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WPF:DockPanel最后一个可见子填充?

dockpanel grid-layout grid xaml wpf

Derrick Moeller · 技术社区 · 10 年前

我所寻找的行为基本上是DockPanel的行为,我希望最后一个孩子能填满可用空间。关键是我希望它是最后一个可见的孩子。在我的例子中,我想并排显示两个视图。

到目前为止,我已经尝试将两种不同的样式应用于网格,但似乎都不起作用。我也尝试过使用一个理论上似乎有效的转换器(我能够使用double.NaN返回“Auto”),但我不确定如何从代码中返回宽度为“*”的值。

<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*">
            <ColumnDefinition.Style>
                <Style TargetType="{x:Type ColumnDefinition}">
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding Visibility, ElementName=ccSomeItems}" Value="Collapsed">
                            <Setter Property="Width" Value="0" />
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </ColumnDefinition.Style>
        </ColumnDefinition>
        <ColumnDefinition Width="*">
            <ColumnDefinition.Style>
                <Style TargetType="{x:Type ColumnDefinition}">
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding SomeOtherItems.AllOtherItems.Count, Converter={StaticResource IntegerToVisibilityConverter}}" Value="Collapsed">
                            <Setter Property="Width" Value="0" />
                        </DataTrigger>
                    </Style.Triggers>
                </Style>
            </ColumnDefinition.Style>
        </ColumnDefinition>
    </Grid.ColumnDefinitions>
    <ContentControl x:Name="ccSomeItems" Content="{Binding SomeItems}" Margin="4" Visibility="{Binding SomeItems.AllItems.Count, Converter={StaticResource IntegerToVisibilityConverter}}" />
    <ContentControl Grid.Column="1" Content="{Binding SomeOtherItems}" Margin="4" Visibility="{Binding SomeOtherItems.AllOtherItems.Count, Converter={StaticResource IntegerToVisibilityConverter}}" />
</Grid>

2 回复 | 直到 10 年前

Derrick Moeller 10 年前

我能够运行Rachel的评论,并使用转换器找到解决方案。

XAML:

<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="{Binding Visibility, ElementName=SomeItems, Converter={StaticResource VisibilityToGridLengthConverter}}" />
        <ColumnDefinition Width="{Binding Visibility, ElementName=SomeOtherItems, Converter={StaticResource VisibilityToGridLengthConverter}}" />
    </Grid.ColumnDefinitions>
    <ContentControl x:Name="SomeItems" Content="{Binding SomeItems}" Visibility="{Binding SubPackages.AllPackages.Count, Converter={StaticResource IntegerToVisibilityConverter}}" />
    <ContentControl x:Name="SomeOtherItems" Grid.Column="1" Content="{Binding SomeOtherItems}" Visibility="{Binding Elements.AllElements.Count, Converter={StaticResource IntegerToVisibilityConverter}}" />
</Grid>

以及转换器:

[ValueConversion(typeof(Visibility), typeof(GridLength))]
public class VisibilityToGridLengthConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        return (Visibility)value == Visibility.Collapsed ? new GridLength(0) : new GridLength(1, GridUnitType.Star);
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

GWR 6 年前

我找到了一个更简单的解决方案,那就是用网格元素包围要填充可用空间的元素。因此,使网格成为始终填充可用空间的最后一个元素。网格中的控件可以将其可见性设置为任意值。

    <DockPanel Height="31" HorizontalAlignment="Left" Margin="82,107,0,0" Name="dockPanel1" VerticalAlignment="Top" Width="286" LastChildFill="True">
  <TextBlock Text="Text block" DockPanel.Dock="Left" />
  <Grid>
    <Button Content="Button1" Visibility="Visible" />
    <Button Content="Button2" Visibility="Collapsed" />
  </Grid>
</DockPanel>