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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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).
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package javafx.scene.control;

import javafx.beans.property.BooleanProperty;
import javafx.beans.property.BooleanPropertyBase;
import javafx.beans.property.SimpleBooleanProperty;

import javafx.event.ActionEvent;
import javafx.geometry.Pos;
import javafx.css.PseudoClass;
import javafx.scene.AccessibleAttribute;
import javafx.scene.AccessibleRole;
import javafx.scene.control.skin.CheckBoxSkin;

A tri-state selection Control typically skinned as a box with a checkmark or
tick mark when checked. A CheckBox control can be in one of three states:

 
checked: indeterminate == false, checked == true
 
unchecked: indeterminate == false, checked == false
 
undefined: indeterminate == true

If a CheckBox is checked, then it is also by definition defined. When
checked the CheckBox is typically rendered with a "check" or "tick" mark.
A CheckBox is in this state if selected is true and indeterminate is false.

A CheckBox is unchecked if selected is false and indeterminate is false.

A CheckBox is undefined if indeterminate is true, regardless of the state
of selected. A typical rendering would be with a minus or dash, to
indicate an undefined or indeterminate state of the CheckBox.
This is convenient for constructing tri-state checkbox
based trees, for example, where undefined check boxes typically mean "inherit
settings from the parent".

The allowIndeterminate variable, if true, allows the user
to cycle through the undefined state. If false, the CheckBox is
not in the indeterminate state, and the user is allowed to change only the checked
state.
Example:
CheckBox cb = new CheckBox("a checkbox");
cb.setIndeterminate(false);

MnemonicParsing is enabled by default for CheckBox.

Since:
JavaFX 2.0/**
 * A tri-state selection Control typically skinned as a box with a checkmark or
 * tick mark when checked. A CheckBox control can be in one of three states:
 * <ul>
 *  <li><em>checked</em>: indeterminate == false, checked == true</li>
 *  <li><em>unchecked</em>: indeterminate == false, checked == false</li>
 *  <li><em>undefined</em>: indeterminate == true</li>
 * </ul>
 * If a CheckBox is checked, then it is also by definition defined. When
 * checked the CheckBox is typically rendered with a "check" or "tick" mark.
 * A CheckBox is in this state if selected is true and indeterminate is false.
 * <p>
 * A CheckBox is unchecked if selected is false and indeterminate is false.
 * <p>
 * A CheckBox is undefined if indeterminate is true, regardless of the state
 * of selected. A typical rendering would be with a minus or dash, to
 * indicate an undefined or indeterminate state of the CheckBox.
 * This is convenient for constructing tri-state checkbox
 * based trees, for example, where undefined check boxes typically mean "inherit
 * settings from the parent".
 * <p>
 * The allowIndeterminate variable, if true, allows the user
 * to cycle through the undefined state. If false, the CheckBox is
 * not in the indeterminate state, and the user is allowed to change only the checked
 * state.
 *
 * <p>Example:
 * <pre><code>CheckBox cb = new CheckBox("a checkbox");
 * cb.setIndeterminate(false);</code></pre>
 *
 * <p>
 * MnemonicParsing is enabled by default for CheckBox.
 * </p>
 *
 * @since JavaFX 2.0
 */

public class CheckBox extends ButtonBase {

    /***************************************************************************
     *                                                                         *
     * Constructors                                                            *
     *                                                                         *
     **************************************************************************/

    
Creates a check box with an empty string for its label.
/**
     * Creates a check box with an empty string for its label.
     */
    public CheckBox() {
        initialize();
    }

    
Creates a check box with the specified text as its label.
Params:
text – A text string for its label./**
     * Creates a check box with the specified text as its label.
     *
     * @param text A text string for its label.
     */
    public CheckBox(String text) {
        setText(text);
        initialize();
    }

    private void initialize() {
        getStyleClass().setAll(DEFAULT_STYLE_CLASS);
        setAccessibleRole(AccessibleRole.CHECK_BOX);
        setAlignment(Pos.CENTER_LEFT);
        setMnemonicParsing(true);     // enable mnemonic auto-parsing by default

        // initialize pseudo-class state
        pseudoClassStateChanged(PSEUDO_CLASS_DETERMINATE, true);
    }

    /***************************************************************************
     *                                                                         *
     * Properties                                                              *
     *                                                                         *
     **************************************************************************/
    
Determines whether the CheckBox is in the indeterminate state.
/**
     * Determines whether the CheckBox is in the indeterminate state.
     */
    private BooleanProperty indeterminate;
    public final void setIndeterminate(boolean value) {
        indeterminateProperty().set(value);
    }

    public final boolean isIndeterminate() {
        return indeterminate == null ? false : indeterminate.get();
    }

    public final BooleanProperty indeterminateProperty() {
        if (indeterminate == null) {
            indeterminate = new BooleanPropertyBase(false) {
                @Override protected void invalidated() {
                    final boolean active = get();
                    pseudoClassStateChanged(PSEUDO_CLASS_DETERMINATE,  !active);
                    pseudoClassStateChanged(PSEUDO_CLASS_INDETERMINATE, active);
                    notifyAccessibleAttributeChanged(AccessibleAttribute.INDETERMINATE);
                }

                @Override
                public Object getBean() {
                    return CheckBox.this;
                }

                @Override
                public String getName() {
                    return "indeterminate";
                }
            };
        }
        return indeterminate;
    }
    
Indicates whether this CheckBox is checked.
/**
     * Indicates whether this CheckBox is checked.
     */
    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 v = get();
                    pseudoClassStateChanged(PSEUDO_CLASS_SELECTED, v);
                    notifyAccessibleAttributeChanged(AccessibleAttribute.SELECTED);
                }

                @Override
                public Object getBean() {
                    return CheckBox.this;
                }

                @Override
                public String getName() {
                    return "selected";
                }
            };
        }
        return selected;
    }
    
Determines whether the user toggling the CheckBox should cycle through
all three states: checked, unchecked, and
undefined. If true then all three states will be cycled through; if false then only checked and
unchecked will be cycled.
/**
     * Determines whether the user toggling the CheckBox should cycle through
     * all three states: <em>checked</em>, <em>unchecked</em>, and
     * <em>undefined</em>. If {@code true} then all three states will be
     * cycled through; if {@code false} then only <em>checked</em> and
     * <em>unchecked</em> will be cycled.
     */
    private BooleanProperty allowIndeterminate;

    public final void setAllowIndeterminate(boolean value) {
        allowIndeterminateProperty().set(value);
    }

    public final boolean isAllowIndeterminate() {
        return allowIndeterminate == null ? false : allowIndeterminate.get();
    }

    public final BooleanProperty allowIndeterminateProperty() {
        if (allowIndeterminate == null) {
            allowIndeterminate =
                    new SimpleBooleanProperty(this, "allowIndeterminate");
        }
        return allowIndeterminate;
    }

    /***************************************************************************
     *                                                                         *
     * Methods                                                                 *
     *                                                                         *
     **************************************************************************/

    
Toggles the state of the CheckBox. If allowIndeterminate is true, then each invocation of this function will advance the CheckBox through the states checked, unchecked, and undefined. If allowIndeterminate is false, then the CheckBox will only cycle through the checked and unchecked states, and forcing indeterminate to equal to false. /**
     * Toggles the state of the {@code CheckBox}. If allowIndeterminate is
     * true, then each invocation of this function will advance the CheckBox
     * through the states checked, unchecked, and undefined. If
     * allowIndeterminate is false, then the CheckBox will only cycle through
     * the checked and unchecked states, and forcing indeterminate to equal to
     * false.
     */
    @Override public void fire() {
        if (!isDisabled()) {
            if (isAllowIndeterminate()) {
                if (!isSelected() && !isIndeterminate()) {
                    setIndeterminate(true);
                } else if (isSelected() && !isIndeterminate()) {
                    setSelected(false);
                } else if (isIndeterminate()) {
                    setSelected(true);
                    setIndeterminate(false);
                }
            } else {
                setSelected(!isSelected());
                setIndeterminate(false);
            }
            fireEvent(new ActionEvent());
        }
    }

    
{@inheritDoc} /** {@inheritDoc} */
    @Override protected Skin<?> createDefaultSkin() {
        return new CheckBoxSkin(this);
    }


    
                                                                        *
Stylesheet Handling                                                     *
                                                                        *
/***************************************************************************
     *                                                                         *
     * Stylesheet Handling                                                     *
     *                                                                         *
     **************************************************************************/

    private static final String DEFAULT_STYLE_CLASS = "check-box";
    private static final PseudoClass PSEUDO_CLASS_DETERMINATE =
            PseudoClass.getPseudoClass("determinate");
    private static final PseudoClass PSEUDO_CLASS_INDETERMINATE =
            PseudoClass.getPseudoClass("indeterminate");
    private static final PseudoClass PSEUDO_CLASS_SELECTED =
            PseudoClass.getPseudoClass("selected");


    /***************************************************************************
     *                                                                         *
     * Accessibility handling                                                  *
     *                                                                         *
     **************************************************************************/

    
{@inheritDoc} /** {@inheritDoc} */
    @Override
    public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) {
        switch (attribute) {
            case SELECTED: return isSelected();
            case INDETERMINATE: return isIndeterminate();
            default: return super.queryAccessibleAttribute(attribute, parameters);
        }
    }
}