Logo
programming4us
programming4us
programming4us
programming4us
Home
programming4us
XP
programming4us
Windows Vista
programming4us
Windows 7
programming4us
Windows Azure
programming4us
Windows Server
programming4us
Windows Phone
 
Windows Phone

Animations : Animations and Property Precedence

- Windows 10 Product Activation Keys Free 2019 (All Versions)
- How To Bypass Torrent Connection Blocking By Your ISP
- How To Install Actual Facebook App On Kindle Fire
4/9/2011 5:13:26 PM
The sample code for this article includes a little program called ButtonSetAndAnimate that doesn’t do anything particularly useful except to illustrate how animation fits into dependency property precedence.

The XAML file contains a Slider with a range of 0 to 100, a TextBlock showing the Slider value, and four buttons:

Example 1. Silverlight Project: ButtonSetAndAnimate File: MainPage.xaml (excerpt)
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>

<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>

<TextBlock Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2"
Text="{Binding ElementName=slider, Path=Value}"
HorizontalAlignment="Center"
Margin="24" />

<Slider Name="slider"
Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2"
Minimum="0" Maximum="100"
Orientation="Horizontal"
VerticalAlignment="Center" />

<Button Grid.Row="2" Grid.Column="0"
Content="Set to 0"
Click="OnSetToZeroClick" />

<Button Grid.Row="2" Grid.Column="1"
Content="Set to 100"
Click="OnSetToOneHundredClick" />

<Button Grid.Row="3" Grid.Column="0" Grid.ColumnSpan="2"
Content="Animate to 50"
HorizontalAlignment="Center"
Click="OnAnimateTo50Click" />

<Button Grid.Row="4" Grid.Column="0" Grid.ColumnSpan="2"
Content="Set Maximum to 25"
HorizontalAlignment="Center"
Click="OnSetMaxTo40Click" />
</Grid>


Also in the XAML file is an animation that targets the Value property of the Slider.

Example 2. Silverlight Project: ButtonSetAndAnimate File: MainPage.xaml (excerpt)
<phone:PhoneApplicationPage.Resources>
<Storyboard x:Name="storyboard">
<DoubleAnimation Storyboard.TargetName="slider"
Storyboard.TargetProperty="Value"
To="50" Duration="0:0:5" />
</Storyboard>
</phone:PhoneApplicationPage.Resources>

Handlers for the four buttons are in the code-behind file:

Example 3. Silverlight Project: ButtonSetAndAnimate File: MainPage.xaml.cs (excerpt)
public partial class MainPage : PhoneApplicationPage
{
public MainPage()
{
InitializeComponent();
}

void OnSetToZeroClick(object sender, RoutedEventArgs args)
{
slider.Value = 0;
}

void OnSetToOneHundredClick(object sender, RoutedEventArgs args)
{
slider.Value = 100;
}

void OnAnimateTo50Click(object sender, RoutedEventArgs args)
{
storyboard.Begin();
}

void OnSetMaxTo40Click(object sender, RoutedEventArgs e)
{
slider.Maximum = 25;
}
}


Here’s the program:



You can manipulate the Slider with your finger and you can also use the topmost two buttons to set the Slider value to its minimum or maximum. So far, so good. Now click the “Animate to 50” button.

As the Slider is animated and moving to the center position, try overriding that movement with your finger or by pressing the “Set to 0” or “Set to 100” buttons. You can’t do it. The animation has precedence over local settings, which means that the chart of dependency property precedencemust be supplemented by putting animations at the very top:

Animations have precedence over

Local Settings which have precedence over

Style Settings, which have precedence over the

Theme Style, which has precedence over

Property Inheritance, which has precedence over

Default Values

This is as it should be. Animations must have precedence over local settings or they wouldn’t work on properties that are simply initialized to some value.

After the animation has concluded, you’ll discover that you can now manipulate the Slider both manually and with the first two buttons. This behavior is not correct and not in accordance with documentation. With the default FillBehavior setting of HoldEnd, the Slider should actually be frozen after the animation has concluded. The Slider should continue to reflect the final value of the animation.

Is there something more powerful than animations? Yes there is, but it’s probably not something you’d immediately consider, and you probably won’t find any examples outside the realm of Slider and ScrollBar.

Set the Slider to its maximum value, and press the “Animate to 50” button again. As the Slider is approaching 50, click the “Set Maximum to 25” button. That sets the Maximum property of the Slider to 25 and immediately halts the animation. And once again, it seems logical. No matter what an animation does, it makes no sense whatsoever for a Slider to have a Value that is outside the range of Minimum and Maximum. This is an example of property coercion:

Property Coercion has precedence over

Animations which have precedence over

Local Settings which have precedence over

Style Settings, which have precedence over the

Theme Style, which has precedence over

Property Inheritance, which has precedence over

Default Values

In theory, values of templated properties also fit into this chart between local settings and style settings, but these are hard to differentiate, so this is the final version of this chart in this book.

Other -----------------
- Animations : Animating Perspective Transforms
- Animations : The Easing Functions
- Animations : The Bouncing Ball Problem
- Animations : Splines and Key Frames
- Animations : Animating Attached Properties (or Not)
- Animations : Trigger on Loaded
- Animations : Key Frame Animations
- Animations : A Cautionary Tale
- Animations - XAML-Based Animations
- Animations - Some Variations
 
 
Top 10
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Finding containers and lists in Visio (part 2) - Wireframes,Legends
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Finding containers and lists in Visio (part 1) - Swimlanes
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Formatting and sizing lists
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Adding shapes to lists
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Sizing containers
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 3) - The Other Properties of a Control
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 2) - The Data Properties of a Control
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 1) - The Format Properties of a Control
- Microsoft Access 2010 : Form Properties and Why Should You Use Them - Working with the Properties Window
- Microsoft Visio 2013 : Using the Organization Chart Wizard with new data
Popular tags
Microsoft Access Microsoft Excel Microsoft OneNote Microsoft PowerPoint Microsoft Project Microsoft Visio Microsoft Word Active Directory Biztalk Exchange Server Microsoft LynC Server Microsoft Dynamic Sharepoint Sql Server Windows Server 2008 Windows Server 2012 Windows 7 Windows 8 windows Phone 7 windows Phone 8
programming4us programming4us
Celebrity Style, Fashion Trends, Beauty and Makeup Tips.
 
programming4us
Windows Vista
programming4us
Windows 7
programming4us
Windows Azure
programming4us
Windows Server