That's My Code Down Here. I want the answer for java.awt.Button and java.awt.Frame.
Can any one help me with it?
import java.awt.*;
import java.awt.event.*;
public class TestGUI extends Frame implements ActionListener, WindowListener{
private Label lbl;
private Label lbl1
private Label lbl2;
private Label lbl3;
private TextField tf;
private TextField tf1;
private TextField tf2;
private Button btn;
private Button btn1;
private Frame frame;
public TestGUI() {
setLayout(new FlowLayout());
lbl = new Label("Hi Guys! That's My First GUI Program and is made by me too");
add(lbl);
lbl1 = new Label("Enter Your Name Please ~");
add(lbl1);
tf1 = new TextField(30);
tf1.setEditable(true);
add(tf1);
lbl2 = new Label("Enter Your Age Please ~");
add(lbl2);
tf2 = new TextField(30);
tf2.setEditable(true);
add(tf2);
lbl3 = new Label("Enter Your School/College Name Please ~");
add(lbl3);
tf = new TextField(28);
tf.setEditable(true);
add(tf);
btn = new Button("Cancel");
add(btn);
btn.addActionListener(this);
addWindowListener(this);
setTitle("My own GUI");
setSize(500, 300);
setVisible(true);
}
public static void main(String[] args){
TestGUI app = new TestGUI();
}
#Override
public void actionPerformed(ActionEvent evt){
}
#Override
public void windowClosing(WindowEvent evt){
System.exit(0);
}
#Override public void windowDeactivated(WindowEvent evt){}
#Override public void windowActivated(WindowEvent evt){}
#Override public void windowOpened(WindowEvent evt){}
#Override public void windowClosed(WindowEvent evt){}
#Override public void windowIconified(WindowEvent evt){}
#Override public void windowDeiconified(WindowEvent evt){}
}
Thanks in Advance.
You're just complicating the things. Instead of extending the frame & implementing those interfaces, just extend JFrame.
public class TestGUI extends JFrame{...}
In your TestGUI frame create another JFrame say otherFrame and create two bottons say Open & Close and then bind ActionListener to them.
openBtn.addActionListener(new ActionListener(){
otherFrame.setVisible(true);
});
closeBtn.addActionListener(new ActionListener(){
otherFrame.setVisible(false);
});
The setVisible() method accepts boolean & this is what you actually need.
Much simpler & cleaner code.
It might make more sense for you to use a JFrame instead of a Frame (I recomend you read Kumar Vivek Mitra's answer here to get a better idea of why).
If you use a JFrame, you'll need to call yourJFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE) to stop your program when you close the window.
To respond to your button clicks, simply pass Anonymous Classes to your buttons addOnClickListener() method, like this:
btn.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//Do stuff here
}
});
Then you should be able to remove your existing actionPerformed() method.
For opening a new frame and closing your existing one, you should be creating two JFrame objects instead of extending Frame (or JFrame). Then, when you want to open your second frame, just call secondFrame.setVisable(true), and close your first one with firstFrame.dispose. However, I'd have a look at JDialogs and JOptionPanes first to see if they might work better for you.
After all this you should be able to remove all your WindowListener stuff, as that's for something slightly different. (Have a look here if you're interested)
Finally, don't forget to add a semicolon after your lbl1 label. ;)
Good luck!
You may use ActionListener interface.
However for a little addition to above guys commented. You may add animation to your frame by adding for loop and setSize method within the loop and the height width of the corresponding loop's variable.
Related
In my program, I have this MAIN window and a HELP window. The HELP window (when opened) is to always stay on top whether it's in focus or not. The issue however is, when I try to requestFocusInWindow() for a component in the MAIN window through an action listener that gets fired from the HELP window, it just won't let me do it.
What is the proper way of accomplishing this?
TY :)
Edit:
As requested, here's a short example of what I'm trying to accomplish. Essentially I need the button inside the HELP window to trigger focus to the TextField inside the Main window.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Main {
public static void initGUI() {
mainFrame = new JFrame("Main");
helpFrame = new JFrame("Help");
mainFrame.setPreferredSize(new Dimension(500, 200));
helpFrame.setPreferredSize(new Dimension(500, 200));
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
helpFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainFrame.setLayout(new FlowLayout());
helpFrame.setLayout(new FlowLayout());
mainTextView = new JTextField("", 20);
mainButton = new JButton("Open Help");
helpButton = new JButton("Request Focus");
mainButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource().equals(mainButton)) {
helpFrame.pack();
helpFrame.setVisible(true);
}
}
});
helpButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource().equals(helpButton))
System.out.println("Focus requested:" + mainTextView.requestFocusInWindow());
}
});
helpFrame.add(helpButton);
mainFrame.add(mainTextView);
mainFrame.add(mainButton);
mainFrame.pack();
mainFrame.setVisible(true);
}
public static void main(String[] args) {
initGUI();
}
static JFrame mainFrame, helpFrame;
static JTextField mainTextView;
static JButton mainButton, helpButton;
}
So turns out the fix was rather trivial. If requestFocus() is used instead of requestFocusInWindow(), it seems to work just fine.
Kinda feel stupid for how much time I spent on this :P
helpButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource().equals(helpButton))
mainTextView.requestFocus();
}
});
Ok so I have 2 jPanels.
one of them has a number of buttons that when pressed should add text to the the textfield that is in the second jPanel.
I am brand spanking new to swing with previously only having to write back end code and web based code so I am having difficulty seeing how you would accomplish this.
I only have buttons created in one panel and a textfield in another so i suspect code would be irrelevant.
Any articles that someone could point me to or examples are greatly appreciated.
So I had this problem ones,
So Lets say you have two JFrame JFrame1 and JFrame2
In order to communicate with each other at runtime both has to have most recent initialized object of each individual frame.
Now lets say this is your first frame where is your textbox,
public class JFrame1 extends JFrame{
JTextField jTextField= null;
public JFrame1() throws HeadlessException {
super("JFrame");
setSize(200, 200);
jTextField = new JTextField();
add(jTextField);
setVisible(true);
}
public void setValueToText(String value){
jTextField.setText(value);
}
}
Then This is second and where is your Button,
public class JFrame2 extends JFrame{
JButton jButton= null;
JFrame1 frame1=null;
public JFrame2() throws HeadlessException {
super("JFrame");
frame1=new JFrame1();
jButton = new JButton("Clieck Me");
add(jButton);
setVisible(true);
jButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
frame1.setValueToText("Hi");
}
});
setVisible(true);
}
public static void main(String[] args) {
JFrame2 jf= new JFrame2();
jf.setSize(200, 200);
}
}
Now Just run second class file and click one button which will set hi on your textbox which is in second frame.
So As you see answer lay's in Initialized second object in frame.
My execution is like,
Run JFrame2
Initialized JFrame1 in JFame2 const.
you can make the JTextField an instance variable of the enclosing JFrame and make the two panels inner classes of it. By this, the two panels will have a reference to the same field which belongs to the outer class.
So, you will end up having something similar to:
public class Outer extends JFrame{
private JTextField text = new JTextField();
...
public Outer(){
this.add(new Inner1(), BorderLayout.NORTH);
this.add(new Inner2(), BorderLayout.SOUTH);
}
class Inner1 extends JPanel{
...
public Inner1(){
this.add(text);
}
}
class Inner2 extends JPanel implements ActionListener{
private JButton button = new JButton();
public Inner2(){
button.addActionListener(this);
}
public void actionPerformed(ActionEvent e){
if (e.getSource() == button)
text.setText("Hello StackOverFlow");
}
}
}
add your code to change the text in another panel, when a button clicked in the first panel.
mybutton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//do your logic to change the text in another panel
}
});
I wrote a program for an applet that is supposed to display different text in a text box when you push a button. My program has no errors when I compiled it, but the text box doesn't display correctly. I don't know what is wrong with it. Here is my code
import java.awt.*;
import java.awt.event.*;
public class colors{
Button button1;
Button button2;
Button button3;
Label label1;
TextField objTextField1;
public static void main (String args[]){
colors c = new colors();
}
public colors() {
Frame f = new Frame ("Colors");
Button button1 = new Button("Blue");
button1.setBounds(10,305,120,75);
button1.addMouseListener(new MyMouseListener1());
Button button2 = new Button("Red");
button2.setBounds(140,305,120,75);
button2.addMouseListener(new MyMouseListener2());
Button button3 = new Button("Yellow");
button3.setBounds(270,305,120,75);
button3.addMouseListener(new MyMouseListener3());
f.add(button1);
f.add(button2);
f.add(button3);
label1 = new Label("Click a Button to Reveal Text");
label1.setBounds(20,105,200,25);
f.add(label1);
objTextField1 = new TextField("Which Color?", 15);
objTextField1.setBounds(20,75,125,50);
f.add(objTextField1);
f.add(label1);
f.add(objTextField1);
f.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent we){
System.exit(0);
}
});
f.setSize(400,400);
f.setVisible(true);
}
public class MyMouseListener1 extends MouseAdapter{
public void mouseClicked(MouseEvent me){
objTextField1.setText("Blue");
}
}
public class MyMouseListener2 extends MouseAdapter{
public void mouseClicked(MouseEvent me){
objTextField1.setText("Red");
}
}
public class MyMouseListener3 extends MouseAdapter{
public void mouseClicked(MouseEvent me){
objTextField1.setText("Yellow");
}
}
}
When a Button is clicked it fires an ActionEvent.
You should use an ActionListener instead of a MouseListener.
public void actionPerformed(ActionEvent e) {
...//code that reacts to the action...
}
AND don't forget to add
button.addActionListener(instance);
I have tested your code and it's working as expected but I have noticed some of the points in your code as mentioned below:
Use setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE) instead of System.exit(0) and adding WindowListener to close the window.
Use frame.pack() instead of frame.setSize() that fits the components as per component's preferred size.
Don't use null layout and never use absolute positioning via calling setBounds() instead use a proper Layout Manager that suits as per your application design.
Read more How to Use Various Layout Managers
Use SwingUtilities.invokeLater() or EventQueue.invokeLater() to make sure that EDT is initialized properly.
Read more
Why to use SwingUtilities.invokeLater in main method?
SwingUtilities.invokeLater
Should we use EventQueue.invokeLater for any GUI update in a Java desktop application?
Follow Java Naming convention
Keep the instance members private
This is already addressed by #TAsk that you should be using ActionListener instead of MouseListener if you are interested in only mouseClicked() method.
You should be using Swing components instead of AWT components as already mentioned by #peeskillet
To make an applet you should extend javax.swing.JApplet class & override init() method.
To change the color, you must write your logics in actionPerformed() of ActionListener. But it's an interface. So, you can make use of Anonymous Inner class & implement actionPerformed() in it.
So, when you call addActionListener() on a JButton, I recommend you to do that by using Anonymous Inner class. It would be more clear through following code.
My Suggestion: Whenever you write code, always keep OOD principles in your mind. This isn't right place to discuss that, but your code has a Code smell which is Duplication in code.
Below is the best way to do what you want & we're also using DRY Principle.
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
public class ColorChanger extends javax.swing.JApplet {
private JPanel mainPanel;
private JButton btnRed;
private JButton btnGreen;
private JButton btnBlue;
#Override
public void init() {
super.init();
mainPanel = new JPanel();
btnRed = new JButton("Red");
btnGreen = new JButton("Green");
btnBlue = new JButton("Blue");
this.add(mainPanel);
mainPanel.add(btnRed);
mainPanel.add(btnGreen);
mainPanel.add(btnBlue);
bindActionEvent(btnRed, Color.RED);
bindActionEvent(btnGreen, Color.GREEN);
bindActionEvent(btnBlue, Color.BLUE);
}
private void bindActionEvent(JButton b1, Color color) {
b1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
mainPanel.setBackground(color);
//Write setText() for your TextField here.
}
});
} //END Of Helper Method
}
I have a frame and a panel.Permanently I remove the panel and add another panel.After adding a new panel I need the JTextField to get focused.How can I do this?
I tried panel.requestFocus() method but it didnt work.
Example Code:
public class Test{
public static void main(String[] args){
JFrame frame = new JFrame();
// ... frame options
// MyPanel extends JPanel
// and has a JTextField
contentPane.add(new MyPanel());
// Permanently I need to add another panel
contentPane.removeAll();
contentPane.add(new MyPanel());
}
}
Calling panel.requestFocus() attempts to give focus to the container itself rather than on any of its child components.
Use requestFocusInWindow on the JTextField after the component has been added to the JFrame. Add an public method in MyPanel for calling this method.
Avoid using requestFocus. From the docs:
requestFocus, is discouraged because it tries to give the focus to the component's window, which is not always possible. As of JDK 1.4, you should instead use the requestFocusInWindow method, which does not attempt to make the component's window focused.
public class Test {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame("Focus JTextField");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
MyPanel myPanel = new MyPanel();
frame.add(myPanel);
frame.setVisible(true);
frame.pack();
myPanel.focusTextField();
}
});
}
}
class MyPanel extends JPanel {
private JTextField textField;
public MyPanel() {
textField = new JTextField(20);
add(textField);
}
public void focusTextField() {
textField.requestFocusInWindow();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(300, 100);
}
}
Add a method like this to MyPanel:
public void gainFocus() {
tf.requestFocus();
}
Call it from the main method, or elsewhere whenever you need it to be focused.
Use. textfield.setText(""); when you need to get the focus or try something like you will take your control to your field try
You will need a method either to get the TextField from MyPanel, like getTextField, or a method to just directly focus on the TextField. These methods must be inside your MyPanel class.
Example method:
public class MyPanel extends JPanel {
private JTextField textField;
//your code here
public void getTextFieldFocus() {
textField.requestFocus();
}
}
Then you call this getTextFieldFocus method when you need to focus.
Else, if you extract the TextField from the MyPanel class using a getTextField method, you call this when you need the focus:
panel.getTextField().requestFocus();
I have two JFrames. The first one is defined as public firstJframe and the second one is defined as public static final jFrame. I want to open the second JFrame on clicking a button on the first JFrame. How can I do this?
.setVisible does not work for this. I really don't know how to proceed with this.
Try calling revalidate() for the object you want to update(in your case the second frame).
Example:
JButton myButton = new JButton("Open new window");
JFrame newFrame = new JFrame("New Window");
myButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
newFrame.pack();
newFrame.setVisible(true);
newFrame.revalidate();
}
});
Update
If that does not work, try calling this:
newFrame.invalidate();
newFrame.validate();
I propose:
under the button type:
this.dispose
new public static final jFrame.setvisible(true);