Android APIs
public class

Path

extends Object
java.lang.Object
   ↳ android.graphics.Path

Class Overview

The Path class encapsulates compound (multiple contour) geometric paths consisting of straight line segments, quadratic curves, and cubic curves. It can be drawn with canvas.drawPath(path, paint), either filled or stroked (based on the paint's Style), or it can be used for clipping or to draw text on a path.

Summary

Nested Classes
enum Path.Direction Specifies how closed shapes (e.g. 
enum Path.FillType Enum for the ways a path may be filled. 
enum Path.Op The logical operations that can be performed when combining two paths. 
Public Constructors
Path()
Create an empty path
Path(Path src)
Create a new path, copying the contents from the src path.
Public Methods
void addArc(RectF oval, float startAngle, float sweepAngle)
Add the specified arc to the path as a new contour.
void addCircle(float x, float y, float radius, Path.Direction dir)
Add a closed circle contour to the path
void addOval(RectF oval, Path.Direction dir)
Add a closed oval contour to the path
void addPath(Path src, float dx, float dy)
Add a copy of src to the path, offset by (dx,dy)
void addPath(Path src)
Add a copy of src to the path
void addPath(Path src, Matrix matrix)
Add a copy of src to the path, transformed by matrix
void addRect(float left, float top, float right, float bottom, Path.Direction dir)
Add a closed rectangle contour to the path
void addRect(RectF rect, Path.Direction dir)
Add a closed rectangle contour to the path
void addRoundRect(RectF rect, float[] radii, Path.Direction dir)
Add a closed round-rectangle contour to the path.
void addRoundRect(RectF rect, float rx, float ry, Path.Direction dir)
Add a closed round-rectangle contour to the path
void arcTo(RectF oval, float startAngle, float sweepAngle)
Append the specified arc to the path as a new contour.
void arcTo(RectF oval, float startAngle, float sweepAngle, boolean forceMoveTo)
Append the specified arc to the path as a new contour.
void close()
Close the current contour.
void computeBounds(RectF bounds, boolean exact)
Compute the bounds of the control points of the path, and write the answer into bounds.
void cubicTo(float x1, float y1, float x2, float y2, float x3, float y3)
Add a cubic bezier from the last point, approaching control points (x1,y1) and (x2,y2), and ending at (x3,y3).
Path.FillType getFillType()
Return the path's fill type.
void incReserve(int extraPtCount)
Hint to the path to prepare for adding more points.
boolean isEmpty()
Returns true if the path is empty (contains no lines or curves)
boolean isInverseFillType()
Returns true if the filltype is one of the INVERSE variants
boolean isRect(RectF rect)
Returns true if the path specifies a rectangle.
void lineTo(float x, float y)
Add a line from the last point to the specified point (x,y).
void moveTo(float x, float y)
Set the beginning of the next contour to the point (x,y).
void offset(float dx, float dy, Path dst)
Offset the path by (dx,dy), returning true on success
void offset(float dx, float dy)
Offset the path by (dx,dy), returning true on success
boolean op(Path path1, Path path2, Path.Op op)
Set this path to the result of applying the Op to the two specified paths.
boolean op(Path path, Path.Op op)
Set this path to the result of applying the Op to this path and the specified path.
void quadTo(float x1, float y1, float x2, float y2)
Add a quadratic bezier from the last point, approaching control point (x1,y1), and ending at (x2,y2).
void rCubicTo(float x1, float y1, float x2, float y2, float x3, float y3)
Same as cubicTo, but the coordinates are considered relative to the current point on this contour.
void rLineTo(float dx, float dy)
Same as lineTo, but the coordinates are considered relative to the last point on this contour.
void rMoveTo(float dx, float dy)
Set the beginning of the next contour relative to the last point on the previous contour.
void rQuadTo(float dx1, float dy1, float dx2, float dy2)
Same as quadTo, but the coordinates are considered relative to the last point on this contour.
void reset()
Clear any lines and curves from the path, making it empty.
void rewind()
Rewinds the path: clears any lines and curves from the path but keeps the internal data structure for faster reuse.
void set(Path src)
Replace the contents of this with the contents of src.
void setFillType(Path.FillType ft)
Set the path's fill type.
void setLastPoint(float dx, float dy)
Sets the last point of the path.
void toggleInverseFillType()
Toggles the INVERSE state of the filltype
void transform(Matrix matrix, Path dst)
Transform the points in this path by matrix, and write the answer into dst.
void transform(Matrix matrix)
Transform the points in this path by matrix.
Protected Methods
void finalize()
Invoked when the garbage collector has detected that this instance is no longer reachable.
[Expand]
Inherited Methods
From class java.lang.Object

Public Constructors

public Path ()

Added in API level 1

Create an empty path

public Path (Path src)

Added in API level 1

Create a new path, copying the contents from the src path.

Parameters
src The path to copy from when initializing the new path

Public Methods

public void addArc (RectF oval, float startAngle, float sweepAngle)

Added in API level 1

Add the specified arc to the path as a new contour.

Parameters
oval The bounds of oval defining the shape and size of the arc
startAngle Starting angle (in degrees) where the arc begins
sweepAngle Sweep angle (in degrees) measured clockwise

public void addCircle (float x, float y, float radius, Path.Direction dir)

Added in API level 1

Add a closed circle contour to the path

Parameters
x The x-coordinate of the center of a circle to add to the path
y The y-coordinate of the center of a circle to add to the path
radius The radius of a circle to add to the path
dir The direction to wind the circle's contour

public void addOval (RectF oval, Path.Direction dir)

Added in API level 1

Add a closed oval contour to the path

Parameters
oval The bounds of the oval to add as a closed contour to the path
dir The direction to wind the oval's contour

public void addPath (Path src, float dx, float dy)

Added in API level 1

Add a copy of src to the path, offset by (dx,dy)

Parameters
src The path to add as a new contour
dx The amount to translate the path in X as it is added

public void addPath (Path src)

Added in API level 1

Add a copy of src to the path

Parameters
src The path that is appended to the current path

public void addPath (Path src, Matrix matrix)

Added in API level 1

Add a copy of src to the path, transformed by matrix

Parameters
src The path to add as a new contour

public void addRect (float left, float top, float right, float bottom, Path.Direction dir)

Added in API level 1

Add a closed rectangle contour to the path

Parameters
left The left side of a rectangle to add to the path
top The top of a rectangle to add to the path
right The right side of a rectangle to add to the path
bottom The bottom of a rectangle to add to the path
dir The direction to wind the rectangle's contour

public void addRect (RectF rect, Path.Direction dir)

Added in API level 1

Add a closed rectangle contour to the path

Parameters
rect The rectangle to add as a closed contour to the path
dir The direction to wind the rectangle's contour

public void addRoundRect (RectF rect, float[] radii, Path.Direction dir)

Added in API level 1

Add a closed round-rectangle contour to the path. Each corner receives two radius values [X, Y]. The corners are ordered top-left, top-right, bottom-right, bottom-left

Parameters
rect The bounds of a round-rectangle to add to the path
radii Array of 8 values, 4 pairs of [X,Y] radii
dir The direction to wind the round-rectangle's contour

public void addRoundRect (RectF rect, float rx, float ry, Path.Direction dir)

Added in API level 1

Add a closed round-rectangle contour to the path

Parameters
rect The bounds of a round-rectangle to add to the path
rx The x-radius of the rounded corners on the round-rectangle
ry The y-radius of the rounded corners on the round-rectangle
dir The direction to wind the round-rectangle's contour

public void arcTo (RectF oval, float startAngle, float sweepAngle)

Added in API level 1

Append the specified arc to the path as a new contour. If the start of the path is different from the path's current last point, then an automatic lineTo() is added to connect the current contour to the start of the arc. However, if the path is empty, then we call moveTo() with the first point of the arc.

Parameters
oval The bounds of oval defining shape and size of the arc
startAngle Starting angle (in degrees) where the arc begins
sweepAngle Sweep angle (in degrees) measured clockwise

public void arcTo (RectF oval, float startAngle, float sweepAngle, boolean forceMoveTo)

Added in API level 1

Append the specified arc to the path as a new contour. If the start of the path is different from the path's current last point, then an automatic lineTo() is added to connect the current contour to the start of the arc. However, if the path is empty, then we call moveTo() with the first point of the arc. The sweep angle is tread mod 360.

Parameters
oval The bounds of oval defining shape and size of the arc
startAngle Starting angle (in degrees) where the arc begins
sweepAngle Sweep angle (in degrees) measured clockwise, treated mod 360.
forceMoveTo If true, always begin a new contour with the arc

public void close ()

Added in API level 1

Close the current contour. If the current point is not equal to the first point of the contour, a line segment is automatically added.

public void computeBounds (RectF bounds, boolean exact)

Added in API level 1

Compute the bounds of the control points of the path, and write the answer into bounds. If the path contains 0 or 1 points, the bounds is set to (0,0,0,0)

Parameters
bounds Returns the computed bounds of the path's control points.
exact This parameter is no longer used.

public void cubicTo (float x1, float y1, float x2, float y2, float x3, float y3)

Added in API level 1

Add a cubic bezier from the last point, approaching control points (x1,y1) and (x2,y2), and ending at (x3,y3). If no moveTo() call has been made for this contour, the first point is automatically set to (0,0).

Parameters
x1 The x-coordinate of the 1st control point on a cubic curve
y1 The y-coordinate of the 1st control point on a cubic curve
x2 The x-coordinate of the 2nd control point on a cubic curve
y2 The y-coordinate of the 2nd control point on a cubic curve
x3 The x-coordinate of the end point on a cubic curve
y3 The y-coordinate of the end point on a cubic curve

public Path.FillType getFillType ()

Added in API level 1

Return the path's fill type. This defines how "inside" is computed. The default value is WINDING.

Returns
  • the path's fill type

public void incReserve (int extraPtCount)

Added in API level 1

Hint to the path to prepare for adding more points. This can allow the path to more efficiently allocate its storage.

Parameters
extraPtCount The number of extra points that may be added to this path

public boolean isEmpty ()

Added in API level 1

Returns true if the path is empty (contains no lines or curves)

Returns
  • true if the path is empty (contains no lines or curves)

public boolean isInverseFillType ()

Added in API level 1

Returns true if the filltype is one of the INVERSE variants

Returns
  • true if the filltype is one of the INVERSE variants

public boolean isRect (RectF rect)

Added in API level 1

Returns true if the path specifies a rectangle. If so, and if rect is not null, set rect to the bounds of the path. If the path does not specify a rectangle, return false and ignore rect.

Parameters
rect If not null, returns the bounds of the path if it specifies a rectangle
Returns
  • true if the path specifies a rectangle

public void lineTo (float x, float y)

Added in API level 1

Add a line from the last point to the specified point (x,y). If no moveTo() call has been made for this contour, the first point is automatically set to (0,0).

Parameters
x The x-coordinate of the end of a line
y The y-coordinate of the end of a line

public void moveTo (float x, float y)

Added in API level 1

Set the beginning of the next contour to the point (x,y).

Parameters
x The x-coordinate of the start of a new contour
y The y-coordinate of the start of a new contour

public void offset (float dx, float dy, Path dst)

Added in API level 1

Offset the path by (dx,dy), returning true on success

Parameters
dx The amount in the X direction to offset the entire path
dy The amount in the Y direction to offset the entire path
dst The translated path is written here. If this is null, then the original path is modified.

public void offset (float dx, float dy)

Added in API level 1

Offset the path by (dx,dy), returning true on success

Parameters
dx The amount in the X direction to offset the entire path
dy The amount in the Y direction to offset the entire path

public boolean op (Path path1, Path path2, Path.Op op)

Added in API level 19

Set this path to the result of applying the Op to the two specified paths. The resulting path will be constructed from non-overlapping contours. The curve order is reduced where possible so that cubics may be turned into quadratics, and quadratics maybe turned into lines.

Parameters
path1 The first operand (for difference, the minuend)
path2 The second operand (for difference, the subtrahend)
Returns
  • True if operation succeeded, false otherwise and this path remains unmodified.

public boolean op (Path path, Path.Op op)

Added in API level 19

Set this path to the result of applying the Op to this path and the specified path. The resulting path will be constructed from non-overlapping contours. The curve order is reduced where possible so that cubics may be turned into quadratics, and quadratics maybe turned into lines.

Parameters
path The second operand (for difference, the subtrahend)
Returns
  • True if operation succeeded, false otherwise and this path remains unmodified.

public void quadTo (float x1, float y1, float x2, float y2)

Added in API level 1

Add a quadratic bezier from the last point, approaching control point (x1,y1), and ending at (x2,y2). If no moveTo() call has been made for this contour, the first point is automatically set to (0,0).

Parameters
x1 The x-coordinate of the control point on a quadratic curve
y1 The y-coordinate of the control point on a quadratic curve
x2 The x-coordinate of the end point on a quadratic curve
y2 The y-coordinate of the end point on a quadratic curve

public void rCubicTo (float x1, float y1, float x2, float y2, float x3, float y3)

Added in API level 1

Same as cubicTo, but the coordinates are considered relative to the current point on this contour. If there is no previous point, then a moveTo(0,0) is inserted automatically.

public void rLineTo (float dx, float dy)

Added in API level 1

Same as lineTo, but the coordinates are considered relative to the last point on this contour. If there is no previous point, then a moveTo(0,0) is inserted automatically.

Parameters
dx The amount to add to the x-coordinate of the previous point on this contour, to specify a line
dy The amount to add to the y-coordinate of the previous point on this contour, to specify a line

public void rMoveTo (float dx, float dy)

Added in API level 1

Set the beginning of the next contour relative to the last point on the previous contour. If there is no previous contour, this is treated the same as moveTo().

Parameters
dx The amount to add to the x-coordinate of the end of the previous contour, to specify the start of a new contour
dy The amount to add to the y-coordinate of the end of the previous contour, to specify the start of a new contour

public void rQuadTo (float dx1, float dy1, float dx2, float dy2)

Added in API level 1

Same as quadTo, but the coordinates are considered relative to the last point on this contour. If there is no previous point, then a moveTo(0,0) is inserted automatically.

Parameters
dx1 The amount to add to the x-coordinate of the last point on this contour, for the control point of a quadratic curve
dy1 The amount to add to the y-coordinate of the last point on this contour, for the control point of a quadratic curve
dx2 The amount to add to the x-coordinate of the last point on this contour, for the end point of a quadratic curve
dy2 The amount to add to the y-coordinate of the last point on this contour, for the end point of a quadratic curve

public void reset ()

Added in API level 1

Clear any lines and curves from the path, making it empty. This does NOT change the fill-type setting.

public void rewind ()

Added in API level 1

Rewinds the path: clears any lines and curves from the path but keeps the internal data structure for faster reuse.

public void set (Path src)

Added in API level 1

Replace the contents of this with the contents of src.

public void setFillType (Path.FillType ft)

Added in API level 1

Set the path's fill type. This defines how "inside" is computed.

Parameters
ft The new fill type for this path

public void setLastPoint (float dx, float dy)

Added in API level 1

Sets the last point of the path.

Parameters
dx The new X coordinate for the last point
dy The new Y coordinate for the last point

public void toggleInverseFillType ()

Added in API level 1

Toggles the INVERSE state of the filltype

public void transform (Matrix matrix, Path dst)

Added in API level 1

Transform the points in this path by matrix, and write the answer into dst. If dst is null, then the the original path is modified.

Parameters
matrix The matrix to apply to the path
dst The transformed path is written here. If dst is null, then the the original path is modified

public void transform (Matrix matrix)

Added in API level 1

Transform the points in this path by matrix.

Parameters
matrix The matrix to apply to the path

Protected Methods

protected void finalize ()

Added in API level 1

Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.

Throws
Throwable