public class

GradientDrawable

extends Drawable
java.lang.Object
   ↳android.graphics.drawable.Drawable
    ↳android.graphics.drawable.GradientDrawable

Class Overview

A Drawable with a color gradient for buttons, backgrounds, etc.

It can be defined in an XML file with the <shape> element. For more information, see the guide to Drawable Resources.

Summary

Nested Classes
enumGradientDrawable.OrientationControls how the gradient is oriented relative to the drawable's bounds  
XML Attributes
Attribute NameRelated MethodDescription
android:angle  
android:bottom  
android:centerColor Optional center color. 
android:centerX  
android:centerY  
android:color  
android:color  
android:dashGap  
android:dashWidth  
android:endColor  
android:gradientRadius  
android:height Makes the TextView be exactly this many pixels tall. 
android:innerRadius Inner radius of the ring. 
android:innerRadiusRatio Inner radius of the ring expressed as a ratio of the ring's width. 
android:left  
android:right  
android:shape  
android:startColor  
android:thickness Thickness of the ring. 
android:thicknessRatio Thickness of the ring expressed as a ratio of the ring's width. 
android:top  
android:type  
android:useLevel  
android:useLevel  
android:visible Provides initial visibility state of the drawable; the default value is false. 
android:width Makes the TextView be exactly this many pixels wide. 
android:width Makes the TextView be exactly this many pixels wide. 
Constants
intLINEShape is a line
intLINEAR_GRADIENTGradient is linear (default.)
intOVALShape is an ellipse
intRADIAL_GRADIENTGradient is circular.
intRECTANGLEShape is a rectangle, possibly with rounded corners
intRINGShape is a ring.
intSWEEP_GRADIENTGradient is a sweep.
Public Constructors
GradientDrawable()
GradientDrawable(GradientDrawable.Orientation orientation, int[] colors)
Create a new gradient drawable given an orientation and an array of colors for the gradient.
Public Methods
void draw(Canvas canvas)
Draw in its bounds (set via setBounds) respecting optional effects such as alpha (set via setAlpha) and color filter (set via setColorFilter).
int getChangingConfigurations()
Return a mask of the configuration parameters for which this drawable mau change, requiring that it be re-created.
Drawable.ConstantState getConstantState()
int getIntrinsicHeight()
Return the intrinsic height of the underlying drawable object.
int getIntrinsicWidth()
Return the intrinsic width of the underlying drawable object.
int getOpacity()
Return the opacity/transparency of this Drawable.
boolean getPadding(Rect padding)
Return in padding the insets suggested by this Drawable for placing content inside the drawable's bounds.
void inflate(Resources r, XmlPullParser parser, AttributeSet attrs)
Drawable mutate()
Make this drawable mutable.
void setAlpha(int alpha)
Specify an alpha value for the drawable.
void setColor(int argb)
void setColorFilter(ColorFilter cf)
Specify an optional colorFilter for the drawable.
void setCornerRadii(float[] radii)
Specify radii for each of the 4 corners.
void setCornerRadius(float radius)
Specify radius for the corners of the gradient.
void setDither(boolean dither)
Set to true to have the drawable dither its colors when drawn to a device with fewer than 8-bits per color component.
void setGradientCenter(float x, float y)
void setGradientRadius(float gradientRadius)
void setGradientType(int gradient)
void setShape(int shape)
void setSize(int width, int height)
void setStroke(int width, int color, float dashWidth, float dashGap)
void setStroke(int width, int color)
Set the stroke width and color for the drawable.
void setUseLevel(boolean useLevel)
Protected Methods
void onBoundsChange(Rect r)
Override this in your subclass to change appearance if you recognize the specified state.
boolean onLevelChange(int level)
Override this in your subclass to change appearance if you vary based on level.
[Expand]
Inherited Methods
From class android.graphics.drawable.Drawable
From class java.lang.Object

XML Attributes

android:angle

Since: API Level

Related Methods

    android:bottom

    Since: API Level

    Related Methods

      android:centerColor

      Since: API Level

      Optional center color. For linear gradients, use centerX or centerY to place the center color.

      Must be a color value, in the form of "#rgb", "#argb", "#rrggbb", or "#aarrggbb".

      This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

      This corresponds to the global attribute resource symbol centerColor.

      Related Methods

        android:centerX

        Since: API Level

        Related Methods

          android:centerY

          Since: API Level

          Related Methods

            android:color

            Since: API Level

            Related Methods

              android:color

              Since: API Level

              Related Methods

                android:dashGap

                Since: API Level

                Related Methods

                  android:dashWidth

                  Since: API Level

                  Related Methods

                    android:endColor

                    Since: API Level

                    Related Methods

                      android:gradientRadius

                      Since: API Level

                      Related Methods

                        android:height

                        Since: API Level

                        Makes the TextView be exactly this many pixels tall. You could get the same effect by specifying this number in the layout parameters.

                        Must be a dimension value, which is a floating point number appended with a unit such as "14.5sp". Available units are: px (pixels), dp (density-independent pixels), sp (scaled pixels based on preferred font size), in (inches), mm (millimeters).

                        This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                        This corresponds to the global attribute resource symbol height.

                        Related Methods

                          android:innerRadius

                          Since: API Level

                          Inner radius of the ring. When defined, innerRadiusRatio is ignored.

                          Must be a dimension value, which is a floating point number appended with a unit such as "14.5sp". Available units are: px (pixels), dp (density-independent pixels), sp (scaled pixels based on preferred font size), in (inches), mm (millimeters).

                          This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                          This corresponds to the global attribute resource symbol innerRadius.

                          Related Methods

                            android:innerRadiusRatio

                            Since: API Level

                            Inner radius of the ring expressed as a ratio of the ring's width. For instance, if innerRadiusRatio=9, then the inner radius equals the ring's width divided by 9. This value is ignored if innerRadius is defined. Default value is 9.

                            Must be a floating point value, such as "1.2".

                            This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                            This corresponds to the global attribute resource symbol innerRadiusRatio.

                            Related Methods

                              android:left

                              Since: API Level

                              Related Methods

                                android:right

                                Since: API Level

                                Related Methods

                                  android:shape

                                  Since: API Level

                                  Related Methods

                                    android:startColor

                                    Since: API Level

                                    Related Methods

                                      android:thickness

                                      Since: API Level

                                      Thickness of the ring. When defined, thicknessRatio is ignored.

                                      Must be a dimension value, which is a floating point number appended with a unit such as "14.5sp". Available units are: px (pixels), dp (density-independent pixels), sp (scaled pixels based on preferred font size), in (inches), mm (millimeters).

                                      This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                                      This corresponds to the global attribute resource symbol thickness.

                                      Related Methods

                                        android:thicknessRatio

                                        Since: API Level

                                        Thickness of the ring expressed as a ratio of the ring's width. For instance, if thicknessRatio=3, then the thickness equals the ring's width divided by 3. This value is ignored if innerRadius is defined. Default value is 3.

                                        Must be a floating point value, such as "1.2".

                                        This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                                        This corresponds to the global attribute resource symbol thicknessRatio.

                                        Related Methods

                                          android:top

                                          Since: API Level

                                          Related Methods

                                            android:type

                                            Since: API Level

                                            Related Methods

                                              android:useLevel

                                              Since: API Level

                                              Related Methods

                                                android:useLevel

                                                Since: API Level

                                                Related Methods

                                                  android:visible

                                                  Since: API Level

                                                  Provides initial visibility state of the drawable; the default value is false. See setVisible(boolean, boolean).

                                                  Must be a boolean value, either "true" or "false".

                                                  This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                                                  This corresponds to the global attribute resource symbol visible.

                                                  Related Methods

                                                    android:width

                                                    Since: API Level

                                                    Makes the TextView be exactly this many pixels wide. You could get the same effect by specifying this number in the layout parameters.

                                                    Must be a dimension value, which is a floating point number appended with a unit such as "14.5sp". Available units are: px (pixels), dp (density-independent pixels), sp (scaled pixels based on preferred font size), in (inches), mm (millimeters).

                                                    This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                                                    This corresponds to the global attribute resource symbol width.

                                                    Related Methods

                                                      android:width

                                                      Since: API Level

                                                      Makes the TextView be exactly this many pixels wide. You could get the same effect by specifying this number in the layout parameters.

                                                      Must be a dimension value, which is a floating point number appended with a unit such as "14.5sp". Available units are: px (pixels), dp (density-independent pixels), sp (scaled pixels based on preferred font size), in (inches), mm (millimeters).

                                                      This may also be a reference to a resource (in the form "@[package:]type:name") or theme attribute (in the form "?[package:][type:]name") containing a value of this type.

                                                      This corresponds to the global attribute resource symbol width.

                                                      Related Methods

                                                        Constants

                                                        public static final int LINE

                                                        Since: API Level 1

                                                        Shape is a line

                                                        Constant Value: 2 (0x00000002)

                                                        public static final int LINEAR_GRADIENT

                                                        Since: API Level 1

                                                        Gradient is linear (default.)

                                                        Constant Value: 0 (0x00000000)

                                                        public static final int OVAL

                                                        Since: API Level 1

                                                        Shape is an ellipse

                                                        Constant Value: 1 (0x00000001)

                                                        public static final int RADIAL_GRADIENT

                                                        Since: API Level 1

                                                        Gradient is circular.

                                                        Constant Value: 1 (0x00000001)

                                                        public static final int RECTANGLE

                                                        Since: API Level 1

                                                        Shape is a rectangle, possibly with rounded corners

                                                        Constant Value: 0 (0x00000000)

                                                        public static final int RING

                                                        Since: API Level 1

                                                        Shape is a ring.

                                                        Constant Value: 3 (0x00000003)

                                                        public static final int SWEEP_GRADIENT

                                                        Since: API Level 1

                                                        Gradient is a sweep.

                                                        Constant Value: 2 (0x00000002)

                                                        Public Constructors

                                                        public GradientDrawable ()

                                                        Since: API Level 1

                                                        public GradientDrawable (GradientDrawable.Orientation orientation, int[] colors)

                                                        Since: API Level 1

                                                        Create a new gradient drawable given an orientation and an array of colors for the gradient.

                                                        Public Methods

                                                        public void draw (Canvas canvas)

                                                        Since: API Level 1

                                                        Draw in its bounds (set via setBounds) respecting optional effects such as alpha (set via setAlpha) and color filter (set via setColorFilter).

                                                        Parameters
                                                        canvas The canvas to draw into

                                                        public int getChangingConfigurations ()

                                                        Since: API Level 1

                                                        Return a mask of the configuration parameters for which this drawable mau change, requiring that it be re-created. The default implementation returns whatever was provided through setChangingConfigurations(int) or 0 by default. Subclasses may extend this to or in the changing configurations of any other drawables they hold.

                                                        Returns
                                                        • Returns a mask of the changing configuration parameters, as defined by Configuration.

                                                        public Drawable.ConstantState getConstantState ()

                                                        Since: API Level 1

                                                        public int getIntrinsicHeight ()

                                                        Since: API Level 1

                                                        Return the intrinsic height of the underlying drawable object. Returns -1 if it has no intrinsic height, such as with a solid color.

                                                        public int getIntrinsicWidth ()

                                                        Since: API Level 1

                                                        Return the intrinsic width of the underlying drawable object. Returns -1 if it has no intrinsic width, such as with a solid color.

                                                        public int getOpacity ()

                                                        Since: API Level 1

                                                        Return the opacity/transparency of this Drawable. The returned value is one of the abstract format constants in PixelFormat: UNKNOWN, TRANSLUCENT, TRANSPARENT, or OPAQUE.

                                                        Generally a Drawable should be as conservative as possible with the value it returns. For example, if it contains multiple child drawables and only shows one of them at a time, if only one of the children is TRANSLUCENT and the others are OPAQUE then TRANSLUCENT should be returned. You can use the method resolveOpacity(int, int) to perform a standard reduction of two opacities to the appropriate single output.

                                                        Note that the returned value does not take into account a custom alpha or color filter that has been applied by the client through the setAlpha(int) or setColorFilter(ColorFilter) methods.

                                                        Returns
                                                        • int The opacity class of the Drawable.

                                                        public boolean getPadding (Rect padding)

                                                        Since: API Level 1

                                                        Return in padding the insets suggested by this Drawable for placing content inside the drawable's bounds. Positive values move toward the center of the Drawable (set Rect.inset). Returns true if this drawable actually has a padding, else false. When false is returned, the padding is always set to 0.

                                                        public void inflate (Resources r, XmlPullParser parser, AttributeSet attrs)

                                                        Since: API Level 1

                                                        public Drawable mutate ()

                                                        Since: API Level 3

                                                        Make this drawable mutable. This operation cannot be reversed. A mutable drawable is guaranteed to not share its state with any other drawable. This is especially useful when you need to modify properties of drawables loaded from resources. By default, all drawables instances loaded from the same resource share a common state; if you modify the state of one instance, all the other instances will receive the same modification. Calling this method on a mutable Drawable will have no effect.

                                                        Returns
                                                        • This drawable.

                                                        public void setAlpha (int alpha)

                                                        Since: API Level 1

                                                        Specify an alpha value for the drawable. 0 means fully transparent, and 255 means fully opaque.

                                                        public void setColor (int argb)

                                                        Since: API Level 1

                                                        public void setColorFilter (ColorFilter cf)

                                                        Since: API Level 1

                                                        Specify an optional colorFilter for the drawable. Pass null to remove any filters.

                                                        public void setCornerRadii (float[] radii)

                                                        Since: API Level 1

                                                        Specify radii for each of the 4 corners. For each corner, the array contains 2 values, [X_radius, Y_radius]. The corners are ordered top-left, top-right, bottom-right, bottom-left

                                                        public void setCornerRadius (float radius)

                                                        Since: API Level 1

                                                        Specify radius for the corners of the gradient. If this is > 0, then the drawable is drawn in a round-rectangle, rather than a rectangle.

                                                        public void setDither (boolean dither)

                                                        Since: API Level 1

                                                        Set to true to have the drawable dither its colors when drawn to a device with fewer than 8-bits per color component. This can improve the look on those devices, but can also slow down the drawing a little.

                                                        public void setGradientCenter (float x, float y)

                                                        Since: API Level 1

                                                        public void setGradientRadius (float gradientRadius)

                                                        Since: API Level 1

                                                        public void setGradientType (int gradient)

                                                        Since: API Level 1

                                                        public void setShape (int shape)

                                                        Since: API Level 1

                                                        public void setSize (int width, int height)

                                                        Since: API Level 1

                                                        public void setStroke (int width, int color, float dashWidth, float dashGap)

                                                        Since: API Level 1

                                                        public void setStroke (int width, int color)

                                                        Since: API Level 1

                                                        Set the stroke width and color for the drawable. If width is zero, then no stroke is drawn.

                                                        public void setUseLevel (boolean useLevel)

                                                        Since: API Level 1

                                                        Protected Methods

                                                        protected void onBoundsChange (Rect r)

                                                        Since: API Level 1

                                                        Override this in your subclass to change appearance if you recognize the specified state.

                                                        protected boolean onLevelChange (int level)

                                                        Since: API Level 1

                                                        Override this in your subclass to change appearance if you vary based on level.

                                                        Returns
                                                        • 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.