Select all check boxes WPF

Question

I want to make all check boxes selected by selecting check box names with "All of Above". the checkboxes are in a List box

<ListBox SelectionMode="Multiple" 
         BorderThickness="0" 
         ItemsSource="{Binding QuestionThreeSelection}" 
         SelectedItem="{Binding QuestionThreeSelection}" 
         Name="listBoxList" 
         SelectionChanged="listBoxList_SelectionChanged">
    <ListBox.InputBindings>
        <KeyBinding Command="ApplicationCommands.SelectAll"
                    Modifiers="Ctrl"
                    Key="A" />
    </ListBox.InputBindings>
    <ListBox.ItemTemplate>
        <DataTemplate>
            <CheckBox Checked="CheckBox_Checked_1"   
                      Content="{Binding SourceName}" 
                      IsChecked="{Binding Path=IsSelected,  Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" />
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

back Code

private void CheckBox_Checked_1(object sender, RoutedEventArgs e)
{          
    var oo = listBoxList;
    CheckBox cb = (CheckBox)sender;
    //var w=e;

    IEnumerable<AddSource> listallityem = ((IEnumerable<AddSource>)listBoxList.Items.SourceCollection).Where(r => r.IsSelected == false);
    //IEnumerable<AddSource> listallityem1 = ((IEnumerable<AddSource>)listBoxList.Items.SourceCollection);

    AddSource vv = cb.DataContext as AddSource;
    if ((bool) cb.IsChecked)
    {

    }

    if (vv.SourceName== "All of the above")
    {
        r = listBoxList.ItemsSource;

        foreach (AddSource item in wer)
        {
            item.IsSelected = true; // false in case of unselect
        }
    }
}

Can someone suggest a method?

Answer 1

You could handle the Checked and Unchecked event for your "All of Above" CheckBox something like this:

private void CheckBox_Checked(object sender, RoutedEventArgs e)
{
    SelectAll(true);
}

private void CheckBox_Unchecked(object sender, RoutedEventArgs e)
{
    SelectAll(false);
}

private void SelectAll(bool select)
{
    var all = listBoxList.ItemsSource as IEnumerable<AddSource>;
    if (all != null)
    {
        foreach (var source in all)
            source.IsSelected = select;
    }
}

Make sure that your AddSource class implements the INotifyPropertyChanged and raise the PropertyChanged event in the setter of the IsSelected property.