I am developing a WPF application using MVVM. Inside the window, I have a control that inherits from UserControl, which allows me to call it a DetailView.
DetailView is tied to a property in VM (CurrentDetail), which can be of different types: UserDetail, AccountDetail, CalendarDetail, etc. All inherit from the same class.
I have a "ThumbnailBar" in which I can navigate between various detailed instances that have already been opened, imagine AccountDetail1, AccountDetail2, etc.
This navigation handles the CurrentDetail update in the virtual machine and the OnPropertyChanged event
The problem occurs when I switch from one type (e.g. AccontDetail3) to another type (UserDetail6). I noticed that it fires the Unloaded event of the control that I'm leaving, and the control that I'm going to initialize, both things don't happen when I move through an instance of the same type
This causes some problems, for example, in a calendar where I have a telerik RadScheduler, which will not save the date that I switched to and rebooted with today's date.
I know, and I already tested, I could save the SelectecTimeSlot variable and continue to reload it, but it will be just a patch
EDIT - some code:
Here is MainView.xaml where I call CurrentDetailsWorkSpace
<Border x:Name="BorderExteriorContent" BorderBrush="Transparent" BorderThickness="0" Grid.Column="1" Grid.Row="1" Grid.ColumnSpan="2"> <ContentControl x:Name="DetalleContenidoWrkSpc" Background="Red" Height="{Binding ElementName=BorderExteriorContent,Path=ActualHeight}" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" Content="{Binding CurrentDetailsWorkSpace}" VerticalAlignment="Top" Panel.ZIndex="1" /> </Border>
And here is CalendarView (one of the views that is unloaded) and yes I use DataTemplates
<base:BaseUCView xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:base="clr-namespace:MRWTINT.HGC.Win.Views.Base" mc:Ignorable="d" xmlns:calVm="clr-namespace:MRWTINT.HGC.Win.ViewModels.Calendario" x:Class="MRWTINT.HGC.Win.Views.Calendario.CalendarioView" xmlns:draganddrop="clr-namespace:MRWTINT.HGC.Win.ViewModels.DragDropLib" xmlns:Calendario="clr-namespace:MRWTINT.HGC.Win.Themes.Calendario" Margin="0" d:DesignWidth="730" Height="Auto" Unloaded="BaseUcViewUnloaded"> <Border x:Name="border" Margin="0,0,30,0" BorderBrush="#FF8A8A8A" BorderThickness="1" CornerRadius="3" RenderTransformOrigin="0.5,0.5"> <Border.RenderTransform> <TransformGroup> <ScaleTransform/> <SkewTransform/> <RotateTransform/> <TranslateTransform/> </TransformGroup> </Border.RenderTransform> <Grid > <Grid Background="White" Grid.IsSharedSizeScope="True"> <Grid.Resources> <DataTemplate x:Key="DayWeekSlotTemplate"> <Border Background="Black" Opacity="0.1" MinHeight="20" MinWidth="800" /> </DataTemplate> <DataTemplate x:Key="AllDaySlotTemplate"> <Border Background="Black" Opacity="0.1" MinHeight="44" MinWidth="800" /> </DataTemplate> <DataTemplate x:Key="MonthSlotTemplate"> <Border Background="Black" Opacity="0.1" MinHeight="120" MinWidth="120" /> </DataTemplate> <DataTemplate x:Key="TimeLineSlotTemplate"> <Border Background="Black" Opacity="0.1" MinHeight="800" MinWidth="110" /> </DataTemplate> <Calendario:TimeSlotTemplateSelector x:Key="TimeSlotTemplateSelector" MonthSlotTemplate="{StaticResource MonthSlotTemplate}" TimeLineSlotTemplate="{StaticResource TimeLineSlotTemplate}" AllDaySlotTemplate="{StaticResource AllDaySlotTemplate}" DayWeekSlotTemplate="{StaticResource DayWeekSlotTemplate}" /> </Grid.Resources> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="*"/> </Grid.RowDefinitions> <telerik:RadBusyIndicator x:Name="busyIndicator" Grid.Row="1" BusyContent="{DynamicResource LBL_DetalleCalendario}" IsBusy="{Binding IsBusy}" Background="{x:Null}" BorderBrush="{x:Null}" DisplayAfter="{Binding BusyIndicatorDelayedDisplay}"> <telerik:RadScheduler x:Name="scheduler" TimeSlotTemplateSelector="{StaticResource TimeSlotTemplateSelector}" draganddrop:DragDropHelper.IsDropTarget="true" Margin="0" Grid.Row="1" FirstDayOfWeek="Monday" FontFamily="Arial" FontSize="10.667" AppointmentsSource="{Binding ActividadesView}" calVm:CalendarioEventBehaviours.CalendarioCreateActividadCommand="{Binding SaveCommand}" calVm:CalendarioEventBehaviours.CalendarioAddActividadCommand="{Binding AddNewActividadCommand}" calVm:CalendarioEventBehaviours.CalendarioDeleteActividadCommand="{Binding DeleteActividadCommand}" calVm:CalendarioEventBehaviours.CalendarioEditingActividadCommand="{Binding EditingActividadCommand}" calVm:CalendarioEventBehaviours.CalendarioEditedActividadCommand="{Binding EditedActividadCommand}" telerik:StyleManager.Theme="{DynamicResource RadSchedulerTheme}" ToolTip="{DynamicResource LBL_ToolTip_Calendario_Generico}" VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch" ShowsConfirmationWindowOnDelete="False" OpenModalDialogs="True" Height="Auto" AllDayAreaHeight="0" ViewMode="{Binding CalendarioViewMode, Mode=OneWayToSource}"> <telerik:RadScheduler.MonthViewDefinition > <telerik:MonthViewDefinition /> </telerik:RadScheduler.MonthViewDefinition> <telerik:RadScheduler.DayViewDefinition > <telerik:DayViewDefinition DayStartTime="07:00:00" /> </telerik:RadScheduler.DayViewDefinition > <telerik:RadScheduler.TimelineViewDefinition > <telerik:TimelineViewDefinition DayStartTime="07:00:00" /> </telerik:RadScheduler.TimelineViewDefinition> <telerik:RadScheduler.RenderTransform > <TransformGroup > <ScaleTransform/> <SkewTransform/> <RotateTransform/> <TranslateTransform/> </TransformGroup> </telerik:RadScheduler.RenderTransform> <telerik:RadScheduler.WeekViewDefinition > <telerik:WeekViewDefinition DayStartTime="07:00:00" /> </telerik:RadScheduler.WeekViewDefinition> <VisualStateManager.CustomVisualStateManager> <VisualStateManager /> </VisualStateManager.CustomVisualStateManager> </telerik:RadScheduler> </telerik:RadBusyIndicator> <Grid x:Name="Botonera" Margin="10,4,0,0" RenderTransformOrigin="0.5,0.5" Grid.Column="0" HorizontalAlignment="Left" VerticalAlignment="Top"> <Grid.ColumnDefinitions> <ColumnDefinition /> </Grid.ColumnDefinitions> <Grid.RowDefinitions> <RowDefinition/> </Grid.RowDefinitions> <StackPanel Grid.Column="0" x:Name="PanelRefresh" Orientation="Horizontal" Cursor="Hand"> <Image x:Name="imgResfresh" Width="16" Height="16" Source="..\..\Resources\Calendario\table_refresh.png" /> <Button x:Name="btnRefresh" Content="{DynamicResource BTN_Refrescar}" Style="{StaticResource ButtonStyle}" Background="{x:Null}" FontFamily="Arial" FontSize="10.667" Margin="0,0,5,0" Command="{Binding RefreshCommand}" /> <Image x:Name="imgWeekends" Margin="10,0,0,0" Width="16" Height="16" Source="..\..\Resources\Calendario\table_row_delete.png" /> <Button x:Name="btnWeekends" Style="{StaticResource ButtonStyle}" Background="{x:Null}" FontFamily="Arial" FontSize="10.667" Margin="0,0,5,0" Command="{Binding RefreshCommand}" /> </StackPanel> </Grid> </Grid> </Grid> </Border>
Here's an excerpt from AccountView, where I also use DataTemplates
<DataTemplate x:Key="ImgContactoTemplate"> <Image RenderOptions.BitmapScalingMode="NearestNeighbor" Width="16" Height="16" Margin="0,1,0,0" Source="pack://application:,,,/Resources/Cuentas/user.png" /> </DataTemplate> <DataTemplate x:Key="ImgOportunidadTemplate"> <Image x:Name="imgTipoOportunidadEtapa" Width="16" Height="16" RenderOptions.BitmapScalingMode="NearestNeighbor" Source="{Binding IDTipoEtapa, Converter={StaticResource valueToImageConverter}, ConverterParameter=EtapaOportunidadMini}" VerticalAlignment="Center" HorizontalAlignment="Center" /> </DataTemplate> <DataTemplate x:Key="BtCellDataTemplate"> <Button x:Name="btnNewActivityFromOportunidad" Margin="0" Width="20" Height="20" Background="Transparent" Cursor="Hand" Command="Cuentas:CuentaViewModel.NewActivityFromOportunidadCommand" CommandParameter="{Binding IDOportunidad}" Padding="0" VerticalAlignment="Center" HorizontalAlignment="Center" Visibility="{Binding CanUserCreateNew}" Style="{DynamicResource ButtonStyle}"> <Image RenderOptions.BitmapScalingMode="NearestNeighbor" Width="16" Height="16" Margin="0" Source="pack://application:,,,/Resources/Calendario/calendar_add.png" /> </Button> </DataTemplate>
So, using different DataTemplates for each type leads to unloading, what makes sense, any idea to solve this problem?
EDIT - I have a DataTemplates.xaml with a DataTemplate for each type in a ResourceDictionary , for example:
<DataTemplate DataType="{x:Type vmCal:CalendarioBusquedaViewModel}"> <viewsCalendario:CalendarioBusquedaView Width="Auto" MaxWidth="Infinity"/> </DataTemplate>
Related posts I already read: In wpf, is there a way to execute the code before the control is unloaded ...? for example, an unload event? How to save control state in tabs in TabControl