Loop through checked checkboxes in grid and get lable values WPF c#

Question

i have a grid,inside that grid there's a stackpanel inside which there is one Checkbox and 2 TextBlocks. The XAML is :

  <Grid x:name="maingrid" >
    <Stackpanel x:name="panel1">
       <Checkbox height="10" width="10"/>
       <Textblock x:name="name1" text="a"/>
       <Textblock x:name="name2" text="b"/>
       <Textblock x:name="name3" text="c"/>
     </Stackpanel>
   </Grid>

Now, the thing is, inside MainGrid, I am dynamically adding panel1 (the stackpanel) based on a list of random text. Anyway, what i want is , when i check the checkbox, the releavent Stackpanel(panel1)'s textblock values(name1,name2,name3's values) would be passed to a List(Of string) from where I can get the values of the three textblocks of each checked Checkboxes in stackpanels... Somewhat like the DataGrid/DataGridView (winforms) ..

I beg your pardon if I failed to describe my wants properly but I hope you can understand what I'm looking for. I found this but as my motive and situation is entirely different, i can't really make use of the answer in that post... Any help/explanation of my idea ?

UPDATE : A more logical/better explanation If i have a UserControl with 1 checkbox and 2 textblocks and populate a Window's grid with the usercontrol based on datarows derived from a datatable, how do i get the textblock values of the checked checkboxes of the UserControl?

Answer 1

Don't try to work with XAML as you worked with WinForms. It's a dead-end.
Use MVVM, data binding, and work with data first of all.

Here's sample view model for "stack panel"s and their content:

public sealed class ItemViewModel : ViewModelBase
{
    private bool isChecked;

    public bool IsChecked
    {
        get { return isChecked; }
        set
        {
            if (isChecked != value)
            {
                isChecked = value;
                OnPropertyChanged();
            }
        }
    }

    public string Name1 { get; set; }

    public string Name2 { get; set; }
}

ViewModelBase is a basic INotifyPropertyChanged implementation (google it).

Next, view model for sample application:

public sealed class MainViewModel
{
    private ObservableCollection<ItemViewModel> items;

    public ObservableCollection<ItemViewModel> Items
    {
        get
        {
            if (items == null)
            {
                items = new ObservableCollection<ItemViewModel>();
                items.CollectionChanged += ItemsCollectionChanged;
            }

            return items;
        }
    }

    private void ItemsCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        switch (e.Action)
        {
            case NotifyCollectionChangedAction.Add:
                // we want to be notified, if IsChecked is changed;
                // ObservableCollection<T> adds one item per time, so, we just using NewItems[0]
                ((ItemViewModel)e.NewItems[0]).PropertyChanged += ItemPropertyChanged;
                break;
            case NotifyCollectionChangedAction.Remove:
                // we need to unsibscribe, when removing item from collection,
                // to avoid memory leak
                ((ItemViewModel)e.OldItems[0]).PropertyChanged -= ItemPropertyChanged;
                break;
        }
    }

    private void ItemPropertyChanged(object sender, PropertyChangedEventArgs e)
    {
        // we're interested only in IsCheckedProperty
        if (e.PropertyName == nameof(ItemViewModel.IsChecked))
        {
            // let's update our list
            UpdateItemTextValues();
        }
    }

    private void UpdateItemTextValues()
    {
        // retrieving NameN property values from checked items as a single list
        var itemTextValues = Items
            .Where(_ => _.IsChecked)
            .Select(_ => new[]
            {
                _.Name1,
                _.Name2
            })
            .SelectMany(_ => _)
            .ToList();

        // do somethig with the list
        Trace.WriteLine(null);

        foreach (var value in itemTextValues)
        {
            Trace.WriteLine(value);
        }
    }
}

XAML. Note, that you don't need Grid, use ItemsControl instead:

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApplication1"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525">
    <ItemsControl ItemsSource="{Binding Items}">
        <ItemsControl.ItemTemplate>
            <DataTemplate DataType="{x:Type local:ItemViewModel}">
                <StackPanel>
                    <CheckBox Content="Check me" IsChecked="{Binding IsChecked}"/>
                    <TextBlock Text="{Binding Name1}"/>
                    <TextBlock Text="{Binding Name2}"/>
                </StackPanel>
            </DataTemplate>
        </ItemsControl.ItemTemplate>
    </ItemsControl>
</Window>

Code-behind for MainWindow:

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();

        DataContext = new MainViewModel
        {
            Items =
            {
                // these are samle items;
                // you can fill collection the way you want
                new ItemViewModel { Name1 = "A", Name2 = "B" },
                new ItemViewModel { Name1 = "C", Name2 = "D" },
                new ItemViewModel { Name1 = "E", Name2 = "F" },
            }
        };
    }
}

In case of UserControl you must to provide appropriate properties from your control to bind to, and change ItemTemplate.

Answer 2

Non-MVVM way

To access your value inside your customized UserControl. You need a UserControl with a name on every control in it and then when you use, you just call it's name.

In MyUserControl.xaml:

<Stackpanel x:name="panel1">
   <Checkbox x:name="checkbox1" height="10" width="10"/> <!-- Apply your style here -->
   <Textblock x:name="name1" text="a"/>
   <Textblock x:name="name2" text="b"/>
   <Textblock x:name="name3" text="c"/>
</Stackpanel>

In MyWindow.xaml:

<local:MyUserControl x:Name="myUserControlInstance"/>
<Button Content="Click me" Click="Button_Click" />

In MyWindow.cs:

    private void Button_Click(object sender, RoutedEventArgs e) 
    {
        if (myUserControlInstance.checkbox1.IsChecked.HasValue)
        {
             var checkboxValue=myUserControlInstance.checkbox1.IsChecked.Value;
        }
    }