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Calibrun.Micro Sample/Feature/UWP : What is "cm:Bind.Model="{Binding}"

Here is Calibrun.Micro example with UWP.
in Bubbling sample, in this file,
there is this line
<Grid cm:Bind.Model="{Binding}">
What is mean ? Why does it necessary ?
I thought Next line is enough for send $dataContext
<Button x:Name="Message" cm:Message.Attach="SelectPhrase($dataContext)" Margin="0,12" />
Please advice me....

Let's analyze the code as quite some things are a bit obscure in Caliburn.Micro as it works through convention:
<Page
x:Class="Features.CrossPlatform.Views.BubblingView"
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:cm="using:Caliburn.Micro"
mc:Ignorable="d">
<StackPanel Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<TextBlock Text="actions" Style="{StaticResource SubheaderTextBlockStyle}" Margin="40,10,40,0"/>
<StackPanel Margin="40,20">
<ItemsControl x:Name="Phrases">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Grid cm:Bind.Model="{Binding}">
<Button x:Name="Message" cm:Message.Attach="SelectPhrase($dataContext)" Margin="0,12" />
</Grid>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</StackPanel>
</Page>
First of all, the page's datacontext (viewmodel) is set through naming convetion. This viewmodel can be found here. As you can see, this viewmodel has a Phrases property and a SelectPhrase(MessageActivityViewModel phrase) method.
If we go down the tree, we have an <ItemsControl x:Name="Phrases"> which binds to the Phrases property, which is a collection of MessageActivityViewModel.
An ItemsControl needs a way to present the items, which is defined in the DataTemplate. This template has a Grid as root object. If the Grid would not use {Binding}, it would inherit the datacontext from the template, which is the current element being rendered (a single MessageActivityViewModel). However, we want to call the SelectPhrase method on the BubblingViewModel and not on the MessageActivityViewModel. To be able to do that, we use {Binding} to tell the Grid binds to the page's viewmodel instead of to the single rendered MessageActivityViewModel.
What the Button does, is sending the datacontext object (being the rendered MessageActivityViewModel item) back to your viewmodel.
$dataContext:
Passes the DataContext of the element that the ActionMessage is attached to. This is very useful in Master/Detail scenarios where the ActionMessage may bubble to a parent VM but needs to carry with it the child instance to be acted upon.
Source: http://caliburnmicro.com/documentation/cheat-sheet

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>

Bind button in DataTemplate to command in the form's ViewModel

My problem is similar to the one described in this question:
WPF MVVM Button Control Binding in DataTemplate
Here is my XAML:
<Window x:Class="MissileSharp.Launcher.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MissileSharp Launcher" Height="350" Width="525">
<Grid>
<!-- when I put the button here (outside the list), the binding works -->
<!--<Button Content="test" Command="{Binding Path=FireCommand}" />-->
<ListBox ItemsSource="{Binding CommandSets}">
<ListBox.ItemTemplate>
<DataTemplate>
<!-- I need the button here (inside the list), and here the binding does NOT work -->
<Button Content="{Binding}" Command="{Binding Path=FireCommand}" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Window>
It's just a ListBox, bound to an ObservableCollection<string> named CommandSets (which is in the ViewModel).
This binding works (it displays a button for each item in the collection).
Now I want to bind the button to a command (FireCommand), which is also in the ViewModel.
Here's the relevant part of the ViewModel:
public class MainWindowViewModel : INotifyPropertyChanged
{
public ICommand FireCommand { get; set; }
public ObservableCollection<string> CommandSets { get; set; }
public MainWindowViewModel()
{
this.FireCommand = new RelayCommand(new Action<object>(this.FireMissile));
}
private void FireMissile(Object obj)
{
System.Windows.MessageBox.Show("fire");
}
}
The binding of this button does NOT work.
From what I've understood from the question I linked above, the binding doesn't work because:
(correct me if I'm wrong)
The button is inside the ListBox, so it only "knows" the binding of the ListBox (the ObservableCollection, in this case), but not the binding of the main window
I'm trying to bind to a command in the main ViewModel of the main window (which the button doesn't "know")
The command itself is definitely correct, because when I put the button outside the ListBox (see the XAML above for an example), the binding works and the command is executed.
Apparently, I "just" need to tell the button to bind to the main ViewModel of the form.
But I'm not able to figure out the right XAML syntax.
I tried several approaches that I found after some googling, but none of them worked for me:
<Button Content="{Binding}" Command="{Binding RelativeSource={RelativeSource Window}, Path=DataContext.FireCommand}" />
<Button Content="{Binding}" Command="{Binding Path=FireCommand, Source={StaticResource MainWindow}}" />
<Button Content="{Binding}" Command="{Binding Path=FireCommand, RelativeSource={RelativeSource AncestorType={x:Type Window}}}" />
Could someone please:
give me the proper XAML to bind the button inside the ListBox to a command in the form's MainViewModel?
point me to a link where this advanced binding stuff is explained in a way that a WPF/MVVM beginner can understand?
I'm feeling like I'm just copying and pasting arcane XAML incantations, and so far I don't have any clue (and can't find any good documentation) how I would figure out by myself in which cases I'd need RelativeSource or StaticResource or whatever instead of a "normal" binding.

It's:
{Binding DataContext.FireCommand,
RelativeSource={RelativeSource AncestorType=ListBox}}
No need to walk up to the root unless you actually change the DataContext along the way, but as the ListBox seems to bind to a property on the main VM this should be enough.
The only thing i recommend reading is the Data Binding Overview, and the Binding class documentation (including its properties).
Also here is a short explanation on how bindings are constructed: A binding consists of a source and a Path relative to that source, by default the source is the current DataContext. Sources that can be set explicitly are: Source, ElementName & RelativeSource. Setting any of those will override the DataContext as source.
So if you use a source like RelativeSource and want to access something in the DataContext on that level the DataContext needs to appear in the Path.

This may be considered unrelated by most, but this search is only 1 of 3 results that you'll find searching for data binding commands to controls inside a data template--as it relates to Xamarin Forms. So, maybe it'll help someone now-a-days.
Like me you may wonder how to bind commands inside a BindableLayout. Credit jesulink2514 for answering this at Xamarin Forums, where it's probably overlooked by many because of all the comments. Here's his solution, but I'm including the link below:
<ContenPage x:Name="MainPage">
<ListView Grid.Row="1"
ItemsSource="{Binding Customers}"
VerticalOptions="Fill"
x:Name="ListviewCustomer">
<ListView.ItemTemplate>
<DataTemplate>
<Label Text="{Binding Property}"/>
<Button Command="{Binding BindingContext.ItemCommand, Source={x:Reference MainPage}}"
CommandParameter="{Binding .}">Click me</Button>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</ContentPage>
https://forums.xamarin.com/discussion/comment/217355/#Comment_217355

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).

Use of DataTemplate

I'm quite new to C# and Windows Phone 7 for that sake, but none the less, I've thrown myself into trying to make a small app for myself. Here's my problem:
I'm trying to set up a DataTemplate that will position my Name and Drinks variables that I've declared in MainPage.xaml.cs. Here's my action when button1 is clicked:
private void button1_Click(object sender, RoutedEventArgs e)
{
string Name = participantName.Text;
int Drinks = 0;
listBox1.Items.Add(Name + Drinks);
}
And here is my DataTemplate from MainPage.xaml
<ListBox Height="Auto" HorizontalAlignment="Stretch" Margin="7,74,0,0" Name="listBox1" VerticalAlignment="Stretch" Width="Auto">
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Height="132">
<TextBlock Text="{Binding Path=Name}" FontSize="35" />
<StackPanel Width="370">
<TextBlock Text="{Binding Path=Drinks}" FontSize="35" />
</StackPanel>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
The problem is that my data is not shown. It works perfectly without the DataTemplate, but as soon as I use it, my text simply doesn't get through. Your help is very much appreciated.

The template itself is ok. The bindings on the template, though, are currently incorrect.
When you add a new item to the list box, you are just adding a plain old string (which is currently missing a space, BTW.) Your bindings, though, expect the object in the list to have a Name property and a Drinks property, which of course the string class does not have.
The usual solution here is to logically separate your data model from your presentation, by creating a class to store the data itself (probably PersonDrink, with the appropriate Name and Drinks properties) and then adding those objects to the list.
You should read up on the MVVM pattern, as it provides an excellent way to ensure that changes in your data are reflected in your view, and visa versa.

http://amarchandra.wordpress.com/2011/12/18/binding-multiple-object-in-wp7-using-listbox/
Here is a sample for binding data using a datatemplate. I hope this might help you.