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Why this simple WPF command does not work?

I'm trying to add a WPF custom command to a control. What I've done:
XAML:
<Window x:Class="H.I.S.windows.CommandTest"
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:local="clr-namespace:H.I.S.windows"
mc:Ignorable="d"
Title="CommandTest" Height="450" Width="800">
<Window.CommandBindings>
<CommandBinding Command="local:CustomCommand.Save" CanExecute ="SaveCommand_CanExecute" Executed="SaveCommand_Executed" />
</Window.CommandBindings>
<Grid>
<Button Command="local:CustomCommand.Save" Height="50" Width="100">Click me!</Button>
</Grid>
</Window>
C#:
namespace H.I.S.windows
{
public partial class CommandTest : Window
{
public CommandTest()
{
InitializeComponent();
}
private void SaveCommand_CanExecute(object sender, CanExecuteRoutedEventArgs e)
{
e.CanExecute = true;
}
private void SaveCommand_Executed(object sender, ExecutedRoutedEventArgs e)
{
MessageBox.Show("Saved");
}
}
public static class CustomCommand
{
public static readonly RoutedUICommand Save = new RoutedUICommand(
"Save",
"Save",
typeof(CustomCommand),
new InputGestureCollection()
{
new KeyGesture(Key.F2)
}
);
}
}
The button is disabled (even in design mode) and doesn't let the user click on it.
I've just implemented codes described HERE.
Where I'm wrong?

The code what you have posted throws me an error because of this below statement,
<Window.CommandBindings>
<CommandBinding Command="local:CustomCommand.Save" CanExecute ="CommandBinding_CanExecute" Executed="CommandBinding_Executed" />
</Window.CommandBindings>
It started working for me after changing it to below,
<Window.CommandBindings>
<CommandBinding Command="local:CustomCommand.Save" CanExecute ="SaveCommand_CanExecute" Executed="SaveCommand_Executed" />
</Window.CommandBindings>
The event handlers in your code-behind are different from what you have in your xaml for CommandBinding.
"SaveCommand_CanExecute" and "SaveCommand_Executed"
After changing as above, it works for me and I can see the messagebox with "Saved" message when I hit click on it.
Hope you are not missing this. If something else stopping you then try to see if it shows any errors on further and let us know.

As #SirRufo suggested in question comments, Problem was that I declared "CommandBindings" for whole WPF window and button inside another control.
There are 2 solutions for this case:
1: Declaring CommandBindings for Button's direct parent.
2: Set name for control which is bound with command and add some code like below to control:
<Window ... x:Name = "windowName" ...>
<Window.CommandBindings>
<CommandBinding Command="custumCommand:CustomCommands.Save" CanExecute ="CommandBinding_CanExecute" Executed="CommandBinding_Executed" />
</Window.CommandBindings>
<Grid>
<StackPanel>
<GroupBox>
<Button Command="custumCommand:CustomCommands.Save" CommandTarget = "{Binding ElementName=windowName}" Content="Save" />
</GroupBox>
</StackPanel>
</Grid>
</Window>
Look at "CommandTarget" attribute of Button.

How to set WPF ApplicationCommands in code behind

I know how to set default ApplicationCommands commands in WPF in order to enable simple cut, copy, and paste operations via ContextMenu. However I need to be able to do this in the code behind so that I can assign the commands dynamically as my TextBoxes are created.
How can I recreate this very simple WPF code in the code behind:
<TextBox x:Name="txtTagName" Style="{StaticResource TextBoxStyle}">
<TextBox.ContextMenu>
<ContextMenu Style="{StaticResource DefaultContextMenuStyle}">
<MenuItem x:Name="cmCut" Header="Cut" Command="ApplicationCommands.Cut" />
<MenuItem x:Name="cmCopy" Header="Copy" Command="ApplicationCommands.Copy" />
<MenuItem x:Name="cmPaste" Header="Paste" Command="ApplicationCommands.Paste" />
</ContextMenu>
</TextBox.ContextMenu>
</TextBox>

you could do something like:
this.cmCut.Command = ApplicationCommands.Cut;

How can I recreate this very simple WPF code in the code behind
Something like this, i.e. you programmatically create an instance of a TextBox and a ContextMenu and set the same properties that you set in your XAML markup:
TextBox textBox = new TextBox();
textBox.Style = FindResource("TextBoxStyle") as Style;
ContextMenu cm = new ContextMenu();
cm.Style = FindResource("DefaultContextMenuStyle") as Style;
cm.Items.Add(new MenuItem() { Header = "Cut", Command = ApplicationCommands.Cut });
cm.Items.Add(new MenuItem() { Header = "Copy", Command = ApplicationCommands.Copy });
cm.Items.Add(new MenuItem() { Header = "Paste", Command = ApplicationCommands.Paste });
textBox.ContextMenu = cm;

Good answer found here: How do I add a custom routed command in WPF?
I wanted to add custom inputs with my own commands for MenuItems and with appropriate texts for the commands displayed in the MenuItems. What solved my problem was to add both a command binding and an input binding section for the window there I could bind my command class and input to that command:
<Window x:Class="SomeNamespace.MainWindow"
<!--Other stuff here-->
xmlns:local="clr-namespace:SomeNamespace"
mc:Ignorable="d"
Title="MainWindow" Height="544" Width="800">
<Window.CommandBindings>
<CommandBinding Command="local:Commands.SomeCommand" Executed="CommandBinding_SomeCommand" />
<CommandBinding Command="local:Commands.SomeOtherCommand" Executed="CommandBinding_SomeOtherCommand" />
</Window.CommandBindings>
<Window.InputBindings>
<KeyBinding Command="local:Commands.SomeCommand" Key="S" Modifiers="Ctrl" />
<KeyBinding Command="local:Commands.SomeOtherCommand" Key="O" Modifiers="Ctrl" />
</Window.InputBindings>
And then I could use it in my MenuItems like this (note that "InputGestureText" adds the shortcut/input text to the MenuItem):
<MenuItem Name="MenuItemSomeCommand" Command="local:Commands.SomeCommand" InputGestureText="Ctrl+S" />
<MenuItem Name="MenuItemSomeOtherCommand" Command="local:Commands.SomeOtherCommand" InputGestureText="Ctrl+O" />
Code for the "Commands" class (in my case in Commands.cs):
using System.Windows.Input;
namespace SomeNamespace
{
public static class Commands
{
public static readonly RoutedUICommand BuildFiles =
new RoutedUICommand("Some Command", "SomeCommand", typeof(MainWindow));
public static readonly RoutedUICommand BuildFiles =
new RoutedUICommand("Some Other Command", "SomeOtherCommand", typeof(MainWindow));
}
}
And code for the Executed binding command in MainWindow.xaml.cs:
public void CommandBinding_SomeCommand(Object sender, ExecutedRoutedEventArgs e)
{
// Add code that should trigger when the "SomeCommand" MenuItem is pressed
}
public void CommandBinding_SomeOtherCommand(Object sender, ExecutedRoutedEventArgs e)
{
// Add code that should trigger when the "SomeOtherCommand" MenuItem is pressed
}

How to show programmatically FocusVisualStyle?

Afters attemps I could tell that the FocusVisualStyle is only activated by the keyboard (tab and arrows keys).
Try to make the FocusVisualStyle to be applied after the component is loaded, it is impossible to do, There is an easy way to get around this problem?
I found this:
- focus visual not showing when navigating focus programically
- How do WPF buttons decide to show FocusVisualStyle?
- http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/99856840-f8ef-4547-9150-c4c46ec2f3df
But none shows a definite solution (without overwriting the component), and I could not write, can someone help?

I am not pretty sure I understand your issue, but I tried the example in one of the links and I was able to move focus to next component from code behind exactly as you would do using keyboard. Here is the code.
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525"
xmlns:local="clr-namespace:WpfApplication1" Loaded="OnLoaded"
>
<StackPanel Margin="10">
<TextBox Margin="10" x:Name="a" >A</TextBox>
<TextBox Margin="10" x:Name="b" >B</TextBox>
<Button Focusable="False" Click="OnClick">Move Focus</Button>
</StackPanel>
</Window>
public partial class MainWindow : Window {
public MainWindow() {
InitializeComponent();
}
private void OnLoaded(object sender, RoutedEventArgs e) {
a.Focus();
}
private void OnClick(object sender, RoutedEventArgs e) {
var request = new TraversalRequest(FocusNavigationDirection.Next);
var elementWithFocus = FocusManager.GetFocusedElement(FocusTest) as UIElement;
if (elementWithFocus != null)
elementWithFocus.MoveFocus(request);
}
}

Why isn't change button content working

I have this code:
private void ModifyButton_Click(object sender, RoutedEventArgs e)
{
ModifyButton.Content = "Another button name";
}
But it doesn't work. I mean, the modify button content doesn't change but the program doesn't fail or throw any exception.
I'm trying to modify the button name in order to change it's behavior (kinda Edit/Save) within the same button. Is this not possible using C#/WPF?
Thanks in advance.
EDIT:
XAML:
<Button Name="ModifyButton" Content="Modificar" Margin="5,10,0,0" Height="23" Width="120" HorizontalAlignment="Left" Click="ModifyButton_Click"></Button>
WEIRD BEHAVIOR: If I put a MessageBox.Show call after the change of the button content, then, while the message box is displayed the button dislay the new (changed) name, but after the message box is closed, then it shows it's original text.

I guess that the XAML of your UI is not bound to the value of your button. Did you check the DataBinding?
[EDIT]
Your magic information here is that you use ShowDialog(). As you already guessed, this influences your UI thread and therefore the display behavior. ShowDialog() displays the Form as a modal dialog and blocks your UI thread and therefore blocks the refresh of it. This may cause all sorts of weird behavior.

This is what i have and it works:
Window 1
<Window x:Class="WpfApplication1.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">
<Grid>
<Button Name="ModifyButton" Content="Open Dialog" Margin="80,104,78,0" Height="23" Click="ModifyButton_Click" VerticalAlignment="Top"></Button>
</Grid>
</Window>
public partial class Window1 : Window
{
public Window1()
{
InitializeComponent();
}
private void ModifyButton_Click(object sender, RoutedEventArgs e)
{
Window2 win2 = new Window2();
win2.ShowDialog();
}
}
Window 2
<Window x:Class="WpfApplication1.Window2"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window2" Height="300" Width="300">
<Grid>
<Button Name="ModifyButton" Content="Modificar" Margin="80,104,78,0" Height="23" Click="ModifyButton_Click" VerticalAlignment="Top"></Button>
</Grid>
</Window>
public partial class Window2 : Window
{
public Window2()
{
InitializeComponent();
}
private void ModifyButton_Click(object sender, RoutedEventArgs e)
{
ModifyButton.Content = "Another button name";
}
}

WPF MenuItem vs Button behavior in new window when mouse still down

I didn't know how to make the 'issue' (different behavior) more clear in the title, but I'll explain here.
In our WPF application, we're using the DataGrid control to list a number of entities. After double clicking a row, we open a new Window and in that Window, there are among other things a couple of MenuItem controls.
The problem is that when the Window opens on a position where one of the menu items is right under the mouse pointer, the menu item is actually clicked there at the mouse up of the double click.
When we use a button instead, the button click event is not fired automatically in the same situation.
We are now thinking about using buttons instead of menu items (or creating custom menus), but perhaps someone here has an explanation or solution to alter this behavior? Personally, I can't think of a case where this would be beneficial at all. Thanks in advance!
Example code is below. To see what I mean, double click the DataGrid row to open the new window and hold down the mouse button, move to the menu item and let the mouse button go (in TestWindow.xaml, exchange the MenuItem for a Button control to see the difference in behavior):
MainWindow.xaml
<Window x:Class="WpfApplication2.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<Style x:Key="DataGridRowStyle"
TargetType="{x:Type DataGridRow}">
<EventSetter Event="MouseDoubleClick" Handler="DataGridRow_MouseDoubleClick" />
</Style>
</Window.Resources>
<DataGrid RowStyle="{StaticResource DataGridRowStyle}" x:Name="MyDataGrid">
<DataGrid.Columns>
<DataGridTextColumn Header="String" Binding="{Binding}" IsReadOnly="True" />
</DataGrid.Columns>
</DataGrid>
MainWindow.xaml.cs
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.Loaded += new RoutedEventHandler(MainWindow_Loaded);
}
void MainWindow_Loaded(object sender, RoutedEventArgs e)
{
ObservableCollection<string> myCollection = new ObservableCollection<string>();
myCollection.Add("test");
MyDataGrid.ItemsSource = myCollection;
this.DataContext = this;
}
private void DataGridRow_MouseDoubleClick(object sender, MouseButtonEventArgs e)
{
TestWindow window = new TestWindow();
window.Show();
window.Activate();
}
}
TestWindow.xaml
<Window x:Class="WpfApplication2.TestWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="TestWindow" Height="300" Width="300">
<Grid>
<MenuItem Header="Test" Click="Button_Click" />
</Grid>
TestWindow.xaml.cs
public partial class TestWindow : Window
{
public TestWindow()
{
InitializeComponent();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
this.Close();
}
}

You could try modifying your DataGridRow_MouseDoubleClick handler as follows:
private void DataGridRow_MouseDoubleClick( object sender, MouseButtonEventArgs e )
{
this.Dispatcher.BeginInvoke(
( Action )delegate
{
TestWindow window = new TestWindow();
window.Show();
window.Activate();
},
System.Windows.Threading.DispatcherPriority.Background,
null
);
}
That might solve the problem by letting the outstanding events "settle" before creating the new window.