Skip to content

Most visited

Recently visited

navigation

PathMeasure

public class PathMeasure
extends Object

java.lang.Object
   ↳ android.graphics.PathMeasure


Summary

Constants

int POSITION_MATRIX_FLAG

int TANGENT_MATRIX_FLAG

Public constructors

PathMeasure()

Create an empty PathMeasure object.

PathMeasure(Path path, boolean forceClosed)

Create a PathMeasure object associated with the specified path object (already created and specified).

Public methods

float getLength()

Return the total length of the current contour, or 0 if no path is associated with this measure object.

boolean getMatrix(float distance, Matrix matrix, int flags)

Pins distance to 0 <= distance <= getLength(), and then computes the corresponding matrix.

boolean getPosTan(float distance, float[] pos, float[] tan)

Pins distance to 0 <= distance <= getLength(), and then computes the corresponding position and tangent.

boolean getSegment(float startD, float stopD, Path dst, boolean startWithMoveTo)

Given a start and stop distance, return in dst the intervening segment(s).

boolean isClosed()

Return true if the current contour is closed()

boolean nextContour()

Move to the next contour in the path.

void setPath(Path path, boolean forceClosed)

Assign a new path, or null to have none.

Protected methods

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

From class java.lang.Object

Constants

POSITION_MATRIX_FLAG

Added in API level 1
int POSITION_MATRIX_FLAG

Constant Value: 1 (0x00000001)

TANGENT_MATRIX_FLAG

Added in API level 1
int TANGENT_MATRIX_FLAG

Constant Value: 2 (0x00000002)

Public constructors

PathMeasure

Added in API level 1
PathMeasure ()

Create an empty PathMeasure object. To uses this to measure the length of a path, and/or to find the position and tangent along it, call setPath. Note that once a path is associated with the measure object, it is undefined if the path is subsequently modified and the the measure object is used. If the path is modified, you must call setPath with the path.

PathMeasure

Added in API level 1
PathMeasure (Path path, 
                boolean forceClosed)

Create a PathMeasure object associated with the specified path object (already created and specified). The measure object can now return the path's length, and the position and tangent of any position along the path. Note that once a path is associated with the measure object, it is undefined if the path is subsequently modified and the the measure object is used. If the path is modified, you must call setPath with the path.

Parameters
path Path: The path that will be measured by this object
forceClosed boolean: If true, then the path will be considered as "closed" even if its contour was not explicitly closed.

Public methods

getLength

Added in API level 1
float getLength ()

Return the total length of the current contour, or 0 if no path is associated with this measure object.

Returns
float

getMatrix

Added in API level 1
boolean getMatrix (float distance, 
                Matrix matrix, 
                int flags)

Pins distance to 0 <= distance <= getLength(), and then computes the corresponding matrix. Returns false if there is no path, or a zero-length path was specified, in which case matrix is unchanged.

Parameters
distance float: The distance along the associated path
matrix Matrix: Allocated by the caller, this is set to the transformation associated with the position and tangent at the specified distance
flags int: Specified what aspects should be returned in the matrix.
Returns
boolean

getPosTan

Added in API level 1
boolean getPosTan (float distance, 
                float[] pos, 
                float[] tan)

Pins distance to 0 <= distance <= getLength(), and then computes the corresponding position and tangent. Returns false if there is no path, or a zero-length path was specified, in which case position and tangent are unchanged.

Parameters
distance float: The distance along the current contour to sample
pos float: If not null, eturns the sampled position (x==[0], y==[1])
tan float: If not null, returns the sampled tangent (x==[0], y==[1])
Returns
boolean false if there was no path associated with this measure object

getSegment

Added in API level 1
boolean getSegment (float startD, 
                float stopD, 
                Path dst, 
                boolean startWithMoveTo)

Given a start and stop distance, return in dst the intervening segment(s). If the segment is zero-length, return false, else return true. startD and stopD are pinned to legal values (0..getLength()). If startD >= stopD then return false (and leave dst untouched). Begin the segment with a moveTo if startWithMoveTo is true.

On KITKAT and earlier releases, the resulting path may not display on a hardware-accelerated Canvas. A simple workaround is to add a single operation to this path, such as dst.rLineTo(0, 0).

Parameters
startD float
stopD float
dst Path
startWithMoveTo boolean
Returns
boolean

isClosed

Added in API level 1
boolean isClosed ()

Return true if the current contour is closed()

Returns
boolean

nextContour

Added in API level 1
boolean nextContour ()

Move to the next contour in the path. Return true if one exists, or false if we're done with the path.

Returns
boolean

setPath

Added in API level 1
void setPath (Path path, 
                boolean forceClosed)

Assign a new path, or null to have none.

Parameters
path Path
forceClosed boolean

Protected methods

finalize

Added in API level 1
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 JavaTM 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
Throwable
This site uses cookies to store your preferences for site-specific language and display options.

Hooray!

This class requires API level or higher

This doc is hidden because your selected API level for the documentation is . You can change the documentation API level with the selector above the left navigation.

For more information about specifying the API level your app requires, read Supporting Different Platform Versions.