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Im creating ViewModels from MainViewModel, how can i connect View to my ViewModel [duplicate]

When I define a DataTemplate inline, Visual Studio knows about the type I'm binding to, and properties in that type come up in autocomplete (for example in the code below I was able to select DisplayName from the autocomplete list inside the FirstViewModel template).
<DataTemplate DataType="{x:Type viewmodels:FirstViewModel}">
<StackPanel >
<Label Content="{Binding DisplayName}"/>
</StackPanel>
</DataTemplate>
<DataTemplate DataType="{x:Type viewmodels:SecondViewModel}">
<views:SecondView/>
</DataTemplate>
However, when the data template references an external control, as for SecondViewModel in the code above, when I'm in the file for the SecondView usercontrol, since it's just a control, the type isn't bound and the editor doesn't help me with anything.
I've tried wrapping my whole control (inside the UserControl element) in the same DataTemplate tag, but then my whole view just shows "System.Windows.DataTemplate".
<UserControl x:Class="Gui.Views.Tabs.ExamsTabViews.ExamInfoView"
xmlns:vm="clr-namespace:Gui.ViewModels"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800">
<DataTemplate DataType="vm:ExamInfoViewModel">
<DockPanel VerticalAlignment="Stretch" HorizontalAlignment="Stretch">
<!-- contents of the template -->
</DockPanel>
</DataTemplate>
</UserControl>
Is there a way to achieve this kind of binding for the editor?

<DataTemplate DataType="{x:Type viewmodels:SecondViewModel}">
<views:SecondView/>
</DataTemplate>
when this DataTemplate is instantiated, there will be created SecondView and that SecondView will have a SecondViewModel in DataContext. So there is no need any DataTemplate in SecondViewModel control - bind to DataContext instead ({Binding SecondViewModelProperty}). To have design-time support for such binding use d:DataContext="{d:DesignInstance}:
<UserControl d:DataContext="{d:DesignInstance Type=vm:ExamInfoViewModel,
IsDesignTimeCreatable=True}" ...>

Command- and InputBindings in a DataTemplate

I have a WPF UserControl that I'm trying to adapt to my program with kind of a MVVM pattern. Now the problem is, that the UserControl uses Command- and InputBindings which I can't simply apply to a DataTemplate. What options do I have to implement the same functionality without even having a code-behind?
Here's the XAML as of right now:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:MyProject.Settings"
xmlns:elements="clr-namespace:MyProject.Settings.Elements"
xmlns:xctk="http://schemas.xceed.com/wpf/xaml/toolkit"
xmlns:dataPresenter="http://infragistics.com/DataPresenter"
xmlns:igEditors="http://infragistics.com/Editors"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity">
<DataTemplate x:Key="PrioritySettingTemplate" DataType="{x:Type elements:PrioritySetting}">
<ContentPresenter>
<ContentPresenter.InputBindings>
<KeyBinding Gesture="Delete" Key="Delete"
Command="{Binding TestCommand}" />
</ContentPresenter.InputBindings>
<ContentPresenter.ContentTemplate>
<DataTemplate DataType="{x:Type elements:PrioritySetting}">
<!--
Main part of the UserControl
-->
</DataTemplate>
</ContentPresenter.ContentTemplate>
</ContentPresenter>
</DataTemplate>

Master Detail MVVM with Prism and XAML binding view in data context

I have the following dummy application where I'm trying to build a Master Detail with two views. The first is the collection view, which I can successfully select an element of and it displays in the Content Presenter Data Template with the TextBlock and TextBox defined as they are below.
I have tried to Move the TextBlock and TextBox out to a view, but have been unsuccessful at getting it to display the data. If I remove the TBs and uncomment the view, it will display the view but the TBs in the view won't populate.
Of course, the idea is that I will have more than one type.
MainWindow
<Window x:Class="MyApp.Views.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:views="clr-namespace:MyApp.Views"
mc:Ignorable="d"
xmlns:prism="http://prismlibrary.com/"
xmlns:viewModel="clr-namespace:MyApp.ViewModels"
prism:ViewModelLocator.AutoWireViewModel="True"
Title="MainWindow" Height="350" Width="525">
<Grid x:Name="LayoutRoot">
<StackPanel Orientation="Horizontal">
<views:CollectionView DataContext="{Binding myItemCollection}">
</views:CollectionView>
<ContentPresenter x:Name="Detail" Content="{Binding myItemCollection.SelectedViewModel}">
<ContentPresenter.Resources>
<DataTemplate DataType="{x:Type viewModel:TextViewModel}">
<StackPanel>
<TextBlock Text="{Binding Name}"></TextBlock>
<TextBox Text="{Binding Text}"></TextBox>
<!--<views:TextView/>-->
</StackPanel>
</DataTemplate>
</ContentPresenter.Resources>
</ContentPresenter>
</StackPanel>
</Grid>
TextView
<UserControl x:Class="MyApp.Views.TextView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:MyApp.Views"
xmlns:viewModel="clr-namespace:MyApp.ViewModels"
mc:Ignorable="d"
xmlns:prism="http://prismlibrary.com/"
prism:ViewModelLocator.AutoWireViewModel="True"
d:DesignHeight="300" d:DesignWidth="300">
<Grid>
<StackPanel>
<TextBlock Text="Text Item"/>
<TextBlock Text="{Binding Name}"></TextBlock>
<TextBox Text="{Binding Text}"></TextBox>
</StackPanel>
</Grid>

You need to remove the prism:ViewModelLocator.AutoWireViewModel="True" attribute from your TextView.
What it does is it pulls the appropriate view model from the container and assigns the view model to TextView.DataContext. On the other hand in your template you do not explicitly pass the templated data to the TextView control, so it's expected to be inherited via automatic inheritance of DataContext. But that does not work, because TextView.DataContext is explicitly set by prism:ViewModelLocator.AutoWireViewModel="True".
In case it is required to use view model auto wiring you can always set this attribute from referencing scope, that is in XAML in which your view is "used", e.g.:
<StackPanel>
<views:TextView prism:ViewModelLocator.AutoWireViewModel="True" />
</StackPanel>

WPF MVVM error when relating View and ViewModel

I am learning to create an MVVM application following this tutorial, and it has this in its entrance view:
what worked in the example
<UserControl.Resources>
<DataTemplate DataType="{x:Type vm:ProductViewModel}">
<vw:ProductView />
</DataTemplate>
<DataTemplate DataType="{x:Type vm:SingleBrandViewModel}">
<vw:SingleBrandView />
</DataTemplate>
</UserControl.Resources>
so i tried the following in my code
what didn't work in my code
<Page x:Class="MvvmAttempt.FilesView"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:MvvmAttempt"
mc:Ignorable="d"
d:DesignHeight="300" d:DesignWidth="300"
Title="FilesView">
<Page.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="resources/Styles.xaml" />
</ResourceDictionary.MergedDictionaries>
<local:MySizeConverter x:Key="sizeConverter"/>
<DataTemplate DataType="{x:Type local:SingleFileView}"> <--- error here
<local:SingleFileViewModel/> <--- error here
</DataTemplate>
</ResourceDictionary>
</Page.Resources>
... other stuff ...
</Page>
x:Type has an underlining error message: The type 'x:Type' was not found. Verify that you are not missing an assembly reference and that all referenced assemblies have been built.
under <local:SingleFileViewModel/> , the error is: The specified value cannot be assigned. The following type was expected: "DependencyObject".
What could be causing the errors? Why did it expect DependencyObject when there isn't anything alike in the example code? Thanks!

Probably your mistake sits here:
<DataTemplate DataType="{x:Type local:SingleFileView}"> <--- error here
<local:SingleFileViewModel/> <--- error here
</DataTemplate>
Note, that you have specified ViewModel as the DataTemplate, and the View as the DataType of DataTemplate. So it seems to me that this should work:
<DataTemplate DataType="{x:Type local:SingleFileViewModel}">
<local:SingleFileView/>
</DataTemplate>

WPF Item Templates - TabControl

I am writing an application in which I utilize a tab control which will start with one tab open but allows the user to open multiple other tabs.
Each tab that is openned should have a treeview inside which I fill using databinding when the user loads a file.
I am new to WPF but I feel as if there is a way in which I can create a template containing each of the elements the TabItems should contain. How can I do this using templates? Right now my WPF for the tab items is the following
<TabItem Header="Survey 1">
<TreeView Height="461" Name="treeView1" VerticalAlignment="Top"
Width="625" Margin="0,0,6,0" ItemTemplateSelector="{StaticResource TreeviewDataSelector}" />
</TabItem>

I think you want something like this:
<Window x:Class="TestWpfApplication.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" Height="300" Width="300">
<Window.Resources>
<DataTemplate x:Key="TabItemTemplate">
<TreeView Height="461" Name="treeView1" VerticalAlignment="Top"
Width="625" Margin="0,0,6,0" ItemTemplateSelector="{StaticResource TreeviewDataSelector}" />
</DataTemplate>
</Window.Resources>
<Grid>
<TabControl ItemsSource="{Binding ListThatPowersTheTabs}"
ItemTemplate="{StaticResource TabItemTemplate}">
</TabControl>
</Grid>
You basically create re-usable templates as static resources which you refer to by their key name.

Usually in this sort of situation I bind my TabControl.ItemsSource to a ObservableCollect<ViewModelBase> OpenTabs, so my ViewModel is in charge of adding/removing new tabs as needed.
Then if you want something in every Tab, then overwrite the TabControl.ItemTemplate and use the following line to specify where to display the currently selected TabItem
<ContentControl Content="{Binding }" />
If you don't need to setup something in every single tab, you don't need to overwrite the TabControl.ItemTemplate - it will default to displaying the currently selected ViewModelBase in the Tab.
And I use DataTemplates to specify which View to use
<DataTemplate TargetType="{x:Type local:TabAViewModel}">
<local:TabAView />
</DataTemplate>
<DataTemplate TargetType="{x:Type local:TabBViewModel}">
<local:TabBView />
</DataTemplate>
<DataTemplate TargetType="{x:Type local:TabCViewModel}">
<local:TabCView />
</DataTemplate>