任何人都可以指出一些代码示例，说明我如何在 iOS 中实现一个画廊，在 Windows 7 上使用触摸屏显示器时，您可以左右滑动来更改图像？
问问题
7379 次
1 回答
4
您将需要为此实现类似滑动的动画。
我自己没有尝试过，但这里似乎是一个 WPF 轮播的开源仓库，可能值得一看
在所需的“滑动移动”上更改图像:)
希望能帮助到你！
这是（顺便说一下）第二个链接中的轮播控件，以防它像上一个一样丢失：
迈克尔帕洛塔斯的代码
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Threading;
namespace WPFDemo
{
public class CarouselControl : Canvas
{
public CarouselControl()
{
_timer.Tick += new EventHandler(TimerTick);
_timer.Interval = TimeSpan.FromMilliseconds(10);
}
public DateTime _previousTime;
public DateTime _currentTime;
public void ReInitialize()
{
Init();
}
protected override void OnInitialized(EventArgs e)
{
base.OnInitialized(e);
Init();
}
public delegate void OnElementSelectedHandler(object sender);
public event OnElementSelectedHandler OnElementSelected;
public void SelectElement(FrameworkElement element)
{
if (element != null)
{
_previousTime = DateTime.Now;
RotateToElement(element);
if (OnElementSelected != null)
OnElementSelected(element);
}
}
private const double DEFAULT_ROTATION_SPEED = 200;
private const double MINIMUM_ROTATION_SPEED = 1;
private const double MAXIMUM_ROTATION_SPEED = 1000;
private double _rotationSpeed = DEFAULT_ROTATION_SPEED;
public double RotationSpeed
{
get
{
return _rotationSpeed;
}
set
{
_rotationSpeed = Math.Min(Math.Max(value, MINIMUM_ROTATION_SPEED), MAXIMUM_ROTATION_SPEED);
}
}
private const double DEFAULT_LOOKDOWN_OFFSET = 0;
private const double MINIMUM_LOOKDOWN_OFFSET = -100;
private const double MAXIMUM_LOOKDOWN_OFFSET = 100;
private double _lookdownOffset = DEFAULT_LOOKDOWN_OFFSET;
public double LookDownOffset
{
get
{
return _lookdownOffset;
}
set
{
_lookdownOffset = Math.Min(Math.Max(value, MINIMUM_LOOKDOWN_OFFSET), MAXIMUM_LOOKDOWN_OFFSET);
}
}
private const double DEFAULT_FADE = 0.5;
private const double MINIMUM_FADE = 0;
private const double MAXIMUM_FADE = 1;
private double _fade = DEFAULT_FADE;
public double Fade
{
get
{
return _fade;
}
set
{
_fade = Math.Min(Math.Max(value, MINIMUM_FADE), MAXIMUM_FADE);
}
}
private const double DEFAULT_SCALE = 0.5;
private const double MINIMUM_SCALE = 0;
private const double MAXIMUM_SCALE = 1;
private double _scale = DEFAULT_SCALE;
public double Scale
{
get
{
return _scale;
}
set
{
_scale = Math.Min(Math.Max(value, MINIMUM_SCALE), MAXIMUM_SCALE);
}
}
private void element_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
SelectElement(sender as FrameworkElement);
}
private void RotateToElement(FrameworkElement element)
{
if (element != _currentlySelected)
{
_currentlySelected = element;
int targetIndex = Children.IndexOf(element);
double degreesToRotate = GetDegreesNeededToPlaceElementInFront(_currentRotation, targetIndex, TotalNumberOfElements);
_targetRotation = ClampDegrees(_currentRotation - degreesToRotate);
StartRotation(degreesToRotate);
}
}
internal static double GetDegreesNeededToPlaceElementInFront(double currentRotation, int targetIndex, int totalNumberOfElements)
{
double rawDegrees = -(180.0 - (currentRotation + 360.0 * ((double)targetIndex / (double)totalNumberOfElements)));
if (rawDegrees > 180)
return -(360 - rawDegrees);
return rawDegrees;
}
private double RotationAmount
{
get
{
return (_currentTime - _previousTime).TotalSeconds * _rotationSpeed;
}
}
private const double INTERNAL_SCALE_COEFFICIENT = 0.6;
private void Init()
{
_previousTime = _currentTime = DateTime.Now;
X_SCALE = CenterX * INTERNAL_SCALE_COEFFICIENT;
Y_SCALE = CenterY * INTERNAL_SCALE_COEFFICIENT;
foreach (FrameworkElement element in Children)
{
element.MouseLeftButtonDown += new MouseButtonEventHandler(element_MouseLeftButtonDown);
element.Cursor = Cursors.Hand;
}
SelectElement(GetChild(0));
SetElementPositions();
}
private FrameworkElement _currentlySelected = null;
public FrameworkElement CurrentlySelected { get { return _currentlySelected; } }
protected double CenterX { get { return this.Width / 2.0; } }
protected double CenterY { get { return this.Height / 2.0; } }
protected double X_SCALE = 0;
protected double Y_SCALE = 0;
protected DispatcherTimer _timer = new DispatcherTimer();
private double _rotationToGo = 0;
private int TotalNumberOfElements { get { return Children.Count; } }
protected double _currentRotation = 0;
protected double _targetRotation = 0;
protected virtual void TimerTick(object sender, EventArgs e)
{
_currentTime = DateTime.Now;
if ((_rotationToGo < RotationAmount) && (_rotationToGo > -RotationAmount))
{
_rotationToGo = 0;
if (_currentRotation != _targetRotation)
{
_currentRotation = _targetRotation;
}
else
{
_timer.Stop();
return;
}
}
else if (_rotationToGo < 0)
{
_rotationToGo += RotationAmount;
_currentRotation = ClampDegrees(_currentRotation + RotationAmount);
}
else
{
_rotationToGo -= RotationAmount;
_currentRotation = ClampDegrees(_currentRotation - RotationAmount);
}
SetElementPositions();
_previousTime = _currentTime;
}
protected double ClampDegrees(double rawDegrees)
{
if (rawDegrees > 360)
return rawDegrees - 360;
if (rawDegrees < 0)
return rawDegrees + 360;
return rawDegrees;
}
public void SetElementPositions()
{
for (int index = 0; index < TotalNumberOfElements; index++)
{
FrameworkElement element = GetChild(index);
double elementWidthCenter = GetElementCenter(element.Width, element.ActualWidth);
double elementHeightCenter = GetElementCenter(element.Height, element.ActualHeight);
double degrees = 360 * ((double)index / (double)TotalNumberOfElements) + _currentRotation;
double x = -X_SCALE * Math.Sin(ConvertToRads(degrees)) - (double.IsNaN(Y_SCALE) ? 0.0 : Y_SCALE / 100.0) * (Math.Cos(ConvertToRads(degrees)) * LookDownOffset);
Canvas.SetLeft(element, x + CenterX - elementWidthCenter);
double y = Y_SCALE * Math.Sin(ConvertToRads(degrees)) - (double.IsNaN(X_SCALE) ? 0.0 : X_SCALE / 100.0) * (Math.Cos(ConvertToRads(degrees)) * LookDownOffset);
Canvas.SetTop(element, y + CenterY - elementHeightCenter);
ScaleTransform scale = element.RenderTransform as ScaleTransform;
if (scale == null)
{
scale = new ScaleTransform();
element.RenderTransform = scale;
}
scale.CenterX = elementWidthCenter;
scale.CenterY = elementHeightCenter;
scale.ScaleX = scale.ScaleY = GetScaledSize(degrees);
Canvas.SetZIndex(element, GetZValue(degrees));
SetOpacity(element, degrees);
}
}
private FrameworkElement GetChild(int index)
{
if (Children.Count == 0)
return null;
FrameworkElement element = Children[index] as FrameworkElement;
if (element == null)
throw new NotSupportedException("Carousel only supports children that are Framework elements");
return element;
}
internal static double GetElementCenter(double elementDimension, double elementActualDimension)
{
return double.IsNaN(elementDimension) ? elementActualDimension / 2.0 : elementDimension / 2.0;
}
private void SetOpacity(FrameworkElement element, double degrees)
{
element.Opacity = (1.0 - Fade) + Fade * GetCoefficient(degrees);
}
private int GetZValue(double degrees)
{
return (int)(360 * GetCoefficient(degrees));
}
private double GetScaledSize(double degrees)
{
return (1.0 - Scale) + Scale * GetCoefficient(degrees);
}
private double GetCoefficient(double degrees)
{
return 1.0 - Math.Cos(ConvertToRads(degrees)) / 2 - 0.5;
}
private double ConvertToRads(double degrees)
{
return degrees * Math.PI / 180.0;
}
private void StartRotation(double numberOfDegrees)
{
_rotationToGo = numberOfDegrees;
if (!_timer.IsEnabled)
{
_timer.Start();
}
}
}
}
XAML：
<UserControl
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Class="WPFDemo.SphereControl"
x:Name="UserControl"
d:DesignWidth="50" d:DesignHeight="50">
<UserControl.Resources>
<Storyboard x:Key="MouseOver">
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="LayoutRoot" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
<SplineDoubleKeyFrame KeyTime="00:00:00" Value="1"/>
<SplineDoubleKeyFrame KeyTime="00:00:00.1000000" Value="1.3" KeySpline="0,0,0.5,1"/>
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="LayoutRoot" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
<SplineDoubleKeyFrame KeyTime="00:00:00" Value="1"/>
<SplineDoubleKeyFrame KeyTime="00:00:00.1000000" Value="1.3" KeySpline="0,0,0.5,1"/>
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="Ellipse" Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[2].(GradientStop.Offset)">
<SplineDoubleKeyFrame KeyTime="00:00:00" Value="0"/>
<SplineDoubleKeyFrame KeyTime="00:00:00.1000000" Value="0.231"/>
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="Ellipse" Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[1].(GradientStop.Offset)">
<SplineDoubleKeyFrame KeyTime="00:00:00" Value="0.312"/>
<SplineDoubleKeyFrame KeyTime="00:00:00.1000000" Value="0.729"/>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
<Storyboard x:Key="MouseLeave">
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="LayoutRoot" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
<SplineDoubleKeyFrame KeyTime="00:00:00.5" Value="1" KeySpline="0,0,0.5,1"/>
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="LayoutRoot" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
<SplineDoubleKeyFrame KeyTime="00:00:00.5" Value="1" KeySpline="0,0,0.5,1"/>
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="Ellipse" Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[2].(GradientStop.Offset)">
<SplineDoubleKeyFrame KeyTime="00:00:00.5" Value="0"/>
</DoubleAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetName="Ellipse" Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[1].(GradientStop.Offset)">
<SplineDoubleKeyFrame KeyTime="00:00:00.5" Value="0.312"/>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</UserControl.Resources>
<UserControl.Triggers>
<EventTrigger RoutedEvent="Mouse.MouseEnter">
<BeginStoryboard Storyboard="{StaticResource MouseOver}" x:Name="MouseOver_BeginStoryboard"/>
</EventTrigger>
<EventTrigger RoutedEvent="Mouse.MouseLeave">
<BeginStoryboard Storyboard="{StaticResource MouseLeave}" x:Name="MouseLeave_BeginStoryboard"/>
</EventTrigger>
</UserControl.Triggers>
<Grid x:Name="LayoutRoot" RenderTransformOrigin="0.5,0.5">
<Grid.RenderTransform>
<TransformGroup>
<ScaleTransform ScaleX="1" ScaleY="1"/>
<SkewTransform AngleX="0" AngleY="0"/>
<RotateTransform Angle="0"/>
<TranslateTransform X="0" Y="0"/>
</TransformGroup>
</Grid.RenderTransform>
<Ellipse Name="Ellipse" >
<Ellipse.Fill>
<RadialGradientBrush GradientOrigin="0.258,0.21">
<GradientStop x:Name="OuterColor" Offset="0.9"/>
<GradientStop x:Name="InnerColor" Offset="0.312"/>
<GradientStop Color="#FFFFFFFF" Offset="0"/>
</RadialGradientBrush>
</Ellipse.Fill>
</Ellipse>
</Grid>
于 2012-07-10T11:17:00.963 回答