We Keep Coding

Determining the sequence of two clicks a user makes

public class GlassActionListener{
JButton first;
JButton second;
#Override
public void actionPerformed(ActionEvent e) {
if(first == null)
{
first = (JButton) e.getSource();
}
else
{
second = (JButton) e.getSource();
// do something
// clean up
first = null;
second = null;
}
}
}
public class GUIControl {
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
showGUI();
}
});
}
public static void showGUI() {
JFrame frame = new JFrame("MyFrame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
JButton glass1 = new JButton("glass1");
JButton glass2 = new JButton("glass2");
JButton glass3 = new JButton("glass3");
frame.getContentPane().add(glass1);
frame.getContentPane().add(glass2);
frame.getContentPane().add(glass3);
frame.pack();
frame.setVisible(true);
glass1.addActionListener(??);
glass2.addActionListener(??);
glass3.addActionListener(??);
// I want to store the first two clicks in these variables
from = "glassX";
to = "glassY";
puzzle.move(from, to);
}
The user will spill soda between the glasses. The first JButton the user clicks out of the three available determines the "from" initial glass and the second JButton the user clicks out of the three available determines the "to" destination glass.
How can I determine the specific two JButtons that the user clicked?
Everytime the user clicks two out of the three JButtons I want to store the string associated with those two JButtons in a "from" and "to" variable.
Is there any way to do this?

make an ActionListener and use JButton#addActionListener to add it to all three buttons. The event has a source field you can use.
ActionListener listener = new ActionListener() {
JButton first;
JButton second;
#Override
public void actionPerformed(ActionEvent e) {
if(first == null)
{
first = (JButton) e.getSource();
}
else
{
second = (JButton) e.getSource();
// do something
// clean up
first = null;
second = null;
}
}
};
glass1.addActionListener(listener);
glass2.addActionListener(listener);
glass3.addActionListener(listener);
Handling the logic inside the listener is a little dirty, but that's the idea.

firstbutton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//do something here first button is clicked
}
} );
you can add listeners to buttons like this.and use a class variable to track how many times the buttons are clicked.
eg:
public class GUIControl {
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
showGUI();
}
});
}
public static void showGUI() {
JFrame frame = new JFrame("MyFrame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
JButton glass1 = new JButton("glass1");
JButton glass2 = new JButton("glass2");
JButton glass3 = new JButton("glass3");
String from = "";
String to = "";
int click_count = 0;
glass1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(click_count ==0)
{
from = "glassX";
click_count = 1;
}else if(click_count ==1)
{
from = "glassY";
click_count = 0;
}
}
} );
glass2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(click_count ==0)
{
from = "glassX";
click_count = 1;
}else if(click_count ==1)
{
from = "glassY";
click_count = 0;
}
}
} );
glass3.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(click_count ==0)
{
from = "glassX";
click_count = 1;
}else if(click_count ==1)
{
from = "glassY";
click_count = 0;
}
}
} );
frame.getContentPane().add(glass1);
frame.getContentPane().add(glass2);
frame.getContentPane().add(glass3);
frame.pack();
frame.setVisible(true);
// I want to store the first two clicks in these variables
}

Can you make a JToolBar undetachable?

I would like to make my JToolBar impossible to detach from its container but still let the user drag it to one of the container's sides.
I know about
public void setFloatable( boolean b )
but this won't allow the user to move the JToolBar at all.
Is there any way of doing this without overwriting ToolBarUI?
Also, is there an option to highlight its new position before dropping it?

It's not the most elegant solution, but it works.
public class Example extends JFrame {
BasicToolBarUI ui;
Example() {
JToolBar tb = new JToolBar();
tb.add(new JButton("AAAAA"));
tb.setBackground(Color.GREEN);
ui = (BasicToolBarUI) tb.getUI();
getContentPane().addContainerListener(new Listener());
getContentPane().add(tb, BorderLayout.PAGE_START);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(300, 300);
setLocationRelativeTo(null);
setVisible(true);
}
class Listener implements ContainerListener {
#Override
public void componentAdded(ContainerEvent e) {}
#Override
public void componentRemoved(ContainerEvent e) {
if (ui.isFloating()) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
ui.setFloating(false, null);
}
});
}
}
}
public static void main(String[] args) {
new Example();
}
}
Explanation:
Whenever the toolbar is moving to a floating state, it is instructed not do so. The only problem is that you have to wait for the EDT to finish the process for creating the floating window, and only then can you tell it not to float. The result is that you actually see the window created and then hidden.
Note:
I think that overriding the UI for the toolbar is a better solution, though it's possible that with a more intricate approach doing something similar to what I did will also work well.

works for me quite correctly on WinOS, old code from SunForum
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class CaptiveToolBar {
private Robot robot;
private JDialog dialog;
private JFrame frame;
public static void main(String[] args) {
//JFrame.setDefaultLookAndFeelDecorated(true);
//JDialog.setDefaultLookAndFeelDecorated(true);
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new CaptiveToolBar().makeUI();
}
});
}
public void makeUI() {
try {
robot = new Robot();
} catch (AWTException ex) {
ex.printStackTrace();
}
final JToolBar toolBar = new JToolBar();
for (int i = 0; i < 3; i++) {
toolBar.add(new JButton("" + i));
}
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 400);
frame.setLocationRelativeTo(null);
frame.add(toolBar, BorderLayout.NORTH);
final ComponentListener dialogListener = new ComponentAdapter() {
#Override
public void componentMoved(ComponentEvent e) {
dialog = (JDialog) e.getSource();
setLocations(false);
}
};
toolBar.addHierarchyListener(new HierarchyListener() {
#Override
public void hierarchyChanged(HierarchyEvent e) {
Window window = SwingUtilities.getWindowAncestor(toolBar);
if (window instanceof JDialog) {
boolean listenerAdded = false;
for (ComponentListener listener : window.getComponentListeners()) {
if (listener == dialogListener) {
listenerAdded = true;
break;
}
}
if (!listenerAdded) {
window.addComponentListener(dialogListener);
}
}
}
});
frame.addComponentListener(new ComponentAdapter() {
#Override
public void componentMoved(ComponentEvent e) {
if (dialog != null && dialog.isShowing()) {
setLocations(true);
}
}
});
frame.setVisible(true);
}
private void setLocations(boolean moveDialog) {
int dialogX = dialog.getX();
int dialogY = dialog.getY();
int dialogW = dialog.getWidth();
int dialogH = dialog.getHeight();
int frameX = frame.getX();
int frameY = frame.getY();
int frameW = frame.getWidth();
int frameH = frame.getHeight();
boolean needToMove = false;
if (dialogX < frameX) {
dialogX = frameX;
needToMove = true;
}
if (dialogY < frameY) {
dialogY = frameY;
needToMove = true;
}
if (dialogX + dialogW > frameX + frameW) {
dialogX = frameX + frameW - dialogW;
needToMove = true;
}
if (dialogY + dialogH > frameY + frameH) {
dialogY = frameY + frameH - dialogH;
needToMove = true;
}
if (needToMove) {
if (!moveDialog && robot != null) {
robot.mouseRelease(InputEvent.BUTTON1_MASK);
}
dialog.setLocation(dialogX, dialogY);
}
}
}

Keeping a JList selection after JList has lost focus?

I'm trying to create a form with a JList and a button
What I want to do, is select an item from the JList, and then press the button to perform an action dependant on the selection. However, as soon as the button is clicked, the JList loses focus, and the selection disappears, making the button unable to determine what element was selected in the JList.
Is there a solution to this?
Thanks in advance :)

I can't see any issue with example from Oracle JList tutorial
have look at ListSelectionListener
maybe carefully with SelectionModes
can you please to describe whats is your goal
code example
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class ListDemo extends JPanel implements ListSelectionListener {
private JList list;
private DefaultListModel listModel;
private static final String hireString = "Hire";
private static final String fireString = "Fire";
private JButton fireButton;
private JTextField employeeName;
public ListDemo() {
super(new BorderLayout());
listModel = new DefaultListModel();
listModel.addElement("Jane Doe");
listModel.addElement("John Smith");
listModel.addElement("Kathy Green");
list = new JList(listModel);
list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
list.setSelectedIndex(0);
list.addListSelectionListener(this);
list.setVisibleRowCount(5);
JScrollPane listScrollPane = new JScrollPane(list);
JButton hireButton = new JButton(hireString);
HireListener hireListener = new HireListener(hireButton);
hireButton.setActionCommand(hireString);
hireButton.addActionListener(hireListener);
hireButton.setEnabled(false);
fireButton = new JButton(fireString);
fireButton.setActionCommand(fireString);
fireButton.addActionListener(new FireListener());
employeeName = new JTextField(10);
employeeName.addActionListener(hireListener);
employeeName.getDocument().addDocumentListener(hireListener);
String name = listModel.getElementAt(list.getSelectedIndex()).toString();
JPanel buttonPane = new JPanel();
buttonPane.setLayout(new BoxLayout(buttonPane, BoxLayout.LINE_AXIS));
buttonPane.add(fireButton);
buttonPane.add(Box.createHorizontalStrut(5));
buttonPane.add(new JSeparator(SwingConstants.VERTICAL));
buttonPane.add(Box.createHorizontalStrut(5));
buttonPane.add(employeeName);
buttonPane.add(hireButton);
buttonPane.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
add(listScrollPane, BorderLayout.CENTER);
add(buttonPane, BorderLayout.PAGE_END);
}
class FireListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
int index = list.getSelectedIndex();
listModel.remove(index);
int size = listModel.getSize();
if (size == 0) { //Nobody's left, disable firing.
fireButton.setEnabled(false);
} else { //Select an index.
if (index == listModel.getSize()) {
index--;
}
list.setSelectedIndex(index);
list.ensureIndexIsVisible(index);
}
}
}
class HireListener implements ActionListener, DocumentListener {
private boolean alreadyEnabled = false;
private JButton button;
public HireListener(JButton button) {
this.button = button;
}
public void actionPerformed(ActionEvent e) {
String name = employeeName.getText();
if (name.equals("") || alreadyInList(name)) {
Toolkit.getDefaultToolkit().beep();
employeeName.requestFocusInWindow();
employeeName.selectAll();
return;
}
int index = list.getSelectedIndex(); //get selected index
if (index == -1) { //no selection, so insert at beginning
index = 0;
} else { //add after the selected item
index++;
}
listModel.insertElementAt(employeeName.getText(), index);
//listModel.addElement(employeeName.getText());
employeeName.requestFocusInWindow();
employeeName.setText("");
list.setSelectedIndex(index);
list.ensureIndexIsVisible(index);
}
protected boolean alreadyInList(String name) {
return listModel.contains(name);
}
public void insertUpdate(DocumentEvent e) {
enableButton();
}
public void removeUpdate(DocumentEvent e) {
handleEmptyTextField(e);
}
public void changedUpdate(DocumentEvent e) {
if (!handleEmptyTextField(e)) {
enableButton();
}
}
private void enableButton() {
if (!alreadyEnabled) {
button.setEnabled(true);
}
}
private boolean handleEmptyTextField(DocumentEvent e) {
if (e.getDocument().getLength() <= 0) {
button.setEnabled(false);
alreadyEnabled = false;
return true;
}
return false;
}
}
public void valueChanged(ListSelectionEvent e) {
if (e.getValueIsAdjusting() == false) {
if (list.getSelectedIndex() == -1) {
fireButton.setEnabled(false);
} else {
fireButton.setEnabled(true);
}
}
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("ListDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JComponent newContentPane = new ListDemo();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}

Just have a field that you update every time a selection is made. You could do this by adding a listener on your JList.
private class selectListener extends MouseAdapter {
public void mouseClicked(MouseEvent e) {
if (SwingUtilities.isLeftMouseButton(e)) {
currentSelected = list.getSelectedIndex();
}
}
}
Then use that field when your button is pressed.

Generate a double click mouse event in Java Swing

I am trying to generate a double click mouse event on the EDT as follows:
SwingUtilities.invokeLater(new Runnable() {
public void run() {
component.dispatchEvent(new MouseEvent(
component,
MouseEvent.MOUSE_CLICKED,
System.currentTimeMillis(),
InputEvent.BUTTON1_MASK,
x, y,
2, // click count
false
));
}
});
This does not seem to dispatch a double click event, even though I am setting the click count to 2.
Any suggestions or examples?

Considering:
final JButton clickTwiceButton = new JButton();
final JButton fireEventButton = new JButton();
Listeners:
clickTwiceButton.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(java.awt.event.MouseEvent evt) {
if (evt.getClickCount() == 2) {
JOptionPane.showMessageDialog(null, "Double clicked!");
}
}
});
fireEventButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
// Invoking later for no reason, just to simulate your code
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
clickTwiceButton.dispatchEvent(new MouseEvent(
fireEventButton,
MouseEvent.MOUSE_CLICKED,
1,
MouseEvent.BUTTON1,
0, 0,
2,
false
));
}
});
}
});
When I click fireEventButton the MouseEvent gets correctly dispatched to clickTwiceButton, and the dialog appears as expected.
So, as #Andrew pointed out, the problem seems to be that either you are firing the event to the wrong component or that something is not right with the registered MouseListener / MouseAdapter code.
Use component.getMouseListeners() to check for your component Listeners and debug the code that handles its events.

The method is very simple. You should get the time of the first click and the time of the second click, then you can do a condition in between.
Method code as below:
private boolean state=false;
private long first_pressed;
JButton btnAdd = new JButton("add");
btnAdd.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
if(state==false) {
first_pressed=e.getWhen();
state=true;
}
if(first_pressed!=e.getWhen())
{
JOptionPane.showConfirmDialog(null,"doubel click","Click",JOptionPane.YES_NO_OPTION);
state=false;
}
}
});

public class TestMouseListener implements MouseListener {
private boolean leftClick;
private int clickCount;
private boolean doubleClick;
private boolean tripleClick;
public void mouseClicked(MouseEvent evt) {
if (evt.getButton()==MouseEvent.BUTTON1){
leftClick = true; clickCount = 0;
if(evt.getClickCount() == 2) doubleClick=true;
if(evt.getClickCount() == 3){
doubleClick = false;
tripleClick = true;
}
Integer timerinterval = (Integer)Toolkit.getDefaultToolkit().getDesktopProperty("awt.multiClickInterval");
Timer timer = new Timer(timerinterval, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
if(doubleClick){
System.out.println("double click.");
clickCount++;
if(clickCount == 2){
doubleClick(); //your doubleClick method
clickCount=0;
doubleClick = false;
leftClick = false;
}
}else if (tripleClick) {
System.out.println("Triple Click.");
clickCount++;
if(clickCount == 3) {
tripleClick(); //your tripleClick method
clickCount=0;
tripleClick = false;
leftClick = false;
}
} else if(leftClick) {
System.out.println("single click.");
leftClick = false;
}
}
});
timer.setRepeats(false);
timer.start();
if(evt.getID()==MouseEvent.MOUSE_RELEASED) timer.stop();
}
}
public static void main(String[] argv) throws Exception {
JTextField component = new JTextField();
component.addMouseListener(new TestMouseListener());
JFrame f = new JFrame();
f.add(component);
f.setSize(300, 300);
f.setVisible(true);
component.addMouseListener(new TestMouseListener());
}
}

Distinguish between a single click and a double click in Java

I search the forum and see this codes:
public void mouseClicked(MouseEvent e) {
if (e.getClickCount() == 2) {
System.out.println(" and it's a double click!");
wasDoubleClick = true;
} else {
Integer timerinterval = (Integer) Toolkit.getDefaultToolkit().getDesktopProperty(
"awt.multiClickInterval");
timer = new Timer(timerinterval.intValue(), new ActionListener() {
public void actionPerformed(ActionEvent evt) {
if (wasDoubleClick) {
wasDoubleClick = false; // reset flag
} else {
System.out.println(" and it's a simple click!");
}
}
});
timer.setRepeats(false);
timer.start();
}
}
but the code runs incorrectly(Sometime it prints out " and it's a single click!" 2 times . It should print out " and it's a double click!"). Can anybody show me why? or can you give me some better ways to do this?
Thank you!

Sometime it prints out " and it's a single click!" 2 times . It should print out " and it's a double click!").
That is normal. A double click only happens if you click twice within the specified time interval. So sometimes if you don't click fast enough you will get two single clicks in a row.
Integer timerinterval = (Integer) Toolkit.getDefaultToolkit().getDesktopProperty("awt.multiClickInterval");
The above line of code determines how fast the double click must be.
For what its worth here is some code I have used to do the same thing. Don't know if its any better or worse than the code you have:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class ClickListener extends MouseAdapter implements ActionListener
{
private final static int clickInterval = (Integer)Toolkit.getDefaultToolkit().
getDesktopProperty("awt.multiClickInterval");
MouseEvent lastEvent;
Timer timer;
public ClickListener()
{
this(clickInterval);
}
public ClickListener(int delay)
{
timer = new Timer( delay, this);
}
public void mouseClicked (MouseEvent e)
{
if (e.getClickCount() > 2) return;
lastEvent = e;
if (timer.isRunning())
{
timer.stop();
doubleClick( lastEvent );
}
else
{
timer.restart();
}
}
public void actionPerformed(ActionEvent e)
{
timer.stop();
singleClick( lastEvent );
}
public void singleClick(MouseEvent e) {}
public void doubleClick(MouseEvent e) {}
public static void main(String[] args)
{
JFrame frame = new JFrame( "Double Click Test" );
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.addMouseListener( new ClickListener()
{
public void singleClick(MouseEvent e)
{
System.out.println("single");
}
public void doubleClick(MouseEvent e)
{
System.out.println("double");
}
});
frame.setSize(200, 200);
frame.setVisible(true);
}
}

public void mouseClicked(MouseEvent evt) {
if (evt.getButton()==MouseEvent.BUTTON1){
leftClick = true; clickCount = 0;
if(evt.getClickCount() == 2) doubleClick=true;
Integer timerinterval = (Integer)Toolkit.getDefaultToolkit().getDesktopProperty("awt.multiClickInterval");
timer = new Timer(timerinterval, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
if(doubleClick){
System.out.println("double click.");
sb = new StringBuffer();
sb.append("Double Click");
clickCount++;
if(clickCount == 2){
clickCount=0;
doubleClick = false;
}
} else {
sb = new StringBuffer();
sb.append("Left Mouse");
System.out.println("single click.");
}
}
});
timer.setRepeats(false);
timer.start();
if(evt.getID()==MouseEvent.MOUSE_RELEASED) timer.stop();
}