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UserControls not rendering

Okay, to start, I'm pretty inexperienced with WPF and XAML, so any pointers or advice would be greatly appreciated.
I have a scheduling program that I'm working on that I need some help setting up. I had things working previously, but it wasn't organized correctly. I had UI elements in my ViewModels that I would add to a StackPanel at the initialization of the MainWindow. Generally not MVVM style coding. So I made some views (UserControls) to display the things I have, and most everything broke.
Basically, I have a Schedule ViewModel that has some parameters and a list of a different Room ViewModels. Each Room ViewModel has a RoomSchedule ViewModel that contains a list of RoomEvent ViewModels.
I'm trying to write controls for the things that need displaying. I've created a Schedule view, which has a list box of Room views, and the Room view uses the RoomEvent view to display the events of the room. The Room view uses the WPF Extended Toolkit's TimelinePanel, the rest of the controls are pretty much basic controls. The general idea has been: a model provides data to the ViewModel, which massages that data to what needs to be displayed. So an Event should know how to display itself, a Room should know how to display itself, and the Schedule should know how to display itself.
The problem I'm running into is: now that I've scooted everything from the xaml.cs or ViewModel files to their appropriate places, the controls aren't rendering at all. I've been reading other SO postings where people have the same problem, but none of them seem to work for beginner stuff like this. I think I'm close, it seems like all the controls are being created, and the DataContext's are being set correctly, but nothing is showing up.
This is, basically, what I have so far. I left some of the xaml boilerplate stuff off for succinctness:
Schedule.xaml:
<StackPanel>
<ListBox ItemsSource="{Binding Rooms}" >
<ListBox.ItemTemplate>
<DataTemplate>
<localcontrols:RoomView ScheduleStart="{Binding ElementName=ScheduleControl, Path=DataContext.Start}"
</DataTemplate>
<ListBox.ItemTemplate>
</ListBox>
</StackPanel>
RoomView.xaml:
<extended:TimelinePanel BeginDate="{Binding localcontrols:ScheduleStart}" EndDate="{Binding localcontrols:ScheduleEnd}"
<ItemsControl ItemsSource="{Binding Path=mRoomSchedule.mScheduledEvents}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<localcontrols:EventView />
</DataTemplate>
</ItemsControls.ItemTemplate>
</ItemsControl>
</extended:TimelinePanel>
EventView.xaml:
<Border BorderThickness="1" BorderBrush="Black" extended:TimelinePanel.Date="{Binding mStartTime}" extended:TimelinePanel.DateEnd="{Binding mEndTime}">
<TextBlock Background="{Binding mColor}" Text="{Binding mEventID}" />
</Border>
The ScheduleStart and ScheduleEnd are dependency properties defined in RoomView.xaml.cs. My thinking was that Schedule would have Start and End properties that would be set in its constructor, and the RoomViews in the ListBox would bind to those properties to set the TimelinePanel's BeginDate and EndDate.

Maybe your bindings are wrong. When I need to bind to a dependency property I use the ElementName feature of binding to say which control I want and I give the root node a name, in this case Root. It's one way to solve it.
<UserControl
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:Weingartner.Controls"
x:Class="RoomView"
x:Name="Root">
<extended:TimelinePanel
BeginDate="{Binding ElementName=Root, Path=ScheduleStart}"
EndDate="{Binding ElementName=Root, Path=ScheduleEnd}"
>
<ItemsControl ItemsSource="{Binding Path=mRoomSchedule.mScheduledEvents}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<localcontrols:EventView />
</DataTemplate>
</ItemsControls.ItemTemplate>
</ItemsControl>
</extended:TimelinePanel>
</UserControl>

ItemClick event on part of GridView

I have a collection of objects that I want to bind to my Xaml (using a GridView at the moment). I don't know if a GridView is the best tool for what I want to achieve.
This is roughly my current DataTemplate:
I need a clicked/tapped trigger on Grid1. But when I use this template with a GridView, the ItemClick event will get triggered on the complete template - which is correct of course. How can I set an click event on Grid1? Can I add this event in my DataTemplate declaration?
That's basically the xaml for my GridView:
<GridView x:Name="RoomsGridView"
VerticalAlignment="Top"
ItemsSource="{Binding Rooms}"
ItemTemplate="{StaticResource RoomTemplate}"
SelectionMode="None"
IsSwipeEnabled="false"
IsItemClickEnabled="True"
ItemClick="RoomsGridView_ItemClick" Padding="0">
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</GridView.ItemsPanel>
</GridView>
Edit: I've found this sample but this seems only to work with Buttons!?

In the code you posted above you've told to GridView to capture item clicks via IsItemClickEnabled="True". You cannot have that option enabled if you want to be able to click on elements inside the DataTemplate.
I would suggest that you disable IsItemClickEnabled and instead add a click handler to your Grid1. Even better would be to substitute your Grid1 with a button that has custom styling. This would further allow you to bind the button to a command that you can control from your view model.

Disabling a TreeView item bound to an ItemsSource defined in xaml

I have a TreeView that I am binding to an ItemsSource that creates a CheckBox for each item. Here is the xaml:
<TreeView x:Name="ReasonTreeView" Height="Auto" Background="Transparent"
BorderThickness="0" IsTabStop="False"
ItemsSource="{Binding Path=AnswerOptions}">
<TreeView.ItemTemplate>
<HierarchicalDataTemplate DataType="{x:Type QSB:Answer}" ItemsSource="{Binding Path=AnswerOptions}">
<StackPanel Orientation="Horizontal">
<CheckBox Margin="0,5"
IsChecked="{Binding Path=IsSelected}"
IsEnabled="{Binding Path=Value,
Converter={StaticResource ReasonValueToEnabledConverter}}"
Visibility="{Binding Path=AnswerOptions,
Converter={StaticResource ParentNodeVisConverter}}" />
</StackPanel>
</HierarchicalDataTemplate>
</TreeView.ItemTemplate>
In my application I then create multiple instances of these. Depending on the instance of the TreeView, certain CheckBoxes need to be disabled so the user can not select them, however I'm uncertain of how I can access the individual items in the HierarchicalDataTemplate in the code.
After looking around for a while the only thing I can think of is to build the whole TreeView in the code behind instead of the xaml, but I would rather not have to resort to that. Is there anything else that I can do?
To help clarify my point and for illustrative purposes, this is essentially what I want to be able to do (in pseudocode): ReasonTreeView.ItemsSource[5].IsEnabled = false;
Which would disable the CheckBox (and any other controls in that HierarchicalDataTemplateItem) at index 5 of the TreeView's ItemsSource
Let me know if more information is needed

I meant that binding on the checkbox's isenabled property Path=Value. That Value member has to be bool and implement INotifyPropertyChanged then you can control IsEnabled from your model. Dont forget to add Mode=Twoway to your binding

Instead of accessing the CheckBox through Control.ItemsSource property you should make the change in your underlying collection (that is itemssource of your control). After making the change notify the View (your Control) that data has been changed so update the control.
Implement INotifyPropertyChanged in your underlying class and after changing the Property (which is responsible for Enabled/Disabled) value Notify the View.
If you are not familiar with concepts of Data Binding and INotifyPropertyChanged, I would suggest you to read some basic tutorials about it. It is one of the major feature of WPF which makes life very easy for doing things like yours

WPF implicit datatemplate with observablecollection

I'm new to WPF and using MVVM. I have a view in which I want to display different content according to what a user selects on a menu. One of those things is another user control Temp which has a view model (TempVM) so I am doing this:
<ContentControl Content="{Binding Path=TempVM}"/>
and TempVM (of type TempViewModel)is null until the user clicks a button. Its data template is this
<DataTemplate DataType="{x:Type vm:TempViewModel}">
<view:Temp />
</DataTemplate>
That's fine, but the other thing I want to do is show a listbox when a user clicks a different menu item. So I am trying to do
<ContentControl Content="{Binding Path=Missions}"/>
(Missions is an observable collection of MissionData) and trying to template it like this:
<DataTemplate DataType="{x:Type ObservableCollection(MissionData)}">
<StackPanel>
<ListBox ItemsSource="{Binding}" SelectedItem="{Binding Path=MissionData, Mode=TwoWay}" DisplayMemberPath="MissionName" SelectedValuePath="MissionId" />
<Button Content="Go"/>
</StackPanel>
</DataTemplate>
But the compiler doesn't like the type reference. If I try doing it by giving the template a key and specifying that key in the ContentControl it works but obviously I see the ListBox and button when there's no Missions. Obviously I could make a user control and viewmodel and follow the same pattern as I did for the TempVM but it seems over the top. Am I going the right way about this and what do I need to do?

From what i see is that you try to use a Collection as a dataobject which is in my opinion bad practice. Having a DataTemplate for a collection is also problematic, like you already have witnessed. I would advice you to use a ViewModel for your missions collection.
class MissionsSelectionViewModel
{
public ObservableCollection<Mission> Misssions;
public MissionData SelectedMission;
public ICommand MissionSelected;
}
and modify your datatemplate to
<DataTemplate DataType="{x:Type MissionsSelectionViewModel}">
<StackPanel>
<ListBox ItemsSource="{Binding Missions}" SelectedItem="{Binding Path=MissionData, Mode=TwoWay}" DisplayMemberPath="MissionName" SelectedValuePath="MissionId" />
<Button Content="Go" Command="{Binding MissionSelected}/>
</StackPanel>
</DataTemplate>

If I were to follow your pattern of implicit templates, I would derive a custom non-generic collection MissionDataCollection from ObservableCollection<MissionData> and use it to keep MissionData items. Then I would simply reference that collection in DataType. This solution gives other advantages like events aggregation over the collection that are useful.
However, it seems to me that the best solution is the following.
Add a IsMissionsListVisible property to your VM.
Bind the Visibility property of the ContentControl showing the list to the IsMissionsListVisible property.
Use a keyed DataTemplate resource.
Implement the logic that determines if IsMissionsListVisible. Supposedly it should be true when there is at least one mission in the selected item. But the logic may be more complex.
I would do it this way. In fact, I do it this way usually, and it gives several benefits. The most important is that I can explicitly control the logic of content visibility in various situations (e.g. async content refresh).

Control which field is displayed in the textbox part of a databound WPF ComboBox

I have a ComboBox in WPF which is databound, and has data template which controls how each of the items is displayed. I have made it so that each item is displayed with two bits of text (for the Name and Path properties) and one image (for the Icon property).
At the moment when I select an item from the ComboBox the textbox bit of the ComboBox just changes to say "TestWPF.Result" which is the name of the class which I have populated the ComboBox with.
I'm interested in one (or both) of two things:
How do I change it so that it displays the value of one of the fields there (eg. so it shows the value of the Name field rather than the name of the class)?
Is it possible get it to use the same DataTemplate there as in the list of items, so that once I have selected an item it displays in the closed ComboBox the same way as it looks in the list of items. Basically I've got a DataTemplate called ShowResults and a ComboBox which uses that template. I've also added in a separate ContentControl which I've got to show the details of the selected item in the ComboBox, but I want to get that to replace the textbox in the ComboBox.
Update:
Thanks for the first answer. I've tried using a separate ContentControl, as you've described, and it works fine. The question now is how to replace the textbox part of the ComboBox with this ContentControl. Any hints on that would be most welcome.
Also, is it possible to replace the textbox bit of the ComboBox control with a mixture of the ContentControl and a textbox, so that I can still type in the textbox to help select items from the ComboBox, but then when I close the dropdown the rest ContentControl bit will be populated with the rest of the text and the icon. Hope that makes sense - ask questions if it doesn't!
Code:
I've been asked to post my code - so here it is. I've tried to remove things that I know are definitely not relevant, but I'm not sure exactly what is relevant so when in doubt I've left things in.
<Window x:Class="TestWPF.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:custom="clr-namespace:TestWPF"
Title="Window1" Height="300" Width="843" Loaded="Window_Loaded">
<Window.Resources>
<DataTemplate x:Key="ShowResult" DataType="TestWPF.Result">
<StackPanel Margin="5" Orientation="Horizontal">
<Image Width="32" Height="32" Source="{Binding Path=Image}"/>
<StackPanel Margin="5">
<TextBlock FontWeight="Bold" Text="{Binding Path=Name}"/>
<TextBlock Text="{Binding Path=Path}"/>
</StackPanel>
</StackPanel>
</DataTemplate>
</Window.Resources>
<Grid Width="786">
<Button Height="23" HorizontalAlignment="Right" Margin="0,24,166,0" Name="btnTest" VerticalAlignment="Top" Width="75" Click="btnTest_Click">Add</Button>
<ComboBox StaysOpenOnEdit="True" DropDownClosed="comboBox1_DropDownClosed" PreviewTextInput="comboBox1_PreviewTextInput" SelectionChanged="comboBox1_SelectionChanged" ItemTemplate="{StaticResource ShowResult}" Margin="259,109,22,89" Name="comboBox1" IsEditable="True" />
<ContentControl Height="50" Margin="268,0,22,21" Name="contentControl1" VerticalAlignment="Bottom" Content="{Binding ElementName=comboBox1,Path=SelectedValue}" ContentTemplate="{StaticResource ShowResult}"/>
</Grid>

You got the binding part right - binding to the data and using a DataTemplate to display the source the way you want to.
As to your second question, a way to do it would be to use a ComboBox with IsEditable="True" as you have, and withing the TextChanged event handler check if the comboBox.Items contains the new value, if not check use Linq to seach for a match:
if (comboBox.Items.Contains(e.NewValue))
return;
var matches =
with comboBox.Items
select item
where item.BeginsWith(e.NewValue);
if (matches.Count > 0)
comboBox.SelectedItem = matches.First();

Just place the Property Binding expression to the textBox,You dont need to apply template.
Another way to get exact Data template, Place a ContentControl in the place of textBox and assign the same DataTemplate (say x:Name="robinTemplate")
<ContentControl Content="{Binding ElementName=cmbBox,Path=SelectedValue}" ContentTemplate="{StaticResource robinTemplate}"/>
For making the Selected content display in the same way :
Create a copy of the combobox control template and you will find a ContentPresenter there. Replace that with the ContentControl.. This is not the right solution though.