javafx.scene.control.ScrollBar Maven / Gradle / Ivy
/*
* Copyright (c) 2010, 2022, 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.control.Properties;
import com.sun.javafx.util.Utils;
import javafx.css.converter.EnumConverter;
import javafx.css.converter.SizeConverter;
import javafx.scene.control.skin.ScrollBarSkin;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleDoubleProperty;
import javafx.beans.value.WritableValue;
import javafx.css.CssMetaData;
import javafx.css.PseudoClass;
import javafx.css.Styleable;
import javafx.css.StyleableDoubleProperty;
import javafx.css.StyleableObjectProperty;
import javafx.css.StyleableProperty;
import javafx.geometry.Orientation;
import javafx.scene.AccessibleAction;
import javafx.scene.AccessibleAttribute;
import javafx.scene.AccessibleRole;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* Either a horizontal or vertical bar with increment and decrement buttons and
* a "thumb" with which the user can interact. Typically not used alone but used
* for building up more complicated controls such as the ScrollPane and ListView.
*
* ScrollBar sets focusTraversable to false.
*
*
*
* This example creates a vertical ScrollBar:
*
ScrollBar s1 = new ScrollBar();
* s1.setOrientation(Orientation.VERTICAL);
*
* 
*
* @since JavaFX 2.0
*/
public class ScrollBar extends Control {
/* *************************************************************************
* *
* Constructors *
* *
**************************************************************************/
/**
* Creates a new horizontal ScrollBar (ie getOrientation() == Orientation.HORIZONTAL).
*
*
*/
public ScrollBar() {
// TODO : we need to ensure we have a width and height
setWidth(Properties.DEFAULT_WIDTH);
setHeight(Properties.DEFAULT_LENGTH);
getStyleClass().setAll(DEFAULT_STYLE_CLASS);
setAccessibleRole(AccessibleRole.SCROLL_BAR);
// focusTraversable is styleable through css. Calling setFocusTraversable
// makes it look to css like the user set the value and css will not
// override. Initializing focusTraversable by calling applyStyle with null
// for StyleOrigin ensures that css will be able to override the value.
((StyleableProperty)focusTraversableProperty()).applyStyle(null,Boolean.FALSE);
// set pseudo-class state to horizontal
pseudoClassStateChanged(HORIZONTAL_PSEUDOCLASS_STATE, true);
}
/* *************************************************************************
* *
* Properties *
* *
**************************************************************************/
/**
* The minimum value represented by this {@code ScrollBar}. This should be a
* value less than or equal to {@link #maxProperty max}. Default value is 0.
*/
private DoubleProperty min;
public final void setMin(double value) {
minProperty().set(value);
}
public final double getMin() {
return min == null ? 0 : min.get();
}
public final DoubleProperty minProperty() {
if (min == null) {
min = new SimpleDoubleProperty(this, "min");
}
return min;
}
/**
* The maximum value represented by this {@code ScrollBar}. This should be a
* value greater than or equal to {@link #minProperty min}. Default value is 100.
*/
private DoubleProperty max;
public final void setMax(double value) {
maxProperty().set(value);
}
public final double getMax() {
return max == null ? 100 : max.get();
}
public final DoubleProperty maxProperty() {
if (max == null) {
max = new SimpleDoubleProperty(this, "max", 100);
}
return max;
}
/**
* The current value represented by this {@code ScrollBar}. This value should
* be between {@link #minProperty min} and {@link #maxProperty max}, inclusive.
*/
private DoubleProperty value;
public final void setValue(double value) {
valueProperty().set(value);
}
public final double getValue() {
return value == null ? 0 : value.get();
}
public final DoubleProperty valueProperty() {
if (value == null) {
value = new SimpleDoubleProperty(this, "value");
}
return value;
}
/**
* The orientation of the {@code ScrollBar} can either be {@link javafx.geometry.Orientation#HORIZONTAL HORIZONTAL}
* or {@link javafx.geometry.Orientation#VERTICAL VERTICAL}.
*/
private ObjectProperty orientation;
public final void setOrientation(Orientation value) {
orientationProperty().set(value);
}
public final Orientation getOrientation() {
return orientation == null ? Orientation.HORIZONTAL : orientation.get();
}
public final ObjectProperty orientationProperty() {
if (orientation == null) {
orientation = new StyleableObjectProperty(Orientation.HORIZONTAL) {
@Override protected void invalidated() {
final boolean vertical = (get() == Orientation.VERTICAL);
pseudoClassStateChanged(VERTICAL_PSEUDOCLASS_STATE, vertical);
pseudoClassStateChanged(HORIZONTAL_PSEUDOCLASS_STATE, !vertical);
}
@Override
public CssMetaData getCssMetaData() {
return StyleableProperties.ORIENTATION;
}
@Override
public Object getBean() {
return ScrollBar.this;
}
@Override
public String getName() {
return "orientation";
}
};
}
return orientation;
}
/**
* The amount by which to adjust the ScrollBar when the {@link #increment() increment} or
* {@link #decrement() decrement} methods are called.
*/
private DoubleProperty unitIncrement;
public final void setUnitIncrement(double value) {
unitIncrementProperty().set(value);
}
public final double getUnitIncrement() {
return unitIncrement == null ? 1 : unitIncrement.get();
}
public final DoubleProperty unitIncrementProperty() {
if (unitIncrement == null) {
unitIncrement = new StyleableDoubleProperty(1) {
@Override
public CssMetaData getCssMetaData() {
return StyleableProperties.UNIT_INCREMENT;
}
@Override
public Object getBean() {
return ScrollBar.this;
}
@Override
public String getName() {
return "unitIncrement";
}
};
}
return unitIncrement;
}
/**
* The amount by which to adjust the scrollbar if the track of the bar is
* clicked.
*/
private DoubleProperty blockIncrement;
public final void setBlockIncrement(double value) {
blockIncrementProperty().set(value);
}
public final double getBlockIncrement() {
return blockIncrement == null ? 10 : blockIncrement.get();
}
public final DoubleProperty blockIncrementProperty() {
if (blockIncrement == null) {
blockIncrement = new StyleableDoubleProperty(10) {
@Override
public CssMetaData getCssMetaData() {
return StyleableProperties.BLOCK_INCREMENT;
}
@Override
public Object getBean() {
return ScrollBar.this;
}
@Override
public String getName() {
return "blockIncrement";
}
};
}
return blockIncrement;
}
/**
* Visible amount of the scrollbar's range, typically represented by
* the size of the scroll bar's thumb.
*/
private DoubleProperty visibleAmount;
public final void setVisibleAmount(double value) {
visibleAmountProperty().set(value);
}
public final double getVisibleAmount() {
return visibleAmount == null ? 15 : visibleAmount.get();
}
public final DoubleProperty visibleAmountProperty() {
if (visibleAmount == null) {
visibleAmount = new SimpleDoubleProperty(this, "visibleAmount");
}
return visibleAmount;
}
/* *************************************************************************
* *
* Methods *
* *
**************************************************************************/
/**
* Adjusts the {@link #valueProperty() value} property by
* {@link #blockIncrementProperty() blockIncrement}. The {@code position} is the fractional amount
* between the {@link #minProperty min} and {@link #maxProperty max}. For
* example, it might be 50%. If {@code #minProperty min} were 0 and {@code #maxProperty max}
* were 100 and {@link #valueProperty() value} were 25, then a position of .5 would indicate
* that we should increment {@link #valueProperty() value} by
* {@code blockIncrement}. If {@link #valueProperty() value} were 75, then a
* position of .5 would indicate that we
* should decrement {@link #valueProperty() value} by {@link #blockIncrementProperty blockIncrement}.
*
* 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.
* @param position the position
*/
public void adjustValue(double position) {
// figure out the "value" associated with the specified position
double posValue = ((getMax() - getMin()) * Utils.clamp(0, position, 1))+getMin();
double newValue;
if (Double.compare(posValue, getValue()) != 0) {
if (posValue > getValue()) {
newValue = getValue() + getBlockIncrement();
}
else {
newValue = getValue() - getBlockIncrement();
}
setValue(Utils.clamp(getMin(), newValue, getMax()));
}
}
/**
* Increments the value of the {@code ScrollBar} by the
* {@link #unitIncrementProperty unitIncrement}
*/
public void increment() {
setValue(Utils.clamp(getMin(), getValue() + getUnitIncrement(), getMax()));
}
/**
* Decrements the value of the {@code ScrollBar} by the
* {@link #unitIncrementProperty unitIncrement}
*/
public void decrement() {
setValue(Utils.clamp(getMin(), getValue() - getUnitIncrement(), getMax()));
}
private void blockIncrement() {
adjustValue(getValue() + getBlockIncrement());
}
private void blockDecrement() {
adjustValue(getValue() - getBlockIncrement());
}
/** {@inheritDoc} */
@Override protected Skin createDefaultSkin() {
return new ScrollBarSkin(this);
}
/* *************************************************************************
* *
* Stylesheet Handling *
* *
**************************************************************************/
/**
* Initialize the style class to 'scroll-bar'.
*
* This is the selector class from which CSS can be used to style
* this control.
*/
private static final String DEFAULT_STYLE_CLASS = "scroll-bar";
private static class StyleableProperties {
private static final CssMetaData ORIENTATION =
new CssMetaData<>("-fx-orientation",
new EnumConverter<>(Orientation.class),
Orientation.HORIZONTAL) {
@Override
public Orientation getInitialValue(ScrollBar node) {
// A vertical ScrollBar should remain vertical
return node.getOrientation();
}
@Override
public boolean isSettable(ScrollBar n) {
return n.orientation == null || !n.orientation.isBound();
}
@Override
public StyleableProperty getStyleableProperty(ScrollBar n) {
return (StyleableProperty)(WritableValue)n.orientationProperty();
}
};
private static final CssMetaData UNIT_INCREMENT =
new CssMetaData<>("-fx-unit-increment",
SizeConverter.getInstance(), 1.0) {
@Override
public boolean isSettable(ScrollBar n) {
return n.unitIncrement == null || !n.unitIncrement.isBound();
}
@Override
public StyleableProperty getStyleableProperty(ScrollBar n) {
return (StyleableProperty)n.unitIncrementProperty();
}
};
private static final CssMetaData BLOCK_INCREMENT =
new CssMetaData<>("-fx-block-increment",
SizeConverter.getInstance(), 10.0) {
@Override
public boolean isSettable(ScrollBar n) {
return n.blockIncrement == null || !n.blockIncrement.isBound();
}
@Override
public StyleableProperty getStyleableProperty(ScrollBar n) {
return (StyleableProperty)n.blockIncrementProperty();
}
};
private static final List> STYLEABLES;
static {
final List> styleables =
new ArrayList<>(Control.getClassCssMetaData());
styleables.add(ORIENTATION);
styleables.add(UNIT_INCREMENT);
styleables.add(BLOCK_INCREMENT);
STYLEABLES = Collections.unmodifiableList(styleables);
}
}
/**
* Gets the {@code CssMetaData} associated with this class, which may include the
* {@code CssMetaData} of its superclasses.
* @return the {@code CssMetaData}
* @since JavaFX 8.0
*/
public static List> getClassCssMetaData() {
return StyleableProperties.STYLEABLES;
}
/**
* {@inheritDoc}
* @since JavaFX 8.0
*/
@Override
public List> getControlCssMetaData() {
return getClassCssMetaData();
}
/**
* Pseud-class indicating this is a vertical ScrollBar.
*/
private static final PseudoClass VERTICAL_PSEUDOCLASS_STATE =
PseudoClass.getPseudoClass("vertical");
/**
* Pseudo-class indicating this is a horizontal ScrollBar.
*/
private static final PseudoClass HORIZONTAL_PSEUDOCLASS_STATE =
PseudoClass.getPseudoClass("horizontal");
/**
* Returns the initial focus traversable state of this control, for use
* by the JavaFX CSS engine to correctly set its initial value. This method
* is overridden as by default UI controls have focus traversable set to true,
* but that is not appropriate for this control.
*
* @since 9
*/
@Override protected Boolean getInitialFocusTraversable() {
return Boolean.FALSE;
}
/* *************************************************************************
* *
* Accessibility handling *
* *
**************************************************************************/
/** {@inheritDoc} */
@Override
public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) {
switch (attribute) {
case VALUE: return getValue();
case MAX_VALUE: return getMax();
case MIN_VALUE: return getMin();
case ORIENTATION: return getOrientation();
default: return super.queryAccessibleAttribute(attribute, parameters);
}
}
/** {@inheritDoc} */
@Override
public void executeAccessibleAction(AccessibleAction action, Object... parameters) {
switch (action) {
case INCREMENT: increment(); break;
case DECREMENT: decrement(); break;
case BLOCK_INCREMENT: blockIncrement(); break;
case BLOCK_DECREMENT: blockDecrement(); break;
case SET_VALUE: {
Double value = (Double) parameters[0];
if (value != null) setValue(value);
break;
}
default: super.executeAccessibleAction(action, parameters);
}
}
}