thanks for prompt response
Infact i tried many, here is a simple one.
setLayout(new FlowLayout());
setTitle("JAVA GUI");
setSize(500,500);
setVisible(true);
add(new JLabel("row 1"));
JPanel panel1 = new JPanel(new FlowLayout());
for(int i=0;i<200;i++){
panel1.add(new JButton("b"+i));
}
add(panel1);
Here the panel1 is appearing in a sigle row which goes beyond the visible part of the screen.
I think this can be solved by setting maximumsize to Jframe, but no idea how to set its size to FULL SCREEN.
You can try MigLayout.
http://www.miglayout.com/
Also this question is not really a question for stack overflow. A good way to ask your question would be to post your code and tell us what is wrong with it and what it is supposed to do.
While this is not the norm for 'good' stackOverflow questions, I don't have any problem with it myself. Some people cannot deal with anything except code. I would suggest that, if you're going to post code, that you take the trouble to post code that will compile, run, and demonstrate your situation. It really helps those of us out here understand what you're seeing and what you're trying to do.
You talk about "rows"; be aware that rows and columns are terms used with things like GridLayout and GridBagLayout, but I don't think they're appropriate for what you describe.
In your description, you don't say what you want scrolled. It would appear you want the entirety of the UI scrolled, I'll assume that for now.
I would try a JPanel with BoxLayout, oriented vertically, for the overall main UI. You will put some things into that:
The first JPanel.
Another JPanel, set with FlowLayout, holding the first bunch of buttons.
Another JPanel with the next JLabel
And a fourth JPanel, set with FlowLayout, holding the second bunch of buttons.
Now, I would put the top-level panel into a JScrollPane, and then put that into the CENTER section of a Frame (with its default BorderLayout), and see what happens. To tell the truth, I'm not sure, but these are the things I would start with.
I cannot tell, without running code, why you get odd behavior sometimes.
As said in a previous comment, using a ContentPane is the way to go. Here is a working example of what you want:
public class Test {
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setTitle("JAVA GUI");
JPanel panel1 = new JPanel();
panel1.setLayout(new BoxLayout(panel1, BoxLayout.Y_AXIS));
int nbLines = 10;
for (int i = 0; i < nbLines; i++) {
JPanel linePanel = new JPanel(new FlowLayout());
linePanel.add(new JLabel("row " + i));
for(int j = 0; j < 50; j++) {
linePanel.add(new JButton("b" + j));
}
panel1.add(linePanel);
}
frame.setContentPane(panel1);
//frame.setSize(500, 500);
frame.setExtendedState(frame.getExtendedState() | JFrame.MAXIMIZED_BOTH);
frame.pack();
frame.setVisible(true);
}
}
And here is what I get:
If you want to have left-aligned buttons you can use:
JPanel linePanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
Made it work! Thank you guys! The code follows. I used BoxLayout since I thought it'd be ideal for stacking questions one on top of the other, but now I got issues with the layout... When I stack several questions the question panels start overlapping. Any thoughts?
panels1 = new MultipleChoice[5];
setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
for(int i=0; i<4; i++){
panels1[i]= new MultipleChoice();
panels1[i].setAlignmentX(CENTER_ALIGNMENT);
add(panels1[i]);
}
setVisible(true);
I'm working on designing an Online Test applet. A test has multiple choice and true/false questions. To set up a test I created two JPanel classes, one for the multiple choice question and one for the true/false questions. So when a test is created I'll just dynamically add these panels to a JPanel container according to the non-fixed number of questions.
First, how can I dynamically add new panels to a panel? I thought about declaring an array of the JPanel type. I created and then add objects of this panel class using a for loop:
MultitipleChoicePanel[] PanelArray;
for (...){
PanelArray[i] = new MultipleChoicePanel();
containerpanel.add(PanelArray[i]);
}
I don't know if this is technically possible. This is my first time using Swing, and I tried doing this but obviously it didn't work. Does anyone have an idea how correctly dynamically add these panels?
Second, which of the layout managers is best suited for the container panel in order to fit every new panel added right under the previous one? I thought about dynamically setting up a GridLayout of one column and add rows as I add panels. But I've been really struggling modifying swings dynamically.
Any suggestions?
Thank you so much for your help!
JPanel default layout is FlowLayout and add each component by default to the right so it would fit your problem.
You also may interested in swingx they have HorizontalLayout.
Example:
//in some place
JPanel myBigPanel = new JPanel();
myBigPanel.setLayout(new HorizontalLayout()); // swingx api
List<MultitipleChoicePanel> panelList = new ArrayList<>();
// panelList.add(new MultipleChoicePanel()).. .n times
for(MultipleChoicePanel mp : panelList){
myBigPanel.add(mp);
}
myBigPanel.revalidate(); // revalidate should call repaint but who knows
myBigPanel.repaint();
How to use various Layout Managers
how correctly dynamically add these panels?
After adding components to a visible GUI you need to do:
panel.add(...);
panel.revalidate();
panel.repaint();
"and then add objects of this panel class using a for loop:.....I dont know if its technically possible"
As far as an array of panels, I would do it with an arraylist and do it similarly to how you did it.
import java.util.ArrayList;
ArrayList<MultipleChoicePanel> array = new ArrayList<MultipleChoicePanel>();
for(...){
array.add(new MultipleChoicePanel());
containerPanel.add(array.get(i));
}
import java.awt.*;
import javax.swing.*;
public class JavaSwing extends JApplet {
public void init(){
Container content = getContentPane();
JScrollPane pane= new JScrollPane();
JPanel panel = new JPanel();
panel.setLayout(new BoxLayout(panel,BoxLayout.Y_AXIS));
panel.add(addPanel("title121"));
panel.add(addPanel("title112"));
panel.add(addPanel("title12"));
panel.add(addPanel("title11"));
pane.getViewport().add(panel);
content.add(pane);
}
public static JPanel addPanel(String title){
JPanel panel = new JPanel();
panel.add(new JButton(title));
return panel;
}
}
I have:
public class BaseStationFrame1 extends JFrame
{
JButton activateButton;
JButton deactivateButton;
BaseStation bs;
JTextField networkIdField;
JTextField portField;
public BaseStationFrame1(BaseStation _bs){
bs = _bs;
setTitle("Base Station");
setSize(600,500);
setLocation(100,200);
setVisible(true);
activateButton = new JButton("Activate");
deactivateButton = new JButton("Deactivate");
Container content = this.getContentPane();
content.setBackground(Color.white);
content.setLayout(new FlowLayout());
content.add(activateButton);
content.add(deactivateButton);
networkIdField = new JTextField("networkId : "+ bs.getNetworkId());
networkIdField.setEditable(false);
content.add(networkIdField);
portField = new JTextField("portId : "+ bs.getPort());
portField.setEditable(false);
content.add(portField);}
}
My problem is that i don't want the two TextFields to appear on the right of Activate and Deactivate buttons but below them. How can i fix that?
Specify your layout manager, like this:
content.setLayout(new GridLayout(2,2));
That would use the Grid Layout Manager to establish a grid with 2 columns and 2 rows, that your components would then be placed in.
The layout manager you are currently using, FlowLayout, only adds contents onto the end of the current row. it will wrap around once it reaches the constrained edge of the pane, though.
You should also check the other layout managers here
You could alternatively use GridBagLayout , but you will have to specify a GridBagConstraints object you then add alongside the individual elements, like so:
content.add(networkIdField, gridConstraints);
see more on that in the linked tutorial.
can I suggest that you use a Null Layout for the parent component?
setLayout(null);
then use a setBounds(xPos,yPos, Width, Height);
to position the components on the panel etc?
Doing this will prevent Java's UI Manager to manage the components to the Frame, Panel etc.
That seems to be the easiest and less painful way.
Regards
I have a problem with resizing some of my components in my java application. When I resize my main JFrame they keep their previous size instead of filling out the surrounding component.
For example I have in my program a JTabbedPane within a tab of another JTabbedPane (which is located within the main JFrame). I make tabs added to the inner JTabbedPane fill the whole surrounding space via various .setPreferredSize(). And then when I resize the JFrame by dragging the corner of the window, the tabs out the outer JTabbedPane resizes just fine but the JTabbedPane located within it stays the same old size.
The same thing with happens when I test it with a JScrollPane: the outer JTabbedPane resizes by the JScrollPane stays the same size.
Here below is the code for creating the tabbed panels in case you can see something obvious I missed. It's the tabPane/jsp objects in createEndGamePane() than wont resize when the JFrame is resized. mainTabPane resizes as it should.
class MyFrame extends JFrame {
private JTabbedPane mainTabPane;
private JPanel endGameInfo;
//....
private void createTabbedCenterPane(){
this.mainTabPane = new JTabbedPane();
this.endGameInfo = new JPanel();
this.createEndGamePane();
this.mainTabPane.addTab("Turneringschema", null, this.scheduleHolder, "Spelschemat för turneringen");
this.mainTabPane.addTab("Grupper & Pooler", null, this.poolInfo, "Information om grupper, lag och pooler");
this.mainTabPane.addTab("Slutspelsträd", null, this.endGameInfo, "Information om slutspelen");
this.add(this.mainTabPane, BorderLayout.CENTER);
}
private void createEndGamePane(){
JTabbedPane tabPane = new JTabbedPane();
tabPane.setPreferredSize(this.endGameInfo.getSize());
for (int i = 0; i < this.tournament.data.getGroups().size(); i++) {
EndGame e = this.tournament.data.getEndGames().get(i);;
//Create the gameTree
EndGameTreeCanvas gameTree = new EndGameTreeCanvas(e, this.endGameInfo.getSize());
//Create the ScrollPane
JScrollPane jsp = new JScrollPane(gameTree);
jsp.setPreferredSize(tabPane.getSize());
jsp.setBorder(BorderFactory.createEmptyBorder());
//Add to the endGameIndo panel
tabPane.addTab(this.tournament.data.getGroups().get(i).getName(), jsp);
}
this.endGameInfo.add(tabPane);
}
}
If you want the components to resize dynamically, you should avoid telling Swing what their size is. Instead, how about this:
JTabbedPane tabs = new JTabbedPane();
JScrollPane inner1 = new JScrollPane(myOtherComponent);
tabs.add("Scroll", inner1);
JTabbedPane inner2 = new JTabbedPane();
tabs.add("Tabs", inner2);
And that's all. No setPreferredSize().
You should read the swing layout tutorial :
http://java.sun.com/docs/books/tutorial/uiswing/layout/index.html
The layout manager i prefer is the gridbaglayout that allow maximum flexibility
( http://java.sun.com/docs/books/tutorial/uiswing/layout/gridbag.html ).
In particular, you should not use the BorderLayout.CENTER if you wish the component to fill all the available space around him.
an example with a gridbaglayout manager :
this.add(this.mainTabPane,
new GridBagConstraints(
0,0, // position
1,1, // size
1.0,1.0, // fill ratio
GridBagConstraints.CENTER, GridBagConstraints.BOTH, // position inside the cell
new Insets(2,2,2,2),0,0)); // margins
As others have said, you need to be using layout managers to handle your GUI's layout requirements.
However I recommend that your primary layout manager be a table-based layout like MatrixLayout, MigLayout, TableLayout, or any of a number of other free ones.
Using a table-based layout will simplify your GUI coding by about an order of magnitude, because it will vastly reduce the amount of layout nesting required. I find that 90% of my GUI is done with one layout manager, and the remaining 10% draws on the simpler layout managers provided with Java.
I have never had cause to use GridBagLayout and I absolute do not recommend it - it's unnecessarily complicated and make ongoing maintenance harder.