private void _handleOnScaleEnd(ScaleEndDetails details)
{
float magnitude = details.velocity.pixelsPerSecond.distance;
if (magnitude < GridListDemoUtils._kMinFlingVelocity)
{
return;
}
Offset direction = details.velocity.pixelsPerSecond / magnitude;
float distance = (Offset.zero & context.size).shortestSide;
_flingAnimation = _controller.drive(new OffsetTween(
begin: _offset,
end: _clampOffset(_offset + direction * distance)
));
_controller.setValue(0.0f);
_controller.fling(velocity: magnitude / 1000.0f);
}
void _onScaleEnd(ScaleEndDetails scaleEndDetails)
{
if (this._scale > this._effectiveMaxScale)
{
this._scaleAndMoveToClamped(
targetScale: this._effectiveMaxScale,
this._position + this._initialPosition *
(this._scale - this._effectiveMaxScale) / this._initialScale);
this._positionAnimationController.setValue(0);
this._positionAnimationController.animateTo(1);
}
else if (this._scale < this._effectiveMinScale)
{
this._scaleAndMoveTo(targetScale: this._effectiveMinScale, targetPosition: Offset.zero);
this._positionAnimationController.setValue(0);
this._positionAnimationController.animateTo(1);
}
else
{
if (this._panning && scaleEndDetails.velocity != null)
{
var velocity = scaleEndDetails.velocity.clampMagnitude(0, maxValue: this.widget.maxVelocity)
.pixelsPerSecond;
var duration = velocity.distance / this.widget.deceleration;
velocity = this._toFractional(offset: velocity);
this._inertiaAnimationController.duration = TimeSpan.FromSeconds(value: duration);
this._positionAnimation = new OffsetTween(
begin: this._position,
this._position + velocity * duration / 2)
.animate(parent: this._inertiaAnimationController);
this._inertiaAnimationController.setValue(0);
this._inertiaAnimationController.animateTo(1, curve: Curves.decelerate);
}
}
this._scaleAnimationController.setValue(0);
this._scaleAnimationController.animateTo(1);
this._panning = false;
this._scaling = false;
}