WPF 4 DataGrid:将行号放入 RowHeader

问题描述 投票:0回答:6

我希望将行号放入 WPF 4 DataGrid 的 RowHeader 中,以便它有一个类似于 Excel 的列用于显示 DataGrid 的行号。

我在网上看到的解决方案建议向业务对象添加索引字段。 这并不是一个真正的选择,因为 DataGrid 将被大量使用,并且我们不想不断跟踪这些索引字段的更改。

非常感谢

wpf wpfdatagrid
6个回答
47
投票

一种方法是将它们添加到

DataGrid
的 LoadingRow 事件中。

<DataGrid Name="DataGrid" LoadingRow="DataGrid_LoadingRow" ... />
void DataGrid_LoadingRow(object sender, DataGridRowEventArgs e)
{
    // Adding 1 to make the row count start at 1 instead of 0
    // as pointed out by daub815
    e.Row.Header = (e.Row.GetIndex() + 1).ToString(); 
}

更新
为了使其能够与 WPF Toolkit 中的 .NET 3.5 DataGrid 一起使用,需要进行一些修改。使用虚拟化时,索引仍然可以正确生成,但输出失败。对

RowHeaderTemplate
的以下修改修复了此问题

<toolkit:DataGrid LoadingRow="DataGrid_LoadingRow">
    <toolkit:DataGrid.RowHeaderTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding RelativeSource={RelativeSource AncestorType={x:Type toolkit:DataGridRow}},
                                      Path=Header}"/>
        </DataTemplate>
    </toolkit:DataGrid.RowHeaderTemplate>
</toolkit:DataGrid>

编辑2012-07-05
如果从源列表中添加或删除项目,则数字会不同步,直到滚动列表,从而再次调用

LoadingRow
。解决这个问题有点复杂,我现在能想到的最好的解决方案是保留上面的
LoadingRow
解决方案以及

  • 订阅
    dataGrid.ItemContainerGenerator.ItemsChanged
  • 在事件处理程序中,找到可视化树中的所有子项
    DataGridRows
  • 将标题设置为每个
    DataGridRow
  • 的索引

这是执行此操作的附加行为。像这样使用

<DataGrid ItemsSource="{Binding ...}"
          behaviors:DataGridBehavior.DisplayRowNumber="True">

显示行号

public class DataGridBehavior
{
    #region DisplayRowNumber

    public static DependencyProperty DisplayRowNumberProperty =
        DependencyProperty.RegisterAttached("DisplayRowNumber",
                                            typeof(bool),
                                            typeof(DataGridBehavior),
                                            new FrameworkPropertyMetadata(false, OnDisplayRowNumberChanged));
    public static bool GetDisplayRowNumber(DependencyObject target)
    {
        return (bool)target.GetValue(DisplayRowNumberProperty);
    }
    public static void SetDisplayRowNumber(DependencyObject target, bool value)
    {
        target.SetValue(DisplayRowNumberProperty, value);
    }

    private static void OnDisplayRowNumberChanged(DependencyObject target, DependencyPropertyChangedEventArgs e)
    {
        DataGrid dataGrid = target as DataGrid;
        if ((bool)e.NewValue == true)
        {
            EventHandler<DataGridRowEventArgs> loadedRowHandler = null;
            loadedRowHandler = (object sender, DataGridRowEventArgs ea) =>
            {
                if (GetDisplayRowNumber(dataGrid) == false)
                {
                    dataGrid.LoadingRow -= loadedRowHandler;
                    return;
                }
                ea.Row.Header = ea.Row.GetIndex();
            };
            dataGrid.LoadingRow += loadedRowHandler;

            ItemsChangedEventHandler itemsChangedHandler = null;
            itemsChangedHandler = (object sender, ItemsChangedEventArgs ea) =>
            {
                if (GetDisplayRowNumber(dataGrid) == false)
                {
                    dataGrid.ItemContainerGenerator.ItemsChanged -= itemsChangedHandler;
                    return;
                }
                GetVisualChildCollection<DataGridRow>(dataGrid).
                    ForEach(d => d.Header = d.GetIndex());
            };
            dataGrid.ItemContainerGenerator.ItemsChanged += itemsChangedHandler;
        }
    }

    #endregion // DisplayRowNumber

    #region Get Visuals

    private static List<T> GetVisualChildCollection<T>(object parent) where T : Visual
    {
        List<T> visualCollection = new List<T>();
        GetVisualChildCollection(parent as DependencyObject, visualCollection);
        return visualCollection;
    }

    private static void GetVisualChildCollection<T>(DependencyObject parent, List<T> visualCollection) where T : Visual
    {
        int count = VisualTreeHelper.GetChildrenCount(parent);
        for (int i = 0; i < count; i++)
        {
            DependencyObject child = VisualTreeHelper.GetChild(parent, i);
            if (child is T)
            {
                visualCollection.Add(child as T);
            }
            if (child != null)
            {
                GetVisualChildCollection(child, visualCollection);
            }
        }
    }

    #endregion // Get Visuals
}

9
投票

编辑:显然滚动会更改索引,因此绑定不会像那样工作......

(看似)干净的模板解决方案:
XAML:

<Window
    ...
    xmlns:local="clr-namespace:Test"
    DataContext="{Binding RelativeSource={RelativeSource Mode=Self}}">
    <Window.Resources>
        <local:RowToIndexConv x:Key="RowToIndexConv"/>
    </Window.Resources>
        <DataGrid ItemsSource="{Binding GridData}">
            <DataGrid.RowHeaderTemplate>
                <DataTemplate>
                    <TextBlock Margin="2" Text="{Binding RelativeSource={RelativeSource AncestorType=DataGridRow}, Converter={StaticResource RowToIndexConv}}"/>
                </DataTemplate>
            </DataGrid.RowHeaderTemplate>
        </DataGrid>
</Window>

转换器:

public class RowToIndexConv : IValueConverter
{

    #region IValueConverter Members

    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        DataGridRow row = value as DataGridRow;
        return row.GetIndex() + 1;
    }

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

    #endregion
}

3
投票

如果添加或删除行,所有这些方法都将不起作用。在这种情况下,您应该刷新行索引。看看这个行为:

public static class DataGridBehavior
{
    #region RowNumbers property

    public static readonly DependencyProperty RowNumbersProperty =
        DependencyProperty.RegisterAttached("RowNumbers", typeof (bool), typeof (DataGridBehavior), 
        new FrameworkPropertyMetadata(false, OnRowNumbersChanged));

    private static void OnRowNumbersChanged(DependencyObject source, DependencyPropertyChangedEventArgs args)
    {
        DataGrid grid = source as DataGrid;
        if (grid == null)
            return;
        if ((bool)args.NewValue)
        {
            grid.LoadingRow += onGridLoadingRow;
            grid.UnloadingRow += onGridUnloadingRow;
        }
        else
        {
            grid.LoadingRow -= onGridLoadingRow;
            grid.UnloadingRow -= onGridUnloadingRow;
        }
    }

    private static void refreshDataGridRowNumbers(object sender)
    {
        DataGrid grid = sender as DataGrid;
        if (grid == null)
            return;

        foreach (var item in grid.Items)
        {
            var row = (DataGridRow)grid.ItemContainerGenerator.ContainerFromItem(item);
            if (row != null)
                row.Header = row.GetIndex() + 1;
        }
    }

    private static void onGridUnloadingRow(object sender, DataGridRowEventArgs e)
    {
        refreshDataGridRowNumbers(sender);
    }

    private static void onGridLoadingRow(object sender, DataGridRowEventArgs e)
    {
        refreshDataGridRowNumbers(sender);
    }

    [AttachedPropertyBrowsableForType(typeof(DataGrid))]
    public static void SetRowNumbers(DependencyObject element, bool value)
    {
        element.SetValue(RowNumbersProperty, value);
    }

    public static bool GetRowNumbers(DependencyObject element)
    {
        return (bool) element.GetValue(RowNumbersProperty);
    }

    #endregion
}

1
投票

@Fredrik Hedblad 的答案对我有用。谢谢!

我添加了另一个属性来获取“偏移”值,以便 DataGrid 可以从 0 或 1(或任何设置的值)开始。

要使用该行为,(注意“b”是命名空间)

<DataGrid ItemsSource="{Binding ...}"
      b:DataGridBehavior.DisplayRowNumberOffset="1"
      b:DataGridBehavior.DisplayRowNumber="True">

修改后的类:

/// <summary>
/// Collection of DataGrid behavior
/// </summary>
public static class DataGridBehavior
{
    #region DisplayRowNumberOffset

    /// <summary>
    /// Sets the starting value of the row header if enabled
    /// </summary>
    public static DependencyProperty DisplayRowNumberOffsetProperty =
        DependencyProperty.RegisterAttached("DisplayRowNumberOffset",
                                            typeof(int),
                                            typeof(DataGridBehavior),
                                            new FrameworkPropertyMetadata(0, OnDisplayRowNumberOffsetChanged));

    public static int GetDisplayRowNumberOffset(DependencyObject target)
    {
        return (int)target.GetValue(DisplayRowNumberOffsetProperty);
    }

    public static void SetDisplayRowNumberOffset(DependencyObject target, int value)
    {
        target.SetValue(DisplayRowNumberOffsetProperty, value);
    }

    private static void OnDisplayRowNumberOffsetChanged(DependencyObject target, DependencyPropertyChangedEventArgs e)
    {
        DataGrid dataGrid = target as DataGrid;
        int offset = (int)e.NewValue;

        if (GetDisplayRowNumber(target))
        {
            WPFUtil.GetVisualChildCollection<DataGridRow>(dataGrid).
                    ForEach(d => d.Header = d.GetIndex() + offset);
        }
    }

    #endregion

    #region DisplayRowNumber

    /// <summary>
    /// Enable display of row header automatically
    /// </summary>
    /// <remarks>
    /// Source: 
    /// </remarks>
    public static DependencyProperty DisplayRowNumberProperty =
        DependencyProperty.RegisterAttached("DisplayRowNumber",
                                            typeof(bool),
                                            typeof(DataGridBehavior),
                                            new FrameworkPropertyMetadata(false, OnDisplayRowNumberChanged));

    public static bool GetDisplayRowNumber(DependencyObject target)
    {
        return (bool)target.GetValue(DisplayRowNumberProperty);
    }

    public static void SetDisplayRowNumber(DependencyObject target, bool value)
    {
        target.SetValue(DisplayRowNumberProperty, value);
    }

    private static void OnDisplayRowNumberChanged(DependencyObject target, DependencyPropertyChangedEventArgs e)
    {
        DataGrid dataGrid = target as DataGrid;
        if ((bool)e.NewValue == true)
        {
            int offset = GetDisplayRowNumberOffset(target);

            EventHandler<DataGridRowEventArgs> loadedRowHandler = null;
            loadedRowHandler = (object sender, DataGridRowEventArgs ea) =>
            {
                if (GetDisplayRowNumber(dataGrid) == false)
                {
                    dataGrid.LoadingRow -= loadedRowHandler;
                    return;
                }
                ea.Row.Header = ea.Row.GetIndex() + offset;
            };
            dataGrid.LoadingRow += loadedRowHandler;

            ItemsChangedEventHandler itemsChangedHandler = null;
            itemsChangedHandler = (object sender, ItemsChangedEventArgs ea) =>
            {
                if (GetDisplayRowNumber(dataGrid) == false)
                {
                    dataGrid.ItemContainerGenerator.ItemsChanged -= itemsChangedHandler;
                    return;
                }
                WPFUtil.GetVisualChildCollection<DataGridRow>(dataGrid).
                    ForEach(d => d.Header = d.GetIndex() + offset);
            };
            dataGrid.ItemContainerGenerator.ItemsChanged += itemsChangedHandler;
        }
    }

    #endregion // DisplayRowNumber
}

0
投票

LoadingRowEvent 是这样触发的:

ICollectionView view = CollectionViewSource.GetDefaultView(_dataGrid.ItemsSource);
view.Refresh();

0
投票

另一个解决方案与上面的答案有些相似,但有一些限制和巨大的优势。


    IValueConverter
  1. 必须绑定到实现
    ItemsSource
    的集合,因为需要方法
    IList
    来查找项目的索引。
    IndexOf
    这里很好。
    收藏品必须是参考类型。
  2. 该解决方案的优点是独立于
ObservableCollection<T>

的虚拟化类型。特别是默认虚拟化设置有效。因此它可以在相当大的虚拟化网格中正常工作。

首先我们需要一个多值转换器:

DataGrid

然后在XAML资源中注册:

public class RowIndexConverter : IMultiValueConverter { public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture) { if (values.Length == 2 && values[1] is IList items) { int index = items.IndexOf(values[0]); if (index >= 0) { return $"{index + 1}"; } } return string.Empty; } public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture) { throw new NotSupportedException(); } }

然后使用
<Window.Resources> <local:RowIndexConverter x:Key="RowIndexConverter"/> </Window.Resources>

的行标题模板中的转换器:

DataGrid

就是这样。

© www.soinside.com 2019 - 2024. All rights reserved.