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 com.sun.javafx.scene.ParentHelper; import com.sun.javafx.scene.traversal.ParentTraversalEngine; import javafx.beans.property.BooleanProperty; import javafx.beans.property.BooleanPropertyBase; import javafx.beans.property.ObjectProperty; import javafx.beans.property.ObjectPropertyBase; import javafx.beans.value.ChangeListener; import javafx.beans.value.WritableValue; import javafx.event.ActionEvent; import javafx.geometry.Pos; import javafx.scene.AccessibleAttribute; import javafx.scene.AccessibleRole; import javafx.scene.Node; import javafx.css.PseudoClass; import javafx.scene.control.skin.ToggleButtonSkin; import javafx.css.StyleableProperty; /** * A {@code ToggleButton} is a specialized control which has the ability to be * selected. Typically a {@code ToggleButton} is rendered similarly to a Button. * However, they are two different types of Controls. A Button is a "command" * button which invokes a function when clicked. A {@code ToggleButton} on the * other hand is simply a control with a Boolean indicating whether it has been * selected. * <p> * {@code ToggleButton} can also be placed in groups. By default, a * {@code ToggleButton} is not in a group. When in groups, only one * {@code ToggleButton} at a time within that group can be selected. To put two * {@code ToggleButtons} in the same group, simply assign them both the same * value for {@link ToggleGroup}. * </p> * <p> * Unlike {@link RadioButton RadioButtons}, {@code ToggleButtons} in a * {@code ToggleGroup} do not attempt to force at least one selected * {@code ToggleButton} in the group. That is, if a {@code ToggleButton} is * selected, clicking on it will cause it to become unselected. With * {@code RadioButton}, clicking on the selected button in the group will have * no effect. * </p> * * <p>Example:</p> * <pre><code> * ToggleButton tb1 = new ToggleButton("toggle button 1"); * ToggleButton tb2 = new ToggleButton("toggle button 2"); * ToggleButton tb3 = new ToggleButton("toggle button 3"); * ToggleGroup group = new ToggleGroup(); * tb1.setToggleGroup(group); * tb2.setToggleGroup(group); * tb3.setToggleGroup(group); * </code></pre> * * <p> * MnemonicParsing is enabled by default for ToggleButton. * </p> * @since JavaFX 2.0 */ // TODO Mention the semantics when binding "selected" on multiple toggle buttons // which are all on the same toggle group, and how the selected state on the // toggle group is affected or not in such a case. public class ToggleButton extends ButtonBase implements Toggle { /*************************************************************************** * * * Constructors * * * **************************************************************************/ /** * Creates a toggle button with an empty string for its label. */ public ToggleButton() { initialize(); } /** * Creates a toggle button with the specified text as its label. * * @param text A text string for its label. */ public ToggleButton(String text) { setText(text); initialize(); } /** * Creates a toggle button with the specified text and icon for its label. * * @param text A text string for its label. * @param graphic the icon for its label. */ public ToggleButton(String text, Node graphic) { setText(text); setGraphic(graphic); initialize(); } private void initialize() { getStyleClass().setAll(DEFAULT_STYLE_CLASS); setAccessibleRole(AccessibleRole.TOGGLE_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<Pos>) (WritableValue<Pos>) alignmentProperty()).applyStyle(null, Pos.CENTER); setMnemonicParsing(true); // enable mnemonic auto-parsing by default } /*************************************************************************** * * * Properties * * * **************************************************************************/ /** * Indicates whether this toggle button is selected. This can be manipulated * programmatically. */ private BooleanProperty selected; public final void setSelected(boolean value) { selectedProperty().set(value); } public final boolean isSelected() { return selected == null ? false : selected.get(); } public final BooleanProperty selectedProperty() { if (selected == null) { selected = new BooleanPropertyBase() { @Override protected void invalidated() { final boolean selected = get(); final ToggleGroup tg = getToggleGroup(); // Note: these changes need to be done before selectToggle/clearSelectedToggle since // those operations change properties and can execute user code, possibly modifying selected property again pseudoClassStateChanged(PSEUDO_CLASS_SELECTED, selected); notifyAccessibleAttributeChanged(AccessibleAttribute.SELECTED); if (tg != null) { if (selected) { tg.selectToggle(ToggleButton.this); } else if (tg.getSelectedToggle() == ToggleButton.this) { tg.clearSelectedToggle(); } } } @Override public Object getBean() { return ToggleButton.this; } @Override public String getName() { return "selected"; } }; } return selected; } /** * The {@link ToggleGroup} to which this {@code ToggleButton} belongs. A * {@code ToggleButton} can only be in one group at any one time. If the * group is changed, then the button is removed from the old group prior to * being added to the new group. */ private ObjectProperty<ToggleGroup> toggleGroup; public final void setToggleGroup(ToggleGroup value) { toggleGroupProperty().set(value); } public final ToggleGroup getToggleGroup() { return toggleGroup == null ? null : toggleGroup.get(); } public final ObjectProperty<ToggleGroup> toggleGroupProperty() { if (toggleGroup == null) { toggleGroup = new ObjectPropertyBase<ToggleGroup>() { private ToggleGroup old; private ChangeListener<Toggle> listener = (o, oV, nV) -> ParentHelper .getTraversalEngine(ToggleButton.this) .setOverriddenFocusTraversability(nV != null ? isSelected() : null); @Override protected void invalidated() { final ToggleGroup tg = get(); if (tg != null && !tg.getToggles().contains(ToggleButton.this)) { if (old != null) { old.getToggles().remove(ToggleButton.this); } tg.getToggles().add(ToggleButton.this); final ParentTraversalEngine parentTraversalEngine = new ParentTraversalEngine( ToggleButton.this); ParentHelper.setTraversalEngine(ToggleButton.this, parentTraversalEngine); // If there's no toggle selected, do not override parentTraversalEngine.setOverriddenFocusTraversability( tg.getSelectedToggle() != null ? isSelected() : null); tg.selectedToggleProperty().addListener(listener); } else if (tg == null) { old.selectedToggleProperty().removeListener(listener); old.getToggles().remove(ToggleButton.this); ParentHelper.setTraversalEngine(ToggleButton.this, null); } old = tg; } @Override public Object getBean() { return ToggleButton.this; } @Override public String getName() { return "toggleGroup"; } }; } return toggleGroup; } /*************************************************************************** * * * Methods * * * **************************************************************************/ /** {@inheritDoc} */ @Override public void fire() { // TODO (aruiz): if (!isReadOnly(isSelected()) { if (!isDisabled()) { setSelected(!isSelected()); fireEvent(new ActionEvent()); } } /** {@inheritDoc} */ @Override protected Skin<?> createDefaultSkin() { return new ToggleButtonSkin(this); } /*************************************************************************** * * * Stylesheet Handling * * * **************************************************************************/ private static final String DEFAULT_STYLE_CLASS = "toggle-button"; private static final PseudoClass PSEUDO_CLASS_SELECTED = PseudoClass.getPseudoClass("selected"); /** * 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 initially. * * @since 9 */ @Override protected Pos getInitialAlignment() { return Pos.CENTER; } /*************************************************************************** * * * Accessibility handling * * * **************************************************************************/ /** {@inheritDoc} */ @Override public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) { switch (attribute) { case SELECTED: return isSelected(); default: return super.queryAccessibleAttribute(attribute, parameters); } } }