javafx.scene.control.RadioButton Maven / Gradle / Ivy
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* 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
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*/
package javafx.scene.control;
import javafx.geometry.Pos;
import javafx.scene.control.skin.RadioButtonSkin;
import javafx.beans.value.WritableValue;
import javafx.css.StyleableProperty;
import javafx.scene.AccessibleAttribute;
import javafx.scene.AccessibleRole;
/**
* RadioButtons create a series of items where only one item can be
* selected. RadioButtons are a specialized {@link ToggleButton}.
* When a RadioButton is pressed and released a {@link javafx.event.ActionEvent}
* is sent. Your application can perform some action based
* on this event by implementing an {@link javafx.event.EventHandler} to
* process the {@link javafx.event.ActionEvent}.
*
*
* Only one RadioButton can be selected when placed in a {@link ToggleGroup}.
* Clicking on a selected RadioButton will have no effect. A RadioButton that is not
* in a ToggleGroup can be selected and unselected. By default a RadioButton is
* not in a ToggleGroup. Calling {@code ToggleGroup.getSelectedToggle()}
* will return you the RadioButton that has been selected.
*
*
* ToggleGroup group = new ToggleGroup();
* RadioButton button1 = new RadioButton("select first");
* button1.setToggleGroup(group);
* button1.setSelected(true);
* RadioButton button2 = new RadioButton("select second");
* button2.setToggleGroup(group);
*
* 
*
* @since JavaFX 2.0
*/
public class RadioButton extends ToggleButton {
/* *************************************************************************
* *
* Constructors *
* *
**************************************************************************/
/**
* Creates a radio button with an empty string for its label.
*/
public RadioButton() {
initialize();
}
/**
* Creates a radio button with the specified text as its label.
*
* @param text A text string for its label.
*/
public RadioButton(String text) {
setText(text);
initialize();
}
private void initialize() {
getStyleClass().setAll(DEFAULT_STYLE_CLASS);
setAccessibleRole(AccessibleRole.RADIO_BUTTON);
// alignment is styleable through css. Calling setAlignment
// makes it look to css like the user set the value and css will not
// override. Initializing alignment by calling set on the
// CssMetaData ensures that css will be able to override the value.
((StyleableProperty)(WritableValue)alignmentProperty()).applyStyle(null, Pos.CENTER_LEFT);
}
/* *************************************************************************
* *
* Methods *
* *
**************************************************************************/
/**
* Toggles the state of the radio button if and only if the RadioButton
* has not already selected or is not part of a {@link ToggleGroup}.
*/
@Override public void fire() {
// we don't toggle from selected to not selected if part of a group
if (getToggleGroup() == null || !isSelected()) {
super.fire();
}
}
/** {@inheritDoc} */
@Override protected Skin createDefaultSkin() {
return new RadioButtonSkin(this);
}
/* *************************************************************************
* *
* Stylesheet Handling *
* *
**************************************************************************/
private static final String DEFAULT_STYLE_CLASS = "radio-button";
/**
* Returns the initial alignment state of this control, for use
* by the JavaFX CSS engine to correctly set its initial value. This method
* is overridden to use Pos.CENTER_LEFT initially.
*
* @since 9
*/
@Override protected Pos getInitialAlignment() {
return Pos.CENTER_LEFT;
}
/* *************************************************************************
* *
* Accessibility handling *
* *
**************************************************************************/
/** {@inheritDoc} */
@Override
public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) {
switch (attribute) {
case SELECTED: return isSelected();
default: return super.queryAccessibleAttribute(attribute, parameters);
}
}
}