I've got one textField where I only accept numbers from the keyboard, but now I have to change it as it's a "price textField" and I would also need to accept a dot "." for any kind of prices.
How can I change this in order to get what I need?
ptoMinimoField = new JTextField();
ptoMinimoField.setBounds(348, 177, 167, 20);
contentPanel.add(ptoMinimoField);
ptoMinimoField.setColumns(10);
ptoMinimoField.addKeyListener(new KeyAdapter() {
public void keyTyped(KeyEvent e) {
char caracter = e.getKeyChar();
if (((caracter < '0') || (caracter > '9'))
&& (caracter != '\b')) {
e.consume();
}
}
});
As suggested by Oracle ,Use Formatted Text Fields
Formatted text fields provide a way for developers to specify the valid set of characters that can be typed in a text field.
amountFormat = NumberFormat.getNumberInstance();
...
amountField = new JFormattedTextField(amountFormat);
amountField.setValue(new Double(amount));
amountField.setColumns(10);
amountField.addPropertyChangeListener("value", this);
I just use a try-catch block:
try {// if is number
Integer.parseInt(String);
} catch (NumberFormatException e) {
// else then do blah
}
JTextField txField = new DoubleJTextField();
Create a file DoubleJTextField.java and be happy
public class DoubleJTextField extends JTextField {
public DoubleJTextField(){
addKeyListener(new KeyAdapter() {
public void keyTyped(KeyEvent e) {
char ch = e.getKeyChar();
if (!isNumber(ch) && !isValidSignal(ch) && !validatePoint(ch) && ch != '\b') {
e.consume();
}
}
});
}
private boolean isNumber(char ch){
return ch >= '0' && ch <= '9';
}
private boolean isValidSignal(char ch){
if( (getText() == null || "".equals(getText().trim()) ) && ch == '-'){
return true;
}
return false;
}
private boolean validatePoint(char ch){
if(ch != '.'){
return false;
}
if(getText() == null || "".equals(getText().trim())){
setText("0.");
return false;
}else if("-".equals(getText())){
setText("-0.");
}
return true;
}
}
Don't ever use a KeyListener for this. Your code above has two serious bugs, both caused by the use of a KeyListener. First, it will miss any text that gets pasted in. Whenever I find a field that filters out non-digits, I always try to paste in some text, just for fun. Nine times out of ten, the text gets accepted, because they used a key listener.
Second, you didn't filter out modifiers. If the user tries to save their work by typing control-s while they're in this field, your key listener will consume the event. And if your application assigns, say, a control-5 or alt-5 shortcut to some action, this KeyListener will add a 5 to the field when they type it, even though the user wasn't trying to type a character. You did figure out that you needed to pass the backspace key, but that's not all you need to pass. Your arrow keys won't work. Neither will your function keys. You can fix all these problems, but it starts to be a lot of work.
There's a third disadvantage, but it only shows up if you adapt your application to a foreign alphabet, particularly one that takes multiple keystrokes to generate a single character, like Chinese. These alphabets make KeyListeners useless.
The trouble is this. You need to filter characters, but KeyListeners aren't about characters, they're about keystrokes, which are not the same thing: Not all keystrokes generate characters, and not all characters are generated by keystrokes. You need an approach that looks at characters after they've been generated, and after modified keystrokes have already been filtered out.
The simplest approach is to use a JFormattedTextField, but I've never liked that approach, because it doesn't format or filter as you type. So instead, I will use a DocumentFilter. DocumentFilters don't operate on keystrokes, they operate on the text strings as they get inserted to your JTextField's data model. Hence, all the control-keys, arrow and function keys and such don't even reach the DocumentFilter. All pasted text goes through the DocumentFilter, too. And, for languages that take three keystrokes to generate a single character, the DocumentFilter doesn't get invoked until the character is generated. Here's what it looks like:
ptoMinimoField = new JTextField();
ptoMinimoField.setBounds(348, 177, 167, 20); // Don't do this! See below.
contentPanel.add(ptoMinimoField);
ptoMinimoField.setColumns(10);
PlainDocument document = (PlainDocument) ptoMinimoField.getDocument();
document.setDocumentFilter(new DigitFilter());
}
The DigitFilter class looks like this:
public class DigitFilter extends DocumentFilter {
#Override
public void insertString(FilterBypass fb, int offset, String text,
AttributeSet attr) throws BadLocationException {
super.insertString(fb, offset, revise(text), attr);
}
#Override
public void replace(FilterBypass fb, int offset, int length, String text,
AttributeSet attrs) throws BadLocationException {
super.replace(fb, offset, length, revise(text), attrs);
}
private String revise(String text) {
StringBuilder builder = new StringBuilder(text);
int index = 0;
while (index < builder.length()) {
if (accept(builder.charAt(index))) {
index++;
} else {
// Don't increment index here, or you'll skip the next character!
builder.deleteCharAt(index);
}
}
return builder.toString();
}
/**
* Determine if the character should remain in the String. You may
* override this to get any matching criteria you want.
* #param c The character in question
* #return true if it's valid, false if it should be removed.
*/
public boolean accept(final char c) {
return Character.isDigit(c) || c == '.';
}
}
You could write this as an inner class, but I created a separate class so you can override the accept() method to use any criteria you want. You may also notice that I don't test for digits by writing this:
(c < '0') || (c > '9')
Instead, I do this:
Character.isDigit()
This is faster, cleaner, and works with foreign numbering systems. I also don't need your test for the backspace character, '\b'. I'm guessing that your first KeyListener was filtering out the backspace key, which was your first clue that it was the wrong approach.
And on an unrelated note, don't hard code your component positions. Learn how to use the LayoutManagers. They're easy to use, and they'll make your code much easier to maintain.
Have you looked at a JFormattedTextField? It would seem it does what you want.
Enter the double number of JTextField in java
private boolean dot = false;
private void txtMarkKeyTyped(java.awt.event.KeyEvent evt) {
char vChar = evt.getKeyChar();
if (txtMark.getText().equals(""))
dot = false;
if (dot == false){
if (vChar == '.') dot = true;
else if (!(Character.isDigit(vChar)
|| (vChar == KeyEvent.VK_BACK_SPACE)
|| (vChar == KeyEvent.VK_DELETE))) {
evt.consume();
}
} else {
if (!(Character.isDigit(vChar)
|| (vChar == KeyEvent.VK_BACK_SPACE)
|| (vChar == KeyEvent.VK_DELETE))) {
evt.consume();
}
}
}
This bit of code;
if (((caracter < '0') || (caracter > '9'))
&& (caracter != '\b')) {
decides whether to consume the key event. You need to update the condition so it doesn't consume the dot character.
Just right click on TextField / events / key / keytyped
if(!Character.isDigit(evt.getKeyChar())){
evt.consume();}
/////////////
JTextField ptoMinimoField = new JTextField();
ptoMinimoField.addKeyListener(new KeyAdapter() {
public void keyTyped(KeyEvent e) {
boolean ret = true;
try {
Double.parseDouble(ptoMinimoField.getText()+e.getKeyChar());
}catch (NumberFormatException ee) {
ret = false;
}
if (!ret) {
e.consume();
}
}
});
maybe can help you for filtering keytyped just number and dot
public void filterHanyaAngkaDot(java.awt.event.KeyEvent evt){
char c = evt.getKeyChar();
if (! ((Character.isDigit(c) ||
(c == KeyEvent.VK_BACK_SPACE) ||
(c == KeyEvent.VK_DELETE))
)&& c==KeyEvent.VK_COMMA
)
{
evt.consume();
}
}
JTextField txtMyTextField = new JTextField();
numOnly(txtMyTextField);
public void numOnly(Object objSource){
((Component) objSource).addKeyListener(new KeyListener() {
#Override
public void keyTyped(KeyEvent e) {
String filterStr = "0123456789.";
char c = (char)e.getKeyChar();
if(filterStr.indexOf(c)<0){
e.consume();
}
}
#Override
public void keyReleased(KeyEvent e) {}
#Override
public void keyPressed(KeyEvent e) {}
});
}
WARNING: This function does not follow proper java documentation
guide.
I have been using this solution, it's simple and efficient:
jtextfield.addKeyListener(new KeyAdapter() {
public void keyTyped(KeyEvent e) {
char vChar = e.getKeyChar();
if (!(Character.isDigit(vChar)
|| (vChar == KeyEvent.VK_BACK_SPACE)
|| (vChar == KeyEvent.VK_DELETE))) {
e.consume();
}
}
});
private boolean point = false;
private void txtProductCostPriceAddKeyTyped(java.awt.event.KeyEvent evt)
{
char Char = evt.getKeyChar();
if (txtProductCostPriceAdd.getText().equals(""))
point = false;
if (point == false){
if (Char == '.') point = true;
else if (!(Character.isDigit(Char) || (Char == KeyEvent.VK_BACK_SPACE) || (Char == KeyEvent.VK_DELETE))) {
evt.consume();
}
} else {
if (!(Character.isDigit(Char) || (Char == KeyEvent.VK_BACK_SPACE) || (Char == KeyEvent.VK_DELETE))) {
evt.consume();
}
}
}
JTextField textField = new JTextField();
textField.setColumns(10);
textField.addKeyListener(new KeyAdapter() {
#Override
public void KeyTyped(KeyEvent e) {
if (!(e.getKeyChar() >= '0' && e.getKeyChar() <= '9')) {
e.consume();
}
}
})
this is the easiest method i have found so far, and it works without any error
Related
So I have a textfield which I want to be max length 10 and only letters, this is what I've came up with:
private void textField1KeyTyped(java.awt.event.KeyEvent evt) {
char c= evt.getKeyChar();
if( !(Character.isAlphabetic(c)) ){
evt.consume();
}
if ((textField1.getText().length()) > 10){
evt.consume();
}
}
It kind of works but I've seen some tutorials that use something like this:
private void textField1KeyTyped(java.awt.event.KeyEvent evt) {
char c= evt.getKeyChar();
if( (Character.isAlphabetic(c)) ){
if((textField1.getText().length()) <= 10){
textField1.setEditable(true);
}else {
textField1.setEditable(false);
}
}else {
if( (c == KeyEvent.VK_BACK_SPACE) || (c == KeyEvent.VK_DELETE) ){
textField1.setEditable(true);
}else {
textField1.setEditable(false);
}
}
}
Which one is right?
Both will stop the text-field from consuming further keys.
calling InputEvent.consume() marks the event as consumed, so that the textfield will not consume it and add the key to it's contents.
See What does e.consume() do in java
disabling editing on the textfield with setEditable(false) will also prevent the textfield from editing, that is consuming the key. But it also makes this behaviour, the lock, visible to the user.
So I have a JTextField which receives a 10-digit number input and edits the given phone number in this format XXX-XXX-XXXX.
When one tries to erase past the last four numbers, it is imposible to delete the hyphen.
I tried to fix this using the KeyTyped method but I found out that BackSpace key can not use this method, only KeyPressed or KeyRelease, so I used the KeyReleased method for it and now it will erase the hyphens, but it will erase more than 1 digit per everytime I hit the backspace key.
If anyone could succesfully accomplish this in a better way that allows to erase only one digit per strike I'm all eyes.
This is the listener for my JTextField:
public class PhoneList implements KeyListener {
#Override
public void keyTyped(KeyEvent e) {
// Allow Numbers only
char testChar = e.getKeyChar();
if (!Character.isDigit(testChar)) {
e.consume();
}
String pnText = pntf.getText();
int pnLength = pnText.length();
// Add the hyphens
if (pnLength == 3 || pnLength == 7) {
pntf.setText(pnText + "-");
}
// Limited to 10-digit numbers
if (pnLength >= 12) {
e.consume();
}
}
#Override
public void keyPressed(KeyEvent e) { //Empty }
#Override
public void keyReleased(KeyEvent e) {
// Erase numbers and also hyphens
boolean released = false;
if (e.getKeyCode() == KeyEvent.VK_BACK_SPACE && released == false) {
String pnTxt = pntf.getText();
int pnL = pnTxt.length();
if (pnL > 1) {
int start = 0;
int end = pnL - 1;
String pnErased = pnTxt.substring(start, end);
released = true;
pntf.setText(pnErased);
} else {
pntf.setText("");
released = true;
}
}
}
}
I'm writing a CashRegister program and I'm currently working on the CashierView where I have added an option for the Cashier to input the amount of cash received by the customer. I now formatted it so that the user only can input numbers and 1 period. I now want to limit the numbers you can input after the period to two. I'm struggling to make this work.
I commented out one of the codes that I tried, but didn't work, incase it might be interesting.
Appreciate all the help!
Br,
Victor
private void jCashReceivedKeyTyped(java.awt.event.KeyEvent evt) {
char c = evt.getKeyChar(); //Allows input of only Numbers and periods in the textfield
//boolean tail = false;
if ((Character.isDigit(c) || (c == KeyEvent.VK_BACKSPACE) || c == KeyEvent.VK_PERIOD)) {
int period = 0;
if (c == KeyEvent.VK_PERIOD) { //Allows only one period to be added to the textfield
//tail = false;
String s = getTextFieldCash();
int dot = s.indexOf(".");
period = dot;
if (dot != -1) {
evt.consume();
}
}
//. if (tail=true){ //This is the code that I tried to use to limit input after the period to two
// String x = getTextFieldCashTail();
// if (x.length()>1){
// evt.consume();
// }
// }
}
else {
evt.consume();
}
}
If you're dead set on doing this with a KeyEvent, here's one possible method:
private void jCashReceivedKeyTyped(java.awt.event.KeyEvent evt) {
char c = evt.getKeyChar(); //Allows input of only Numbers and periods in the textfield
if ((Character.isDigit(c) || (c == KeyEvent.VK_BACK_SPACE) || c == KeyEvent.VK_PERIOD)) {
String s = getTextFieldCash();
int dot = s.indexOf(".");
if(dot != -1 && c == KeyEvent.VK_PERIOD) {
evt.consume();
} else if(dot != -1 && c != KeyEvent.VK_BACK_SPACE){
String afterDecimal = s.substring(dot + 1);
if (afterDecimal.length() > 2) {
evt.consume();
}
}
}
}
Hope this helps. Just keep in mind that by listening to a KeyEvent, if someone copies and pastes values into your JTextField, this won't catch that. If you want to catch any possible type of input, you'll want to use a DocumentListener. If you're wondering how to use a DocumentListener, here is some code that shows how to use it on a JTextField.
I am trying to verify a text in SWT to allow only binary numbers and it works, but my problem is that I have a button that I need to reset the field but it doesn't work.
Here is the code
DACMUX.addVerifyListener(new VerifyListener() {
public void verifyText(VerifyEvent e) {
e.doit = false;
char myChar = e.character;
if (myChar == '1' || myChar == '0' || myChar == '\b'){
e.doit = true;
}
}
});
reset.addSelectionListener(new SelectionListener() {
#Override
public void widgetSelected(SelectionEvent e) {
DACMUX.setText("");
}
#Override
public void widgetDefaultSelected(SelectionEvent e) {
// TODO Auto-generated method stub
}
});
Interesting case you got there. Took me a while to figure it out.
Right, so here goes: The VerifyListener is fired after you call setText(""). It checks your condition and it validates to false, so nothing changes.
To make it work, you need to add one additional OR case to your if, which checks if Event#text equals "". This is the case when you call setText(""). It won't mess up you other logic.
So here is the working if:
if (myChar == '1' || myChar == '0' || myChar == '\b' || e.text.equals(""))
{
e.doit = true;
}
I think this may be very simple, but it swallow my time.
I am using TextItem In GWT in my JAVA Application to get the price input from the the user.
I am trying to stop allowing more than one dot (".") on text item. All my exercise are gone to fail.
I am using regular expression; Try to handle the key chars on BlurHandler event of TextItem both drag me a wrong.
Can anybody help me to achieve the above?
Thank you in advance.
Something like this is what I use:
amount = new TextBox();
amount.setVisibleLength(10);
amount.addKeyPressHandler(new KeyPressHandler() {
public void onKeyPress(KeyPressEvent event) {
if (!checkNumeric(amount.getText(), event.getCharCode()))
amount.cancelKey();
}
});
public boolean checkNumeric(String text, char keycode) {
if (!Character.isDigit(keycode) && keycode != '.' && keycode != '-'
&& keycode != KeyCodes.KEY_BACKSPACE
&& keycode != KeyCodes.KEY_TAB) {
return false;
}
if (keycode == '-') {
if (!text.isEmpty()) {
return false;
}
}
if (keycode == '.') {
if (text.contains(".")) {
return false;
}
}
return true;
}