Android
android.graphics
public class

android.graphics.Path

java.lang.Object
android.graphics.Path

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.

Nested Classes
Path.Direction Specifies how closed shapes (e.g. 
Path.FillType Enum for the ways a path may be filled  

Summary

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, Matrix matrix)
Add a copy of src to the path, transformed by matrix
          void  addPath(Path src)
Add a copy of src to the path
          void  addPath(Path src, float dx, float dy)
Add a copy of src to the path, offset by (dx,dy)
          void  addRect(RectF rect, Path.Direction dir)
Add a closed rectangle contour to the path
          void  addRect(float left, float top, float right, float bottom, 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, boolean forceMoveTo)
Append the specified arc to the path as a new contour.
          void  arcTo(RectF oval, float startAngle, float sweepAngle)
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 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)
Offset the path by (dx,dy), returning true on success
          void  offset(float dx, float dy, Path dst)
Offset the path by (dx,dy), returning true on success
          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)
Transform the points in this path by matrix.
          void  transform(Matrix matrix, Path dst)
Transform the points in this path by matrix, and write the answer into dst.

Protected Methods

          void  finalize()
Called by the virtual machine when there are no longer any (non-weak) references to the receiver.
Methods inherited from class java.lang.Object

Details

Public Constructors

public Path()

Create an empty path

public Path(Path src)

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)

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)

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)

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, Matrix matrix)

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

Parameters

src The path to add as a new contour

public void addPath(Path src)

Add a copy of src to the path

Parameters

src The path that is appended to the current path

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

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 addRect(RectF rect, Path.Direction dir)

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

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

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)

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, boolean forceMoveTo)

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 arcTo(RectF oval, float startAngle, float sweepAngle)

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 close()

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)

Compute the bounds 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
exact If true, return the exact (but slower) bounds, else return just the bounds of all control points

public 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). 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()

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)

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()

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()

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)

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)

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)

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)

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

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 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). 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)

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)

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)

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)

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()

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

public void rewind()

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)

Replace the contents of this with the contents of src.

public void setFillType(Path.FillType ft)

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)

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()

Toggles the INVERSE state of the filltype

public void transform(Matrix matrix)

Transform the points in this path by matrix.

Parameters

matrix The matrix to apply to the path

public void transform(Matrix matrix, Path dst)

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

Protected Methods

protected void finalize()

Called by the virtual machine when there are no longer any (non-weak) references to the receiver. Subclasses can use this facility to guarantee that any associated resources are cleaned up before the receiver is garbage collected. Uncaught exceptions which are thrown during the running of the method cause it to terminate immediately, but are otherwise ignored.

Note: The virtual machine assumes that the implementation in class Object is empty.

Throws

Throwable
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