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Accessing UIElement after XAML Load in WPF

I have a Canvas being populated from a XAML load from a file using:

SBWindowContainerCanvas.Children.Clear();          
StreamReader stringreader = new StreamReader("C:\\xaml\\xmltest.xaml");
XmlReader xmlreader = XmlReader.Create(stringreader);

var mainborder = XamlReader.Load(xmlreader);                     
SBWindowContainerCanvas.Children.Add((Blacklight.Controls.ClippingBorder)mainborder);

The border contains many child elements including some user controls.

partial snippet of XAML file:

 <av:ContentControl Name="VisScoreCC" Width="417" Height="228" IsHitTestVisible="True" av:Canvas.Left="855" av:Canvas.Top="8" av:Selector.IsSelected="False">
  <fsp:Scores3DigitControl Name="Vis3DigitScoreControl" VisitorControl="True" OperatorControl="True" NumericValue="4" UseGradientMainBG="False" UseGradientNumberBG="False" UseGradientLogoBG="False" UseGradientTeamNameBG="False" UseRadialMainBG="False" UseRadialNumberBG="False" UseRadialLogoBG="False" UseRadialTeamNameBG="False" UseImageStringMainBG="False|none|False|Tile|Top Left|1" SolidColorMainBG="#FFD4D2D2" SolidColorNumberBG="#FF000000" SolidColorBannerBG="#FF000000" FGColorNumbers="#FFFF0000" FGColorTeamName="#FFFFFFFF" FGColorBanner="#FFFFA500" SolidColorImageLogoBG="#FF000000" SolidColorTeamNameBG="#FF000000" GradientMainBG="#FF000000|#FF808080|#FFFFFFFF" GradientNumberBG="#FF000000|#FF808080|#FFFFFFFF" GradientLogoBG="#FF000000|#FF808080|#FFFFFFFF" GradientTeamNameBG="#FF000000|#FF808080|#FFFFFFFF" GradientOffsetsMainBG="0|0.5|1" GradientOffsetsNumbersBG="0|0.5|1" GradientOffsetsLogoBG="0|0.5|1" GradientOffsetsTeamNameBG="0|0.5|1" LinearAngleMainBG="180" LinearAngleNumberBG="180" LinearAngleLogoBG="180" LinearAngleTeamNameBG="180" OffSegmentOpacity="0.1" RoundRadiusNumbers="0" RoundRadiusLogo="0" RoundRadiusTeamName="0" PosSizeStringNumbers="180|8|200|150" PosSizeStringLogo="20|10|150|150" PosSizeStringTeamName="25|165|360|60" TeamNameFontString="Arial|40|True" UseRightSideBanner="True" Style="{av:DynamicResource Scores3DigitControlTemplate}" Height="Auto" Margin="0,0,0,0" IsHitTestVisible="True" />
</av:ContentControl>
<av:ContentControl Name="HomeScoreCC" Width="417" Height="228" IsHitTestVisible="True" av:Canvas.Left="11" av:Canvas.Top="8" av:Selector.IsSelected开发者_如何学Python="False">
  <fsp:Scores3DigitControl Name="Home3DigitScoreControl" VisitorControl="False" OperatorControl="True" NumericValue="4" UseGradientMainBG="False" UseGradientNumberBG="False" UseGradientLogoBG="False" UseGradientTeamNameBG="False" UseRadialMainBG="False" UseRadialNumberBG="False" UseRadialLogoBG="False" UseRadialTeamNameBG="False" UseImageStringMainBG="False|none|False|Tile|Top Left|1" TargetElementIndex="0" SolidColorMainBG="#FFD4D2D2" SolidColorNumberBG="#FF000000" SolidColorBannerBG="#FF000000" FGColorNumbers="#FFFF0000" FGColorTeamName="#FFFFFFFF" FGColorBanner="#FFFFA500" SolidColorImageLogoBG="#FF000000" SolidColorTeamNameBG="#FF000000" GradientMainBG="#FF000000|#FF808080|#FFFFFFFF" GradientNumberBG="#FF000000|#FF808080|#FFFFFFFF" GradientLogoBG="#FF000000|#FF808080|#FFFFFFFF" GradientTeamNameBG="#FF000000|#FF808080|#FFFFFFFF" GradientOffsetsMainBG="0|0.5|1" GradientOffsetsNumbersBG="0|0.5|1" GradientOffsetsLogoBG="0|0.5|1" GradientOffsetsTeamNameBG="0|0.5|1" LinearAngleMainBG="180" LinearAngleNumberBG="180" LinearAngleLogoBG="180" LinearAngleTeamNameBG="180" OffSegmentOpacity="0.1" RoundRadiusNumbers="0" RoundRadiusLogo="0" RoundRadiusTeamName="0" PosSizeStringNumbers="35|8|200|150" PosSizeStringLogo="250|10|150|150" PosSizeStringTeamName="25|165|360|60" TeamNameFontString="Arial|40|True" UseRightSideBanner="False" Style="{av:DynamicResource Scores3DigitControlTemplate}" OverridesDefaultStyle="False" Name="Home3DigitScoreControl" Height="Auto" IsHitTestVisible="True" />
</av:ContentControl>

When I want to get access to my controls in code-behind, I am not able to actually re-hook to the elements using:

Scores3DigitControl Vis3DigitScoreControlC = (Scores3DigitControl)SBWindowContainerCanvas.FindName("Vis3DigitScoreControl");
if (Vis3DigitScoreControlC == null)
{
    MessageBox.Show("Couldn't Find Vis");
}
else
{
    Vis3DigitScoreControlC.Visibility = Visibility.Hidden;
}

The UI Elements show up fine on the screen but I always get a "Couldn't Find Vis" message. From everything I read so far, using the FindName should work as long as my element is a child somewhere in the canvas, right? What am I missing?

Thank you


FindName is generally used for getting elements from a template. In your case your probably best to use the LogicalTreeHelper

LogicalTreeHelper.FindLogicalNode(SBWindowContainerCanvas,
                                   "Vis3DigitScoreControl");


Try to use that method:

 public IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject
    {
        if (depObj != null)
        {
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
            {
                DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
                if (child != null && child is T)
                {
                    yield return (T)child;
                }

                foreach (T childOfChild in FindVisualChildren<T>(child))
                {
                    yield return childOfChild;
                }
            }
        }
    }

It should return to you all object which you need. And after you will be able choose one in foreach loop.


Try using x:Name instead of Name and checking after that element has loaded.


LogicalTreeHelper.FindLogicalNode(...) works here, because it goes across NameScope boundries.

Whereas FindName(...) works in same NameScope.

Dynamically adding controls require good understanding of NameScopes.

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