I'm creating GUI and I don't know how to resolve my problem. What I'd like to do is to create several panels from PanelClass like i did in Main.
I don't know how:
Name buttons in my Panels and gave them some functionality (Like i was trying with button b1)
Add to panel3 additional labels, and buttons.
My main class
public class Main {
JFrame f;
PanelClass panel1, panel2, panel3;
JButton b1, b2;
public Main() {
b1 = new JButton("asasa");
f = new JFrame();
f.setSize(300, 300);
f.setLayout(new GridBagLayout());
f.setVisible(true);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel1 = new PanelClass(b1, b2, panel1);
panel2 = new PanelClass(b1, b2, panel2);
panel3 = new PanelClass(b1, b2, panel3);
f.add(panel1);
f.add(panel2);
f.add(panel3);
}
public static void main(String[] args) {
Main m = new Main();
}
}
My Panel class
public class PanelClass extends JPanel {
public PanelClass(JButton btn, JButton btn1, JPanel p) {
super();
p = new JPanel(new GridBagLayout());
btn = new JButton();
btn1 = new JButton();
GridBagConstraints c = new GridBagConstraints();
c.gridx = 0;
c.gridy = 0;
p.add(btn, c);
c.gridx = 0;
c.gridy = 1;
p.add(btn1, c);
add(p);
}
}
A component can only exist in one visible container at a time (unless it is being used as a flyweight renderer). So putting the same buttons into 3 panels will not work.
The code passes a button(s) in the constructor of PanelClass which is(are) ignored. Instead 2 new button instances are created. Just assign the passed buttons to the ..I was going to say 'class level attributes' when I noted they were not. Entirely remove
btn = new JButton(); and the text passed in the button constructor will appear.
For events, see How to Write an Action Listener.
Try to read the official Swing tutorial. It explains how to add panels, labels, etc.
To edit label names you could use setText(String name) method. To add functionalities to buttons you must implement a listener in each one. Add labels like you do in other panels, I don't see the problem.
To add "events" like click and mouse hovers etc - you must implement the correct "Listener" for the Widget. Go through any good tutorial on Swing and it will tell you everything about it. Widgets on screen are regular objects as well, so they can be added to "Collections", iterated and played around with, like regular objects. Take note of THREAD complexities and warning 'Cross-Thread invocation is Injurious To Your Program'.
Related
I'm writing a programm with a complicated TabbedPane, with lots of elements. Since I hit the Byte-limit in one of my classes, I decided to split the class into Initialisation/Button Listeners and the actual GridBagLayout. But now I'm having trouble getting it to work. My Main Class looks like this:
public class Main{
JFrame mainFrame = new JFrame("");
JTabbedPane tabpane = new JTabbedPane();
JPanel panelTab1 = new Tab1();
JScrollPane scrollTab2 = new JScrollPane(new Tab2());
JScrollPane scrollTab3 = new JScrollPane(new Tab3());
JPanel panelTab4 = new Tab4();
JMenuBar bar = new MenuBar();
public Main(){
tabpane.add("Tab1", panelTab1);
tabpane.add("Tab2", scrollTab2);
tabpane.add("Tab3", scrollTab3);
tabpane.add("Tab4", panelTab4);
mainFrame.getContentPane().add(tabpane);
mainFrame.setSize(1920,1080);
mainFrame.setExtendedState(JFrame.MAXIMIZED_BOTH);
mainFrame.setVisible(true);
mainFrame.validate();
mainFrame.setJMenuBar(bar);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable(){
public void run(){
new Main();
}
});
}}
Tab3 is the culprit so here are the two classes I split.
public class Tab3 extends JPanel {
JPanel Annex = new JPanel();
//A Bunch of Labels and Buttons
.
.
.
public Tab3(){
//ActionListeners for the Buttons
this.setLayout(new BorderLayout());
this.add(Annex,BorderLayout.WEST);
this.add(Bsp,BorderLayout.EAST);
}}
All the GridBagLayout is in the following class:
public class Tab3Layout extends Tab3{
public Tab3Layout(){
Annex.setLayout(new GridBagLayout());
GridBagConstraints co1 = new GridBagConstraints();
co1.gridx = 0;
co1.gridy = 0;
co1.anchor = GridBagConstraints.FIRST_LINE_START;
co1.weighty = 1.0;
Annex.add(Annex1, co1);
//and so on...
}}
Now my question is, how do I get this to work? Right now if I compile, Tab3 is just empty. If everything is in one class it works exactly how I want, but the code is just much too long. Seems to me like I'm missing a line in the Tab3 class, but even after hours of tinkering and searching I have no idea how to solve this. Everything I tried just produced more errors.
The problem is in iheritance. Tab3Layout has its own Annex JPanel (inherited from Tab3), which it is modifying and adding components to, while Tab3 class is inserting its Annex, which is initialized via new JPanel() and you do nothing else with it. Tab3Layout class never even touches Annex panel you intialize and add in Tab3 .
public class Tab3 extends JPanel {
JPanel Annex = new JPanel(); // <----- this, an empty JPanel
//A Bunch of Labels and Buttons
public Tab3(){
//ActionListeners for the Buttons
this.setLayout(new BorderLayout());
this.add(Annex,BorderLayout.WEST); // <----- is inserted here
this.add(Bsp,BorderLayout.EAST);
}}
You will get an error if you delete new JPanel(), which will illustrate that both classes are doing work on different objects, which just happen to be named the same. You need to pass all components/panels you want to appear in Tab3 to Tab3Layout to modify, then you can retrieve them later with getters. Another way would be to create AnnexPanel class, which itself would be extending JPanel class. It would set its own layout, components etc. and be able to be added directly. Following Single Responsibility Principle would be best, if your classes grow in size. If it's 200+ lines of code, you should consider refactoring it. If you will allow your class to grow like 3000+ lines of code, you will have a bad time. Try to forsee where you can create new class/method in early stages of development. See KISS principle .
Well..I would split those in different way.
My Tab3Layout class. Annex panel is injected via constructor, you can set a setter for that, but remember to not call createAnnex() before injection. Anyway, compiler will make you remember.
public final class Tab3Layout {
private JPanel Annex;
JPanel Annex1; //just to avoid compiler error
private GridBagLayout gridBagLayout;
private GridBagConstraints co1;
public Tab3Layout(JPanel Annex) {
this.Annex = Annex;
this.gridBagLayout = new GridBagLayout();
this.co1 = new GridBagConstraints();
}
public void createAnnex() {
this.Annex.setLayout(gridBagLayout);
this.co1.gridx = 0;
this.co1.gridy = 0;
this.co1.anchor = GridBagConstraints.FIRST_LINE_START;
this.co1.weighty = 1.0;
this.Annex.add(Annex1, co1);
}
public JPanel getAnnex() {
return this.Annex;
}
}
And then the Tab3 class:
public class Tab3 extends JPanel {
JPanel Annex;
Tab3Layout tab3Layout;
public Tab3() {
super();
this.Annex = new JPanel();
this.tab3Layout = new Tab3Layout(Annex);
this.tab3Layout.createAnnex();
this.setLayout(new BorderLayout());
this.add(tab3Layout.getAnnex(), BorderLayout.WEST);
this.add(new JPanel(), BorderLayout.EAST);
}
}
Look at my GridBagManager repo, it can give you an idea how to set layout with another class.
You can also extend Tab3Layout with JPanel. And remember to set anchor and fill with GridBagConstraints.
And Java naming convention.
JPanel Annex = new JPanel();
GridBagConstraints co1 = new GridBagConstraints();
to
JPanel annexPanel = new JPanel();
GridBagConstraints gridBagConstraints = new GridBagConstraints();
Personally I use gbc for GridBagConstraints object, as you will see in my repo I mentioned above.
Edit:
I think you should split your implementation into couple of smaller classes. That would be professional aproach. Refactor your code. For starters you can make every panel its own class extending JPanel (like i suggested with AnnexPanel class).
Edit2: createAnnex() can return JPanel type, reducing your boilerplate code, your call then would be as follows:
this.add(Tab3Layout.createAnnex(), co1);
instead of
Tab3Layout.createAnnex();
this.add(Tab3Layout.getAnnex(), co1);
Maybe even take createAnnex() to constructor (assuming class extends JPanel) if it's a singleton.
Question is quite simple. I realized my code could be cleaned up a little if I was allowed to add components to a JPanel like this:
//north panel
JPanel northPanel = new JPanel(new GridLayout(0,3));
btnAdd = new JButton("Add");
btnEdit = new JButton("Edit");
btnDelete = new JButton("Delete");
northPanel.add(btnAdd, btnEdit, btnDelete);
instead of like this:
//north panel
JPanel northPanel = new JPanel(new GridLayout(0,3));
btnAdd = new JButton("Add");
btnEdit = new JButton("Edit");
btnDelete = new JButton("Delete");
northPanel.add(btnAdd);
northPanel.add(btnEdit);
northPanel.add(btnDelete);
Is there a way to do it? I've looked around SO and the internet, including Oracle's documentation and I know there's not an .add() method built to this particular syntax, but I would like to know if there is another method with this functionality.
Good Solution:
Thank you all for your feedback. It does make sense that a single statement would actually be more convoluted if accomplished in the way I described. L. Mehmeti suggested storing the components in an array and creating a method which adds all components in the array, which suits the question perfectly. In this way, when there gets to be a lot of components, the order is easily kept track of, instead of having to search through a bunch of separate constructors and add statements.
I am very sorry, but i guess there is no way to do that. The only way i think is writing your own method. For example:
public static void main(String[] args) {
Example main = new Example("Example");
}
public Example(String title) {
super(title);
JPanel panel = new JPanel();
panel.setLayout(new FlowLayout());
JComponent[] components = new JComponent[3];
components[0] = new JLabel("Hello!");
components[1] = new JLabel("How are you?");
components[2] = new JLabel("I am fine. Thanks");
addComponents(panel, components);
add(panel);
setVisible(true);
}
public void addComponents(JComponent target, JComponent[] components) {
for(JComponent component : components) {
target.add(component);
}
}
Hope I could help.
You could create a method and call it in your init method.
public void addComponentsJ()
{
northPanel.add(btnAdd);
northPanel.add(btnEdit);
northPanel.add(btnDelete);
}
this will allow you to use
addComponentsJ()// to add all the components..
but, this is relatively the same as what you are doing... just relocating the add method calls to another method.
thus allowing you to "add them all in one statement"
Swing does not support the adding of components in one statement... the only way is to relocate calls to another method.
I'm having some issues with my GridBagLayout. I have created a JPanel (in this case it's called mainPanel), whose layout has been set to GridBagLayout. I have specified the constraints for each JButton, and added the constraints to each button. Now, when I run my code, the buttons are always next to each other, irrespective of the gridx/gridy value that I indicate in the constraints. Furthermore, the buttons are always at the center of the JFrame, when I would like one button to appear at the top right, top left, and south.
import javax.swing.*;
import java.awt.*;
public class test {
public static void main (String[] args) {
myJFrame test = new myJFrame();
}
}
class myJFrame extends JFrame {
public myJFrame () {
setSize(500,500);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainPanel myPanel = new mainPanel();
add(myPanel);
setVisible(true);
}
}
class mainPanel extends JPanel {
public mainPanel(){
setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
c.anchor = GridBagConstraints.NORTHWEST;
c.gridx = 1000;
c.gridy= 1;
add(new JButton("1"),c);
c.anchor = GridBagConstraints.NORTHEAST;
c.gridx = 100;
c.gridy= 1;
add(new JButton("2"),c);
c.anchor = GridBagConstraints.SOUTH;
c.gridx = 200;
c.gridy= 1;
add(new JButton("3"),c);
}
}
This is what i get when i run the code
Now, when I run my code, the buttons are always next to each other, irrespective of the gridx/gridy value that I indicate in the constraints.
Correct, you can't just specify random cells. A component must be located in each cell.
Furthermore, the buttons are always at the center of the JFrame,
Yes, this is the default behaviour if you don't specify a weightx/weighty constraint.
Read the section from the Swing tutorial on How to Use GridBagLayout for more information on constraints and working examples.
Why are you picking random x locations like 100, 200, 1000? Maybe a horizontal BoxLayout would be a better layout manager. You can add the components and then add space between them:
panel.add( button1 );
panel.add( Box.createHorizonalStrut(100);
panel.add( button2 );
panel.add( Box.createHorizonalStrut(200);
Or maybe use a FlowLayout and specify the "gap" between each component.
I am new in java applications and I am trying to create a window with 3 buttons in a row at the bottom of the window with extended size. However gridheight doesn't have any affect on my buttons. gridwidth works fine.
Can you give me a feedback on what I am doing wrong? I guess I haven't understand something correctly.
Bellow is my code and the output window.
Thanx in advance!
private JButton button1;
private JButton button2;
private JButton button3;
public SessionTasksPage()
{
JPanel p1=new JPanel(new GridBagLayout());
JPanel p2=new JPanel();
button1 = new JButton("b1");
button2 = new JButton("b2");
button3 = new JButton("b3");
GridBagConstraints gbc =new GridBagConstraints();
//gbc.insets = new Insets(1,1,1,1);
gbc.gridheight = 5;
gbc.gridwidth = 5;
gbc.weightx=15;
gbc.weighty=15;
gbc.fill = GridBagConstraints.BOTH;
p1.add(button2,gbc);
p1.add(button3,gbc);
p1.add(button1,gbc);
add(p1,BorderLayout.SOUTH);
add(p2,BorderLayout.NORTH);
EventHandler1 event1 = new EventHandler1();
button1.addActionListener(event1);
//window terminate setting
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//window size
setSize(600,400);
//pack();
//make window visible
setVisible(true);
//window title
setTitle("HCI-Projet");
//voice command
//new AePlayerWave("bin/sounds/login.wav").start();
}
public class EventHandler1 implements ActionListener
{
public void actionPerformed(ActionEvent event1) {
System.exit(0);
}
}
The problem lies the layout of your main panel. BorderLayout, which you use on that panel, has one large central area (BorderLayout.CENTER), and many smaller areas (such as NORTH and SOUTH). The layout will force anything put anywhere other than CENTER to take up the smallest amount of room possible, and max out the remaining room with what is in the CENTER area (with nothing, in this case). Since you're adding p1 as SOUTH, it keeps the vertical component of p1 as small as it can. If you add p1 as CENTER, it should fix your problem.
As a side note, if all the rows/columns in your grid will have the same height/width, you may find using GridLayout much easier than GridBagLayout.
The problem is the JPanel p1. The space of the panel is created by the standard layout, and if you just use add(p1,BorderLayout.SOUTH);, it won't change.
To make it visible you could use a Border:
p1.setBorder(BorderFactory.createLineBorder(Color.black));
Use a different layout or a GUI builder.
probably a simple question here working on learning to make a GUI using swing and making mild headway but hit another speed bump. I am trying to keep GUI components grouped in different classes to keep my classes small and allow a more flexible GUI, but I have one component built how do I call it to my main class. Posted below is code to make the frame and the component. I would imagine there is an issue with the way I am calling but am running out of ideas on how else to call it. Any thoughts would be appreciated.....Wasn't very clear with the question trying to add the component to the JFrame in frmMainMenu, issue is that the component doesn't appear in the Frame when run currently
Main Class with JFrame
public class frmMainMenu {
public static void main(String main[]){
//Create Frame
JFrame frmMainMenu = new JFrame();
//Define Layout Manager
GridBagLayout gridBag = new GridBagLayout();
GridBagConstraints c = new GridBagConstraints();
frmMainMenu.setLayout(gridBag);
//Add Components
//Create Left Container
c.fill = GridBagConstraints.VERTICAL;
c.weighty = 1;
c.gridx = 0;
c.gridy = 1;
c.ipadx = 30;
frmMainMenu.add(new comLeftToolBar(),c);
frmMainMenu.setExtendedState(JFrame.MAXIMIZED_BOTH);
frmMainMenu.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
//Display Frame
frmMainMenu.setVisible(true);
}
}
Component Code
public class comLeftToolBar extends JPanel{
public comLeftToolBar() {
JPanel comLeftContainer = new JPanel();
GridBagLayout leftGridBag = new GridBagLayout();
comLeftContainer.setLayout(leftGridBag);
GridBagConstraints b = new GridBagConstraints();
JToolBar comLeftToolBar = new JToolBar(JToolBar.VERTICAL);
b.gridx = 0;
b.gridy = 0;
b.ipady = 50;
JButton comNavButton = new JButton();
JButton comProButton = new JButton();
comLeftToolBar.add(comNavButton);
comLeftToolBar.add(comProButton);
comLeftContainer.add(comLeftToolBar,b);
comLeftContainer.setBorder(BorderFactory.createLineBorder(Color.black));
}
}
issue is that the component doesn't appear in the Frame when run currently
Your class is a panel. But then you create another panel (comLeftContainer) and add components to this panel. But you don't add any components to the ComLeftToolBar panel so it remains empty.
For a simple solution, at the bottom of your class you can use:
add( comLeftContainer );
Of course this is not the best solution. This will give you a structure of:
JPanel
JPanel
JToolbar
button
button
There is no need to have such a complicated structure. A toolbar is a component that be added directly to the frame.
If you want to create a class that you can add to the frame then take a look at the Swing tutorial on How to Use Tool Bars for a better structure.