I've added a keylistener to my JTextArea field, but it doesn't behave as I expected.
inputTextArea.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent k) {
//If the return button is hit, only set to a new line if shift is also down.
if(k.getKeyChar() == KeyEvent.VK_ENTER) {
if(k.isShiftDown()) {
inputTextArea.append(" \n");
} else {
//Send The Message...
boolean cleanTextField = false;
try {
sendMessage(inputTextArea.getText());
cleanTextField = true;
msgScrollPane.setAutoscrolls(true);
JScrollBar vbar = msgScrollPane.getVerticalScrollBar();
if ((vbar.getValue() + vbar.getVisibleAmount()) == vbar.getMaximum()) {
msgPane.setCaretPosition(msgDoc.getLength());
}
} catch (Exception ex) {
ex.printStackTrace();
cleanTextField = false;
} finally {
if(cleanTextField) {
inputTextArea.setText("");
}
}
}
}
}
});
I want this:
- If the return button is hit and shift is down: add a new line.
- If the return button is hit and the shift button isn't down: no new line, but submit.
Now it behaves like this:
- If I hit the return button and shift is down: no line added. Nothing happens.
- If I hit the return button and shift isn't down: submitted, but if I start typing again it begins on new line.
Does someone know how to do what I want?
EDIT:
I tried some other code to detect if the shift button is down:
if((k.getModifiersEx() == KeyEvent.SHIFT_DOWN_MASK) ||
(k.getModifiers() == KeyEvent.SHIFT_DOWN_MASK)) {
This doesn't work as well
You may use the InputMap and ActionMap of the JTextArea to map the key strokes to actions:
private static final String TEXT_SUBMIT = "text-submit";
private static final String INSERT_BREAK = "insert-break";
...
private void initialize() {
InputMap input = inputTextArea.getInputMap();
KeyStroke enter = KeyStroke.getKeyStroke("ENTER");
KeyStroke shiftEnter = KeyStroke.getKeyStroke("shift ENTER");
input.put(shiftEnter, INSERT_BREAK); // input.get(enter)) = "insert-break"
input.put(enter, TEXT_SUBMIT);
ActionMap actions = inputTextArea.getActionMap();
actions.put(TEXT_SUBMIT, new AbstractAction() {
#Override
public void actionPerformed(ActionEvent e) {
submitText();
}
});
}
...
private void submitText() {
// TODO
}
The original action for ENTER - "insert-break" - is used for shift ENTER.
Try using keyTyped and not keyPressed. I beleive keyPressed gives you an event for the shift and for the enter, whereas keyTyped gives you one combined event with a modifier.
Instead of doing the actions immediately on receiving the event, sequence them for later by posting them using SwingUtilities.invokeLater(). The code should look like:
if(k.isShiftDown()) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
inputTextArea.append(" \n");
}
});
} else {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
//rest of the else body here
}
});
}
In my opinion, the problems seen here are because application-defined actions and internal actions are not being properly sequenced, leading to repaints happening before the text has been modified.
Related
So I have a button that when pressed needs to write the current mouse position out to a text box until the user presses shift, then it stops and leaves the most recent mouse position as the final text in the text box. Heres what I have done:
First a created the following class.
public class KeyListener extends KeyAdapter {
private boolean wasPressed = false;
private int keyCode;
public KeyListener(int keyCode) {
this.keyCode = keyCode;
}
#Override
public void keyReleased(KeyEvent e) {
System.out.println("CALLED");
if(e.getKeyCode() == keyCode)
wasPressed = true;
}
public void setState(boolean state) {
wasPressed = state;
}
public boolean getState() {
return wasPressed;
}
}
Then in my "main" class I have the following code.
JButton track1 = new JButton("Track");
KeyListener kl = new KeyListener(KeyEvent.VK_SHIFT);
...
public DisplayFrame() {
this.addKeyListener(kl);
track1.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event) {
kl.setState(false);
while(!kl.getState()) {
Point p = MouseInfo.getPointerInfo().getLocation();
topLeft.setText(p.getX() + "," + p.getY());
}
}
});
}
I then of course added the text box to a JPanel and it's displaying everything correctly, however, when I click the Track button nothing happens. I can tell that it is entering the loop, but no text is displayed in the textbox and pressing shift doesn't break the loop.
Try to make a new thread within the actionPerformed method like this:
Thread exampleThread = new Thread() {
public void run() {
//Do your actions within the new thread
}
};
//After the thread is made, we start it.
exampleThread.start();
You have to do this because the actionListener runs in a different thread.
I have a lot of different JFormattedTextFields with action and keylisteners. Every Field has a keylistener, so when I press enter I will focus the next JFormattedTextField. The Problem is, for some JFormattedTextFields my code is formatting the input and then sets the text new and for those selectAll() does not work.
JFormattedTextField a = new JFormattedTextField(someDouble);
JFormattedTextField b = new JFormattedTextField(someDouble2);
a.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
leasingfaktor1Field.selectAll();
if(...) {
//do something
a.setText(tausenderPunkt(someValue));
}
}
});
a.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == 10) {
b.requestFocusInWindow();
}
}
});
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
leasingfaktor1Field.selectAll();
if(...) {
//do something
b.setText(tausenderPunkt(someValue));
}
}
});
b.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == 10) {
c.requestFocusInWindow();
}
}
});
The function tausenderPunkt():
public String tausenderPunkt(double value) {
String s = String.format("%1$,.2f", value);
return s;
}
So when my cursor is in field a and i press enter the cursor goes to field b but does not select the text or values. When i do not use setText() i do not have the problem. Somebody has a solution?
Edit: For some JFormattedTextFields the solution was to add selectAll() to the keyAdapter, but not for all.
For example:
b.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == 10) {
c.requestFocusInWindow();
c.selectAll();
}
}
});
Edit2:
The problem seems to be when i create the JFormattedTextFields.
When i do not create them with a value in the constructor it works.
But i have to do.
Before moving to your next text field you should consider handling all the required conditions for the text field you are currently focused on and this would of course include the formatting of values or text supplied to that field. Once all the desired conditions are met then move on to the next text field.
In reality this can all be accomplished through the keyPressed event for your particular situation. There is no need for the actionPerformed event on any of your text fields, for example:
a.addKeyListener(new KeyAdapter() {
#Override
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_ENTER) {
checkConditions(a, b);
}
}
});
b.addKeyListener(new KeyAdapter() {
#Override
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_ENTER) {
checkConditions(b, c);
}
}
});
//---------- and so on -------------
Here is a simple method so as to eliminate the need for repetitious code:
private void checkConditions(JFormattedTextField fieldA, JFormattedTextField fieldB) {
// Make sure something is contained within fieldA and
// that it's actually numerical text.
if(!fieldA.getText().isEmpty() &&
fieldA.getText().matches("([-]?)\\d+([,]\\d+)?(([.]\\d+)?)")) {
// Convert the supplied text to Double and
// ensure the desired numerical formating.
String res = (String)tausenderPunkt(Double.parseDouble(fieldA.getText().replace(",","")));
fieldA.setText(res);
// Set Focus to our next text fieldB.
fieldB.requestFocusInWindow();
// Highlight the contents (if any) within the
// next text fieldB.
fieldB.selectAll();
}
// If fieldA is empty or fieldA does not contain
// numerical text then inform User and re-highlight
// the entry in fieldA.
else {
JOptionPane.showMessageDialog (null, "Please Enter Numerical Values Only!",
"Incorrect Entry", JOptionPane.WARNING_MESSAGE);
fieldA.selectAll();
}
}
If you want the contents of your first text field to be highlighted as soon as focus has been established upon it (tabbed to or clicked on) then consider using a FocusGained event for that component or any other component where you desire the same effect.
I Hope this has helped in some way.
EDITED!
So as to handle OP's particular situation.
String str=this.getText();
this.setText(str);
this.selectAll();
You can get the focus owner and remove the focusable feature:
Component focusOwner = FocusManager.getCurrentManager().getFocusOwner();
When you get the component, put this sentence after load it:
component.setFocusable(false);
I'm currently working on a little game. I'm using getKeyCode to move my character but the thing is that I don't want you to be able to keep moving if you hold in the button. Is there anyway I can use getKeyCode to only register on the first click and then won't register until I release the button and press again?
else if (event.getKeyCode()== KeyEvent.VK_UP)
{
spelare1.setLocation(spelare1.getX(),spelare1.getY()-50);
}
This is how it currently looks like.
I think you are confusing KeyEvents. VK_UP is the up arrow key. Use KeyEvent.KEY_RELEASED to react on a released key.
You can keep a boolean indicating whether the key is currently pressed. Then you can react once after each press, like in this example:
public static void main(String[] args) {
JFrame f = new JFrame();
f.addKeyListener(new KeyAdapter() {
private boolean pressed;
#Override
public void keyReleased(KeyEvent e) {
pressed = false;
}
#Override
public void keyPressed(KeyEvent e) {
if (!pressed) {
System.out.println("Key pressed: " + e.getKeyCode());
pressed = true;
}
}
});
SwingUtilities.invokeLater(new Runnable() {
public void run() {
f.setVisible(true);
}
});
}
Depending on your needs, you might want to have a separate state for each key, or just one shared state.
I've tried searching how to handle multiple key presses in java but all the solutions I've found are assuming that all keys are pressed.
I'm creating a very simple game where an image that I loaded will be moving along a canvas. i want it to move left, right, and jump by using the left, right, and up arrow keys. My problem is that, when I press the left and right keys, they work perfectly fine. But, when I press the up arrow key, it just jumps and stops moving all together.
I have an array list of all keys pressed and a run() method that checks all the keys pressed and does the specific job. But java only remembers the latest key that I pressed and it doesn't call the run() method once I press the up arrow key.
What do you suggest I do? I've tried threads but they mix up my code (or maybe I did something wrong?).
Here's my code:
public class Moving implements KeyListener {
ProgramClass bg; //this is another class
Set<Integer> pressed = new HashSet<Integer>();
public Moving (ProgramClass aa) {
bg = aa;
}
public void keyPressed (KeyEvent ae) {
pressed.add(ae.getKeyCode());
run();
}
public void keyTyped (KeyEvent ae) {
}
public void keyReleased (KeyEvent ae) {
pressed.remove (ae.getKeyCode());
if (bg.left==false) {
if (ae.getKeyCode()==KeyEvent.VK_UP) {
bg.yy -=40;
}
}
run();
}
public void run () {
if (bg.left==true) {
if (pressed.contains(KeyEvent.VK_A)) {}
if (pressed.contains(KeyEvent.VK_D)) {
if (bg.pic==true)
bg.pic = false;
else
bg.pic = true;
if (bg.x==-550)
bg.x = -2;
else
bg.x -= 2;
}
}
if (bg.left==false) {
if (pressed.contains(KeyEvent.VK_LEFT)) {
if (bg.pic==true)
bg.pic = false;
else
bg.pic = true;
if (bg.x==550)
bg.x = 2;
else
bg.x += 2;
}
if (pressed.contains(KeyEvent.VK_RIGHT)) {}
if (pressed.contains(KeyEvent.VK_UP)) {
bg.yy -=40;
}
}
}
}
Thanks!
I have 2 textfields in a JFrame and I want to validate the data in textfield1 when the focus gets lost from textfield1. So I have used FocusListener and used showMessageDialog() in the FocusLost() method and that then sets back the focus back to textfield1. It works fine when I click on any component inside the JFrame window other than textfield1,but when I click anywhere outside the JFrame window, the showMessageDialog() gets called two times and the focus goes to textfield2 whereas the focus should remain on textfield1.
#Override
public void focusGained(FocusEvent e) {}
#Override
public void focusLost(FocusEvent e) {
boolean show = false;
String theRegex = "[0-9]";
Pattern checkRegex = Pattern.compile(theRegex);
Matcher regexMatcher = checkRegex.matcher( MemberID );
while ( !regexMatcher.find() && show==false){
JOptionPane.showMessageDialog(null,"Please enter numbers","Validation Error",JOptionPane.ERROR_MESSAGE);
MemberID_Text.requestFocusInWindow();
MemberID_Text.selectAll();
show = true;
}
}
you can do this to verify if a number is entered, and avoid regex all together
class IntVerifier extends InputVerifier {
#Override public boolean verify(JComponent input) {
String text =((JTextField) input).getText();
int n = 0;
try {
n = Integer.parseInt(text); }
catch (NumberFormatException e) {
return false;
}
return true;
}
}
then use the input verifier on the text field
IntVerifier intv = new IntVerifier();
myTextField = new JTextField();
myTextField.setInputVerifier(intv);