I'm playing around with some swing guis and am trying to create a basic program. This program is going to have a tabbed pane with a varying amount of tabs depending on the size of an array. (My end goal is to have users change the amount of items in the array, therefore changing the amount of tabs).
Each tab is going to have the exact same components, text area, table and a few buttons and labels. What I would like to do is instead of coding these tabs individually and rewriting my code over and over what I want to do is create a class to put all my components into.
I am however kind of stumped. This is my class for creating the tabs:
public class LocaleTab {
public LocaleTab(){
JPanel tab = new JPanel();
JLabel label = new JLabel();
label.setPreferredSize(new Dimension(300, 300));
tab.add(label);
}
}
And here's my code that I'm trying to call with it:
LocaleTab tab1 = new LocaleTab();
JTabbedPane localesTabPane = new JTabbedPane();
localesTabPane.add(tab1);
I'm getting an error when I try and compile this. I'm thinking my methodology is probably completely wrong.
The method add(Component) in the type JTabbedPane is not applicable
for the arguments (LocaleTab)
One are that concerns me is when I try to use the data in the tables and text areas in each tab(event listeners is what I'll be using i think? I haven't gotten to that stage yet though!) how will I target the individual tabs components?
Change to:
public class LocaleTab extends JPanel {
public LocaleTab(){
JLabel label = new JLabel();
label.setPreferredSize(new Dimension(300, 300));
add(label);
}
}
Probably you are looking for something close to this:
public class LocaleTab {
private JPanel tab;
public LocaleTab() {
tab = new JPanel();
JLabel label = new JLabel();
label.setPreferredSize(new Dimension(300, 300));
tab.add(label);
}
public JPanel getTabPanel() {
return tab;
}
}
And use LocaleTab as shown below.
LocaleTab tab1 = new LocaleTab();
JTabbedPane localesTabPane = new JTabbedPane();
localesTabPane.add(tab1.getTabPanel());
Additionally to know about how JTabbedPane works please take a look here: How to Use Tabbed Panes
Related
I'm trying to do scrollable list of items that may have buttons inside of them. It's contained within JTabbedPane, and after thorough Googling I'm still not sure how to proceed.
A picture of what I'm trying to achieve:
Best thing that comes to mind is JScrollPane with items as JPanels with BoxLayout and they have "name of item | button | button", although I might be plain wrong and JScrollPane is unable to accept multiple Components.
What I need help with is adding these JPanels to a JScrollPane. How to do that? I tried simple "this.add(name of panel)" and it doesn't work.
// MainWindow:
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("Overview", new OverviewTab());
tabbedPane.addTab("Warehouse", new WarehouseTab());
tabbedPane.addTab("History", new HistoryTab());
public class WarehouseTab extends JScrollPane {
WarehouseTab(){
this.setBorder(null);
this.add(new WarehouseItem());
this.add(new WarehouseItem());
this.add(new WarehouseItem());
this.setVisible(true);
}
public class WarehouseItem extends JPanel {
WarehouseItem(){
this.setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
JButton sell = new JButton("Sell");
JButton tax = new JButton("Return tax");
JLabel name = new JLabel("Item name");
this.add(name);
this.add(tax);
this.add(sell);
}
I also tried packing my JPanels into Container and then pointing JScrollPane's viewport to it, as suggested on some other forums, but it didn't work either. What else should it try?
Any suggestions would be appreciated, thanks.
although I might be plain wrong and JScrollPane is unable to accept multiple Components.
Yes, you're right, JScrollPane manages a single "view". What you should so is start with a separate JPanel which acts as the "primary" container for your other elements and then wrap that in a JScrollPane
public class WarehouseTab extends JPanel {
public WarehouseTab() {
setLayout(new BorderLayout());
add(new JScrollPane(new WarehousePane());
}
}
public class WarehousePane extends JPanel {
WarehousePane(){
setLayout(...); // Set an appropriate layout for overall needs
this.add(new WarehouseItem());
this.add(new WarehouseItem());
this.add(new WarehouseItem());
}
Also, have a look at How to Use Scroll Panes and the JavaDocs which provide more information about how JScrollPane works
I am trying to figure why I can't see my labels like when I try to put 2 labels into 1 panel they dissapear, the only way I can seem to get it to work is if I add everything to JFrame with no type of hierarchy.
import javax.swing.*;
import java.awt.*;
public class GUI extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
static JRadioButton tirebg1 = new JRadioButton();
static JRadioButton tirebg2 = new JRadioButton();
static JRadioButton tirebg3 = new JRadioButton();
static ButtonGroup tirebg = new ButtonGroup();
public static void main(String[] args) {
Car cspeed = new Car();
int carspeed = cspeed.getSpeed();
Motorcycle mspeed = new Motorcycle();
int motospeed = mspeed.getSpeed();
Truck tspeed = new Truck();
int truckSpeed = tspeed.getSpeed();
JRadioButton wide = new JRadioButton();
JLabel tbuttons = new JLabel();
JPanel topPane = new JPanel();
tirebg.add(tirebg1);
tirebg.add(tirebg2);
tirebg.add(tirebg3);
JFrame GUIframe = new JFrame();
JLabel label1 = new JLabel();
label1.setLayout(new FlowLayout());
JLabel tireLabel = new JLabel();
String[] names = new String[5];
names[0] = "Car";
names[1] = "Truck";
names[2] = "Motorcycle";
String[] hello = new String[5];
GUIframe.setSize(500, 500);
GUIframe.setDefaultCloseOperation(EXIT_ON_CLOSE);
JList list = new JList(names);
list.setBorder(BorderFactory.createRaisedSoftBevelBorder());
label1.add(list);
tireLabel.add(tirebg1);
tireLabel.add(tirebg2);
tireLabel.add(tirebg3);
topPane.add(tbuttons);
topPane.add(tireLabel);
topPane.setLayout(new FlowLayout());
label1.setBackground(Color.cyan);
GUIframe.add(topPane);
GUIframe.validate();
GUIframe.setBackground(Color.GREEN);
GUIframe.setVisible(true);
}
}
Since you posted a lot of code and I'm not sure what were you trying to achieve, I modified your code adding 3 JLabels at the topPane. And 3 JRadioButtons (I didn't add the ButtonGroup) below on a second JPanel, I commented how to make them appear on a vertical and horizontal align.
Something you should take into account is:
Don't extend and create objects from JFrame (One or the other, not both, I recommend you to create objects).
You were giving your JPanel a Layout after adding components to it, it should be done before.
From the above point, you were also giving your Layout to your JLabel not your JPanel.
You were adding a JList into a JLabel.
You missed to have a class constructor too.
Don't have multiple JFrames for more see The use of multiple JFrames, Good / Bad practice
Next time post a code which has no dependencies such as your Truck, Car and Motorcycle classes (i.e. a Runnable example). And use plain text instead so we can copy-paste the code and see the issue. Also try posting images (or the link and we can edit to add it).
Now, the outpus of my own program are:
And it was done with the following code.
import javax.swing.*;
import java.awt.*;
public class GUIExample {
JFrame frame;
JLabel label1, label2, label3;
JPanel topPane, radioPane;
JRadioButton radio1, radio2, radio3;
public static void main(String[] args) {
new GUIExample();
}
GUIExample () {
frame = new JFrame();
topPane = new JPanel();
radioPane = new JPanel();
topPane.setLayout(new FlowLayout());
// radioPane.setLayout(new BoxLayout(radioPane, BoxLayout.PAGE_AXIS)); //Vertical align
radioPane.setLayout(new FlowLayout()); //Horizontal align
label1 = new JLabel("Car");
label2 = new JLabel("Motorcycle");
label3 = new JLabel("Truck");
radio1 = new JRadioButton("Radio1");
radio2 = new JRadioButton("Radio2");
radio3 = new JRadioButton("Radio3");
topPane.add(label1);
topPane.add(label2);
topPane.add(label3);
radioPane.add(radio1);
radioPane.add(radio2);
radioPane.add(radio3);
frame.add(topPane, BorderLayout.PAGE_START);
frame.add(radioPane, BorderLayout.CENTER);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
}
Your code has several issues, but the reason that you're not seeing the tireLabel or the tbuttons component is because you're using a JLabel. Understand that JLabel is not built to act as a container for other components. The key concept is that it calculates its preferred size based on the text it holds and/or the icon it holds and (and this is key) not on the sizes or preferred sizes of any components it might hold.
The solution is to not use JLabel for a purpose it wasn't intended for but rather to use a JPanel which does adjust its own preferred size depending on the sizes of its held components and its layouts.
Other unrelated issues:
Your program extends JFrame but never uses itself as a JFrame, something that will confuse anyone who reads your code. If you're not going to use the instance of the class as a JFrame, then don't extend the class.
Your program isn't an OOP-compliant program, one with instance fields, public methods, and such, but rather is little more than one large static main method, and this will result in a large God-method, one with too much responsibility, and one that is very difficult to debug and to maintain. Don't throw out the OOP baby with the bath water -- Create Swing GUI's in a well-behaved OOP-compliant way.
You're trying to set background colors to components that are not opaque (a JLabel), to components that are never added to the GUI (label1), or are not fully displayed (the JFrame).
You're using FlowLayout an awful lot, and in places where other layouts would probably serve you better. It's as if it's the only layout that you know how to use, and so you use it. Try branching out and using other layouts including GridLayout for your JRadioButton container and perhaps BorderLayout for the main container (JPanel).
I am trying to use Java Swing to create a simple GUI in which I have a drawing pad and some buttons it all works fine until I add this code for the JTextField:
String text = "hello";
JTextArea textArea = new JTextArea(text);
textArea.setPreferredSize(new Dimension(500, 50));
textArea.setEditable(false);
Before adding this code the drawpad displays on the left of the screen followed by the buttons, when I add this only the drawpad is displayed unless I resize the frame in which case the buttons and text field reappear although the text field is hidden behind the drawpad slightly. Here is the full code:
public class testGUI extends Frame{
public static void main(String[] args) {
JFrame frame = new JFrame("Neural Networks");
frame.setSize(700, 300); //set the size of the frame
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true); //make it visible
Container content = frame.getContentPane();
content.setLayout(new BorderLayout());
JPanel mainPanel = new JPanel();
final PadDraw drawPad = new PadDraw();
drawPad.setSize(100, 100);
content.add(drawPad);
JButton clearButton = new JButton("Clear");
clearButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
drawPad.clear();
}
});
JButton loadButton = new JButton("Load");
loadButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
//Load something here
}
});
JButton testButton = new JButton("Test Draw Pad Image");
testButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
//
}
});
JButton loadImage = new JButton("Test image from file");
loadImage.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
//String filename = textField.getText();
}
});
String text = "hello";
JTextArea textArea = new JTextArea(text);
textArea.setPreferredSize(new Dimension(500, 50));
textArea.setEditable(false);
mainPanel.add(clearButton);
mainPanel.add(loadButton);
mainPanel.add(testButton);
mainPanel.add(loadImage);
mainPanel.add(textArea);
content.add(mainPanel);
}
}
You're adding the drawPad and the mainPanel to the content panel, which uses BorderLayout, without specifying any location. They thus end up both in the center position of the border layout, which is supposed to contain only one component.
See How to use BorderLayout in the Swing tutorial.
Also note that setting the preferred size is not something you should do. Instead, the preferred size is supposed to be automatically computed based on other sttings (the contained components, the number of rows and columns of a text area, etc.)
And a JTextArea should be enclosed into a JScrollPane to be good-looking and allow you to scroll.
JPanel mainPanel = new JPanel();
The default layout for a JPanel is a FlowLayout, so all the components flow on a single row. If there is not enough room on the row then the components wrap to the next row.
So when you add the JTextArea the flow is disturbed. The solution is to use a combination of layout managers to get your desired layout effect. Read the section from the Swing tutorial on Using Layout Managers for more information and examples.
JTextArea textArea = new JTextArea(text);
textArea.setPreferredSize(new Dimension(500, 50));
Also, you should NOT set the preferred size of the text area (or any Swing component for that matter). Instead you should do something like:
JTextArea textArea = new JTextArea(rows, columns);
and let the component determine its own preferred size. Also a text area is typically used with a JScrollPane and then you add the scroll pane to your panel:
JScrollPane scrollPane = new JScrollPane( textArea );
Edit:
Taking a second look at your code you have many more problems.
The point of using a layout manager is to have the layout manager set the size and location of the components. So your code should not have any logic related to the size/location of a component.
When you use the add(...) statement on a BorderLayout without a constraint, the component gets added to the CENTER. However only the last component added is managed by the BorderLayout. So only the "mainPanel" is given a size/location by the layout manager. That is why you need the setSize(...) statement on the drawPad to make the component visible. Although you now have the problem that two components are painted in the same space.
So to see the drawPad on the left you might want to use:
content.add(drawPad.BorderLayout.LINE_START);
However this still probably won't work because I'm guessing you are doing custom painting on the draw pad which means you will also need to override the getPreferredSize() method of the class so the layout manager can use the information to determine the size of the component. Read the section from the Swing tutorial on Custom Painting for more information and working examples.
Finally some other issues:.
The setVisible(...) statement should be invoked AFTER all the components have been added to the frame.
To follow Java standards, class names should start with an upper case character.
You should NOT be extending "Frame". There is no need to extend any class in your example.
Read the tutorial and download the demos for examples of better structured code.
Whenever I set the panel's Layout to FlowLayout, the JTable appears, however my imageBackground and buttons are misplaced. And when I set the layout to null, the the table doesn't appear, but the buttons and imageBackground are where I wanted them to be. What am I'm going to do with this?
public class AssetPanel extends JPanel implements ActionListener{
private ArrayList<AssetDetails> assetList;
private Frame frame;
private Database db;
private JTable assetTable;
private JScrollPane scrollPane;
private JButton btnBack;
private JButton btnView;
public AssetPanel (Frame frame){
super();
this.frame = frame;
initialize();
}
public void initialize(){
setName("Assets");
setSize(700, 475);
setLayout(null);
setVisible(true);
db = new Database();
btnView = new JButton("View");
btnView.addActionListener(this);
btnView.setBounds(450, 400, 90, 20);
add(btnView);
btnBack = new JButton("Back");
btnBack.setFont(new Font("Tahoma", Font.BOLD, 12));
btnBack.setBounds(550, 400, 90, 20);
btnBack.addActionListener(this);
add(btnBack);
ImageIcon imageBackground = new ImageIcon(AssetPanel.class.getResource("/resources/assets.png"));
JLabel jlBackground = new JLabel(imageBackground);
jlBackground.setBounds(0,0, 700, 475);
add(jlBackground);
initializeTable();
}
#Override
public void actionPerformed(ActionEvent ae) {
if(ae.getSource() == btnBack){
frame.changePanel("Main Menu");
}
}
public void initializeTable(){
Object[][] assetData;
assetList = new ArrayList<>();
String[] columnNames = {"Asset Name", "Date Acquired", "Type", "Classification"};
assetList = db.getAssetTable();
assetData = new Object[assetList.size()][columnNames.length];
for(int i = 0; i < assetList.size(); i++){
assetData[i][0] = assetList.get(i).getAssetName();
assetData[i][1] = assetList.get(i).getDateAcquired();
assetData[i][2] = assetList.get(i).getType();
assetData[i][3] = assetList.get(i).getClassification();
}
assetTable = new JTable(assetData, columnNames);
assetTable.setPreferredScrollableViewportSize(new Dimension(400, 100));
assetTable.setLocation(150, 100);
assetTable.setFillsViewportHeight(true);
scrollPane = new JScrollPane(assetTable);
add(scrollPane);
}
}
Don't use a null layout or use the setBounds() method to position and size components.
however my imageBackground and buttons are misplaced
A background is a Container component. That is you create it as a component and paint an image as the background. Then you add other components to the background component. Now the image will appear in the background and the other components appear on top of it.
See the Background Panel to give an example of creating a background component.
On possible solution: I recommend switching to Mig Layout as a solution to all java layout problems. I now use it for the layout of every single container component in my apps. If you switch you'll probably be glad you did (will never again have problems like that listed in this question).
http://www.miglayout.com/
MigLayout may be included in the JDK in a future version of java.
null layouts mean you have to explicitly place all the components.
I recommend BoxLayout. it's really simple, and you can put in spacers to create space between objects, and glue to fill in all remaining space.
you can also nest the boxes, as well.
if you look at java sample code (and at the source for things);
they nest a lot of JPanels to get the complicated layouts.
Try adding this before trying the steps below if it does not work:
// Set your flow layout thus:
setLayout(new FlowLayout(FlowLayout.LEFT,5,5));
// Set your table Auto Resize Mode to OFF
assetTable.setAutoResizeMode(assetTable.AUTO_RESIZE_OFF);
EXTRA: Try if above tips does not help
Technically, your class should extend a JFrame.
Add a root layout to the class(i.e. the JFrame):
setLayout(new FlowLayout(FlowLayout.LEFT,5,5));
Create two panels; one should contain your label and buttons components.
The other should contain the JScrollPane that contains your table.
Both panels can have their Layout which determines how the components will be laid out.
You can use FlowLayout.
Then you can add both panels to the mother layout (JFrame).
I have a GUI im building to illustrate a tree. The JPanel that I extended isnt showing the JLabel that I created when I constructed the JPanel. Here is my JPanel code:
class NodePanel extends JPanel {
private JLabel content;
NodePanel() {
this.setLayout(new FlowLayout());
this.setBorder(new LineBorder(Color.black));
}
NodePanel(String str) {
this.setLayout(new FlowLayout());
this.setBorder(new LineBorder(Color.black));
content = new JLabel(str);
this.add(content);
}
}
and here is the code where im testing it:
NodePanel n1 = new NodePanel(Integer.toString(root.getWeight()));
HuffmanGUI.tp.add(n1);
n1.setBounds((tpWidth / 2) - (panelDim / 2), vertSpace, panelDim, panelDim);
This code is in a method called by an action listener, I know it works because the panel shows up where its supposed to, but the Jlabel isnt displayed inside it. Why could this be?
Its hard to tell because we don't know the context of how the code is used. It looks like you are mixing null layouts with layout managers.
I might guess that you are adding the panel to a visible GUI and you haven't used revalidate() on the panel so the label doesn't have a size.
If you need more help then post your SSCCE that demonstrates the problem.