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MVVM DataGrid如何在刷新内容后设置焦点

datagrid mvvm wpf c#

Kerwen · 技术社区 · 7 年前

我有一个 DataGrid 如下所示:

<DataGrid ItemsSource="{Binding GridSource}" CanUserAddRows="False"
          AutoGenerateColumns="False"
          SelectedItem="{Binding SelectedRow, Mode=TwoWay}">
...
</DataGrid>

我有个计时器 ViewModel 刷新的内容 数据网格 ,更新内容后,使用 SelectedRow 要重置当前行,请选择行。

检查UI结果,所选行正常,但没有蓝色背景。我想我错过了设置焦点,但如何实现这一点?

1 回复 | 直到 3 年前

Toni rai nalasa 3 年前

我想我错过了设置焦点,但如何实现这一点?

以编程方式聚焦 DataGrid 要获得与使用鼠标单击行时完全相同的行为,需要付出一些努力。详情请参阅以下博文。

How to programmatically select and focus a row or cell in a DataGrid in WPF

private static void SelectRowByIndex(DataGrid dataGrid, int rowIndex)
{
    if (!dataGrid.SelectionUnit.Equals(DataGridSelectionUnit.FullRow))
        throw new ArgumentException(
        "The SelectionUnit of the DataGrid must be set to FullRow.");
    if (rowIndex < 0 || rowIndex > (dataGrid.Items.Count - 1))
        throw new ArgumentException(string.Format(
        "{0} is an invalid row index.", rowIndex));
    dataGrid.SelectedItems.Clear();
    /* set the SelectedItem property */
    object item = dataGrid.Items[rowIndex]; // = Product X
    dataGrid.SelectedItem = item;
    DataGridRow row =
        dataGrid.ItemContainerGenerator.ContainerFromIndex(rowIndex)
        as DataGridRow;
    if (row == null)
    {
        /* bring the data item (Product object) into view
         * in case it has been virtualized away */
        dataGrid.ScrollIntoView(item);
        row = dataGrid.ItemContainerGenerator
            .ContainerFromIndex(rowIndex) as DataGridRow;
    }
    if (row != null)
    {
        DataGridCell cell = GetCell(dataGrid, row, 0);
        if (cell != null)
            cell.Focus();
    }
}

private static DataGridCell GetCell(DataGrid dataGrid,
    DataGridRow rowContainer, int column)
{
    if (rowContainer != null)
    {
        DataGridCellsPresenter presenter =
            FindVisualChild<DataGridCellsPresenter>(rowContainer);
        if (presenter == null)
        {
            /* if the row has been virtualized away, call its
             * ApplyTemplate() method 
             * to build its visual tree in order for the
             * DataGridCellsPresenter
             * and the DataGridCells to be created */
            rowContainer.ApplyTemplate();
            presenter =
                FindVisualChild<DataGridCellsPresenter>(rowContainer);
        }
        if (presenter != null)
        {
            DataGridCell cell =
            presenter.ItemContainerGenerator.ContainerFromIndex(column)
            as DataGridCell;
            if (cell == null)
            {
                /* bring the column into view
                 * in case it has been virtualized away */
                dataGrid.ScrollIntoView(rowContainer,
                    dataGrid.Columns[column]);
                cell =
                    presenter.ItemContainerGenerator
                    .ContainerFromIndex(column) as DataGridCell;
            }
            return cell;
        }
    }
    return null;
}

private static T FindVisualChild<T>(DependencyObject obj)
    where T : DependencyObject
{
    for (int i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
    {
        DependencyObject child = VisualTreeHelper.GetChild(obj, i);
        if (child != null && child is T)
            return (T)child;
        else
        {
            T childOfChild = FindVisualChild<T>(child);
            if (childOfChild != null)
                return childOfChild;
        }
    }
    return null;
}