GridSplitter自动调整大小

Question

我的GridSplitter出了点问题

简单的示例代码：

<Grid x:Name="MainGrid">
    <Grid.RowDefinitions>
        <RowDefinition Height="100"></RowDefinition>
        <RowDefinition Height="2"></RowDefinition>
        <RowDefinition Height="*"></RowDefinition>
    </Grid.RowDefinitions>
    <Grid x:Name="TopGrid" Grid.Row="0"  HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Background="Red"/>
    <GridSplitter ResizeDirection="Rows" Grid.Row="1" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Height="2" Background="Black" />
    <Grid x:Name="BottomGrid" Grid.Row="2" HorizontalAlignment="Stretch"  Background="Aquamarine" VerticalAlignment="Stretch"/>
</Grid>

这将创建由GridSplitter垂直分隔的两个网格。

我想要实现的是，GridSplitter自动与网格的内容对齐。例如，如果我在底部网格中有一个可折叠的元素，如果我折叠该元素，我希望顶部网格变得更大。如果我展开它，顶部的Grid应该会变得更小。

我该怎么做呢？稍后我将有4个带有3个GridSplitter的Grids…因此，该解决方案也应该适用于多个GridSplitter。

编辑

我的xaml：

 <Grid x:Name="MainGrid">
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*"/>
    </Grid.ColumnDefinitions>
    <Grid.RowDefinitions>
        <RowDefinition Height="100">
            <RowDefinition.MinHeight>
                <MultiBinding Converter="{StaticResource ResourceKey=MultiValueConverter}">
                    <Binding ElementName="dgStapelliste" Path="ActualHeight"></Binding>
                </MultiBinding>
            </RowDefinition.MinHeight>
        </RowDefinition>
        <RowDefinition Height="1"></RowDefinition>
        <RowDefinition Height="*"></RowDefinition >           
    </Grid.RowDefinitions>

    <Grid Grid.Row="0" Grid.Column="0" x:Name="Test">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="200"/>
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <WPF:DataGrid GridHeaderContent="{Binding StapelListe.HeaderText}" SelectedItem="{Binding StapelListe.SelectedItem}" Grid.Row="0" Grid.Column="0" x:Name="dgStapelliste" HorizontalAlignment="Stretch" ItemsSource="{Binding StapelListe, Mode=OneWay,  UpdateSourceTrigger=PropertyChanged}"/>
        <WPF:DataGrid GridHeaderContent="{Binding EinzelListe.HeaderText}" Grid.Row="0" Grid.Column="1" x:Name="dgEinzelliste" HorizontalAlignment="Stretch"  ItemsSource="{Binding EinzelListe, Mode=OneWay}"/>

        <GridSplitter Grid.Column="0" Width="1" VerticalAlignment="Stretch" Background="Black" />
    </Grid>

    <Grid Grid.Row="2" Grid.Column="0" Grid.RowSpan="2">
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="200"/>
        </Grid.ColumnDefinitions>

        <WPF:DataGrid  GridHeaderContent="{Binding Anforderungsliste.HeaderText}" Grid.Column="0" x:Name="dgAnforderungsliste" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" ItemsSource="{Binding Anforderungsliste, Mode=OneWay}"/>

        <GridSplitter Grid.Column="0" Width="1" VerticalAlignment="Stretch" Background="Black" />
    </Grid>
    <GridSplitter Grid.Column="0" Grid.Row="1" Height="1" ResizeDirection="Rows"  VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Background="Black" x:Name="testSplitter" />
</Grid>

Answer 1

您可以使用MultiBinding来实现您想要的功能。

为每个RowDefinition设置一个绑定到其内容的MinHeight，如下所示：

<RowDefinition Height="100">
    <RowDefinition.MinHeight>
        <MultiBinding Converter="{StaticResource ResourceKey=CalcAll}">
            <Binding ElementName="firstElementInThisRow" Path="ActualHeight"></Binding>
            <Binding ElementName="secondElementInThisRow" Path="ActualHeight"></Binding>
            <Binding ElementName="thirdElementInThisRow" Path="ActualHeight"></Binding>
            <Binding ElementName="fourthElementInThisRow" Path="ActualHeight"></Binding>
        </MultiBinding>
    </RowDefinition.MinHeight>
</RowDefinition>

您的转换器可能如下所示：

public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
    double result = 0.0;
    foreach (object item in values)
    {
        result += System.Convert.ToDouble(item);
    }
    return result;
}

public object[] ConvertBack(object values, Type[] targetType, object parameter, CultureInfo culture)
{
    return null;
}

每次展开控件时，它的ActualHeight都会更改，绑定也会更新父RowDefinition的MinHeight。

但是，如果控件的VerticalAlignment设置为Stretch，则不能将其设置为Stretch，因为这样ActualHeight就不会因为展开而改变。

编辑：因为我现在能想到的唯一属性是DesiredSize.Height- property，所以你不能使用绑定(如果DesiredSize.Height-value发生变化，绑定就不会更新)。但也许您可以使用double类型的属性(让我们称其为MinHeightRowOne)，它在其setter中引发PropertyChanged事件，并绑定到前几行MinHeight (每行一个属性)：

public double _minHeightRowOne;
public double MinHeightRowOne
{
    get
    {
        return _minHeightRowOne;
    }
    set
    {
        _minHeightRowOne = value;
        OnPropertyChanged("MinHeightRowOne");
    }
}

public event PropertyChangedEventHandler PropertyChanged;
public void OnPropertyChanged(string name)
{
    if (PropertyChanged != null)
    {
        PropertyChanged(this, new PropertyChangedEventArgs(name));
    }
}

<RowDefinition Height="100" MinHeight="{Binding Path=MinHeightRowOne}"/>

现在将此事件添加到第一行中每个控件的SizeChanged- EventHandler中(每行一个处理程序)：

private List<KeyValuePair<string,double>> oldVals = new List<KeyValuePair<string,double>>();

private void ElementInRowOneSizeChanged(object sender, SizeChangedEventArgs e)
{
    FrameworkElement elem = (FrameworkElement)sender;
    MinHeightRowOne -= oldVals.Find(kvp => kvp.Key == elem.Name).Value;
    elem.Measure(new Size(int.MaxValue, int.MaxValue));
    MinHeightRowOne += elem.DesiredSize.Height;
    oldVals.Remove(oldVals.Find(kvp => kvp.Key == elem.Name));
    oldVals.Add(new KeyValuePair<string, double>(elem.Name, elem.DesiredSize.Height));
}

通过这种方式，每次控件的大小发生变化(应该包括展开或折叠项)时，行的MinHeight都会更新。

请注意，每个控件都必须有一个唯一的名称才能使其工作。