Added in API level 1

ScaleDrawable

open class ScaleDrawable : DrawableWrapper
kotlin.Any
   ↳ android.graphics.drawable.Drawable
   ↳ android.graphics.drawable.DrawableWrapper
   ↳ android.graphics.drawable.ScaleDrawable

A Drawable that changes the size of another Drawable based on its current level value. You can control how much the child Drawable changes in width and height based on the level, as well as a gravity to control where it is placed in its overall container. Most often used to implement things like progress bars.

The default level may be specified from XML using the android:level property. When this property is not specified, the default level is 0, which corresponds to zero height and/or width depending on the values specified for android.R.styleable#ScaleDrawable_scaleWidth scaleWidth and android.R.styleable#ScaleDrawable_scaleHeight scaleHeight. At run time, the level may be set via setLevel(int).

A scale drawable may be defined in an XML file with the <scale> element. For more information, see the guide to Drawable Resources.

Summary

XML attributes
android:drawable Reference to a drawable resource to draw with the specified scale.
android:level Specifies the initial drawable level in the range 0 to 10000.
android:scaleGravity Specifies where the drawable is positioned after scaling.
android:scaleHeight Scale height, expressed as a percentage of the drawable's bound.
android:scaleWidth Scale width, expressed as a percentage of the drawable's bound.
Public constructors
ScaleDrawable(drawable: Drawable!, gravity: Int, scaleWidth: Float, scaleHeight: Float)

Creates a new scale drawable with the specified gravity and scale properties.

Public methods
open Unit

Applies the specified theme to this Drawable and its children.

open Unit
draw(canvas: Canvas)

open Int

open Unit
inflate(r: Resources, parser: XmlPullParser, attrs: AttributeSet, theme: Resources.Theme?)

Inflate this Drawable from an XML resource optionally styled by a theme.

Protected methods
open Unit

open Boolean

Inherited functions

XML attributes

android:drawable

android:drawable
Reference to a drawable resource to draw with the specified scale.

May be a reference to another resource, in the form "@[+][package:]type/name" or a theme attribute in the form "?[package:]type/name".

android:level

android:level
Specifies the initial drawable level in the range 0 to 10000.

May be an integer value, such as "100".

android:scaleGravity

android:scaleGravity
Specifies where the drawable is positioned after scaling. The default value is left.

Must be one or more (separated by '|') of the following constant values.

Constant Value Description
bottom 50 Push object to the bottom of its container, not changing its size.
center 11 Place the object in the center of its container in both the vertical and horizontal axis, not changing its size.
center_horizontal 1 Place object in the horizontal center of its container, not changing its size.
center_vertical 10 Place object in the vertical center of its container, not changing its size.
clip_horizontal 8 Additional option that can be set to have the left and/or right edges of the child clipped to its container's bounds. The clip will be based on the horizontal gravity: a left gravity will clip the right edge, a right gravity will clip the left edge, and neither will clip both edges.
clip_vertical 80 Additional option that can be set to have the top and/or bottom edges of the child clipped to its container's bounds. The clip will be based on the vertical gravity: a top gravity will clip the bottom edge, a bottom gravity will clip the top edge, and neither will clip both edges.
end 800005 Push object to the end of its container, not changing its size.
fill 77 Grow the horizontal and vertical size of the object if needed so it completely fills its container.
fill_horizontal 7 Grow the horizontal size of the object if needed so it completely fills its container.
fill_vertical 70 Grow the vertical size of the object if needed so it completely fills its container.
left 3 Push object to the left of its container, not changing its size.
right 5 Push object to the right of its container, not changing its size.
start 800003 Push object to the beginning of its container, not changing its size.
top 30 Push object to the top of its container, not changing its size.

android:scaleHeight

android:scaleHeight
Scale height, expressed as a percentage of the drawable's bound. The value's format is XX%. For instance: 100%, 12.5%, etc.

May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;

android:scaleWidth

android:scaleWidth
Scale width, expressed as a percentage of the drawable's bound. The value's format is XX%. For instance: 100%, 12.5%, etc.

May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;

Public constructors

ScaleDrawable

Added in API level 1
ScaleDrawable(
    drawable: Drawable!,
    gravity: Int,
    scaleWidth: Float,
    scaleHeight: Float)

Creates a new scale drawable with the specified gravity and scale properties.

Parameters
drawable Drawable!: the drawable to scale
gravity Int: gravity constant (see Gravity used to position the scaled drawable within the parent container
scaleWidth Float: width scaling factor [0...1] to use then the level is at the maximum value, or -1 to not scale width
scaleHeight Float: height scaling factor [0...1] to use then the level is at the maximum value, or -1 to not scale height

Public methods

applyTheme

Added in API level 21
open fun applyTheme(t: Resources.Theme): Unit

Applies the specified theme to this Drawable and its children.

Parameters
t Resources.Theme: This value cannot be null.

draw

Added in API level 1
open fun draw(canvas: Canvas): Unit
Parameters
canvas Canvas: This value cannot be null.

getOpacity

Added in API level 1
open fun getOpacity(): Int
Return
Int int The opacity class of the Drawable. Value is android.graphics.PixelFormat#UNKNOWN, android.graphics.PixelFormat#TRANSLUCENT, android.graphics.PixelFormat#TRANSPARENT, or android.graphics.PixelFormat#OPAQUE

inflate

Added in API level 21
open fun inflate(
    r: Resources,
    parser: XmlPullParser,
    attrs: AttributeSet,
    theme: Resources.Theme?
): Unit

Inflate this Drawable from an XML resource optionally styled by a theme. This can't be called more than once for each Drawable. Note that framework may have called this once to create the Drawable instance from XML resource.

Parameters
r Resources: This value cannot be null.
parser XmlPullParser: This value cannot be null.
attrs AttributeSet: This value cannot be null.
theme Resources.Theme?: This value may be null.
Exceptions
org.xmlpull.v1.XmlPullParserException
java.io.IOException

Protected methods

onBoundsChange

Added in API level 1
protected open fun onBoundsChange(bounds: Rect): Unit
Parameters
bounds Rect: This value cannot be null.

onLevelChange

Added in API level 1
protected open fun onLevelChange(level: Int): Boolean
Return
Boolean Returns true if the level change has caused the appearance of the Drawable to change (that is, it needs to be drawn), else false if it looks the same and there is no need to redraw it since its last level.