public static Task <bool> AnimateRowHeightAsync(
this Grid view,
RowDefinition rowDefinition,
double rowExpandedHeight,
bool isVisible,
string animationName,
bool dontAnimate = false)
{
const double Tolerance = 2f;
var tcs = new TaskCompletionSource <bool>();
Animation animation;
if (view.AbortAnimation(animationName))
{
}
if (isVisible)
{
if (dontAnimate)
{
rowDefinition.Height = rowExpandedHeight;
tcs.SetResult(true);
return(tcs.Task);
}
if (rowDefinition.Height.Value > (rowExpandedHeight - Tolerance))
{
tcs.SetResult(false);
return(tcs.Task);
}
// Move back to original height
animation = new Animation(
d => rowDefinition.Height = new GridLength(Clamp(d, 0, double.MaxValue)),
rowDefinition.Height.Value,
rowExpandedHeight,
Easing.Linear,
() => animation = null);
}
else
{
if (dontAnimate)
{
rowDefinition.Height = ZeroHeightGrid;
tcs.SetResult(true);
return(tcs.Task);
}
if (Math.Abs(rowDefinition.Height.Value) < Tolerance)
{
tcs.SetResult(false);
return(tcs.Task);
}
// Hide the row
animation = new Animation(
d => rowDefinition.Height = new GridLength(Clamp(d, 0, double.MaxValue)),
rowExpandedHeight,
0,
Easing.Linear,
() => animation = null);
}
try
{
view.Animate(
animationName,
animation,
length: 400,
finished: (value, success) => tcs.TrySetResult(success));
}
catch (Exception)
{
tcs.SetResult(false);
}
return(tcs.Task);
}