javafx.beans.property.DoubleProperty Maven / Gradle / Ivy
Show all versions of openjfx-78-backport Show documentation
/*
* Copyright (c) 2011, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package javafx.beans.property;
import com.sun.javafx.binding.BidirectionalBinding;
import com.sun.javafx.binding.ExpressionHelper;
import javafx.beans.binding.Bindings;
import javafx.beans.value.ObservableValue;
import javafx.beans.value.WritableDoubleValue;
import com.sun.javafx.binding.Logging;
import javafx.beans.InvalidationListener;
import javafx.beans.Observable;
import javafx.beans.WeakInvalidationListener;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableDoubleValue;
/**
* This class defines a {@link Property} wrapping a {@code double} value.
*
* The value of a {@code DoubleProperty} can be get and set with {@link #get()},
* {@link #getValue()}, {@link #set(double)}, and {@link #setValue(Number)}.
*
* A property can be bound and unbound unidirectional with
* {@link #bind(ObservableValue)} and {@link #unbind()}. Bidirectional bindings
* can be created and removed with {@link #bindBidirectional(Property)} and
* {@link #unbindBidirectional(Property)}.
*
* The context of a {@code DoubleProperty} can be read with {@link #getBean()}
* and {@link #getName()}.
*
* Note: setting or binding this property to a null value will set the property to "0.0". See {@link #setValue(java.lang.Number) }.
*
* @see javafx.beans.value.ObservableDoubleValue
* @see javafx.beans.value.WritableDoubleValue
* @see ReadOnlyDoubleProperty
* @see Property
*
* @since JavaFX 2.0
*/
public abstract class DoubleProperty extends ReadOnlyDoubleProperty implements
Property, WritableDoubleValue {
/**
* {@inheritDoc}
*/
@Override
public void setValue(Number v) {
if (v == null) {
Logging.getLogger().info("Attempt to set double property to null, using default value instead.", new NullPointerException());
set(0.0);
} else {
set(v.doubleValue());
}
}
/**
* {@inheritDoc}
*/
@Override
public void bindBidirectional(Property other) {
Bindings.bindBidirectional(this, other);
}
/**
* {@inheritDoc}
*/
@Override
public void unbindBidirectional(Property other) {
Bindings.unbindBidirectional(this, other);
}
/**
* Returns a string representation of this {@code DoubleProperty} object.
* @return a string representation of this {@code DoubleProperty} object.
*/
@Override
public String toString() {
final Object bean = getBean();
final String name = getName();
final StringBuilder result = new StringBuilder(
"DoubleProperty [");
if (bean != null) {
result.append("bean: ").append(bean).append(", ");
}
if ((name != null) && (!name.equals(""))) {
result.append("name: ").append(name).append(", ");
}
result.append("value: ").append(get()).append("]");
return result.toString();
}
/**
* Returns a {@code DoubleProperty} that wraps a
* {@link javafx.beans.property.Property} and is
* bidirectionally bound to it.
* Changing this property will result in a change of the original property.
*
*
* This is very useful when bidirectionally binding an ObjectProperty and
* a DoubleProperty.
*
*
* DoubleProperty doubleProperty = new SimpleDoubleProperty(1.0);
* ObjectProperty<Double> objectProperty = new SimpleObjectProperty<>(2.0);
*
* // Need to keep the reference as bidirectional binding uses weak references
* DoubleProperty objectAsDouble = DoubleProperty.doubleProperty(objectProperty);
*
* doubleProperty.bindBidirectional(objectAsDouble);
*
*
*
* Another approach is to convert the DoubleProperty to ObjectProperty using
* {@link #asObject()} method.
*
* Note: null values in the source property will be interpreted as 0.0
*
* @param property
* The source {@code Property}
* @return A {@code DoubleProperty} that wraps the
* {@code Property}
* @throws NullPointerException
* if {@code value} is {@code null}
* @see #asObject()
* @since JavaFX 8.0
*/
public static DoubleProperty doubleProperty(final Property property) {
if (property == null) {
throw new NullPointerException("Property cannot be null");
}
return new DoublePropertyBase() {
{
BidirectionalBinding.bindNumber(property, this);
}
@Override
public Object getBean() {
return null; // Virtual property, no bean
}
@Override
public String getName() {
return property.getName();
}
@Override
protected void finalize() throws Throwable {
try {
BidirectionalBinding.unbindNumber(property, this);
} finally {
super.finalize();
}
}
};
}
/**
* Creates an {@link javafx.beans.property.ObjectProperty}
* that bidirectionally bound to this {@code DoubleProperty}. If the
* value of this {@code DoubleProperty} changes, the value of the
* {@code ObjectProperty} will be updated automatically and vice-versa.
*
*
* Can be used for binding an ObjectProperty to DoubleProperty.
*
*
* DoubleProperty doubleProperty = new SimpleDoubleProperty(1.0);
* ObjectProperty<Double> objectProperty = new SimpleObjectProperty<>(2.0);
*
* objectProperty.bind(doubleProperty.asObject());
*
*
* @return the new {@code ObjectProperty}
* @since JavaFX 8.0
*/
@Override
public ObjectProperty asObject() {
return new ObjectPropertyBase () {
{
BidirectionalBinding.bindNumber(this, DoubleProperty.this);
}
@Override
public Object getBean() {
return null; // Virtual property, does not exist on a bean
}
@Override
public String getName() {
return DoubleProperty.this.getName();
}
@Override
protected void finalize() throws Throwable {
try {
BidirectionalBinding.unbindNumber(this, DoubleProperty.this);
} finally {
super.finalize();
}
}
};
}
}