Develop Reference

ItemSource of Listbox is not updated on item change

In my WPF application I have ListBox which contains a collection of items. One item can be added when a button is clicked and it is selected in the opened dialogue. As soon as a item is selected the dialogue closes and the item's image and name should be displayed in my ListBox. Unfortunately the Listbox does not update and nothing changes.
Usercontrol with Listbox:
<ListBox ItemsSource="{Binding BlButtonCollection, UpdateSourceTrigger=PropertyChanged}" VerticalContentAlignment="Stretch" SelectedItem="{Binding SelectedSticker}"
HorizontalContentAlignment="Stretch" ItemContainerStyle="{StaticResource ListBoxItemStyle}">
<ListBox.Resources>
<viewmodels1:BindingProxy x:Key="ProxyElement" Data="{Binding}" />
</ListBox.Resources>
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<UniformGrid Columns="4" Rows="10"/>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Border BorderBrush="Black" BorderThickness="1">
<Grid x:Name="f">
<Grid.RowDefinitions>
<RowDefinition Height="5*"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Button x:Name="btnSelectArticle" Background="Transparent" Grid.RowSpan="2" BorderThickness="0"
Command="{Binding DataContext.ButtonClicked,RelativeSource={RelativeSource Mode=FindAncestor,AncestorType={x:Type ListBox}}}"/>
<Image Height="1.5cm" HorizontalAlignment="Center" Source="{Binding ItemImage.ImageUrl, Converter={StaticResource ImageFormatConverter}}"/>
<TextBlock Text="{Binding ItemName}" Width="4cm" Height="0.8cm" TextWrapping="Wrap" Grid.Row="1" HorizontalAlignment="Center"/>
</Grid>
</Border>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Controls with ListBoxes in main window:
<formats:OneXTwo x:Name="oneXTwo" BlButtonCollection="{Binding BlButtons_2}" IsBlVisible="Visible" Visibility="{Binding Are2StickersVisible}"
ButtonClicked="{Binding BlStickerButtonClickedCommand}"/>
<formats:ThreeXEight x:Name="threeXEight" BlButtonCollection="{Binding BlButtons_24}" IsBlVisible="Visible" Visibility="{Binding Are24StickersVisible}"
ButtonClicked="{Binding BlStickerButtonClickedCommand}"/>
<formats:FourXTen x:Name="fourXTen" BlButtonCollection="{Binding BlButtons_40, Mode=OneWay, UpdateSourceTrigger=PropertyChanged}" IsBlVisible="Visible" Visibility="{Binding Are40StickersVisible}"
ButtonClicked="{Binding BlStickerButtonClickedCommand}" SelectedSticker="{Binding SelectedBlSticker, Mode=TwoWay}" />
I should mention that I have three different formats and each format is a own user-control. Therfore, they are displayed in a shell-view and based on a ComboBox selection one format is displayed. If I am running the application, select a image nothing happens, but if I change the bound value of the textblock in the list view and switch it back to 'Itemname' the Image and Name are displayed.

Have you set the DataContext to a specific ViewModel?
ObservableCollection can only ensure the add/remove operation for items that can be updated to the UI. If you want to the item property to notify the UI, you should override the setter of the property and implement INotifyPropertyChanged.

UWP: ListView ItemClick not work

I have to do a Master/Detail in UWP
1- If you're in Laptop:
The responsible GridView of show the data of this person appear.
So when you select a item is binded to ViewModel.
<ScrollViewer x:Name="ScrollLista" Grid.Column="0" Grid.Row="1">
<ListView x:Name="Lista" ItemsSource="{Binding Lista}" ItemClick="Lista_ItemClick" SelectedItem="{Binding PersonaSeleccionada, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
<ListView.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding nombre}" />
<TextBlock Text="{Binding apellido}" />
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ScrollViewer>
<Grid x:Name="CRUD" Grid.Column="1" Grid.Row="1" DataContext="{Binding PersonaSeleccionada}" Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
...
</Grid>
2- When is a mobile:
Only will appear the list and when I select a item this should be two things.
Call to ViewModel by binding using SelectedItem.
Call to code behind using ItemClick, this will be in charge of calling another page.
The problem: ItemClick not working, not call to Lista_ItemClick... How can I call a method and send the item selected to code behind?

For click event to work, IsItemClickEnabled="True" should be added to the ListView.

Combobox not showing groupings

I'm trying to organize the items in a combobox into groups. To do this I've created an object that has project and group name strings. I then set the GroupStyle and ItemTemplate to display these values. However, Currently, only the project string is displayed in the combobox (and the box has a red border, indicating some kind of error).
Here's the xaml for my combobox:
<ComboBox x:Name="comboBoxProjects" Margin="165,90,28,0" Grid.Column="0" VerticalAlignment="Top" Height="25"
IsSynchronizedWithCurrentItem="True" SelectedIndex="0" Style="{StaticResource ComboBoxDefault}"
ItemsSource="{Binding Path=ProjectClientSelections.ProjectGroupItems,Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
SelectedItem="{Binding Path=ProjectClientSelections.SelectedProject, UpdateSourceTrigger=PropertyChanged}">
<ComboBox.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<TextBlock Text="{Binding GroupName}"/>
</DataTemplate>
</GroupStyle.HeaderTemplate>
</GroupStyle>
</ComboBox.GroupStyle>
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Project}"/>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
Does anyone see where I'm going wrong?

In GroupStyle, the DataContext is not your item (the type contained in your ItemsSource), but a CollectionViewGroup object, which is formed based on the collection of items that you have grouped. Because of this you have to declare a binding path to one of the properties in CollectionViewGroup, for example, based on your code you probably want to use Name property. See MSDN CollectionViewGroup Class
Change your GroupStyle.HeaderTemplate to this:
<DataTemplate>
<TextBlock Text="{Binding Name}" />
</DataTemplate>
You don't show how you have formed your GroupDescriptions. If you have not grouped the items already, you can do it in following way (assuming the XAML you have provided is contained inside Window and Window's and GroupBox's DataContext is the same):
<Window.Resources>
<CollectionViewSource
Source="{Binding ProjectClientSelections.ProjectGroupItems}"
x:Key="GroupedProjectItems">
<CollectionViewSource.GroupDescriptions>
<PropertyGroupDescription
PropertyName="GroupName" />
</CollectionViewSource.GroupDescriptions>
</CollectionViewSource>
</Window.Resources>
After this change GroupBox ItemSource binding to the following (directly to CollectionViewSource resource):
ItemsSource="{Binding Source={StaticResource GroupedProjectItems}}"

Unable to find selected index in ListView for windows phone

I am facing a trouble in getting item's index in Listview. I have a child element inside data template like the following:
<ListView x:Name="ptype_gw" Width="300" HorizontalAlignment="Left" ItemsSource="{Binding PropertyTypes}" >
<ListView.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<TextBlock Text="{Binding title}" Style="{ThemeResource menu_heading_green}" Grid.Row="0" />
<GridView Grid.Row="1" ItemsSource="{Binding childs}" >
<GridView.ItemTemplate>
<DataTemplate>
<Grid>
<RadioButton Name="PropertyTypeRadio" Content="{Binding title}" Tag="{Binding}" GroupName="Types" Checked="RadioButton_Checked" Background="White" Foreground="Black" BorderBrush="Black" />
</Grid>
</DataTemplate>
</GridView.ItemTemplate>
</GridView>
</Grid>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
Now i Need to get the index of selected item whenever radio button is checked. I have tried the following code:
var item = (sender as FrameworkElement).DataContext;
int index = ptype_gw.Items.IndexOf(item);
But it didn't helped me.

That’s very simple.
Bind the SelectedItem of list to a property in view model. Say SelectedItem. When user selects an item, the SelectedItem property will hold the details of current selected item.
Now handle the radio button checked or unchecked event as per your requirement. When the event occurs, check the SelectedItem property.
I am talking about MVVM case.
If you are writing code in your xaml.cs itself, then get the selected property of listbox directly like this in the radio button checked event.
ListBoxName.SelectedItem
ListBoxName.SelectedIndex

How do I change the layout of a Grid bound inside another?

I have a Grid inside a ListBox bound to a list of items. When I press a global 'edit' button, I want a series of checkboxes to appear in the Grid. I was planning on doing this in a similar fashion to how orientation change is handled, however I can't figure out how to access the bound grid to change the column properties
Here's my XAML:
<ListBox ItemsSource="{Binding Path=Items}">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="1"></ColumnDefinition>
<ColumnDefinition Width="50"></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<CheckBox
Grid.Column="0"
Grid.ColumnSpan="1"
IsChecked="{Binding IsSelected, Mode=TwoWay}">
</CheckBox>
<TextBlock
Grid.Column="0"
Grid.ColumnSpan="3"
Text="{Binding ItemName}">
</TextBlock>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
I was going to set the CheckBox and TextBlock ColumnSpan to 2 on edit mode, then back to 1/3 on cancel. But I can't access those.
Is there a smarter way to do this?
I also considered setting visibility on the Checkbox to a bound value, but this will mean the grid will still have a gap when not in edit mode.