|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectcom.jgoodies.binding.beans.Model
com.jgoodies.binding.value.AbstractValueModel
com.jgoodies.binding.value.AbstractVetoableValueModel
public abstract class AbstractVetoableValueModel
A ValueModel that allows to accept or reject proposed value changes. Useful to request information from the user or to perform operations before a value is changed.
Wraps a given subject ValueModel and always returns the subject value
as this model's value. Observes subject value changes and forwards
them to listeners of this model. If a value is set to this model,
the abstract method #proposedChange
is invoked. In this method
implementors define how to accept or reject value changes.
Implementors may veto against a proposed change based on the application state or by asking the user, and may also perform additional operations during the check, for example to save editor contents. Here's an example:
public class CheckPendingEditValueModel extends AbstractVetoableValueModel { public CheckPendingEditValueModel(ValueModel subject) { super(subject); } public boolean proposedChange(Object oldValue, Object proposedNewValue) { if (equals(oldValue, proposedNewValue)) return true; int option = JOptionPane.showConfirmDialog( Application.getDefaultParentFrame(), "Do you want to save the editor contents."); if (option == JOptionPane.YES_OPTION) model.save(); return option != JOptionPane.CANCEL_OPTION; } }
Field Summary |
---|
Fields inherited from class com.jgoodies.binding.value.AbstractValueModel |
---|
PROPERTYNAME_VALUE |
Constructor Summary | |
---|---|
protected |
AbstractVetoableValueModel(ValueModel subject)
Constructs an AbstractVetoableValueModel for the given ValueModel. |
Method Summary | |
---|---|
Object |
getValue()
Returns this model's current subject value. |
abstract boolean |
proposedChange(Object oldValue,
Object proposedNewValue)
Checks and answers whether the proposed value change shall be accepted or rejected. |
void |
setValue(Object newValue)
Sets the given value as new subject value if and only if 1) the new value differs from the old value and 2) the proposed change is accepted as checked by proposedChange(oldValue, newValue) . |
Methods inherited from class com.jgoodies.binding.value.AbstractValueModel |
---|
addValueChangeListener, booleanValue, doubleValue, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, fireValueChange, floatValue, getString, intValue, longValue, removeValueChangeListener, setValue, setValue, setValue, setValue, setValue, toString |
Methods inherited from class java.lang.Object |
---|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait |
Constructor Detail |
---|
protected AbstractVetoableValueModel(ValueModel subject)
subject
- the underlying (or wrapped) ValueModel
NullPointerException
- if the subject is null
Method Detail |
---|
public abstract boolean proposedChange(Object oldValue, Object proposedNewValue)
oldValue
- the value before the changeproposedNewValue
- the new value if the change is accepted
public final Object getValue()
public final void setValue(Object newValue)
proposedChange(oldValue, newValue)
.
newValue
- the value to set
|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |