CanvasGradient class
An opaque canvas object representing a gradient.
Created by calling createLinearGradient or createRadialGradient on a
CanvasRenderingContext2D object.
Example usage:
var canvas = new CanvasElement(width: 600, height: 600);
var ctx = canvas.context2D;
ctx.clearRect(0, 0, 600, 600);
ctx.save();
// Create radial gradient.
CanvasGradient gradient = ctx.createRadialGradient(0, 0, 0, 0, 0, 600);
gradient.addColorStop(0, '#000');
gradient.addColorStop(1, 'rgb(255, 255, 255)');
// Assign gradients to fill.
ctx.fillStyle = gradient;
// Draw a rectangle with a gradient fill.
ctx.fillRect(0, 0, 600, 600);
ctx.save();
document.body.children.add(canvas);
See also:
- CanvasGradient from MDN.
- CanvasGradient from whatwg.
- CanvasGradient from W3C.
@DocsEditable
/**
* An opaque canvas object representing a gradient.
*
* Created by calling [createLinearGradient] or [createRadialGradient] on a
* [CanvasRenderingContext2D] object.
*
* Example usage:
*
* var canvas = new CanvasElement(width: 600, height: 600);
* var ctx = canvas.context2D;
* ctx.clearRect(0, 0, 600, 600);
* ctx.save();
* // Create radial gradient.
* CanvasGradient gradient = ctx.createRadialGradient(0, 0, 0, 0, 0, 600);
* gradient.addColorStop(0, '#000');
* gradient.addColorStop(1, 'rgb(255, 255, 255)');
* // Assign gradients to fill.
* ctx.fillStyle = gradient;
* // Draw a rectangle with a gradient fill.
* ctx.fillRect(0, 0, 600, 600);
* ctx.save();
* document.body.children.add(canvas);
*
* See also:
*
* * [CanvasGradient](https://developer.mozilla.org/en-US/docs/DOM/CanvasGradient) from MDN.
* * [CanvasGradient](http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#canvasgradient) from whatwg.
* * [CanvasGradient](http://www.w3.org/TR/2010/WD-2dcontext-20100304/#canvasgradient) from W3C.
*/
@DomName('CanvasGradient')
class CanvasGradient native "CanvasGradient" {
/**
* Adds a color stop to this gradient at the offset.
*
* The [offset] can range between 0.0 and 1.0.
*
* See also:
*
* * [Multiple Color Stops](https://developer.mozilla.org/en-US/docs/CSS/linear-gradient#Gradient_with_multiple_color_stops) from MDN.
*/
@DomName('CanvasGradient.addColorStop')
@DocsEditable
void addColorStop(num offset, String color) native;
}
Extends
Interceptor > CanvasGradient
Properties
final int hashCode #
Get a hash code for this object.
All objects have hash codes. Hash codes are guaranteed to be the
same for objects that are equal when compared using the equality
operator ==. Other than that there are no guarantees about
the hash codes. They will not be consistent between runs and
there are no distribution guarantees.
If a subclass overrides hashCode it should override the
equality operator as well to maintain consistency.
int get hashCode => Primitives.objectHashCode(this);
Operators
bool operator ==(other) #
The equality operator.
The default behavior for all Objects is to return true if and
only if this and
other are the same object.
If a subclass overrides the equality operator it should override
the hashCode method as well to maintain consistency.
bool operator ==(other) => identical(this, other);
Methods
void addColorStop(num offset, String color) #
Adds a color stop to this gradient at the offset.
The offset can range between 0.0 and 1.0.
See also:
- Multiple Color Stops from MDN.
@DomName('CanvasGradient.addColorStop')
@DocsEditable
void addColorStop(num offset, String color) native;
dynamic noSuchMethod(Invocation invocation) #
noSuchMethod is invoked when users invoke a non-existant method
on an object. The name of the method and the arguments of the
invocation are passed to noSuchMethod in an Invocation.
If noSuchMethod returns a value, that value becomes the result of
the original invocation.
The default behavior of noSuchMethod is to throw a
noSuchMethodError.
dynamic noSuchMethod(Invocation invocation) {
throw new NoSuchMethodError(
this,
_symbolToString(invocation.memberName),
invocation.positionalArguments,
_symbolMapToStringMap(invocation.namedArguments));
}