javafx.scene.layout.VBox Maven / Gradle / Ivy
/*
* Copyright (c) 2011, 2023, 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.layout;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.ObjectProperty;
import javafx.css.CssMetaData;
import javafx.css.StyleableBooleanProperty;
import javafx.css.StyleableDoubleProperty;
import javafx.css.StyleableObjectProperty;
import javafx.css.StyleableProperty;
import javafx.geometry.HPos;
import javafx.geometry.Insets;
import javafx.geometry.Orientation;
import javafx.geometry.Pos;
import javafx.geometry.VPos;
import javafx.scene.Node;
import javafx.css.converter.BooleanConverter;
import javafx.css.converter.EnumConverter;
import javafx.css.converter.SizeConverter;
import javafx.css.Styleable;
import javafx.util.Callback;
/**
* VBox lays out its children in a single vertical column.
* If the vbox has a border and/or padding set, then the contents will be laid
* out within those insets.
*
* VBox example:
*
{@code
* VBox vbox = new VBox(8); // spacing = 8
* vbox.getChildren().addAll(new Button("Cut"), new Button("Copy"), new Button("Paste"));
* }
*
* VBox will resize children (if resizable) to their preferred heights and uses its
* {@link #fillWidthProperty() fillWidth} property to determine whether to resize their widths to
* fill its own width or keep their widths to their preferred (fillWidth defaults to true).
* The alignment of the content is controlled by the {@link #alignmentProperty() alignment} property,
* which defaults to Pos.TOP_LEFT.
*
* If a vbox is resized larger than its preferred height, by default it will keep
* children to their preferred heights, leaving the extra space unused. If an
* application wishes to have one or more children be allocated that extra space
* it may optionally set a vgrow constraint on the child. See "Optional Layout
* Constraints" for details.
*
* VBox lays out each managed child regardless of the child's
* visible property value; unmanaged children are ignored.
*
* Resizable Range
*
*
* A vbox's parent will resize the vbox within the vbox's resizable range
* during layout. By default the vbox computes this range based on its content
* as outlined in the table below.
*
*
* VBox Resize Table
* width height minimum
* left/right insets plus the largest of the children's min widths.
* top/bottom insets plus the sum of each child's min height plus spacing between each child.
* preferred
* left/right insets plus the largest of the children's pref widths.
* top/bottom insets plus the sum of each child's pref height plus spacing between each child.
* maximum
* Double.MAX_VALUE Double.MAX_VALUE
*
* A vbox's unbounded maximum width and height are an indication to the parent that
* it may be resized beyond its preferred size to fill whatever space is assigned
* to it.
*
* VBox provides properties for setting the size range directly. These
* properties default to the sentinel value USE_COMPUTED_SIZE, however the
* application may set them to other values as needed:
*
* vbox.setPrefWidth(400);
*
* Applications may restore the computed values by setting these properties back
* to USE_COMPUTED_SIZE.
*
* VBox does not clip its content by default, so it is possible that children's
* bounds may extend outside its own bounds if a child's min size prevents it from
* being fit within the vbox.
*
* Optional Layout Constraints
*
*
* An application may set constraints on individual children to customize VBox's layout.
* For each constraint, VBox provides a static method for setting it on the child.
*
*
*
* VBox Constraint Table
* Constraint Type Description vgrow javafx.scene.layout.Priority The vertical grow priority for the child. margin javafx.geometry.Insets Margin space around the outside of the child.
*
* For example, if a vbox needs the ListView to be allocated all extra space:
*
* VBox vbox = new VBox();
* ListView list = new ListView();
* VBox.setVgrow(list, Priority.ALWAYS);
* vbox.getChildren().addAll(new Label("Names:"), list);
*
*
* If more than one child has the same grow priority set, then the vbox will
* allocate equal amounts of space to each. VBox will only grow a child up to
* its maximum height, so if the child has a max height other than Double.MAX_VALUE,
* the application may need to override the max to allow it to grow.
* @since JavaFX 2.0
*/
public class VBox extends Pane {
private boolean biasDirty = true;
private Orientation bias;
private double[][] tempArray;
/* ******************************************************************
* BEGIN static methods
********************************************************************/
private static final String MARGIN_CONSTRAINT = "vbox-margin";
private static final String VGROW_CONSTRAINT = "vbox-vgrow";
/**
* Sets the vertical grow priority for the child when contained by a vbox.
* If set, the vbox will use the priority value to allocate additional space if the
* vbox is resized larger than its preferred height.
* If multiple vbox children have the same vertical grow priority, then the
* extra space will be split evenly between them.
* If no vertical grow priority is set on a child, the vbox will never
* allocate any additional vertical space for that child.
*
* Setting the value to {@code null} will remove the constraint.
* @param child the child of a vbox
* @param value the vertical grow priority for the child
*/
public static void setVgrow(Node child, Priority value) {
setConstraint(child, VGROW_CONSTRAINT, value);
}
/**
* Returns the child's vgrow property if set.
* @param child the child node of a vbox
* @return the vertical grow priority for the child or null if no priority was set
*/
public static Priority getVgrow(Node child) {
return (Priority)getConstraint(child, VGROW_CONSTRAINT);
}
/**
* Sets the margin for the child when contained by a vbox.
* If set, the vbox will layout the child so that it has the margin space around it.
* Setting the value to null will remove the constraint.
* @param child the child mode of a vbox
* @param value the margin of space around the child
*/
public static void setMargin(Node child, Insets value) {
setConstraint(child, MARGIN_CONSTRAINT, value);
}
/**
* Returns the child's margin property if set.
* @param child the child node of a vbox
* @return the margin for the child or null if no margin was set
*/
public static Insets getMargin(Node child) {
return (Insets)getConstraint(child, MARGIN_CONSTRAINT);
}
private static final Callback marginAccessor = n -> getMargin(n);
/**
* Removes all vbox constraints from the child node.
* @param child the child node
*/
public static void clearConstraints(Node child) {
setVgrow(child, null);
setMargin(child, null);
}
/* ******************************************************************
* END static methods
********************************************************************/
/**
* Creates a {@code VBox} layout with {@code spacing = 0} and alignment at {@code TOP_LEFT}.
*/
public VBox() {
super();
}
/**
* Creates a {@code VBox} layout with the specified spacing between children.
* @param spacing the amount of vertical space between each child
*/
public VBox(double spacing) {
this();
setSpacing(spacing);
}
/**
* Creates a {@code VBox} layout with {@code spacing = 0}.
* @param children the initial set of children for this pane
* @since JavaFX 8.0
*/
public VBox(Node... children) {
super();
getChildren().addAll(children);
}
/**
* Creates a {@code VBox} layout with the specified spacing between children.
* @param spacing the amount of vertical space between each child
* @param children the initial set of children for this pane
* @since JavaFX 8.0
*/
public VBox(double spacing, Node... children) {
this();
setSpacing(spacing);
getChildren().addAll(children);
}
/**
* The amount of vertical space between each child in the vbox.
* @return the amount of vertical space between each child in the vbox
*/
public final DoubleProperty spacingProperty() {
if (spacing == null) {
spacing = new StyleableDoubleProperty() {
@Override
public void invalidated() {
requestLayout();
}
@Override
public Object getBean() {
return VBox.this;
}
@Override
public String getName() {
return "spacing";
}
@Override
public CssMetaData getCssMetaData() {
return StyleableProperties.SPACING;
}
};
}
return spacing;
}
private DoubleProperty spacing;
public final void setSpacing(double value) { spacingProperty().set(value); }
public final double getSpacing() { return spacing == null ? 0 : spacing.get(); }
/**
* The overall alignment of children within the vbox's width and height.
* @return the overall alignment of children within the vbox's width and
* height
*/
public final ObjectProperty alignmentProperty() {
if (alignment == null) {
alignment = new StyleableObjectProperty(Pos.TOP_LEFT) {
@Override
public void invalidated() {
requestLayout();
}
@Override
public Object getBean() {
return VBox.this;
}
@Override
public String getName() {
return "alignment";
}
@Override
public CssMetaData getCssMetaData() {
return StyleableProperties.ALIGNMENT;
}
};
}
return alignment;
}
private ObjectProperty alignment;
public final void setAlignment(Pos value) { alignmentProperty().set(value); }
public final Pos getAlignment() { return alignment == null ? Pos.TOP_LEFT : alignment.get(); }
private Pos getAlignmentInternal() {
Pos localPos = getAlignment();
return localPos == null ? Pos.TOP_LEFT : localPos;
}
/**
* Whether or not resizable children will be resized to fill the full width of the vbox
* or be resized to their preferred width and aligned according to the alignment
* hpos value.
* @return true if resizable children will be resized to fill the full width
* of the vbox
*/
public final BooleanProperty fillWidthProperty() {
if (fillWidth == null) {
fillWidth = new StyleableBooleanProperty(true) {
@Override
public void invalidated() {
requestLayout();
}
@Override
public Object getBean() {
return VBox.this;
}
@Override
public String getName() {
return "fillWidth";
}
@Override
public CssMetaData getCssMetaData() {
return StyleableProperties.FILL_WIDTH;
}
};
}
return fillWidth;
}
private BooleanProperty fillWidth;
public final void setFillWidth(boolean value) { fillWidthProperty().set(value); }
public final boolean isFillWidth() { return fillWidth == null ? true : fillWidth.get(); }
/**
*
* @return null unless one of its children has a content bias.
*/
@Override public Orientation getContentBias() {
if (biasDirty) {
bias = null;
final List children = getManagedChildren();
for (Node child : children) {
Orientation contentBias = child.getContentBias();
if (contentBias != null) {
bias = contentBias;
if (contentBias == Orientation.HORIZONTAL) {
break;
}
}
}
biasDirty = false;
}
return bias;
}
@Override protected double computeMinWidth(double height) {
Insets insets = getInsets();
Listmanaged = getManagedChildren();
double contentWidth = 0;
if (height != -1 && getContentBias() != null) {
double prefHeights[][] = getAreaHeights(managed, -1, false);
adjustAreaHeights(managed, prefHeights, height, -1);
contentWidth = computeMaxMinAreaWidth(managed, marginAccessor, prefHeights[0], false);
} else {
contentWidth = computeMaxMinAreaWidth(managed, marginAccessor);
}
return snapSpaceX(insets.getLeft()) + contentWidth + snapSpaceX(insets.getRight());
}
@Override protected double computeMinHeight(double width) {
Insets insets = getInsets();
return snapSpaceY(insets.getTop()) +
computeContentHeight(getManagedChildren(), width, true) +
snapSpaceY(insets.getBottom());
}
@Override protected double computePrefWidth(double height) {
Insets insets = getInsets();
Listmanaged = getManagedChildren();
double contentWidth = 0;
if (height != -1 && getContentBias() != null) {
double prefHeights[][] = getAreaHeights(managed, -1, false);
adjustAreaHeights(managed, prefHeights, height, -1);
contentWidth = computeMaxPrefAreaWidth(managed, marginAccessor, prefHeights[0], false);
} else {
contentWidth = computeMaxPrefAreaWidth(managed, marginAccessor);
}
return snapSpaceX(insets.getLeft()) + contentWidth + snapSpaceX(insets.getRight());
}
@Override protected double computePrefHeight(double width) {
Insets insets = getInsets();
double d = snapSpaceY(insets.getTop()) +
computeContentHeight(getManagedChildren(), width, false) +
snapSpaceY(insets.getBottom());
return d;
}
private double[][] getAreaHeights(Listmanaged, double width, boolean minimum) {
// width could be -1
double[][] temp = getTempArray(managed.size());
final double insideWidth = width == -1? -1 : width -
snapSpaceX(getInsets().getLeft()) - snapSpaceX(getInsets().getRight());
final boolean isFillWidth = isFillWidth();
for (int i = 0, size = managed.size(); i < size; i++) {
Node child = managed.get(i);
Insets margin = getMargin(child);
if (minimum) {
if (insideWidth != -1 && isFillWidth) {
temp[0][i] = computeChildMinAreaHeight(child, -1, margin, insideWidth);
} else {
temp[0][i] = computeChildMinAreaHeight(child, -1, margin, -1);
}
} else {
if (insideWidth != -1 && isFillWidth) {
temp[0][i] = computeChildPrefAreaHeight(child, -1, margin, insideWidth);
} else {
temp[0][i] = computeChildPrefAreaHeight(child, -1, margin, -1);
}
}
}
return temp;
}
private double adjustAreaHeights(Listmanaged, double areaHeights[][], double height, double width) {
Insets insets = getInsets();
double left = snapSpaceX(insets.getLeft());
double right = snapSpaceX(insets.getRight());
double contentHeight = sum(areaHeights[0], managed.size()) + (managed.size()-1)*snapSpaceY(getSpacing());
double extraHeight = height -
snapSpaceY(insets.getTop()) - snapSpaceY(insets.getBottom()) - contentHeight;
if (extraHeight != 0) {
final double refWidth = isFillWidth()&& width != -1? width - left - right : -1;
double remaining = growOrShrinkAreaHeights(managed, areaHeights, Priority.ALWAYS, extraHeight, refWidth);
remaining = growOrShrinkAreaHeights(managed, areaHeights, Priority.SOMETIMES, remaining, refWidth);
contentHeight += (extraHeight - remaining);
}
return contentHeight;
}
private double growOrShrinkAreaHeights(Listmanaged, double areaHeights[][], Priority priority, double extraHeight, double width) {
final boolean shrinking = extraHeight < 0;
int adjustingNumber = 0;
double[] usedHeights = areaHeights[0];
double[] temp = areaHeights[1];
if (shrinking) {
adjustingNumber = managed.size();
for (int i = 0, size = managed.size(); i < size; i++) {
final Node child = managed.get(i);
temp[i] = computeChildMinAreaHeight(child, -1, getMargin(child), width);
}
} else {
for (int i = 0, size = managed.size(); i < size; i++) {
final Node child = managed.get(i);
if (getVgrow(child) == priority) {
temp[i] = computeChildMaxAreaHeight(child, -1, getMargin(child), width);
adjustingNumber++;
} else {
temp[i] = -1;
}
}
}
double pixelSize = isSnapToPixel() ? 1 / Region.getSnapScaleY(this) : 0.0;
double available = extraHeight; // will be negative in shrinking case
outer: while (Math.abs(available) >= pixelSize && adjustingNumber > 0) {
double portion = snapPortionY(available / adjustingNumber); // negative in shrinking case
if (portion == 0) {
if (pixelSize == 0) {
break;
}
portion = pixelSize * Math.signum(available);
}
for (int i = 0, size = managed.size(); i < size; i++) {
if (temp[i] == -1) {
continue;
}
final double limit = temp[i] - usedHeights[i]; // negative in shrinking case
final double change = Math.abs(limit) <= Math.abs(portion)? limit : portion;
usedHeights[i] += change;
available -= change;
if (Math.abs(available) < pixelSize) {
break outer;
}
if (Math.abs(change) < Math.abs(portion)) {
temp[i] = -1;
adjustingNumber--;
}
}
}
return available; // might be negative in shrinking case
}
private double computeContentHeight(List managedChildren, double width, boolean minimum) {
return sum(getAreaHeights(managedChildren, width, minimum)[0], managedChildren.size())
+ (managedChildren.size()-1)*snapSpaceY(getSpacing());
}
private static double sum(double[] array, int size) {
int i = 0;
double res = 0;
while (i != size) {
res += array[i++];
}
return res;
}
@Override public void requestLayout() {
biasDirty = true;
bias = null;
super.requestLayout();
}
@Override protected void layoutChildren() {
List managed = getManagedChildren();
Insets insets = getInsets();
double width = getWidth();
double height = getHeight();
double top = snapSpaceY(insets.getTop());
double left = snapSpaceX(insets.getLeft());
double bottom = snapSpaceY(insets.getBottom());
double right = snapSpaceX(insets.getRight());
double space = snapSpaceY(getSpacing());
HPos hpos = getAlignmentInternal().getHpos();
VPos vpos = getAlignmentInternal().getVpos();
boolean isFillWidth = isFillWidth();
double[][] actualAreaHeights = getAreaHeights(managed, width, false);
double contentWidth = width - left - right;
double contentHeight = adjustAreaHeights(managed, actualAreaHeights, height, width);
double x = left;
double y = top + computeYOffset(height - top - bottom, contentHeight, vpos);
for (int i = 0, size = managed.size(); i < size; i++) {
Node child = managed.get(i);
layoutInArea(child, x, y, contentWidth, actualAreaHeights[0][i],
/* baseline shouldn't matter */actualAreaHeights[0][i],
getMargin(child), isFillWidth, true,
hpos, vpos);
y += actualAreaHeights[0][i] + space;
}
}
private double[][] getTempArray(int size) {
if (tempArray == null) {
tempArray = new double[2][size]; // First array for the result, second for temporary computations
} else if (tempArray[0].length < size) {
tempArray = new double[2][Math.max(tempArray.length * 3, size)];
}
return tempArray;
}
/* *************************************************************************
* *
* Stylesheet Handling *
* *
**************************************************************************/
/*
* Super-lazy instantiation pattern from Bill Pugh.
*/
private static class StyleableProperties {
private static final CssMetaData ALIGNMENT =
new CssMetaData<>("-fx-alignment",
new EnumConverter<>(Pos.class), Pos.TOP_LEFT){
@Override
public boolean isSettable(VBox node) {
return node.alignment == null || !node.alignment.isBound();
}
@Override
public StyleableProperty getStyleableProperty(VBox node) {
return (StyleableProperty)node.alignmentProperty();
}
};
private static final CssMetaData FILL_WIDTH =
new CssMetaData<>("-fx-fill-width",
BooleanConverter.getInstance(), Boolean.TRUE) {
@Override
public boolean isSettable(VBox node) {
return node.fillWidth == null || !node.fillWidth.isBound();
}
@Override
public StyleableProperty getStyleableProperty(VBox node) {
return (StyleableProperty)node.fillWidthProperty();
}
};
private static final CssMetaData SPACING =
new CssMetaData<>("-fx-spacing",
SizeConverter.getInstance(), 0d) {
@Override
public boolean isSettable(VBox node) {
return node.spacing == null || !node.spacing.isBound();
}
@Override
public StyleableProperty getStyleableProperty(VBox node) {
return (StyleableProperty)node.spacingProperty();
}
};
private static final List> STYLEABLES;
static {
final List> styleables =
new ArrayList<>(Region.getClassCssMetaData());
styleables.add(ALIGNMENT);
styleables.add(FILL_WIDTH);
styleables.add(SPACING);
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> getCssMetaData() {
return getClassCssMetaData();
}
}