Region
public
class
Region
extends Object
implements
Parcelable
java.lang.Object | |
↳ | android.graphics.Region |
Summary
Inherited constants |
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Fields | |
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public
static
final
Creator<Region> |
CREATOR
|
Public constructors | |
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Region()
Create an empty region |
|
Region(Rect r)
Return a region set to the specified rectangle |
|
Region(Region region)
Return a copy of the specified region |
|
Region(int left, int top, int right, int bottom)
Return a region set to the specified rectangle |
Public methods | |
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boolean
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contains(int x, int y)
Return true if the region contains the specified point |
int
|
describeContents()
Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. |
boolean
|
equals(Object obj)
Indicates whether some other object is "equal to" this one. |
boolean
|
getBoundaryPath(Path path)
Set the path to the boundary of the region. |
Path
|
getBoundaryPath()
Return the boundary of the region as a new Path. |
Rect
|
getBounds()
Return a new Rect set to the bounds of the region. |
boolean
|
getBounds(Rect r)
Set the Rect to the bounds of the region. |
boolean
|
isComplex()
Return true if the region contains more than one rectangle |
boolean
|
isEmpty()
Return true if this region is empty |
boolean
|
isRect()
Return true if the region contains a single rectangle |
boolean
|
op(Region region1, Region region2, Region.Op op)
Set this region to the result of performing the Op on the specified regions. |
boolean
|
op(Rect r, Region.Op op)
Perform the specified Op on this region and the specified rect. |
boolean
|
op(Rect rect, Region region, Region.Op op)
Set this region to the result of performing the Op on the specified rect and region. |
boolean
|
op(Region region, Region.Op op)
Perform the specified Op on this region and the specified region. |
boolean
|
op(int left, int top, int right, int bottom, Region.Op op)
Perform the specified Op on this region and the specified rect. |
boolean
|
quickContains(Rect r)
Return true if the region is a single rectangle (not complex) and it contains the specified rectangle. |
boolean
|
quickContains(int left, int top, int right, int bottom)
Return true if the region is a single rectangle (not complex) and it contains the specified rectangle. |
boolean
|
quickReject(Region rgn)
Return true if the region is empty, or if the specified region does not intersect the region. |
boolean
|
quickReject(Rect r)
Return true if the region is empty, or if the specified rectangle does not intersect the region. |
boolean
|
quickReject(int left, int top, int right, int bottom)
Return true if the region is empty, or if the specified rectangle does not intersect the region. |
boolean
|
set(int left, int top, int right, int bottom)
Set the region to the specified rectangle |
boolean
|
set(Region region)
Set the region to the specified region. |
boolean
|
set(Rect r)
Set the region to the specified rectangle |
void
|
setEmpty()
Set the region to the empty region |
boolean
|
setPath(Path path, Region clip)
Set the region to the area described by the path and clip. |
String
|
toString()
Returns a string representation of the object. |
void
|
translate(int dx, int dy, Region dst)
Set the dst region to the result of translating this region by [dx, dy]. |
void
|
translate(int dx, int dy)
Translate the region by [dx, dy]. |
final
boolean
|
union(Rect r)
|
void
|
writeToParcel(Parcel p, int flags)
Write the region and its pixels to the parcel. |
Protected methods | |
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void
|
finalize()
Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. |
Inherited methods | |
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Fields
Public constructors
Region
public Region (Rect r)
Return a region set to the specified rectangle
Parameters | |
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r |
Rect : This value cannot be null . |
Region
public Region (Region region)
Return a copy of the specified region
Parameters | |
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region |
Region : This value cannot be null . |
Region
public Region (int left, int top, int right, int bottom)
Return a region set to the specified rectangle
Parameters | |
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left |
int |
top |
int |
right |
int |
bottom |
int |
Public methods
contains
public boolean contains (int x, int y)
Return true if the region contains the specified point
Parameters | |
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x |
int |
y |
int |
Returns | |
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boolean |
describeContents
public int describeContents ()
Describe the kinds of special objects contained in this Parcelable
instance's marshaled representation. For example, if the object will
include a file descriptor in the output of writeToParcel(android.os.Parcel, int)
,
the return value of this method must include the
CONTENTS_FILE_DESCRIPTOR
bit.
Returns | |
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int |
a bitmask indicating the set of special object types marshaled
by this Parcelable object instance.
Value is either 0 or CONTENTS_FILE_DESCRIPTOR |
equals
public boolean equals (Object obj)
Indicates whether some other object is "equal to" this one.
The equals
method implements an equivalence relation
on non-null object references:
- It is reflexive: for any non-null reference value
x
,x.equals(x)
should returntrue
. - It is symmetric: for any non-null reference values
x
andy
,x.equals(y)
should returntrue
if and only ify.equals(x)
returnstrue
. - It is transitive: for any non-null reference values
x
,y
, andz
, ifx.equals(y)
returnstrue
andy.equals(z)
returnstrue
, thenx.equals(z)
should returntrue
. - It is consistent: for any non-null reference values
x
andy
, multiple invocations ofx.equals(y)
consistently returntrue
or consistently returnfalse
, provided no information used inequals
comparisons on the objects is modified. - For any non-null reference value
x
,x.equals(null)
should returnfalse
.
An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.
Parameters | |
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obj |
Object : the reference object with which to compare. |
Returns | |
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boolean |
true if this object is the same as the obj
argument; false otherwise. |
getBoundaryPath
public boolean getBoundaryPath (Path path)
Set the path to the boundary of the region. If the region is empty, the path will also be empty.
Parameters | |
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path |
Path : This value cannot be null . |
Returns | |
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boolean |
getBoundaryPath
public Path getBoundaryPath ()
Return the boundary of the region as a new Path. If the region is empty, the path will also be empty.
Returns | |
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Path |
This value cannot be null . |
getBounds
public Rect getBounds ()
Return a new Rect set to the bounds of the region. If the region is empty, the Rect will be set to [0, 0, 0, 0]
Returns | |
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Rect |
This value cannot be null . |
getBounds
public boolean getBounds (Rect r)
Set the Rect to the bounds of the region. If the region is empty, the Rect will be set to [0, 0, 0, 0]
Parameters | |
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r |
Rect : This value cannot be null . |
Returns | |
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boolean |
isComplex
public boolean isComplex ()
Return true if the region contains more than one rectangle
Returns | |
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boolean |
isEmpty
public boolean isEmpty ()
Return true if this region is empty
Returns | |
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boolean |
isRect
public boolean isRect ()
Return true if the region contains a single rectangle
Returns | |
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boolean |
op
public boolean op (Region region1, Region region2, Region.Op op)
Set this region to the result of performing the Op on the specified regions. Return true if the result is not empty.
Parameters | |
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region1 |
Region : This value cannot be null . |
region2 |
Region : This value cannot be null . |
op |
Region.Op : This value cannot be null . |
Returns | |
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boolean |
op
public boolean op (Rect r, Region.Op op)
Perform the specified Op on this region and the specified rect. Return true if the result of the op is not empty.
Parameters | |
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r |
Rect : This value cannot be null . |
op |
Region.Op : This value cannot be null . |
Returns | |
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boolean |
op
public boolean op (Rect rect, Region region, Region.Op op)
Set this region to the result of performing the Op on the specified rect and region. Return true if the result is not empty.
Parameters | |
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rect |
Rect : This value cannot be null . |
region |
Region : This value cannot be null . |
op |
Region.Op : This value cannot be null . |
Returns | |
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boolean |
op
public boolean op (Region region, Region.Op op)
Perform the specified Op on this region and the specified region. Return true if the result of the op is not empty.
Parameters | |
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region |
Region : This value cannot be null . |
op |
Region.Op : This value cannot be null . |
Returns | |
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boolean |
op
public boolean op (int left, int top, int right, int bottom, Region.Op op)
Perform the specified Op on this region and the specified rect. Return true if the result of the op is not empty.
Parameters | |
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left |
int |
top |
int |
right |
int |
bottom |
int |
op |
Region.Op : This value cannot be null . |
Returns | |
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boolean |
quickContains
public boolean quickContains (Rect r)
Return true if the region is a single rectangle (not complex) and it contains the specified rectangle. Returning false is not a guarantee that the rectangle is not contained by this region, but return true is a guarantee that the rectangle is contained by this region.
Parameters | |
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r |
Rect : This value cannot be null . |
Returns | |
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boolean |
quickContains
public boolean quickContains (int left, int top, int right, int bottom)
Return true if the region is a single rectangle (not complex) and it contains the specified rectangle. Returning false is not a guarantee that the rectangle is not contained by this region, but return true is a guarantee that the rectangle is contained by this region.
Parameters | |
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left |
int |
top |
int |
right |
int |
bottom |
int |
Returns | |
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boolean |
quickReject
public boolean quickReject (Region rgn)
Return true if the region is empty, or if the specified region does not intersect the region. Returning false is not a guarantee that they intersect, but returning true is a guarantee that they do not.
Parameters | |
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rgn |
Region |
Returns | |
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boolean |
quickReject
public boolean quickReject (Rect r)
Return true if the region is empty, or if the specified rectangle does not intersect the region. Returning false is not a guarantee that they intersect, but returning true is a guarantee that they do not.
Parameters | |
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r |
Rect : This value cannot be null . |
Returns | |
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boolean |
quickReject
public boolean quickReject (int left, int top, int right, int bottom)
Return true if the region is empty, or if the specified rectangle does not intersect the region. Returning false is not a guarantee that they intersect, but returning true is a guarantee that they do not.
Parameters | |
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left |
int |
top |
int |
right |
int |
bottom |
int |
Returns | |
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boolean |
set
public boolean set (int left, int top, int right, int bottom)
Set the region to the specified rectangle
Parameters | |
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left |
int |
top |
int |
right |
int |
bottom |
int |
Returns | |
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boolean |
set
public boolean set (Region region)
Set the region to the specified region.
Parameters | |
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region |
Region : This value cannot be null . |
Returns | |
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boolean |
set
public boolean set (Rect r)
Set the region to the specified rectangle
Parameters | |
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r |
Rect : This value cannot be null . |
Returns | |
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boolean |
setPath
public boolean setPath (Path path, Region clip)
Set the region to the area described by the path and clip. Return true if the resulting region is non-empty. This produces a region that is identical to the pixels that would be drawn by the path (with no antialiasing).
Parameters | |
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path |
Path : This value cannot be null . |
clip |
Region : This value cannot be null . |
Returns | |
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boolean |
toString
public String toString ()
Returns a string representation of the object.
Returns | |
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String |
a string representation of the object. |
translate
public void translate (int dx, int dy, Region dst)
Set the dst region to the result of translating this region by [dx, dy]. If this region is empty, then dst will be set to empty.
Parameters | |
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dx |
int |
dy |
int |
dst |
Region |
translate
public void translate (int dx, int dy)
Translate the region by [dx, dy]. If the region is empty, do nothing.
Parameters | |
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dx |
int |
dy |
int |
union
public final boolean union (Rect r)
Parameters | |
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r |
Rect : This value cannot be null . |
Returns | |
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boolean |
writeToParcel
public void writeToParcel (Parcel p, int flags)
Write the region and its pixels to the parcel. The region can be rebuilt from the parcel by calling CREATOR.createFromParcel().
Parameters | |
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p |
Parcel : Parcel object to write the region data into |
flags |
int : Additional flags about how the object should be written.
May be 0 or Parcelable.PARCELABLE_WRITE_RETURN_VALUE .
Value is either 0 or a combination of Parcelable.PARCELABLE_WRITE_RETURN_VALUE , and android.os.Parcelable.PARCELABLE_ELIDE_DUPLICATES |
Protected methods
finalize
protected void finalize ()
Called by the garbage collector on an object when garbage collection
determines that there are no more references to the object.
A subclass overrides the finalize
method to dispose of
system resources or to perform other cleanup.
The general contract of finalize
is that it is invoked
if and when the Java virtual
machine has determined that there is no longer any
means by which this object can be accessed by any thread that has
not yet died, except as a result of an action taken by the
finalization of some other object or class which is ready to be
finalized. The finalize
method may take any action, including
making this object available again to other threads; the usual purpose
of finalize
, however, is to perform cleanup actions before
the object is irrevocably discarded. For example, the finalize method
for an object that represents an input/output connection might perform
explicit I/O transactions to break the connection before the object is
permanently discarded.
The finalize
method of class Object
performs no
special action; it simply returns normally. Subclasses of
Object
may override this definition.
The Java programming language does not guarantee which thread will
invoke the finalize
method for any given object. It is
guaranteed, however, that the thread that invokes finalize will not
be holding any user-visible synchronization locks when finalize is
invoked. If an uncaught exception is thrown by the finalize method,
the exception is ignored and finalization of that object terminates.
After the finalize
method has been invoked for an object, no
further action is taken until the Java virtual machine has again
determined that there is no longer any means by which this object can
be accessed by any thread that has not yet died, including possible
actions by other objects or classes which are ready to be finalized,
at which point the object may be discarded.
The finalize
method is never invoked more than once by a Java
virtual machine for any given object.
Any exception thrown by the finalize
method causes
the finalization of this object to be halted, but is otherwise
ignored.
Throws | |
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Throwable |