silverlight NaN 高度和宽度，ActualHeight 和 ActualWidth 也返回 0.0 - 解决方法是什么？
下面的 popUpControl 和 listBoxControl 返回 NaN 作为高度和宽度。 ActualHeight 也是 0.0
为什么？更重要的是，解决方法是什么？
<Popup Name="popUpControl" IsOpen="True" VerticalAlignment="Top" HorizontalAlignment="Left" >
<ListBox Name="listBoxControl" SelectionChanged="_ListBox_SelectionChanged"
Style="{StaticResource ListBoxStyle}" BorderBrush="Transparent"
MaxHeight="300" MaxWidth="350" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" >
<TextBlock Text="{Binding ID}" VerticalAlignment="Center" Margin="2,0,0,0" />
<TextBlock Text="{Binding Name}" VerticalAlignment="Center" Margin="2,0,0,0" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Popup>
popUpControl and listBoxControl below are returning NaN as the height and width. The ActualHeight is also 0.0
Why? and more importantly what is the workaround for this?
<Popup Name="popUpControl" IsOpen="True" VerticalAlignment="Top" HorizontalAlignment="Left" >
<ListBox Name="listBoxControl" SelectionChanged="_ListBox_SelectionChanged"
Style="{StaticResource ListBoxStyle}" BorderBrush="Transparent"
MaxHeight="300" MaxWidth="350" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" >
<TextBlock Text="{Binding ID}" VerticalAlignment="Center" Margin="2,0,0,0" />
<TextBlock Text="{Binding Name}" VerticalAlignment="Center" Margin="2,0,0,0" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Popup>
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要更新 FrameworkElement 的
ActualWidth和ActualHeight，您必须调用UpdateLayout。希望这对某人有帮助。
To update the
ActualWidthandActualHeightof a FrameworkElement you will have to callUpdateLayout.hope this helps someone.
在 WPF 和 silverlight 中，NaN 的宽度和/或高度表示“自动”，您可能应该查看（并绑定到）的内容是 ActualWidth 和/或 ActualHeight
in WPF and silverlight, a width and/or height of NaN means "Auto" what you should probably be looking at (and binding to) instead is ActualWidth and/or ActualHeight