Java tutorial
/* * Copyright (c) 2010, 2017, 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.scene.control; import javafx.css.PseudoClass; import javafx.beans.property.ObjectProperty; import javafx.beans.property.ObjectPropertyBase; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.scene.AccessibleAction; import javafx.scene.Node; import javafx.beans.property.ReadOnlyBooleanProperty; import javafx.beans.property.ReadOnlyBooleanWrapper; /** * Base class for button-like UI Controls, including Hyperlinks, Buttons, * ToggleButtons, CheckBoxes, and RadioButtons. The primary contribution of * ButtonBase is providing a consistent API for handling the concept of button * "arming". In UIs, a button will typically only "fire" if some user gesture * occurs while the button is "armed". For example, a Button may be armed if * the mouse is pressed and the Button is enabled and the mouse is over the * button. In such a situation, if the mouse is then released, then the Button * is "fired", meaning its action takes place. * @since JavaFX 2.0 */ public abstract class ButtonBase extends Labeled { /*************************************************************************** * * * Constructors * * * **************************************************************************/ /** * Create a default ButtonBase with empty text. */ public ButtonBase() { } /** * Create a ButtonBase with the given text. * @param text null text is treated as the empty string */ public ButtonBase(String text) { super(text); } /** * Create a ButtonBase with the given text and graphic. * @param text null text is treated as the empty string * @param graphic a null graphic is acceptable */ public ButtonBase(String text, Node graphic) { super(text, graphic); } /*************************************************************************** * * * Properties * * * **************************************************************************/ /** * Indicates that the button has been "armed" such that a mouse release * will cause the button's action to be invoked. This is subtly different * from pressed. Pressed indicates that the mouse has been * pressed on a Node and has not yet been released. {@code arm} however * also takes into account whether the mouse is actually over the * button and pressed. * @return the property to indicate that the button has been "armed" */ public final ReadOnlyBooleanProperty armedProperty() { return armed.getReadOnlyProperty(); } private void setArmed(boolean value) { armed.set(value); } public final boolean isArmed() { return armedProperty().get(); } private ReadOnlyBooleanWrapper armed = new ReadOnlyBooleanWrapper() { @Override protected void invalidated() { pseudoClassStateChanged(ARMED_PSEUDOCLASS_STATE, get()); } @Override public Object getBean() { return ButtonBase.this; } @Override public String getName() { return "armed"; } }; /** * The button's action, which is invoked whenever the button is fired. This * may be due to the user clicking on the button with the mouse, or by * a touch event, or by a key press, or if the developer programmatically * invokes the {@link #fire()} method. * @return the property to represent the button's action, which is invoked * whenever the button is fired */ public final ObjectProperty<EventHandler<ActionEvent>> onActionProperty() { return onAction; } public final void setOnAction(EventHandler<ActionEvent> value) { onActionProperty().set(value); } public final EventHandler<ActionEvent> getOnAction() { return onActionProperty().get(); } private ObjectProperty<EventHandler<ActionEvent>> onAction = new ObjectPropertyBase<EventHandler<ActionEvent>>() { @Override protected void invalidated() { setEventHandler(ActionEvent.ACTION, get()); } @Override public Object getBean() { return ButtonBase.this; } @Override public String getName() { return "onAction"; } }; /*************************************************************************** * * * Methods * * * **************************************************************************/ /** * Arms the button. An armed button will fire an action (whether that be * the action of a {@link Button} or toggling selection on a * {@link CheckBox} or some other behavior) on the next expected UI * gesture. * * Note: This function is intended to be used by experts, primarily * by those implementing new Skins or Behaviors. It is not common * for developers or designers to access this function directly. */ public void arm() { setArmed(true); } /** * Disarms the button. See {@link #arm()}. * * Note: This function is intended to be used by experts, primarily * by those implementing new Skins or Behaviors. It is not common * for developers or designers to access this function directly. */ public void disarm() { setArmed(false); } /** * Invoked when a user gesture indicates that an event for this * {@code ButtonBase} should occur. * <p> * If invoked, this method will be executed regardless of the status of * {@link #arm}. * </p> */ public abstract void fire(); /*************************************************************************** * * * Stylesheet Handling * * * **************************************************************************/ private static final PseudoClass ARMED_PSEUDOCLASS_STATE = PseudoClass.getPseudoClass("armed"); /*************************************************************************** * * * Accessibility handling * * * **************************************************************************/ /** {@inheritDoc} */ @Override public void executeAccessibleAction(AccessibleAction action, Object... parameters) { switch (action) { case FIRE: fire(); break; default: super.executeAccessibleAction(action); } } }