DisplaySpan

DisplaySpan<T> shows a value of any type as a span. It works out how to render the value itself, which is what makes it the display counterpart of a Text2.

DisplaySpan<BigDecimal> price = new DisplaySpan<>(BigDecimal.class);
price.setConverter(ConverterRegistry.getConverterInstance(MoneyBigDecimalFullConverter.class));
price.setValue(new BigDecimal("14.95"));

FormBuilder fb = new FormBuilder(cp);
fb.label("Price").control(price);

How it decides what to show

Constructors

What it renders

How it decides what to show

createContent() tries, in this order, and stops at the first that works:

the converter, when one is set - it must convert the value;
the renderer, when one is set - it may put anything at all inside the span, and is asked even for a null value;
the empty string when the value is null;
the default converter for the value's own class, from the ConverterRegistry;
the domain label when the value has domain values - an enum or a boolean gets its metadata label;
failing all that, the class's default renderer, which ends at toString().

That order is why a DisplaySpan<Date> shows a properly formatted date without being told anything, and why an enum shows its label rather than its constant name.

Method	What it does
`setValue(T)` / `getValue()`	the value; setting it rebuilds the span
`setConverter(IConverter<T>)`	convert the value to text yourself
`setRenderer(IRenderInto<T>)`	build the content yourself
`setEmptyString(String)`	what to show for a `null` value - nothing at all by default
`defineFrom(PropertyMetaModel)`	take the hint and, for a number, the numeric converter from a property

A converter and a renderer cannot both be set: setRenderer() on a span that already has a converter throws. Clear the converter first.

Constructors

Constructor	Use it for
`new DisplaySpan<>(Class<T>)`	the usual case: the type, no value yet
`new DisplaySpan<>(Class<T>, T)`	the type and its first value
`new DisplaySpan<>(PropertyMetaModel<T>)`	configured from a property, through `defineFrom()`
`new DisplaySpan<>(T literal)`	a value whose class speaks for itself

What it renders

A <span> with the text in it, and nothing else - no wrapper, no control class. That is what makes it right inside running text, inside a table cell, or next to another value. When it has to line up with the input controls in a form, use DisplayControl instead.