Leading plus in number textfields

Support
#1

What would be the easiest way to make a number textfield accepting a leading plus?
It throws an “Alert input error” if the number starts with a plus (e.g. “+123” for 123).

I tried to remove the “+” by using a text change listener, but it takes a little while to fire while the number validation jumps in immediately when lost focus.

Background:
I use an electronic scale (with a keyboard emulation driver) to input values in some textfields and unfortunately the leading plus sign cannot be disabled.

Thanks!

#2

You can do it by overriding the default Datatype provided by the framework. For attributes of BigDecimal type it would be as follows.

  • Create a class extending BigDecimalDatatype and override its parse() method:

    package com.company.sales;

import com.haulmont.chile.core.datatypes.impl.BigDecimalDatatype;
import org.dom4j.Element;

import java.math.BigDecimal;
import java.text.ParseException;
import java.util.Locale;

public class MyBigDecimalDatatype extends BigDecimalDatatype {

    public MyBigDecimalDatatype(Element element) {
        super(element);
    }

    @Override
    public BigDecimal parse(String value, Locale locale) throws ParseException {
        if (value != null && value.startsWith("+")) {
            value = value.substring(1);
        }
        return super.parse(value, locale);
    }
}

  • Register the class in your metadata.xml with id="decimal":

    <metadata xmlns="http://schemas.haulmont.com/cuba/metadata.xsd">

    <datatypes>
        <datatype id="decimal" class="com.company.sales.MyBigDecimalDatatype"
                default="true"
                format="0.####" decimalSeparator="." groupingSeparator=""/>
    </datatypes>

    <metadata-model root-package="com.company.sales" namespace="sales"/>

</metadata>

  • That’s it. Leading “+” will be discarded in all fields bound to BigDecimal attributes right after the field lost focus.

1 Like
#3

I’m not exactly sure how all this works in background, but it works… thank you!