在WPF中加载XAML后访问UIElement

本文关键字：访问 UIElement XAML 加载 WPF | 更新日期: 2023-09-27 17:57:44

我有一个Canvas，它是使用从文件的XAML加载中填充的

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);

边界包含许多子元素，包括一些用户控件。

XAML文件的部分片段：

 <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="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>

当我想访问代码背后的控件时，我实际上无法使用重新挂钩到元素

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

UI元素在屏幕上显示得很好，但我总是收到一条"找不到Vis"的消息。到目前为止，从我读到的所有内容来看，只要我的元素是画布中某个地方的子元素，就应该使用FindName，对吧？我错过了什么？

感谢

在WPF中加载XAML后访问UIElement

FindName通常用于从模板中获取元素。在您的情况下，您可能最好使用LogicalTreeHelper

LogicalTreeHelper.FindLogicalNode(SBWindowContainerCanvas,
                                   "Vis3DigitScoreControl");

尝试使用该方法：

 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;
                }
            }
        }
    }

它应该将您需要的所有对象返回给您。然后你就可以在foreach循环中选择一个了。

尝试使用x:Name而不是Name，并在加载该元素后进行检查。

LogicalTreeHelper.FindLogicalNode（…）在这里工作，因为它穿过NameScope边界。

而CCD_ 5在相同的CCD_。

动态添加控件需要对NameScopes有很好的理解。

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