T - the type of valuepublic interface HasValue<T> extends TakesValue<T>, HasValueChangeHandlers<T>
TakesValue to allow the value to be pulled back out, and to
throw ValueChangeEvent events.
An object that implements this interface should be a user input widget, where the user and programmer can both set and get the object's value. It is intended to provide a unified interface to widgets with "atomic" values, like Strings and Dates.
| Modifier and Type | Method and Description |
|---|---|
T |
getValue()
Gets this object's value.
|
void |
setValue(T value)
Sets this object's value without firing any events.
|
void |
setValue(T value,
boolean fireEvents)
Sets this object's value.
|
addValueChangeHandlerfireEventT getValue()
getValue in interface TakesValue<T>TakesValue.setValue(V)void setValue(T value)
It is acceptable to fail assertions or throw (documented) unchecked exceptions in response to bad values.
Widgets must accept null as a valid value. By convention, setting a widget to
null clears value, calling getValue() on a cleared widget returns null. Widgets
that can not be cleared (e.g. CheckBox) must find another valid meaning
for null input.
setValue in interface TakesValue<T>value - the object's new valueTakesValue.getValue()void setValue(T value, boolean fireEvents)
ValueChangeEvent when
fireEvents is true and the new value does not equal the existing value.
It is acceptable to fail assertions or throw (documented) unchecked exceptions in response to bad values.
value - the object's new valuefireEvents - fire events if true and value is new