强制WPF DataGrid重新生成自己 [英] Force WPF DataGrid to regenerate itself

问题描述

我有一个自定义控件，继承自 DataGrid ，基本上是一个2D DataGrid （接受 ItemsSource 有两个维度，例如 double [，] ）。

I have a custom control which inherits from DataGrid and is basically a 2D DataGrid (accepts an ItemsSource with two dimensions, such as double[,] ).

我添加了一个特定的 DependencyProperty ，它是 ColumnHeaders 和 RowHeaders 所以我可以定义它们。

I added a specific DependencyProperty which is ColumnHeaders and RowHeaders so I can define them.

这是现在的工作原理：

• 我将2D ItemsSource 绑定到 DataGrid


• 包装方法将将此源转换为经典的 IEnumerable 可绑定到实际的datagrid的 ItemsSource


• 自动生成的每行/列都使用事件 AutoGeneratingColumn & AutoGeneratingRow 为了定义他们的标题

• I bind a 2D ItemsSource to the DataGrid
• A wrapper method will take this source to transform it to a classic IEnumerable bindable to the actual datagrid's ItemsSource
• Each row / column auto-generated is done using the events AutoGeneratingColumn & AutoGeneratingRow in order to define their header

当我初始化 DataGrid 时，一切正常。

When I initialize the DataGrid, everything works fine.

之后，我的应用程序的一个用例定义了只有列标题可以改变（通过修改 DependencyProperty ColumnHeaders

After that, one of the use-cases of my application defines that only the column headers can change (by modifying the DependencyProperty ColumnHeaders

而且，无论我在这里做什么， DataGrid 不会重新 - 自动生成其列（因此，标题不会以任何方式更改）。

And, whatever I do here, the DataGrid won't re-autogenerate its columns (and therefore, headers won't be changed in any way).

那么，有没有办法问一下这个 DataGrid 类似嘿，我要你从头重新开始重新生成你的列？因为现在，我无法达到 AutoGeneratingColumn 事件，并调用一个方法，如 InvalidateVisual 将只是重绘网格（而不是重新生成列）。

So, is there a way to ask the DataGrid something like "Hey, I want you to restart from scratch and regenerate your columns" ? Because for now, I can't reach the AutoGeneratingColumn event, and calling a method such as InvalidateVisual will just redraw the grid (and not regenerate columns).

任何想法这里？

我不确定我们需要s ome代码，但...我会放一些所以没有人要求：D

I'm not sure that we need some code but... I'll put some so nobody asks for it :D

    /// <summary>
    /// IList of String containing column headers
    /// </summary>
    public static readonly DependencyProperty ColumnHeadersProperty =
        DependencyProperty.Register("ColumnHeaders",
                                    typeof(IEnumerable),
                                    typeof(FormattedDataGrid2D),
                                    new PropertyMetadata(HeadersChanged));

    /// <summary>
    /// Handler called when the binding on ItemsSource2D changed
    /// </summary>
    /// <param name="source"></param>
    /// <param name="e"></param>
    private static void ItemsSource2DPropertyChanged(DependencyObject source, DependencyPropertyChangedEventArgs e)
    {
        FormattedDataGrid2D @this = source as FormattedDataGrid2D;
        @this.OnItemsSource2DChanged(e.OldValue as IEnumerable, e.NewValue as IEnumerable);
    }

        // (in the constructor)
        AutoGeneratingColumn += new EventHandler<DataGridAutoGeneratingColumnEventArgs>(DataGrid2D_AutoGeneratingColumn);

    void DataGrid2D_AutoGeneratingColumn(object sender, DataGridAutoGeneratingColumnEventArgs e)
    {
        DataGridTextColumn column = e.Column as DataGridTextColumn;
        column.Header = (ColumnHeaders == null) ? columnIndex++ : (ColumnHeaders as IList)[columnIndex++]; //Header will be the defined header OR the column number
        column.Width = new DataGridLength(1.0, DataGridLengthUnitType.Auto);
        Binding binding = column.Binding as Binding;
        binding.Path = new PropertyPath(binding.Path.Path + ".Value"); // Workaround to get a good value to display, do not take care of that
    }

推荐答案

重置您的ItemsSource，它应该重绘您的DataGrid

Reset your ItemsSource and it should redraw your DataGrid

void ResetDataGrid()
{
    var temp = myDataGrid.ItemsSource;
    myDataGrid.ItemsSource = null;
    myDataGrid.ItemsSource = temp;
}

您也可以刷新绑定，但是我还没有测试看看这是否会重新生成DataGrid：

You might also be able to refresh the binding, but I haven't tested it to see if this will actually regenerate the DataGrid:

void ResetDataGrid()
{
    myDataGrid.GetBindingExpression(DataGrid.ItemsSourceProperty).UpdateTarget();
}

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