Alignment class

A point within a rectangle.

Alignment(0.0, 0.0) represents the center of the rectangle. The distance from -1.0 to +1.0 is the distance from one side of the rectangle to the other side of the rectangle. Therefore, 2.0 units horizontally (or vertically) is equivalent to the width (or height) of the rectangle.

Alignment(-1.0, -1.0) represents the top left of the rectangle.

Alignment(1.0, 1.0) represents the bottom right of the rectangle.

Alignment(0.0, 3.0) represents a point that is horizontally centered with respect to the rectangle and vertically below the bottom of the rectangle by the height of the rectangle.

Alignment use visual coordinates, which means increasing x moves the point from left to right. To support layouts with a right-to-left TextDirection, consider using AlignmentDirectional, in which the direction the point moves when increasing the horizontal value depends on the TextDirection.

A variety of widgets use Alignment in their configuration, most notably:

See also:

Inheritance
Implemented by

Constructors

Alignment(double x, double y)
Creates an alignment. [...]
const

Properties

x double
The distance fraction in the horizontal direction. [...]
final
y double
The distance fraction in the vertical direction. [...]
final
hashCode int
The hash code for this object. [...]
read-only, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited

Methods

add(AlignmentGeometry other) AlignmentGeometry
Returns the sum of two AlignmentGeometry objects. [...]
alongOffset(Offset other) Offset
Returns the offset that is this fraction in the direction of the given offset.
alongSize(Size other) Offset
Returns the offset that is this fraction within the given size.
inscribe(Size size, Rect rect) Rect
Returns a rect of the given size, aligned within given rect as specified by this alignment. [...]
resolve(TextDirection direction) Alignment
Convert this instance into a Alignment, which uses literal coordinates (the x coordinate being explicitly a distance from the left). [...]
toString() String
withinRect(Rect rect) Offset
Returns the point that is this fraction within the given rect.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited

Operators

operator %(double other) Alignment
Computes the remainder in each dimension by the given factor.
operator *(double other) Alignment
Scales the Alignment in each dimension by the given factor.
operator +(Alignment other) Alignment
Returns the sum of two Alignments.
operator -(Alignment other) Alignment
Returns the difference between two Alignments.
operator /(double other) Alignment
Divides the Alignment in each dimension by the given factor.
operator unary-() Alignment
Returns the negation of the given Alignment.
operator ~/(double other) Alignment
Integer divides the Alignment in each dimension by the given factor.
operator ==(dynamic other) bool
The equality operator. [...]
inherited

Static Methods

lerp(Alignment a, Alignment b, double t) Alignment
Linearly interpolate between two Alignments. [...]

Constants

bottomCenter → const Alignment
The center point along the bottom edge.
const Alignment(0.0, 1.0)
bottomLeft → const Alignment
The bottom left corner.
const Alignment(-1.0, 1.0)
bottomRight → const Alignment
The bottom right corner.
const Alignment(1.0, 1.0)
center → const Alignment
The center point, both horizontally and vertically.
const Alignment(0.0, 0.0)
centerLeft → const Alignment
The center point along the left edge.
const Alignment(-1.0, 0.0)
centerRight → const Alignment
The center point along the right edge.
const Alignment(1.0, 0.0)
topCenter → const Alignment
The center point along the top edge.
const Alignment(0.0, -1.0)
topLeft → const Alignment
The top left corner.
const Alignment(-1.0, -1.0)
topRight → const Alignment
The top right corner.
const Alignment(1.0, -1.0)