问题
I am having trouble replicating a normal settings menu in Flutter. I am using an InkWell to try to create the splash effect that normally occurs when you tap on a settings option. The problem is that the splash effect appears way too fast compared to how it normally is. Basically, I just want to slow down the InkWell.
回答1:
It's possible to create what you wanted but it requires a custom splashFactory under InkWell class.
As you see in the variables below, these are meant to be private values and they are not open to modification within classes.
const Duration _kUnconfirmedSplashDuration = const Duration(seconds: 1);
const Duration _kSplashFadeDuration = const Duration(milliseconds: 200);
const double _kSplashInitialSize = 0.0; // logical pixels
const double _kSplashConfirmedVelocity = 1.0;
To answer your question, yes you can do it. I just copied and pasted everything from the source code and change the animation values. After the code below just use it in splashFactory.
///Part to use within application
new InkWell(
onTap: () {},
splashFactory: CustomSplashFactory(),
child: Container(
padding: EdgeInsets.all(12.0),
child: Text('Flat Button'),
),
//Part to copy from the source code.
const Duration _kUnconfirmedSplashDuration = const Duration(seconds: 10);
const Duration _kSplashFadeDuration = const Duration(seconds: 2);
const double _kSplashInitialSize = 0.0; // logical pixels
const double _kSplashConfirmedVelocity = 0.1;
class CustomSplashFactory extends InteractiveInkFeatureFactory {
const CustomSplashFactory();
@override
InteractiveInkFeature create({
@required MaterialInkController controller,
@required RenderBox referenceBox,
@required Offset position,
@required Color color,
bool containedInkWell = false,
RectCallback rectCallback,
BorderRadius borderRadius,
double radius,
VoidCallback onRemoved,
}) {
return new CustomSplash(
controller: controller,
referenceBox: referenceBox,
position: position,
color: color,
containedInkWell: containedInkWell,
rectCallback: rectCallback,
borderRadius: borderRadius,
radius: radius,
onRemoved: onRemoved,
);
}
}
class CustomSplash extends InteractiveInkFeature {
/// Used to specify this type of ink splash for an [InkWell], [InkResponse]
/// or material [Theme].
static const InteractiveInkFeatureFactory splashFactory = const CustomSplashFactory();
/// Begin a splash, centered at position relative to [referenceBox].
///
/// The [controller] argument is typically obtained via
/// `Material.of(context)`.
///
/// If `containedInkWell` is true, then the splash will be sized to fit
/// the well rectangle, then clipped to it when drawn. The well
/// rectangle is the box returned by `rectCallback`, if provided, or
/// otherwise is the bounds of the [referenceBox].
///
/// If `containedInkWell` is false, then `rectCallback` should be null.
/// The ink splash is clipped only to the edges of the [Material].
/// This is the default.
///
/// When the splash is removed, `onRemoved` will be called.
CustomSplash({
@required MaterialInkController controller,
@required RenderBox referenceBox,
Offset position,
Color color,
bool containedInkWell = false,
RectCallback rectCallback,
BorderRadius borderRadius,
double radius,
VoidCallback onRemoved,
}) : _position = position,
_borderRadius = borderRadius ?? BorderRadius.zero,
_targetRadius = radius ?? _getTargetRadius(referenceBox, containedInkWell, rectCallback, position),
_clipCallback = _getClipCallback(referenceBox, containedInkWell, rectCallback),
_repositionToReferenceBox = !containedInkWell,
super(controller: controller, referenceBox: referenceBox, color: color, onRemoved: onRemoved) {
assert(_borderRadius != null);
_radiusController = new AnimationController(duration: _kUnconfirmedSplashDuration, vsync: controller.vsync)
..addListener(controller.markNeedsPaint)
..forward();
_radius = new Tween<double>(
begin: _kSplashInitialSize,
end: _targetRadius
).animate(_radiusController);
_alphaController = new AnimationController(duration: _kSplashFadeDuration, vsync: controller.vsync)
..addListener(controller.markNeedsPaint)
..addStatusListener(_handleAlphaStatusChanged);
_alpha = new IntTween(
begin: color.alpha,
end: 0
).animate(_alphaController);
controller.addInkFeature(this);
}
final Offset _position;
final BorderRadius _borderRadius;
final double _targetRadius;
final RectCallback _clipCallback;
final bool _repositionToReferenceBox;
Animation<double> _radius;
AnimationController _radiusController;
Animation<int> _alpha;
AnimationController _alphaController;
@override
void confirm() {
final int duration = (_targetRadius / _kSplashConfirmedVelocity).floor();
_radiusController
..duration = new Duration(milliseconds: duration)
..forward();
_alphaController.forward();
}
@override
void cancel() {
_alphaController?.forward();
}
void _handleAlphaStatusChanged(AnimationStatus status) {
if (status == AnimationStatus.completed)
dispose();
}
@override
void dispose() {
_radiusController.dispose();
_alphaController.dispose();
_alphaController = null;
super.dispose();
}
RRect _clipRRectFromRect(Rect rect) {
return new RRect.fromRectAndCorners(
rect,
topLeft: _borderRadius.topLeft, topRight: _borderRadius.topRight,
bottomLeft: _borderRadius.bottomLeft, bottomRight: _borderRadius.bottomRight,
);
}
void _clipCanvasWithRect(Canvas canvas, Rect rect, {Offset offset}) {
Rect clipRect = rect;
if (offset != null) {
clipRect = clipRect.shift(offset);
}
if (_borderRadius != BorderRadius.zero) {
canvas.clipRRect(_clipRRectFromRect(clipRect));
} else {
canvas.clipRect(clipRect);
}
}
@override
void paintFeature(Canvas canvas, Matrix4 transform) {
final Paint paint = new Paint()..color = color.withAlpha(_alpha.value);
Offset center = _position;
if (_repositionToReferenceBox)
center = Offset.lerp(center, referenceBox.size.center(Offset.zero), _radiusController.value);
final Offset originOffset = MatrixUtils.getAsTranslation(transform);
if (originOffset == null) {
canvas.save();
canvas.transform(transform.storage);
if (_clipCallback != null) {
_clipCanvasWithRect(canvas, _clipCallback());
}
canvas.drawCircle(center, _radius.value, paint);
canvas.restore();
} else {
if (_clipCallback != null) {
canvas.save();
_clipCanvasWithRect(canvas, _clipCallback(), offset: originOffset);
}
canvas.drawCircle(center + originOffset, _radius.value, paint);
if (_clipCallback != null)
canvas.restore();
}
}
}
double _getTargetRadius(RenderBox referenceBox, bool containedInkWell, RectCallback rectCallback, Offset position) {
if (containedInkWell) {
final Size size = rectCallback != null ? rectCallback().size : referenceBox.size;
return _getSplashRadiusForPositionInSize(size, position);
}
return Material.defaultSplashRadius;
}
double _getSplashRadiusForPositionInSize(Size bounds, Offset position) {
final double d1 = (position - bounds.topLeft(Offset.zero)).distance;
final double d2 = (position - bounds.topRight(Offset.zero)).distance;
final double d3 = (position - bounds.bottomLeft(Offset.zero)).distance;
final double d4 = (position - bounds.bottomRight(Offset.zero)).distance;
return math.max(math.max(d1, d2), math.max(d3, d4)).ceilToDouble();
}
RectCallback _getClipCallback(RenderBox referenceBox, bool containedInkWell, RectCallback rectCallback) {
if (rectCallback != null) {
assert(containedInkWell);
return rectCallback;
}
if (containedInkWell)
return () => Offset.zero & referenceBox.size;
return null;
}
回答2:
If you would like a slower ripple effect, then you have to change splashFactory property in your MaterialApp theme from InkSplash.splashFactory (default) to InkRipple.splashFactory. InkRipple's splash looks more like native.
来源：https://stackoverflow.com/questions/51115401/changing-speed-of-inkwell