Background

java.lang.Object
- javafx.scene.layout.Background

```
public final class Background
extends java.lang.Object
```
The Background of a Region. A Background is an immutable object which encapsulates the entire set of data required to render the background of a Region. Because this class is immutable, you can freely reuse the same Background on many different Regions. Please refer to JavaFX CSS Reference Guide for a complete description of the CSS rules for styling the background of a Region.
Every Background is comprised of fills and / or images. Neither list will ever be null, but either or both may be empty. Each defined BackgroundFill is rendered in order, followed by each defined BackgroundImage.
The Background's outsets define any extension of the drawing area of a Region which is necessary to account for all background drawing. These outsets are strictly defined by the BackgroundFills that are specified on this Background, if any, because all BackgroundImages are clipped to the drawing area, and do not define it. The outsets values are strictly non-negative.

Since:

JavaFX 8.0

Field Summary

Fields
Modifier and Type	Field and Description
`(package private) static <any>`	`BACKGROUND_COLOR`
`(package private) static <any>`	`BACKGROUND_IMAGE`
`(package private) static <any>`	`BACKGROUND_INSETS`
`(package private) static <any>`	`BACKGROUND_POSITION`
`(package private) static <any>`	`BACKGROUND_RADIUS`
`(package private) static <any>`	`BACKGROUND_REPEAT`
`(package private) static <any>`	`BACKGROUND_SIZE`
`static Background`	`EMPTY` An empty Background, useful to use instead of null.
`(package private) java.util.List<BackgroundFill>`	`fills`
`private int`	`hash` The cached hash code computation for the Background.
`private boolean`	`hasOpaqueFill` Specifies whether the Background has at least one opaque fill.
`(package private) boolean`	`hasPercentageBasedFills` True if there are any fills that are in some way based on the size of the region.
`(package private) boolean`	`hasPercentageBasedOpaqueFills`
`(package private) java.util.List<BackgroundImage>`	`images`
`private double`	`opaqueFillBottom` Package-private immutable fields referring to the opaque insets of this Background.
`private double`	`opaqueFillLeft` Package-private immutable fields referring to the opaque insets of this Background.
`private double`	`opaqueFillRight` Package-private immutable fields referring to the opaque insets of this Background.
`private double`	`opaqueFillTop` Package-private immutable fields referring to the opaque insets of this Background.
`(package private) Insets`	`outsets`
`private static java.util.List<<any>>`	`STYLEABLES`

Constructor Summary

Constructors
Constructor and Description
`Background(BackgroundFill... fills)` Create a new Background by supplying an array of BackgroundFills.
`Background(BackgroundFill[] fills, BackgroundImage[] images)` Create a new Background by supplying two arrays, one for background fills, and one for background images.
`Background(BackgroundImage... images)` Create a new Background by supplying an array of BackgroundImages.
`Background(java.util.List<BackgroundFill> fills, java.util.List<BackgroundImage> images)` Create a new Background supply two Lists, one for background fills and one for background images.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`private void`	`computeOpaqueInsets(double width, double height, boolean firstTime, double[] trbl)` Computes the opaque insets.
`(package private) void`	`computeOpaqueInsets(double width, double height, double[] trbl)` Computes the opaque insets for a region with the specified width and height.
`boolean`	`equals(java.lang.Object o)`
`static java.util.List<<any>>`	`getClassCssMetaData()`
`java.util.List<BackgroundFill>`	`getFills()` The list of BackgroundFills which together define the filled portion of this Background.
`java.util.List<BackgroundImage>`	`getImages()` The list of BackgroundImages which together define the image portion of this Background.
`Insets`	`getOutsets()` The outsets of this Background.
`int`	`hashCode()`
`boolean`	`isEmpty()` Gets whether the background is empty.
`boolean`	`isFillPercentageBased()` Gets whether the fill of this Background is based on percentages (that is, relative to the size of the region being styled).

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - BACKGROUND_COLOR
```
static final <any> BACKGROUND_COLOR
```
  - BACKGROUND_RADIUS
```
static final <any> BACKGROUND_RADIUS
```
  - BACKGROUND_INSETS
```
static final <any> BACKGROUND_INSETS
```
  - BACKGROUND_IMAGE
```
static final <any> BACKGROUND_IMAGE
```
  - BACKGROUND_REPEAT
```
static final <any> BACKGROUND_REPEAT
```
  - BACKGROUND_POSITION
```
static final <any> BACKGROUND_POSITION
```
  - BACKGROUND_SIZE
```
static final <any> BACKGROUND_SIZE
```
  - STYLEABLES
```
private static final java.util.List<<any>> STYLEABLES
```
  - EMPTY
```
public static final Background EMPTY
```
    An empty Background, useful to use instead of null.
  - fills
```
final java.util.List<BackgroundFill> fills
```
  - images
```
final java.util.List<BackgroundImage> images
```
  - outsets
```
final Insets outsets
```
  - hasOpaqueFill
```
private final boolean hasOpaqueFill
```
    Specifies whether the Background has at least one opaque fill.
  - opaqueFillTop
```
private final double opaqueFillTop
```
    Package-private immutable fields referring to the opaque insets of this Background.
  - opaqueFillRight
```
private final double opaqueFillRight
```
    Package-private immutable fields referring to the opaque insets of this Background.
  - opaqueFillBottom
```
private final double opaqueFillBottom
```
    Package-private immutable fields referring to the opaque insets of this Background.
  - opaqueFillLeft
```
private final double opaqueFillLeft
```
    Package-private immutable fields referring to the opaque insets of this Background.
  - hasPercentageBasedOpaqueFills
```
final boolean hasPercentageBasedOpaqueFills
```
  - hasPercentageBasedFills
```
final boolean hasPercentageBasedFills
```
    True if there are any fills that are in some way based on the size of the region. For example, if a CornerRadii on the fill is percentage based in either or both dimensions.
  - hash
```
private final int hash
```
    The cached hash code computation for the Background. One very big reason for making Background immutable was to make it possible to cache and reuse the same Background instance for multiple Regions (for example, every un-hovered Button should have the same Background instance). To enable efficient caching, we cache the hash.
- Constructor Detail
  - Background
```
public Background(BackgroundFill... fills)
```
    Create a new Background by supplying an array of BackgroundFills. This array may be null, or may contain null values. Any null values will be ignored and will not contribute to the fills or outsets.
    
    Parameters:
    
    fills - The fills. This may be null, and may contain nulls. Any contained nulls are filtered out and not included in the final List of fills. A null array becomes an empty List.
  - Background
```
public Background(BackgroundImage... images)
```
    Create a new Background by supplying an array of BackgroundImages. This array may be null, or may contain null values. Any null values will be ignored and will not contribute to the images.
    
    Parameters:
    
    images - The images. This may be null, and may contain nulls. Any contained nulls are filtered out and not included in the final List of images. A null array becomes an empty List.
  - Background
```
public Background(java.util.List<BackgroundFill> fills,
                  java.util.List<BackgroundImage> images)
```
    Create a new Background supply two Lists, one for background fills and one for background images. Either list may be null, and may contain nulls. Any null values in these lists will be ignored and will not contribute to the fills, images, or outsets.
    
    Parameters:
    
    fills - The fills. This may be null, and may contain nulls. Any contained nulls are filtered out and not included in the final List of fills. A null List becomes an empty List.
    
    images - The images. This may be null, and may contain nulls. Any contained nulls are filtered out and not included in the final List of images. A null List becomes an empty List.
  - Background
```
public Background(BackgroundFill[] fills,
                  BackgroundImage[] images)
```
    Create a new Background by supplying two arrays, one for background fills, and one for background images. Either array may be null, and may contain null values. Any null values in these arrays will be ignored and will not contribute to the fills, images, or outsets.
    
    Parameters:
    
    fills - The fills. This may be null, and may contain nulls. Any contained nulls are filtered out and not included in the final List of fills. A null array becomes an empty List.
    
    images - The images. This may be null, and may contain nulls. Any contained nulls are filtered out and not included in the final List of images. A null array becomes an empty List.
- Method Detail
  - getClassCssMetaData
```
public static java.util.List<<any>> getClassCssMetaData()
```
    Returns:
    
    The CssMetaData associated with this class, which may include the CssMetaData of its superclasses.
  - getFills
```
public final java.util.List<BackgroundFill> getFills()
```
    The list of BackgroundFills which together define the filled portion of this Background. This List is unmodifiable and immutable. It will never be null. The elements of this list will also never be null.
    
    Returns:
    
    the list of BackgroundFills
  - getImages
```
public final java.util.List<BackgroundImage> getImages()
```
    The list of BackgroundImages which together define the image portion of this Background. This List is unmodifiable and immutable. It will never be null. The elements of this list will also never be null.
    
    Returns:
    
    the list of BackgroundImages
  - getOutsets
```
public final Insets getOutsets()
```
    The outsets of this Background. This represents the largest bounding rectangle within which all drawing for the Background will take place. The outsets will never be negative, and represent the distance from the edge of the Region outward. Any BackgroundImages which would extend beyond the outsets will be clipped. Only the BackgroundFills contribute to the outsets.
    
    Returns:
    
    the outsets
  - isEmpty
```
public final boolean isEmpty()
```
    Gets whether the background is empty. It is empty if there are no fills or images.
    
    Returns:
    
    true if the Background is empty, false otherwise.
  - isFillPercentageBased
```
public boolean isFillPercentageBased()
```
    Gets whether the fill of this Background is based on percentages (that is, relative to the size of the region being styled). Specifically, this returns true if any of the CornerRadii on any of the fills on this Background has a radius that is based on percentages.
    
    Returns:
    
    True if any CornerRadii of any BackgroundFill on this background would return true, false otherwise.
    
    Since:
    
    JavaFX 8.0
  - computeOpaqueInsets
```
void computeOpaqueInsets(double width,
                         double height,
                         double[] trbl)
```
    Computes the opaque insets for a region with the specified width and height. This call must be made whenever the width or height of the region change, because the opaque insets are based on background fills, and the corner radii of a background fill can be percentage based. Thus, we need to potentially recompute the opaque insets whenever the width or height of the region change. On the other hand, if there are no percentage based corner radii, then we can simply return the pre-computed and cached answers.
    
    Parameters:
    
    width - The width of the region
    
    height - The height of the region
    
    trbl - A four-element array of doubles in order: top, right, bottom, left.
  - computeOpaqueInsets
```
private void computeOpaqueInsets(double width,
                                 double height,
                                 boolean firstTime,
                                 double[] trbl)
```
    Computes the opaque insets. The first time this is called from the constructor we want to take the long route through and compute everything, whether there are percentage based insets or not (the constructor ensures not to call it in the case that it has percentage based insets!). All other times, this is called by the other computeOpaqueInsets method with "firstTime" set to false, such that if we have percentage based insets, then we will bail early. This method takes into account both fills and images. Because images can be lazy loaded, we cannot pre-compute a bunch of things in the constructor for images the way we can with fills. Instead, each time the method is called, we have to inspect the images. However, we do have fast paths for cases where fills are used and not images.
    
    Parameters:
    
    width - The width of the region
    
    height - The height of the region
    
    firstTime - Whether this is being called from the constructor
    
    trbl - A four-element array of doubles in order: top, right, bottom, left.
  - equals
```
public boolean equals(java.lang.Object o)
```
    Overrides:
    
    equals in class java.lang.Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object

Class Background

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

BACKGROUND_COLOR

BACKGROUND_RADIUS

BACKGROUND_INSETS

BACKGROUND_IMAGE

BACKGROUND_REPEAT

BACKGROUND_POSITION

BACKGROUND_SIZE

STYLEABLES

EMPTY

fills

images

outsets

hasOpaqueFill

opaqueFillTop

opaqueFillRight

opaqueFillBottom

opaqueFillLeft

hasPercentageBasedOpaqueFills

hasPercentageBasedFills

hash

Constructor Detail

Background

Background

Background

Background

Method Detail

getClassCssMetaData

getFills

getImages

getOutsets

isEmpty

isFillPercentageBased

computeOpaqueInsets

computeOpaqueInsets

equals

hashCode