private async Task HandleTouchCompleted()
{
if (itemIndex >= ItemsSource.Count)
{
return;
}
var topCard = CardStack.Children[numberOfCards - 1];
var backCard = CardStack.Children[numberOfCards - 2];
// Check if card has been dragged far enough to trigger action
if (Math.Abs(cardDistance) >= CardMoveDistance)
{
// Move card off the screen
await topCard.TranslateTo(cardDistance > 0?this.Width : -this.Width, 0, animationLength / 2, Easing.SpringOut);
topCard.IsVisible = false;
// Fire events
if (cardDistance > 0)
{
SwipedRight?.Invoke(ItemsSource[itemIndex]);
if (SwipedRightCommand != null && SwipedRightCommand.CanExecute(ItemsSource[itemIndex]))
{
SwipedRightCommand.Execute(ItemsSource[itemIndex]);
}
}
else
{
SwipedLeft?.Invoke(ItemsSource[itemIndex]);
if (SwipedLeftCommand != null && SwipedLeftCommand.CanExecute(ItemsSource[itemIndex]))
{
SwipedLeftCommand.Execute(ItemsSource[itemIndex]);
}
}
// Next card
itemIndex++;
ShowNextCard();
}
else
{
// Move card back to the center
var traslateAnmimation = topCard.TranslateTo((-topCard.X), -topCard.Y, animationLength, Easing.SpringOut);
var rotateAnimation = topCard.RotateTo(0, animationLength, Easing.SpringOut);
// Scale the back card down
var scaleAnimation = backCard.ScaleTo(defaultSubcardScale, animationLength, Easing.SpringOut);
// Run all animations from above simultaneiously
await Task.WhenAll(new List <Task> {
traslateAnmimation, rotateAnimation, scaleAnimation
});
}
if (itemIndex < ItemsSource.Count)
{
FinishedDragging?.Invoke(ItemsSource[itemIndex]);
}
}
async Task HandleTouchCompleted()
{
if (itemIndex >= ItemsSource.Count)
{
return;
}
var topCard = CardStack.Children[numberOfCards - 1];
var backCard = CardStack.Children[numberOfCards - 2];
// Check if card has been dragged far enough to trigger action
if (Math.Abs(cardDistance) >= CardMoveDistance)
{
// Move card off the screen
await topCard.TranslateTo(cardDistance > 0?this.Width * 2 : -this.Width * 2, 0, defaultAnimationLength, Easing.SinIn);
topCard.IsVisible = false;
// Fire events
if (cardDistance > 0)
{
Swiped?.Invoke(this, new SwipedEventArgs(ItemsSource[itemIndex], SwipeDirection.Right));
if (SwipedRightCommand != null && SwipedRightCommand.CanExecute(ItemsSource[itemIndex]))
{
SwipedRightCommand.Execute(ItemsSource[itemIndex]);
}
}
else
{
Swiped?.Invoke(this, new SwipedEventArgs(ItemsSource[itemIndex], SwipeDirection.Left));
if (SwipedLeftCommand != null && SwipedLeftCommand.CanExecute(ItemsSource[itemIndex]))
{
SwipedLeftCommand.Execute(ItemsSource[itemIndex]);
}
}
// Next card
itemIndex++;
ShowNextCard();
}
else
{
// Run animations simultaniously
await Task.WhenAll(
// Move card back to the center
topCard.TranslateTo((-topCard.X), -topCard.Y, defaultAnimationLength, Easing.SpringOut),
topCard.RotateTo(0, defaultAnimationLength, Easing.SpringOut),
// Scale the back card down
backCard.ScaleTo(defaultSubcardScale, defaultAnimationLength, Easing.SpringOut)
);
}
if (itemIndex < ItemsSource.Count)
{
FinishedDragging?.Invoke(this, new DraggingEventArgs(ItemsSource[itemIndex]));
}
}
public async void Swipe(SwipeDirection direction, uint animationLength = defaultAnimationLength)
{
// Check if there is something to swipe
if (itemIndex >= ItemsSource?.Count)
{
return;
}
var topCard = CardStack.Children[numberOfCards - 1];
var backCard = CardStack.Children[numberOfCards - 2];
// Fire events
Swiped?.Invoke(this, new SwipedEventArgs(ItemsSource[itemIndex], direction));
if (direction == SwipeDirection.Left)
{
if (SwipedLeftCommand != null && SwipedLeftCommand.CanExecute(ItemsSource[itemIndex]))
{
SwipedLeftCommand.Execute(ItemsSource[itemIndex]);
}
}
else if (direction == SwipeDirection.Right)
{
if (SwipedRightCommand != null && SwipedRightCommand.CanExecute(ItemsSource[itemIndex]))
{
SwipedRightCommand.Execute(ItemsSource[itemIndex]);
}
}
// Increase item index
// Do that before the animation runs
itemIndex++;
// Animate card
await Task.WhenAll(
// Move card left or right
topCard.TranslateTo(direction == SwipeDirection.Right ? this.Width * 2 : -this.Width * 2, 0, animationLength, Easing.SinIn),
// Rotate card (57.2957795f/3=17.18873385f)
topCard.RotateTo(direction == SwipeDirection.Right ? 17.18873385f : -17.18873385f, animationLength, Easing.SinIn),
// Scale back card up
backCard.ScaleTo(1.0f, animationLength)
);
topCard.IsVisible = false;
// Next card
ShowNextCard();
}
public async Task Swipe(SwipeDirection direction, uint animationLength = DefaultAnimationLength)
{
if (_itemIndex >= ItemsSource?.Count)
{
NoMoreCards?.Invoke(this, new EventArgs());
return;
}
var topCard = CardStack.Children[NumberOfCards - 1];
var backCard = CardStack.Children[NumberOfCards - 2];
Swiped?.Invoke(this, new SwipedEventArgs(ItemsSource[_itemIndex], direction));
if (direction == SwipeDirection.Left)
{
if (SwipedLeftCommand != null && SwipedLeftCommand.CanExecute(ItemsSource[_itemIndex]))
{
SwipedLeftCommand.Execute(ItemsSource[_itemIndex]);
}
}
else if (direction == SwipeDirection.Right)
{
if (SwipedRightCommand != null && SwipedRightCommand.CanExecute(ItemsSource[_itemIndex]))
{
SwipedRightCommand.Execute(ItemsSource[_itemIndex]);
}
}
_itemIndex++;
await Task.WhenAll(
topCard.TranslateTo(direction == SwipeDirection.Right ? Width * 2 : -Width * 2, 0, animationLength, Easing.SinIn),
topCard.RotateTo(direction == SwipeDirection.Right ? 17.18873385f : -17.18873385f, animationLength, Easing.SinIn),
backCard.ScaleTo(1.0f, animationLength),
backCard.TranslateTo(0, 0, animationLength, Easing.SinIn),
backCard.FadeTo(1, animationLength, Easing.SinIn)
);
topCard.IsVisible = false;
ShowNextCard();
}
private async Task HandleTouchCompleted()
{
if (_itemIndex >= ItemsSource.Count || !_isDragging)
{
return;
}
_lastX = 0;
_isDragging = false;
var topCard = CardStack.Children[NumberOfCards - 1];
var backCard = CardStack.Children[NumberOfCards - 2];
if (Math.Abs(_cardDistance) >= CardMoveDistance)
{
await topCard.TranslateTo(_cardDistance > 0?Width * 2 : -Width * 2, 0, DefaultAnimationLength, Easing.SinIn);
topCard.IsVisible = false;
if (_cardDistance > 0)
{
Swiped?.Invoke(this, new SwipedEventArgs(ItemsSource[_itemIndex], SwipeDirection.Right));
if (SwipedRightCommand != null && SwipedRightCommand.CanExecute(ItemsSource[_itemIndex]))
{
SwipedRightCommand.Execute(ItemsSource[_itemIndex]);
}
}
else
{
Swiped?.Invoke(this, new SwipedEventArgs(ItemsSource[_itemIndex], SwipeDirection.Left));
if (SwipedLeftCommand != null && SwipedLeftCommand.CanExecute(ItemsSource[_itemIndex]))
{
SwipedLeftCommand.Execute(ItemsSource[_itemIndex]);
}
}
_itemIndex++;
ShowNextCard();
}
else
{
await Task.WhenAll(
topCard.TranslateTo((-topCard.X), -topCard.Y, DefaultAnimationLength, Easing.SpringOut),
topCard.RotateTo(0, DefaultAnimationLength, Easing.SpringOut),
backCard.ScaleTo(_defaultSubcardScale, DefaultAnimationLength, Easing.SpringOut),
backCard.TranslateTo(_defaultSubcardTranslationX, 0, DefaultAnimationLength, Easing.SpringOut),
backCard.FadeTo(_defaultSubcardOpacity, DefaultAnimationLength, Easing.SpringOut)
);
}
_cardDistance = 0;
if (_itemIndex < ItemsSource.Count)
{
FinishedDragging?.Invoke(this, new DraggingEventArgs(ItemsSource[_itemIndex], _cardDistance));
}
}
