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Access to checkbox in wpf datagrid header

Hei

I need help determining access to the checkbox in the datagrid wpf header. Here is what I have:

<DataGrid.Columns>
    <DataGridTemplateColumn CanUserReorder="False" CanUserResize="False">
        <DataGridTemplateColumn.HeaderTemplate>
            <DataTemplate>
                <CheckBox Name="cbxAll" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" HorizontalAlignment="Center" VerticalAlignment="Center" />
            </DataTemplate>
        </DataGridTemplateColumn.HeaderTemplate>
        <DataGridTemplateColumn.CellTemplate>
            <DataTemplate>
                <CheckBox IsChecked="{Binding Path=Checked, UpdateSourceTrigger=PropertyChanged}" IsEnabled="{Binding Path=NoErrors}" Name="theCheckbox" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" HorizontalAlignment="Center" VerticalAlignment="Center" />
            </DataTemplate>
        </DataGridTemplateColumn.CellTemplate>
    </DataGridTemplateColumn>
</DataGrid.Columns>

I set Namefor the checkbox, but for some reason I cannot access it from the code side.

I need to check the box to uncheck the box after updating my datagrid elements. How can i do this?

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3 answers

A universal commitment can be what you have to go, you can do what you ask. Here is one way to do this:

1. Enter your CheckBoxUid header

<CheckBox Uid="CheckAll" />

2. write your DataGrid

<DataGrid Name="myDataGrid" />

3.Use the following extension method

public static UIElement FindUid(this DependencyObject parent, string uid)
{
    var count = VisualTreeHelper.GetChildrenCount(parent);
    if (count == 0) return null;

    for (int i = 0; i < count; i++)
    {
        var el = VisualTreeHelper.GetChild(parent, i) as UIElement;
        if (el == null) continue;

        if (el.Uid == uid) return el;

        el = el.FindUid(uid);
        if (el != null) return el;
    }
    return null;
}

4.Access and uncheck the CheckBoxcode like this

CheckBox checkBox = myDataGrid.FindUid("CheckAll") as CheckBox;
checkBox.IsChecked = false;
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MVVM:

ViewModel

public class MainWindowViewModel : INotifyPropertyChanged
{
    private bool allItemsAreChecked;

    public event PropertyChangedEventHandler PropertyChanged;

    public bool AllItemsAreChecked
    {
        get
        {
            return this.allItemsAreChecked;
        }
        set
        {
            this.allItemsAreChecked = value;
            var handler = this.PropertyChanged;
            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs("AllItemsAreChecked"));
            }
        }
    }
}

XAML

<DataGridTemplateColumn CanUserReorder="False" CanUserResize="False">
    <DataGridTemplateColumn.HeaderTemplate>
        <DataTemplate>
            <CheckBox IsChecked="{Binding
                RelativeSource={RelativeSource AncestorType={x:Type DataGrid}},
                Path=DataContext.AllItemsAreChecked}" />
        </DataTemplate>
    </DataGridTemplateColumn.HeaderTemplate>
</DataGridTemplateColumn>
+7

:

<CheckBox x:Name="cbxAll" Click="cbxAll_Click"/>

:

private void cbxAll_Click(object sender, RoutedEventArgs e)
{
   var ckbox = sender as CheckBox;
   if (ckbox.IsChecked == true)
   {
    //Check all itens
   }
   else
   {
    //Uncheck all itens
   }
}

NOTE. The sender has a flag

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