public
abstract
class
Shape
extends Object
implements
Cloneable
java.lang.Object | |
↳ | android.graphics.drawable.shapes.Shape |
Known Direct Subclasses |
Known Indirect Subclasses |
Defines a generic graphical "shape."
Any Shape can be drawn to a Canvas with its own draw() method,
but more graphical control is available if you instead pass
it to a ShapeDrawable
.
Public constructors | |
---|---|
Shape()
|
Public methods | |
---|---|
Shape
|
clone()
Creates and returns a copy of this object. |
abstract
void
|
draw(Canvas canvas, Paint paint)
Draw this shape into the provided Canvas, with the provided Paint. |
final
float
|
getHeight()
Returns the height of the Shape. |
void
|
getOutline(Outline outline)
Compute the Outline of the shape and return it in the supplied Outline parameter. |
final
float
|
getWidth()
Returns the width of the Shape. |
boolean
|
hasAlpha()
Checks whether the Shape is opaque. |
final
void
|
resize(float width, float height)
Resizes the dimensions of this shape. |
Protected methods | |
---|---|
void
|
onResize(float width, float height)
Callback method called when |
Inherited methods | |
---|---|
From
class
java.lang.Object
|
Shape clone ()
Creates and returns a copy of this object. The precise meaning
of "copy" may depend on the class of the object. The general
intent is that, for any object x
, the expression:
will be true, and that the expression:x.clone() != x
will bex.clone().getClass() == x.getClass()
true
, but these are not absolute requirements.
While it is typically the case that:
will bex.clone().equals(x)
true
, this is not an absolute requirement.
By convention, the returned object should be obtained by calling
super.clone
. If a class and all of its superclasses (except
Object
) obey this convention, it will be the case that
x.clone().getClass() == x.getClass()
.
By convention, the object returned by this method should be independent
of this object (which is being cloned). To achieve this independence,
it may be necessary to modify one or more fields of the object returned
by super.clone
before returning it. Typically, this means
copying any mutable objects that comprise the internal "deep structure"
of the object being cloned and replacing the references to these
objects with references to the copies. If a class contains only
primitive fields or references to immutable objects, then it is usually
the case that no fields in the object returned by super.clone
need to be modified.
The method clone
for class Object
performs a
specific cloning operation. First, if the class of this object does
not implement the interface Cloneable
, then a
CloneNotSupportedException
is thrown. Note that all arrays
are considered to implement the interface Cloneable
and that
the return type of the clone
method of an array type T[]
is T[]
where T is any reference or primitive type.
Otherwise, this method creates a new instance of the class of this
object and initializes all its fields with exactly the contents of
the corresponding fields of this object, as if by assignment; the
contents of the fields are not themselves cloned. Thus, this method
performs a "shallow copy" of this object, not a "deep copy" operation.
The class Object
does not itself implement the interface
Cloneable
, so calling the clone
method on an object
whose class is Object
will result in throwing an
exception at run time.
Returns | |
---|---|
Shape |
a clone of this instance. |
Throws | |
---|---|
CloneNotSupportedException |
void draw (Canvas canvas, Paint paint)
Draw this shape into the provided Canvas, with the provided Paint.
Before calling this, you must call resize(float, float)
.
Parameters | |
---|---|
canvas |
Canvas :
the Canvas within which this shape should be drawn |
paint |
Paint :
the Paint object that defines this shape's characteristics
|
void getOutline (Outline outline)
Compute the Outline of the shape and return it in the supplied Outline
parameter. The default implementation does nothing and outline
is not changed.
Parameters | |
---|---|
outline |
Outline :
The Outline to be populated with the result. Should not be null.
|
boolean hasAlpha ()
Checks whether the Shape is opaque. Default impl returns true. Override if your subclass can be opaque.
Returns | |
---|---|
boolean |
true if any part of the drawable is not opaque. |
void resize (float width, float height)
Resizes the dimensions of this shape.
Must be called before draw(Canvas, Paint)
.
Parameters | |
---|---|
width |
float :
the width of the shape (in pixels) |
height |
float :
the height of the shape (in pixels)
|
void onResize (float width, float height)
Callback method called when resize(float, float)
is executed.
Parameters | |
---|---|
width |
float :
the new width of the Shape |
height |
float :
the new height of the Shape
|