using?System;
using?System.Linq;
using?System.Windows;
using?System.Windows.Controls;
using?System.Windows.Input;
using?System.Windows.Media;
using?System.Windows.Media.Animation;
using?System.Windows.Media.Effects;

namespace?WPFDevelopers.Controls
{
????public?enum?CountdownTimerEffect
????{
????????Default,
????????MultiColor
????}
????public?class?CountdownTimer?:?ContentControl
????{
????????private?Storyboard?storyboard;
????????private?const?double?seconds?=?800;
????????private?double?currentSeconds?=?seconds;
????????private?Grid?myGrid;
????????public?int?Number
????????{
????????????get?{?return?(int)GetValue(NumberProperty);?}
????????????set?{?SetValue(NumberProperty,?value);?}
????????}

????????public?static?readonly?DependencyProperty?NumberProperty?=
????????DependencyProperty.Register("Number",?typeof(int),?typeof(CountdownTimer),?new?PropertyMetadata(3));


????????///?<summary>
????????///?完成后回到開始
????????///?</summary>
????????public?bool?IsFinishStart
????????{
????????????get?{?return?(bool)GetValue(IsFinishStartProperty);?}
????????????set?{?SetValue(IsFinishStartProperty,?value);?}
????????}

????????public?static?readonly?DependencyProperty?IsFinishStartProperty?=
????????????DependencyProperty.Register("IsFinishStart",?typeof(bool),?typeof(CountdownTimer),?new?PropertyMetadata(false));



????????public?CountdownTimerEffect?CountdownTimerEffect
????????{
????????????get?{?return?(CountdownTimerEffect)GetValue(CountdownTimerEffectProperty);?}
????????????set?{?SetValue(CountdownTimerEffectProperty,?value);?}
????????}

????????public?static?readonly?DependencyProperty?CountdownTimerEffectProperty?=
????????????DependencyProperty.Register("ExhibitionEnum",?typeof(CountdownTimerEffect),?typeof(CountdownTimer),?new?PropertyMetadata(CountdownTimerEffect.Default));



????????public?override?void?OnApplyTemplate()
????????{
????????????base.OnApplyTemplate();
????????????NameScope.SetNameScope(this,?new?NameScope());
????????????if?(FontSize?==?SystemFonts.CaptionFontSize)
????????????????FontSize?=?200;
????????????FontFamily?=?DrawingContextHelper.FontFamily;
????????????storyboard?=?new?Storyboard();
????????????myGrid?=?new?Grid();
????????????myGrid.Name?=?"myGrid";
????????????myGrid.ToolTip?=?"MouseDown";
????????????myGrid.Background?=?new?SolidColorBrush(Colors.White);
????????????var?linearGradient?=?new?LinearGradientBrush
????????????{
????????????????GradientStops?=?new?GradientStopCollection
????????????????{
???????????????????new?GradientStop{?Color?=?Colors.Red,?Offset?=?1?},
???????????????????new?GradientStop{?Color?=?Colors.White,?Offset?=?1?},
???????????????????new?GradientStop{?Color?=?Colors.White,?Offset?=?.5?},
???????????????????new?GradientStop{?Color?=?Colors.Red,?Offset?=?.5?},
???????????????????new?GradientStop{?Color?=?Colors.Red,?Offset?=?0?},
???????????????????new?GradientStop{?Color?=?Colors.White,?Offset?=?0?},
????????????????},
????????????????StartPoint?=?new?Point(0.5,?0),
????????????????EndPoint?=?new?Point(10,?10),
????????????????SpreadMethod?=?GradientSpreadMethod.Reflect,
????????????????MappingMode?=?BrushMappingMode.Absolute
????????????};
????????????SolidColorBrush?solidColor;
????????????this.RegisterName(myGrid.Name,?myGrid);
????????????var?num?=?0;
????????????for?(int?i?=?Number;?i?>=?num;?i--)
????????????{
????????????????var?textBlock?=?new?TextBlock();
????????????????switch?(CountdownTimerEffect)
????????????????{
????????????????????case?CountdownTimerEffect.Default:
????????????????????????if?(i?%?2?==?0)
????????????????????????????solidColor?=?Brushes.White;
????????????????????????else
????????????????????????????solidColor?=?Brushes.Black;
????????????????????????textBlock.Foreground?=?solidColor;
????????????????????????break;
????????????????????case?CountdownTimerEffect.MultiColor:
????????????????????????textBlock.Foreground?=?linearGradient;
????????????????????????break;

????????????????}

????????????????textBlock.Text?=?i.ToString();
????????????????textBlock.Name?=?$"textBlock{i}";
????????????????textBlock.FontSize?=?FontSize;
????????????????textBlock.FontWeight?=?FontWeights.ExtraBold;
????????????????textBlock.VerticalAlignment?=?VerticalAlignment.Center;
????????????????textBlock.HorizontalAlignment?=?HorizontalAlignment.Center;
????????????????textBlock.RenderTransformOrigin?=?new?Point(.5,?.5);
????????????????textBlock.Effect?=?new?DropShadowEffect
????????????????{
????????????????????ShadowDepth?=?2,
????????????????????RenderingBias?=?RenderingBias.Performance,
????????????????????Color?=?Colors.Red
????????????????};
????????????????if?(!i.Equals(Number))
????????????????????textBlock.Opacity?=?0;
????????????????textBlock.RenderTransform?=?new?ScaleTransform
????????????????{
????????????????????ScaleX?=?2,
????????????????????ScaleY?=?2,
????????????????};
????????????????this.RegisterName(textBlock.Name,?textBlock);

????????????????TimeSpan?beginTime?=?TimeSpan.Zero;
????????????????if?(storyboard.Children.Count?>?0)
????????????????{
????????????????????beginTime?=?TimeSpan.FromMilliseconds(currentSeconds);
????????????????????currentSeconds?+=?seconds;
????????????????}
????????????????var?cubicEase?=?new?CubicEase
????????????????{
????????????????????EasingMode?=?EasingMode.EaseIn,
????????????????};
????????????????DoubleAnimation?doubleAnimationScaleX?=?new?DoubleAnimation();
????????????????doubleAnimationScaleX.From?=?2;
????????????????doubleAnimationScaleX.To?=?0;
????????????????doubleAnimationScaleX.EasingFunction?=?cubicEase;


????????????????Storyboard.SetTargetName(doubleAnimationScaleX,?textBlock.Name);
????????????????Storyboard.SetTargetProperty(doubleAnimationScaleX,?new?PropertyPath("(TextBlock.RenderTransform).(ScaleTransform.ScaleX)"));

????????????????var?doubleAnimationScaleY?=?new?DoubleAnimation
????????????????{
????????????????????From?=?2,
????????????????????To?=?0,
????????????????????EasingFunction?=?cubicEase
????????????????};
????????????????Storyboard.SetTargetName(doubleAnimationScaleY,?textBlock.Name);
????????????????Storyboard.SetTargetProperty(doubleAnimationScaleY,?new?PropertyPath("(TextBlock.RenderTransform).(ScaleTransform.ScaleY)"));




????????????????doubleAnimationScaleX.BeginTime?=?beginTime;
????????????????doubleAnimationScaleY.BeginTime?=?beginTime;
????????????????doubleAnimationScaleX.Duration?=?TimeSpan.FromMilliseconds(seconds);
????????????????doubleAnimationScaleY.Duration?=?TimeSpan.FromMilliseconds(seconds);
????????????????if?(!i.Equals(Number))
????????????????{
????????????????????var?doubleAnimationOpacity?=?new?DoubleAnimation
????????????????????{
????????????????????????Duration?=?TimeSpan.FromMilliseconds(0),
????????????????????????BeginTime?=?beginTime,
????????????????????????From?=?0,
????????????????????????To?=?1
????????????????????};
????????????????????Storyboard.SetTargetName(doubleAnimationOpacity,?textBlock.Name);
????????????????????Storyboard.SetTargetProperty(doubleAnimationOpacity,?new?PropertyPath(TextBlock.OpacityProperty));
????????????????????storyboard.Children.Add(doubleAnimationOpacity);
????????????????}


????????????????if?(i?%?2?==?0)
????????????????{
????????????????????var?colorAnimation?=?new?ColorAnimation
????????????????????{
????????????????????????Duration?=?TimeSpan.FromMilliseconds(0),
????????????????????????From?=?Colors.White,
????????????????????????BeginTime?=?beginTime,
????????????????????????To?=?Colors.Black
????????????????????};
????????????????????Storyboard.SetTargetName(colorAnimation,?myGrid.Name);
????????????????????Storyboard.SetTargetProperty(colorAnimation,?new?PropertyPath("(Panel.Background).(SolidColorBrush.Color)"));
????????????????????storyboard.Children.Add(colorAnimation);
????????????????}
????????????????else
????????????????{
????????????????????if?(!i.Equals(Number))
????????????????????{
????????????????????????var?colorAnimation?=?new?ColorAnimation
????????????????????????{
????????????????????????????Duration?=?TimeSpan.FromMilliseconds(0),
????????????????????????????BeginTime?=?beginTime,
????????????????????????????From?=?Colors.Black,
????????????????????????????To?=?Colors.White
????????????????????????};
????????????????????????Storyboard.SetTargetName(colorAnimation,?myGrid.Name);
????????????????????????Storyboard.SetTargetProperty(colorAnimation,?new?PropertyPath("(Panel.Background).(SolidColorBrush.Color)"));
????????????????????????storyboard.Children.Add(colorAnimation);
????????????????????}
????????????????}


????????????????storyboard.Children.Add(doubleAnimationScaleX);
????????????????storyboard.Children.Add(doubleAnimationScaleY);


????????????????myGrid.Children.Add(textBlock);
????????????}
????????????this.Content?=?myGrid;

????????}

????????protected?override?void?OnMouseDown(MouseButtonEventArgs?e)
????????{
????????????base.OnMouseDown(e);

????????????if?(storyboard?!=?null?&&?storyboard.Children.Count?>?0)
????????????{
????????????????storyboard.Completed?+=?(s,?y)?=>
????????????????{
????????????????????myGrid.Background?=?new?SolidColorBrush(Colors.White);
????????????????????if?(IsFinishStart)
????????????????????{
????????????????????????var?scaleTransform?=?new?ScaleTransform
????????????????????????{
????????????????????????????ScaleX?=?2,
????????????????????????????ScaleY?=?2
????????????????????????};
????????????????????????var?tb?=?myGrid.Children.Cast<TextBlock>().First();
????????????????????????tb.RenderTransform?=?scaleTransform;
????????????????????}
????????????????};
????????????????storyboard.Begin(this);

????????????}

????????}
????}
}

二、CountdownTimerExample.xaml 代碼如下

<UserControl?x:Class="WPFDevelopers.Samples.ExampleViews.CountdownTimerExample"
?????????????xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
?????????????xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
?????????????xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"?
?????????????xmlns:d="http://schemas.microsoft.com/expression/blend/2008"?
?????????????xmlns:local="clr-namespace:WPFDevelopers.Samples.ExampleViews"
?????????????xmlns:wpfdev="https://github.com/yanjinhuagood/WPFDevelopers"
?????????????mc:Ignorable="d"?
?????????????d:DesignHeight="450"?d:DesignWidth="800">
???
????<Grid?Margin="10"?Grid.Row="1">
????????<Grid.RowDefinitions>
????????????<RowDefinition?Height="Auto"/>
????????????<RowDefinition?Height="*"/>
????????</Grid.RowDefinitions>
????????<Border?Margin="0,0,0,0"?Background="{StaticResource?WhiteSolidColorBrush}"?CornerRadius="4,4,0,0"?
????????????????????Effect="{StaticResource?NormalShadowDepth}">
????????????<wpfdev:NavigateMenu?TabStripPlacement="Top"?SelectionChanged="NavigateMenu_SelectionChanged">
????????????????<ListBoxItem?Content="Default"/>
????????????????<ListBoxItem?Content="MultiColor"/>
????????????</wpfdev:NavigateMenu>
????????</Border>
????????<Border?Grid.Row="1"?Background="{StaticResource?WhiteSolidColorBrush}"?CornerRadius="0,0,4,4"
????????????????????Effect="{StaticResource?NormalShadowDepth}">
????????????<Grid?Margin="10">
????????????????<wpfdev:CountdownTimer?Number="3"?x:Name="CountdownTimer1"/>
????????????????<UniformGrid?Columns="4"?Visibility="Collapsed"?x:Name="CountdownTimerGroup">
????????????????????<wpfdev:CountdownTimer?Number="9"?CountdownTimerEffect="MultiColor"?FontSize="150"?IsFinishStart="True"/>
????????????????????<wpfdev:CountdownTimer?Number="5"?CountdownTimerEffect="MultiColor"?FontSize="150"?IsFinishStart="True"/>
????????????????????<wpfdev:CountdownTimer?Number="2"?CountdownTimerEffect="MultiColor"?FontSize="150"?IsFinishStart="True"/>
????????????????????<wpfdev:CountdownTimer?Number="7"?CountdownTimerEffect="MultiColor"?FontSize="150"?IsFinishStart="True"/>
????????????????</UniformGrid>
????????????</Grid>
????????</Border>
????</Grid>
</UserControl>

三、CountdownTimerExample.xaml.cs 代碼如下

using?System.Windows;
using?System.Windows.Controls;

namespace?WPFDevelopers.Samples.ExampleViews
{
????///?<summary>
????///?CountdownTimerExample.xaml?的交互邏輯
????///?</summary>
????public?partial?class?CountdownTimerExample?:?UserControl
????{
????????public?CountdownTimerExample()
????????{
????????????InitializeComponent();
????????}

????????private?void?NavigateMenu_SelectionChanged(object?sender,?SelectionChangedEventArgs?e)
????????{
????????????var?item?=?e.AddedItems[0]?as?ListBoxItem;
????????????if?(item?==?null)?return;
????????????switch?(item.Content.ToString())
????????????{
????????????????case?"Default":
????????????????????if(CountdownTimer1.Visibility?!=?Visibility.Visible)
????????????????????{
????????????????????????CountdownTimer1.Visibility?=?Visibility.Visible;
????????????????????????CountdownTimerGroup.Visibility?=?Visibility.Collapsed;
????????????????????}
????????????????????break;
????????????????case?"MultiColor":
????????????????????if?(CountdownTimerGroup.Visibility?!=?Visibility.Visible)
????????????????????{
????????????????????????CountdownTimerGroup.Visibility?=?Visibility.Visible;
????????????????????????CountdownTimer1.Visibility?=?Visibility.Collapsed;
????????????????????}
????????????????????break;
????????????}
????????}
????}
}

效果預覽