NinePatchDrawable
public
class
NinePatchDrawable
extends Drawable
java.lang.Object | ||
↳ | android.graphics.drawable.Drawable | |
↳ | android.graphics.drawable.NinePatchDrawable |
A resizeable bitmap, with stretchable areas that you define. This type of image is defined in a .png file with a special format.
Developer Guides
For more information about how to use a NinePatchDrawable, read the Canvas and Drawables developer guide. For information about creating a NinePatch image file using the draw9patch tool, see the Draw 9-patch tool guide.
Summary
Public constructors | |
---|---|
NinePatchDrawable(Resources res, Bitmap bitmap, byte[] chunk, Rect padding, String srcName)
Create drawable from raw nine-patch data, setting initial target density based on the display metrics of the resources. |
|
NinePatchDrawable(Resources res, NinePatch patch)
Create drawable from existing nine-patch, setting initial target density based on the display metrics of the resources. |
|
NinePatchDrawable(Bitmap bitmap, byte[] chunk, Rect padding, String srcName)
This constructor is deprecated.
Use |
|
NinePatchDrawable(NinePatch patch)
This constructor is deprecated.
Use |
Public methods | |
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void
|
applyTheme(Resources.Theme t)
Applies the specified theme to this Drawable and its children. |
boolean
|
canApplyTheme()
|
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
|
getAlpha()
Gets the current alpha value for the drawable. |
int
|
getChangingConfigurations()
Return a mask of the configuration parameters for which this drawable may change, requiring that it be re-created. |
Drawable.ConstantState
|
getConstantState()
Return a |
int
|
getIntrinsicHeight()
Returns the drawable's intrinsic height. |
int
|
getIntrinsicWidth()
Returns the drawable's intrinsic width. |
int
|
getOpacity()
This method is deprecated. This method is no longer used in graphics optimizations |
Insets
|
getOpticalInsets()
Return in insets the layout insets suggested by this Drawable for use with alignment operations during layout. |
void
|
getOutline(Outline outline)
Called to get the drawable to populate the Outline that defines its drawing area. |
boolean
|
getPadding(Rect padding)
Return in padding the insets suggested by this Drawable for placing content inside the drawable's bounds. |
Paint
|
getPaint()
|
Region
|
getTransparentRegion()
Returns a Region representing the part of the Drawable that is completely transparent. |
boolean
|
hasFocusStateSpecified()
Indicates whether this drawable has at least one state spec explicitly
specifying |
void
|
inflate(Resources r, XmlPullParser parser, AttributeSet attrs, Resources.Theme theme)
Inflate this Drawable from an XML resource optionally styled by a theme. |
boolean
|
isAutoMirrored()
Tells if this Drawable will be automatically mirrored when its layout direction is RTL right-to-left. |
boolean
|
isFilterBitmap()
|
boolean
|
isStateful()
Indicates whether this drawable will change its appearance based on state. |
Drawable
|
mutate()
Make this drawable mutable. |
void
|
setAlpha(int alpha)
Specify an alpha value for the drawable. |
void
|
setAutoMirrored(boolean mirrored)
Set whether this Drawable is automatically mirrored when its layout direction is RTL (right-to left). |
void
|
setColorFilter(ColorFilter colorFilter)
Specify an optional color filter for the drawable. |
void
|
setDither(boolean dither)
This method is deprecated. This property is ignored. |
void
|
setFilterBitmap(boolean filter)
Set to true to have the drawable filter its bitmaps with bilinear sampling when they are scaled or rotated. |
void
|
setTargetDensity(DisplayMetrics metrics)
Set the density scale at which this drawable will be rendered. |
void
|
setTargetDensity(Canvas canvas)
Set the density scale at which this drawable will be rendered. |
void
|
setTargetDensity(int density)
Set the density at which this drawable will be rendered. |
void
|
setTintBlendMode(BlendMode blendMode)
Specifies a tint blending mode for this drawable. |
void
|
setTintList(ColorStateList tint)
Specifies tint color for this drawable as a color state list. |
Protected methods | |
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boolean
|
onStateChange(int[] stateSet)
Override this in your subclass to change appearance if you recognize the specified state. |
Inherited methods | |
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Public constructors
NinePatchDrawable
public NinePatchDrawable (Resources res, Bitmap bitmap, byte[] chunk, Rect padding, String srcName)
Create drawable from raw nine-patch data, setting initial target density based on the display metrics of the resources.
Parameters | |
---|---|
res |
Resources |
bitmap |
Bitmap |
chunk |
byte |
padding |
Rect |
srcName |
String |
NinePatchDrawable
public NinePatchDrawable (Resources res, NinePatch patch)
Create drawable from existing nine-patch, setting initial target density based on the display metrics of the resources.
Parameters | |
---|---|
res |
Resources : This value may be null . |
patch |
NinePatch : This value cannot be null . |
NinePatchDrawable
public NinePatchDrawable (Bitmap bitmap, byte[] chunk, Rect padding, String srcName)
This constructor is deprecated.
Use NinePatchDrawable(android.content.res.Resources, android.graphics.Bitmap, byte[], android.graphics.Rect, java.lang.String)
to ensure that the drawable has correctly set its target density.
Create drawable from raw nine-patch data, not dealing with density.
Parameters | |
---|---|
bitmap |
Bitmap |
chunk |
byte |
padding |
Rect |
srcName |
String |
NinePatchDrawable
public NinePatchDrawable (NinePatch patch)
This constructor is deprecated.
Use NinePatchDrawable(android.content.res.Resources, android.graphics.NinePatch)
to ensure that the drawable has correctly set its target
density.
Create drawable from existing nine-patch, not dealing with density.
Parameters | |
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patch |
NinePatch : This value cannot be null . |
Public methods
applyTheme
public void applyTheme (Resources.Theme t)
Applies the specified theme to this Drawable and its children.
Parameters | |
---|---|
t |
Resources.Theme : This value cannot be null . |
draw
public 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).
Parameters | |
---|---|
canvas |
Canvas : The canvas to draw into
This value cannot be null . |
getAlpha
public int getAlpha ()
Gets the current alpha value for the drawable. 0 means fully transparent, 255 means fully opaque. This method is implemented by Drawable subclasses and the value returned is specific to how that class treats alpha. The default return value is 255 if the class does not override this method to return a value specific to its use of alpha.
Returns | |
---|---|
int |
Value is between 0 and 255 inclusive |
getChangingConfigurations
public int getChangingConfigurations ()
Return a mask of the configuration parameters for which this drawable
may 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.
getConstantState
public Drawable.ConstantState getConstantState ()
Return a ConstantState
instance that holds the shared state of this Drawable.
Returns | |
---|---|
Drawable.ConstantState |
The ConstantState associated to that Drawable.
This value may be null . |
getIntrinsicHeight
public int getIntrinsicHeight ()
Returns the drawable's intrinsic height.
Intrinsic height is the height at which the drawable would like to be laid out, including any inherent padding. If the drawable has no intrinsic height, such as a solid color, this method returns -1.
Returns | |
---|---|
int |
the intrinsic height, or -1 if no intrinsic height |
getIntrinsicWidth
public int getIntrinsicWidth ()
Returns the drawable's intrinsic width.
Intrinsic width is the width at which the drawable would like to be laid out, including any inherent padding. If the drawable has no intrinsic width, such as a solid color, this method returns -1.
Returns | |
---|---|
int |
the intrinsic width, or -1 if no intrinsic width |
getOpacity
public int getOpacity ()
This method is deprecated.
This method is no longer used in graphics optimizations
Return the opacity/transparency of this Drawable. The returned value is
one of the abstract format constants in
PixelFormat
:
PixelFormat.UNKNOWN
,
PixelFormat.TRANSLUCENT
,
PixelFormat.TRANSPARENT
, or
PixelFormat.OPAQUE
.
An OPAQUE drawable is one that draws all all content within its bounds, completely covering anything behind the drawable. A TRANSPARENT drawable is one that draws nothing within its bounds, allowing everything behind it to show through. A TRANSLUCENT drawable is a drawable in any other state, where the drawable will draw some, but not all, of the content within its bounds and at least some content behind the drawable will be visible. If the visibility of the drawable's contents cannot be determined, the safest/best return value is TRANSLUCENT.
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 necessarily take into account a
custom alpha or color filter that has been applied by the client through
the setAlpha(int)
or setColorFilter(ColorFilter)
methods. Some subclasses,
such as BitmapDrawable
, ColorDrawable
, and GradientDrawable
,
do account for the value of setAlpha(int)
, but the general behavior is dependent
upon the implementation of the subclass.
Returns | |
---|---|
int |
int The opacity class of the Drawable.
Value is PixelFormat.UNKNOWN , PixelFormat.TRANSLUCENT , PixelFormat.TRANSPARENT , or PixelFormat.OPAQUE |
getOpticalInsets
public Insets getOpticalInsets ()
Return in insets the layout insets suggested by this Drawable for use with alignment operations during layout.
Returns | |
---|---|
Insets |
This value cannot be null . |
getOutline
public void getOutline (Outline outline)
Called to get the drawable to populate the Outline that defines its drawing area.
This method is called by the default ViewOutlineProvider
to define
the outline of the View.
The default behavior defines the outline to be the bounding rectangle of 0 alpha. Subclasses that wish to convey a different shape or alpha value must override this method.
Parameters | |
---|---|
outline |
Outline : This value cannot be null . |
getPadding
public boolean getPadding (Rect padding)
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).
Parameters | |
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padding |
Rect : This value cannot be null . |
Returns | |
---|---|
boolean |
true if this drawable actually has a padding, else false. When false is returned, the padding is always set to 0. |
getTransparentRegion
public Region getTransparentRegion ()
Returns a Region representing the part of the Drawable that is completely transparent. This can be used to perform drawing operations, identifying which parts of the target will not change when rendering the Drawable. The default implementation returns null, indicating no transparent region; subclasses can optionally override this to return an actual Region if they want to supply this optimization information, but it is not required that they do so.
Returns | |
---|---|
Region |
Returns null if the Drawables has no transparent region to report, else a Region holding the parts of the Drawable's bounds that are transparent. |
hasFocusStateSpecified
public boolean hasFocusStateSpecified ()
Indicates whether this drawable has at least one state spec explicitly
specifying R.attr.state_focused
.
Note: A View uses a Drawable
instance as its background and it
changes its appearance based on a state. On keyboard devices, it should
specify its R.attr.state_focused
to make sure the user
knows which view is holding the focus.
Returns | |
---|---|
boolean |
true if R.attr.state_focused is specified
for this drawable. |
inflate
public void inflate (Resources r, XmlPullParser parser, AttributeSet attrs, Resources.Theme theme)
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 : Resources used to resolve attribute values
This value cannot be null . |
parser |
XmlPullParser : XML parser from which to inflate this Drawable
This value cannot be null . |
attrs |
AttributeSet : Base set of attribute values
This value cannot be null . |
theme |
Resources.Theme : Theme to apply, may be null |
Throws | |
---|---|
IOException |
|
XmlPullParserException |
isAutoMirrored
public boolean isAutoMirrored ()
Tells if this Drawable will be automatically mirrored when its layout direction is RTL
right-to-left. See LayoutDirection
.
Returns | |
---|---|
boolean |
boolean Returns true if this Drawable will be automatically mirrored. |
isFilterBitmap
public boolean isFilterBitmap ()
Returns | |
---|---|
boolean |
whether this drawable filters its bitmaps |
isStateful
public boolean isStateful ()
Indicates whether this drawable will change its appearance based on state. Clients can use this to determine whether it is necessary to calculate their state and call setState.
Returns | |
---|---|
boolean |
True if this drawable changes its appearance based on state, false otherwise. |
mutate
public Drawable mutate ()
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 | |
---|---|
Drawable |
This drawable.
This value cannot be null . |
setAlpha
public void setAlpha (int alpha)
Specify an alpha value for the drawable. 0 means fully transparent, and 255 means fully opaque.
Parameters | |
---|---|
alpha |
int : Value is between 0 and 255 inclusive |
setAutoMirrored
public void setAutoMirrored (boolean mirrored)
Set whether this Drawable is automatically mirrored when its layout direction is RTL
(right-to left). See LayoutDirection
.
Parameters | |
---|---|
mirrored |
boolean : Set to true if the Drawable should be mirrored, false if not. |
setColorFilter
public void setColorFilter (ColorFilter colorFilter)
Specify an optional color filter for the drawable.
If a Drawable has a ColorFilter, each output pixel of the Drawable's drawing contents will be modified by the color filter before it is blended onto the render target of a Canvas.
Pass null
to remove any existing color filter.
Note: Setting a non-null
color
filter disables tint
.
Parameters | |
---|---|
colorFilter |
ColorFilter : This value may be null . |
setDither
public void setDither (boolean dither)
This method is deprecated.
This property is ignored.
Set to true to have the drawable dither its colors when drawn to a device with fewer than 8-bits per color component.
Parameters | |
---|---|
dither |
boolean |
setFilterBitmap
public void setFilterBitmap (boolean filter)
Set to true to have the drawable filter its bitmaps with bilinear sampling when they are scaled or rotated.
This can improve appearance when bitmaps are rotated. If the drawable does not use bitmaps, this call is ignored.
Parameters | |
---|---|
filter |
boolean |
setTargetDensity
public void setTargetDensity (DisplayMetrics metrics)
Set the density scale at which this drawable will be rendered.
Parameters | |
---|---|
metrics |
DisplayMetrics : The DisplayMetrics indicating the density scale for this drawable.
This value cannot be null . |
setTargetDensity
public void setTargetDensity (Canvas canvas)
Set the density scale at which this drawable will be rendered. This method assumes the drawable will be rendered at the same density as the specified canvas.
Parameters | |
---|---|
canvas |
Canvas : The Canvas from which the density scale must be obtained.
This value cannot be null . |
setTargetDensity
public void setTargetDensity (int density)
Set the density at which this drawable will be rendered.
Parameters | |
---|---|
density |
int : The density scale for this drawable. |
setTintBlendMode
public void setTintBlendMode (BlendMode blendMode)
Specifies a tint blending mode for this drawable.
Defines how this drawable's tint color should be blended into the drawable
before it is drawn to screen. Default tint mode is BlendMode.SRC_IN
.
Note: Setting a color filter via
setColorFilter(android.graphics.ColorFilter)
Parameters | |
---|---|
blendMode |
BlendMode : This value may be null . |
setTintList
public void setTintList (ColorStateList tint)
Specifies tint color for this drawable as a color state list.
A Drawable's drawing content will be blended together with its tint
before it is drawn to the screen. This functions similarly to
setColorFilter(int, android.graphics.PorterDuff.Mode)
.
Note: Setting a color filter via
setColorFilter(android.graphics.ColorFilter)
or
setColorFilter(int, android.graphics.PorterDuff.Mode)
overrides tint.
Parameters | |
---|---|
tint |
ColorStateList : This value may be null . |
Protected methods
onStateChange
protected boolean onStateChange (int[] stateSet)
Override this in your subclass to change appearance if you recognize the specified state.
Parameters | |
---|---|
stateSet |
int : This value cannot be null . |
Returns | |
---|---|
boolean |
Returns true if the state 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 state. |