ItemsControl - 网格子元素自动调整大小

Question

我正在使用 Rachel Lim 的 GridHelper 来获取动态行数。我想要实现的是让每一行显示在另一行下方（完成），能够调整它们的大小（完成 - 使用 GridSplitter）并根据屏幕大小按比例调整内容大小。

结果：

我想要的：

Xaml：

<Grid>
    <ItemsControl ItemsSource="{Binding RowSource}" >
        <ItemsControl.ItemsPanel>
            <ItemsPanelTemplate>
                <Grid local:GridHelper.RowCount="{Binding RowCount}" />
            </ItemsPanelTemplate>
        </ItemsControl.ItemsPanel>
        <ItemsControl.ItemContainerStyle>
            <Style TargetType="ContentPresenter">
                <Setter Property="Grid.Row" Value="{Binding RowNumber}"/>
            </Style>
        </ItemsControl.ItemContainerStyle>
        <ItemsControl.ItemTemplate>
            <DataTemplate>
                <Grid>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto"/>
                        <RowDefinition Height="Auto"/>
                    </Grid.RowDefinitions>
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="Auto" />
                        </Grid.ColumnDefinitions>
                        <DataGrid>
                            <DataGrid.Columns>
                                <DataGridTextColumn Header="Col 1" />
                                <DataGridTextColumn Header="Col 2" />
                                <DataGridTextColumn Header="Col 3" />
                            </DataGrid.Columns>
                        </DataGrid>
                        <Button Grid.Column="1" Content="Btn" />
                    </Grid>
                    <GridSplitter Height="5" VerticalAlignment="Bottom" HorizontalAlignment="Stretch" Grid.Row="0" ResizeDirection="Rows" ResizeBehavior="CurrentAndNext"/>
                </Grid>
            </DataTemplate>
        </ItemsControl.ItemTemplate>
    </ItemsControl>
</Grid>

视图模型：

internal class MyViewModel
{
    public ObservableCollection<RowInfo> RowSource { get; set; }

    public int RowCount { get { return RowSource.Count; } }

    public MyViewModel()
    {
        RowSource = new ObservableCollection<RowInfo>()
        {
            new RowInfo() { RowNumber = 0 },
            new RowInfo() { RowNumber = 1 },
            new RowInfo() { RowNumber = 2 }
        };
    }
}

行信息：

public class RowInfo
{
    public int RowNumber { get; internal set; }
}

Answer 1

我认为你的方法完全错误。您不能使用ItemsControl，因为GridSplitter 项目需要位于ItemsPanel 级别而不是DataTemplate - 否则，它将不起作用。

最好在网格本身上使用自定义行为 - 请参阅下面的示例代码：

public class GridAutoRowChildBehavior : Behavior<Grid>
{
    public static readonly DependencyProperty ItemTemplateProperty =
        DependencyProperty.Register("ItemTemplate", typeof(DataTemplate), typeof(GridAutoRowChildBehavior),
            new PropertyMetadata(null, OnGridPropertyChanged));

    public static readonly DependencyProperty ItemsSourceProperty =
        DependencyProperty.Register("ItemsSource", typeof(object), typeof(GridAutoRowChildBehavior),
            new PropertyMetadata(null, OnGridPropertyChanged));

    private static void OnGridPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        ((GridAutoRowChildBehavior) d).ResetGrid();
    }

    private void ResetGrid()
    {
        var source = ItemsSource as IEnumerable;
        if (source == null || ItemTemplate == null)
            return;
        AssociatedObject.Children.Clear();
        AssociatedObject.RowDefinitions.Clear();
        var count = 0;
        foreach (var item in source)
        {
            var content = new ContentPresenter
            {
                ContentTemplate = ItemTemplate,
                Content = item
            };
            var splitter = new GridSplitter
            {
                Height = 5,
                VerticalAlignment = VerticalAlignment.Bottom,
                HorizontalAlignment = HorizontalAlignment.Stretch
            };
            AssociatedObject.RowDefinitions.Add(new RowDefinition { Height = new GridLength(1, GridUnitType.Star) });
            Grid.SetRow(content,count);
            Grid.SetRow(splitter,count);
            AssociatedObject.Children.Add(content);
            AssociatedObject.Children.Add(splitter);
            count++;
        }

    }

    public DataTemplate ItemTemplate
    {
        get { return (DataTemplate) GetValue(ItemTemplateProperty); }
        set { SetValue(ItemTemplateProperty, value); }
    }


    public object ItemsSource
    {
        get { return GetValue(ItemsSourceProperty); }
        set { SetValue(ItemsSourceProperty, value); }
    }
}

然后在您的 XAML 中，您将其编码如下：

<Grid>
    <i:Interaction.Behaviors>
        <local:GridAutoRowChildBehavior ItemsSource="{Binding RowsSource}">
            <local:GridAutoRowChildBehavior.ItemTemplate>
                <DataTemplate>
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="Auto" />
                        </Grid.ColumnDefinitions>
                        <DataGrid>
                            <DataGrid.Columns>
                                <DataGridTextColumn Header="Col 1" />
                                <DataGridTextColumn Header="Col 2" />
                                <DataGridTextColumn Header="Col 3" />
                            </DataGrid.Columns>
                        </DataGrid>
                        <Button Grid.Column="1" Content="Btn" />
                    </Grid>
                </DataTemplate>
            </local:GridAutoRowChildBehavior.ItemTemplate>
        </local:GridAutoRowChildBehavior>
    </i:Interaction.Behaviors>
</Grid>

我已经对此进行了测试，它完全符合您的需要。

您唯一需要做的就是将 Nuget 包 Systems.Windows.Interactivity.WPF 添加到您的项目中

Answer 2

对您在GridHelper 类中创建的RowDefintions 使用星号：

public static void RowCountChanged(
    DependencyObject obj, DependencyPropertyChangedEventArgs e)
{
    if (!(obj is Grid) || (int)e.NewValue < 0)
        return;

    Grid grid = (Grid)obj;
    grid.RowDefinitions.Clear();

    for (int i = 0; i < (int)e.NewValue; i++)
        grid.RowDefinitions.Add(
            new RowDefinition() { Height = new GridLength(1, GridUnitType.Star) }); //<--

    SetStarRows(grid);
}

并将您的第一个RowDefinition 的Height 设置为*：

<ItemsControl.ItemTemplate>
    <DataTemplate>
        <Grid Background="Yellow">
            <Grid.RowDefinitions>
                <RowDefinition Height="*"/>
                <RowDefinition Height="Auto"/>
            </Grid.RowDefinitions>
            <Grid>
                <Grid.ColumnDefinitions>
                    <ColumnDefinition Width="*" />
                    <ColumnDefinition Width="Auto" />
                </Grid.ColumnDefinitions>
                <DataGrid>
                    <DataGrid.Columns>
                        <DataGridTextColumn Header="Col 1" />
                        <DataGridTextColumn Header="Col 2" />
                        <DataGridTextColumn Header="Col 3" />
                    </DataGrid.Columns>
                </DataGrid>
                <Button Grid.Column="1" Content="Btn" />
            </Grid>
            <GridSplitter Height="5" VerticalAlignment="Bottom" HorizontalAlignment="Stretch" Grid.Row="0" ResizeDirection="Rows" ResizeBehavior="CurrentAndNext"/>
        </Grid>
    </DataTemplate>
</ItemsControl.ItemTemplate>