I'm building a Swing program and I want to be able to use a button to change certain features (Font, ForeGround Color, BackGround Color, etc.) of JComponents (JLabel, JButton).
I can do this without a problem if the components have all been explicitly declared and defined, but I cannot figure out how to do it if they are implicitly built using generic methods.
Below is the gist of what I have so far, minus some unimportant details. When styleButton1 and 2 are clicked, I want to refresh or rebuild the JFrame such that the new values for features/style (in this example, Font) are used for the components (testButton1 and 2), by changing currentFont and then repainting.
I'm not getting any errors with this, but frame and components are not being rebuilt/refreshed, i.e., nothing happens when the style buttons are clicked.
Any ideas on how to make this work? Or any other approaches I can use to get the desired effect?
//imports
public class GuiTesting extends JFrame {
public static void main(String[] args) {
frame = new GuiTesting();
frame.setVisible(true);
}
static JFrame frame;
static Font standardFont = new Font("Arial", Font.BOLD, 10);
static Font secondFont = new Font("Times New Roman", Font.PLAIN, 10);
static Font currentFont = standardFont;
public GuiTesting() {
setTitle("GUI Testing");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400, 400);
JPanel mainPanel = new JPanel();
getContentPane().add(mainPanel);
mainPanel.add(basicButton("Button1"));
mainPanel.add(basicButton("Button2"));
mainPanel.add(style1Button("Style 1"));
mainPanel.add(style2Button("Style 2"));
}
public static JButton basicButton(String title) {
JButton button = new JButton(title);
button.setPreferredSize(new Dimension(80, 30));
button.setFont(currentFont);
return button;
}
public static JButton style1Button(String title) {
JButton button = new JButton(title);
button.setPreferredSize(new Dimension(80, 30));
button.setFont(standardFont);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
currentFont = standardFont;
frame.repaint();
}
});
return button;
}
public static JButton style2Button(String title) {
JButton button = new JButton(title);
button.setPreferredSize(new Dimension(80, 30));
button.setFont(secondFont);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
currentFont = secondFont;
frame.repaint();
}
});
return button;
}
}
You can store components, which need to refresh style in a list :
private static List<JComponent> components = new ArrayList<JComponent>();
add then in your basicButton() method add new component to refreshing components:components.add(button);
And then in ActionListener you can execute next lines for refreshing style:
for(JComponent c : components){
c.setFont(currentFont);
}
Or you can pass components directly to ActionListener like next :
JButton b1;
JButton b2;
mainPanel.add(b1 = basicButton("Button1"));
mainPanel.add(b2 = basicButton("Button2"));
mainPanel.add(style1Button("Style 1",b1,b2));
and style1Button() code:
public static JButton style1Button(String title,final JComponent... components) {
JButton button = new JButton(title);
button.setPreferredSize(new Dimension(80, 30));
button.setFont(standardFont);
button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
currentFont = standardFont;
for(JComponent c : components){
c.setFont(currentFont);
}
frame.repaint();
}
});
return button;
}
Create a styleOne method in your JComponent class that sets all of the values you need. It will have access to all fields of your class. Inside the action listener call this method.
Also, don't create your buttons statically like that. Create them within the constructor directly. If you want to override the look of the buttons do it within an init method or constructor. Or, better yet, subclass JButton.
Related
I've hit a problem in getting a JPanel to update.
My simple program uses a custom JPanel which displays a label and a textfield. A Jbutton on the main panel is used to replace the JPanel with a new JPanel. The initial panel shows up fine but when the button is pressed the panel is not updated with a new MyPanel. I can tell that a new object is being created as count is being incremented.
public class SwingTest extends JFrame{
private JPanel mp;
private JPanel vp;
private JButton button;
public static void main(String[] args) {
SwingTest st = new SwingTest();
}
public SwingTest() {
vp = new MyPanel();
mp = new JPanel(new BorderLayout());
mp.add(vp, BorderLayout.CENTER);
button = new JButton("Change");
button.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent ae) {
vp = new MyPanel();
vp.revalidate();
}
});
mp.add(button, BorderLayout.SOUTH);
this.add(mp);
this.setDefaultCloseOperation(DISPOSE_ON_CLOSE);
setLocationRelativeTo(null);
setSize(250, 150);
pack();
setVisible(true);
}
}
and my custom panel....
public class MyPanel extends JPanel{
private JLabel label;
private JTextField tf;
static int count = 0;
public MyPanel(){
count++;
setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
setPreferredSize(new Dimension(400, 200));
c.gridx = 0;
c.gridy = 0;
label = new JLabel(String.valueOf(count));
tf = new JTextField(10);
add(label,c);
c.gridx = 1;
add(tf, c);
}
}
You state:
A Jbutton on the main panel is used to replace the JPanel with a new JPanel.
And yet this code:
button.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent ae) {
vp = new MyPanel();
vp.revalidate();
}
});
and yet this code does not do this at all. All it does is change the JPanel referenced by the vp variable, but has absolutely no effect on the JPanel that is being displayed by the GUI, which suggests that you're confusing reference variable with reference or object. To change the JPanel that is displayed, you must do exactly this: add the new JPanel into the container JPanel into the BorderLayout.CENTER (default) position, then call revalidate() and repaint() on the container.
e.g.,
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
// vp = new MyPanel();
// vp.revalidate();
mp.remove(vp); // remove the original MyPanel from the GUI
vp = new MyPanel(); // create a new one
mp.add(vp, BorderLayout.CENTER); // add it to the container
// ask the container to layout and display the new component
mp.revalidate();
mp.repaint();
}
});
Or better still -- use a CardLayout to swap views.
Or better still -- simply clear the value held by the JTextField.
For more on the distinction between reference variable and object, please check out Jon Skeet's answer to this question: What is the difference between a variable, object, and reference?
I want my buttons to print to the console when I click them. Here's my code. Im looking to make a basic app using this code, and I was wondering how to make the buttons have actions. For the first time, I just want to start with the console for the first time, but later possibly display images?
public static void main(String[] args) {
JFrame frame = new JFrame("GUI");
frame.setSize(320, 300);
frame.setBackground(Color.WHITE);
frame.setVisible(true);
JPanel panel = new JPanel();
panel.setSize(50,50);
JLabel label = new JLabel();
frame.add(panel);
panel.add(label);
label.setText("Welcome to Team 1389!");
Container contentPane = getContentPane();
contentPane.setBackground(Color.blue);
contentPane.setLayout(new FlowLayout());
JButton button = new JButton("MATCHES");
button.setSize(100, 30);
button.setLocation(95, 45);
button.addActionListener(null);
button.setVisible(true);
frame.add(button);
JButton button2 = new JButton("PIT TEAM");
button2.setSize(100, 30);
button2.setLocation(95, 100);
button2.setVisible(true);
frame.add(button2);
JButton button3 = new JButton("SCOUTING");
button3.setSize(100, 30);
button3.setLocation(95, 150);
button3.setVisible(true);
frame.add(button3);
}
private static Container getContentPane() {
// TODO Auto-generated method stub
return null;
}
}
You can look at this tutorial on Oracle's website, it explains things well:
Use an ActionListener. They are interfaces so you will need to add unimplemented methods where the event is handled:
button.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent event){
//do stuff..
}
});
You can also create the listener separately before adding it if you desire to do so:
ActionListener listener = new ActionListener(){
#Override
public void actionPerformed(ActionEvent event){
//do stuff..
}
};
button.addActionListener(listener);
I create two jbuttons in one panel(can be Box).i create same panel dynamically several times in same frame.so if two panels created dynamically those button make with same variable name.But i want to identify buttons one by one for put actions.how to identify dynamically created buttons one by one?
button creating code
public class Jscrollpanetest extends JFrame {
JScrollPane scrollPane;
Box box;
private static int panelCount = 0;
public Jscrollpanetest() {
setPreferredSize(new Dimension(200, 400));
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
scrollPane = new JScrollPane();
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
scrollPane.getVerticalScrollBar().setUnitIncrement(15);
box = Box.createVerticalBox();
scrollPane.getViewport().add(box);
this.add(scrollPane);
this.pack();
this.setLocationRelativeTo(null);
this.setVisible(true);
Timer t = new Timer(1000, new ActionListener() {
public void actionPerformed(ActionEvent ae) {
box.add(new TestPanel(), box.size());
scrollPane.validate();
}
});
t.setRepeats(true);
t.start();
}
public class TestPanel extends JPanel {
int myId = panelCount++;
public TestPanel() {
this.setLayout(new GridBagLayout());
this.setBorder(BorderFactory.createBevelBorder(1));
JButton up = new JButton("^");
JLabel rate = new JLabel("1");
JButton down = new JButton("^");
JLabel label = new JLabel("" + myId);
label.setHorizontalAlignment(JLabel.CENTER);
label.setVerticalAlignment(JLabel.CENTER);
this.setMaximumSize(new Dimension(1000, 200));
this.setPreferredSize(new Dimension(1000, 100));
this.add(label);
this.add(up);
this.add(rate);
this.add(down);
}
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
Jscrollpanetest testScrollPane = new Jscrollpanetest();
}
});
}
}
If use and dynamic created ActionListener there will be no problem. So each button will have its own ActionListener.
If using a common ActionListener must add tags to each button as extend JButton.
I am writing a very simple GUI, that contains 3 buttons, 2 labels, 2 text fields and one text area. Strangely, the result is unstable: when running the class the GUI appears with random number of the controls. I tried various layout managers, changing the order among the control - nothing.
Can someone help?
package finaltestrunner;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class FinalTestGUI extends JFrame implements ActionListener
{
public Boolean startState = false;
JButton sofButton;
JButton startStopButton;
JButton exitButton;
JTextField loopCounts;
JTextField trSnField;
JTextArea resultField = null;
public FinalTestGUI()
{
// The constructor creates the panel and places the controls
super(); // Jframe constructor
JFrame trFrame = new JFrame();
trFrame.setSize(1000, 100);
trFrame.setVisible(true);
trFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
trFrame.setTitle("Test runner");
setFont(new Font("SansSerif", Font.PLAIN, 14));
// trFrame.setLayout(new FlowLayout());
JPanel trControlPanel = new JPanel();
trControlPanel.setSize(1000, 100);
trControlPanel.setLayout(new GridLayout(1,7));
exitButton = new JButton("Exit");
trControlPanel.add(exitButton);
startStopButton = new JButton("Run ");
trControlPanel.add(startStopButton);
JLabel loopsLabel = new JLabel ("Loops count: ");
trControlPanel.add(loopsLabel);
loopCounts = new JTextField (5);
trControlPanel.add(loopCounts);
sofButton = new JButton("SoF");
trControlPanel.add(sofButton);
JLabel testLabel = new JLabel ("serial Number: ");
trControlPanel.add(testLabel);
trSnField = new JTextField (5);
trControlPanel.add(trSnField);
JTextArea trResultField = new JTextArea (80, 10);
trFrame.add(trControlPanel);
// cpl.add(trResultField);
startStopButton.addActionListener(new ActionListener()
{
#Override
public void actionPerformed (ActionEvent trStartStopButton)
{
startState = !startState;
if (startState)
{
startStopButton.setText("Run ");
startStopButton.setForeground(Color.red);
}
else
{
startStopButton.setText("Stop");
startStopButton.setForeground(Color.green);
}
}
});
sofButton.addActionListener(new ActionListener()
{
#Override
public void actionPerformed (ActionEvent trSofButton)
{
loopCounts.setText("SOF\n");
}
});
exitButton.addActionListener (new ActionListener()
{
#Override
public void actionPerformed (ActionEvent trExitButton)
{
System.exit(0);
}
});
} // End of the constructor
#Override
public void actionPerformed (ActionEvent ae) { }
public void atpManager ()
{
String selectedAtp = "";
}
}
There are a couple of issues with this code:
You are already inheriting from JFrame, so you do not need to create yet another JFrame
You are showing your frame with setVisible(true) and afterwards adding components to it. This invalidates your layout, you need to revalidate afterwards (or move setVisible() to a position where you already added your components)
You are adding your components to the JFrame directly, but you need to use its contentpane. Starting with Java 1.5, the JFrame.add() methods automatically forward to the content pane. In earlier versions, it was necessary to retrieve the content pane with JFrame.getContentPane() to add the child components to the content pane.
Try this:
public FinalTestGUI() {
// The constructor creates the panel and places the controls
super(); // Jframe constructor
setSize(1000, 100);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("Test runner");
setFont(new Font("SansSerif", Font.PLAIN, 14));
setLayout(new FlowLayout());
JPanel trControlPanel = new JPanel();
trControlPanel.setSize(1000, 100);
trControlPanel.setLayout(new GridLayout(1,7));
exitButton = new JButton("Exit");
trControlPanel.add(exitButton);
startStopButton = new JButton("Run ");
trControlPanel.add(startStopButton);
JLabel loopsLabel = new JLabel ("Loops count: ");
trControlPanel.add(loopsLabel);
loopCounts = new JTextField (5);
trControlPanel.add(loopCounts);
sofButton = new JButton("SoF");
trControlPanel.add(sofButton);
JLabel testLabel = new JLabel ("serial Number: ");
trControlPanel.add(testLabel);
trSnField = new JTextField (5);
trControlPanel.add(trSnField);
JTextArea trResultField = new JTextArea (80, 10);
// getContentPane().add(trControlPanel); // pre 1.5
add(trControlPanel); // 1.5 and greater
setVisible(true);
}
I am trying to get a JLabel to appear when a JButton is clicked. I have added an action listener and added the component to the layout. I am using the label1.setVisible(true) when the JButton is clicked in actionPerformed. I still can't get it work. Can some look at my code?
public class LearnAppMain extends JFrame implements ActionListener {
// Define variables
public JButton button1;
public JLabel label1;
public JTextField field1;
private Image image1;
private String apple = "apple.jpg";
public LearnAppMain() {
ImageIcon image1 = new ImageIcon(this.getClass().getResource(apple));
JLabel label1 = new JLabel(image1);
button1 = new JButton("A");
button1.addActionListener(this);
field1 = new JTextField(10);
// Create layout
setLayout(new FlowLayout());
// create Container
final Container cn = getContentPane();
cn.add(button1);
cn.add(field1);
cn.add(label1);
// setLayout(new FlowLayout());
setSize(250, 250);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (e.getSource() == button1) {
label1.setVisible(true);
field1.setText("Apple");
}
}
}
I have my main method in another class file. The error I get leads me to the label1.setVisible(true);
Every question I've seen they say to do this, but I'm wondering if there is something else that needs to be added.
There were a couple of issues here:
Your label1 was hidden by doing JLabel label in the constructor. You basically declared another variable called label1 in your constructor that hid the one in the class itself.
Your label was visible on the startup - I used label.setVisible(false) for the test, but you might want otherwise
I also put the creation of Image aside as I did not have an image, so uncomment that and change as appropriate.
Here's a complete working version:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class LearnAppMain extends JFrame implements ActionListener {
// Define variables
public JButton button1;
public JLabel label1;
public JTextField field1;
private Image image1;
private String apple = "apple.jpg";
public LearnAppMain() {
//ImageIcon image1 = new ImageIcon(this.getClass().getResource(apple));
//JLabel label1 = new JLabel(image1);
label1 = new JLabel("hello");
label1.setVisible(false);
button1 = new JButton("A");
button1.addActionListener(this);
field1 = new JTextField(10);
// Create layout
setLayout(new FlowLayout());
// create Container
final Container cn = getContentPane();
cn.add(button1);
cn.add(field1);
cn.add(label1);
// setLayout(new FlowLayout());
setSize(250, 250);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (e.getSource() == button1) {
label1.setVisible(true);
field1.setText("Apple");
}
}
public static void main(String[] args) {
new LearnAppMain();
}
}
I'd suggest using separate (usually inner-class) ActionListener instances instead of overriding actionPerformed. See e.g. this for a similar example if you are interested:
http://docs.oracle.com/javase/tutorial/displayCode.html?code=http://docs.oracle.com/javase/tutorial/uiswing/examples/events/BeeperProject/src/events/Beeper.java
Also, if you are using this in a bigger application (i.e. not just experimenting or for prototyping), make sure all Swing code is run on EDT.
You typically use SwingUtilities.invokeLater for that purpose.
Hope this helps.
first you don't add the image first itself to JLabel.
just create the object and leave it like..
ImageIcon image1 = new ImageIcon(this.getClass().getResource(apple));
JLabel label1 = new JLabel("");
label1.setVisible(true);
then do the modification in the action performed
public void actionPerformed(ActionEvent e) {
if (e.getSource() == button1)
{
field1.seticon(image1);
field1.revalidate();
}
it will definitely works
clientDetail.addActionListener(new ActionListener(){
public void actionPerformed (ActionEvent e){
d.getContentPane().removeAll();
g = new GridBagLayout();
gc = new GridBagConstraints();
d.setLayout(g);
JLabel message= new JLabel(" Message");
addComponent(message,5,1,1,2);
JTextArea Message = new JTextArea();
addComponent(Message,5,1,1,2);
d.setVisible(true);
d.setVisible(true);
d.pack();
}
private void addComponent(Component component, int i, int i0, int i1, int i2) {
gc.gridx=i;
gc.gridy=i0;
gc.gridheight=i1;
gc.gridwidth=i2;
g.setConstraints(component, gc);
add(component);
}
});
Recep.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
}
});