How t add Gesture inside XAML from code behind - wpf

So i have this KeyBinding:
<Window.InputBindings>
<KeyBinding Gesture="Ctrl+Alt+S" Command="{Binding TestCommand}"
HotkeyManager.RegisterGlobalHotkey="True" />
</Window.InputBindings>
And my application have several ToggeButtons that the user need to specify the shortcuts ans i want to be able to change this from code behind:
Gesture="Ctrl+Alt+S"
Any suggestions ?

Create a KeyGesture. The ModifierKeys is a flag enum:
KeyBinding binding = new KeyBinding()
{
Gesture = new KeyGesture(Key.S, ModifierKeys.Control | ModifierKeys.Alt)
};

Related

WPF blocking InputBindings for shortcut when the focus is on TextBox kind of element

I need tabs in TabControl navigated using Ctrl + PageUp/PageDown - previous/next. Everything works fine, until there is a TextBox control inside of a Tab and there is a focus on it. Then the shortcut won't work. Other key combos work fine, but PageUp and PageDown don't.
This is my Tab control:
<TabControl.InputBindings>
<KeyBinding Modifiers="Control"
Key="PageDown"
Command="{Binding Source={StaticResource ShortCutCommands}, Path=TabControlNextItemCommand}"
CommandParameter="{Binding ElementName=TabControl}"/>
<KeyBinding Modifiers="Control"
Key="PageUp"
Command="{Binding Source={StaticResource ShortCutCommands}, Path=TabControlPreviousItemCommand}"
CommandParameter="{Binding ElementName=TabControl}"/>
</TabControl.InputBindings>
Did someone have a similar problem?
I know using commands would be ideal, but if TextBox is eating those key inputs before the KeyBinding has a chance to work, the only solution I know of is to use the PreviewKeyDown event instead of input bindings.
private void TabControl_PreviewKeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.Tab && Keyboard.Modifiers.HasFlag(ModifierKeys.Control))
{
//Invoke command here
}
}

How to use Commands to react to a ListBox

I'm trying to learn Commanding and have set up a simple wpf project to use a custom command. I have a ListBox and a Button on a Window. When the ListBox has the focus and an Item is selected, I want the Button to be enabled, otherwise it should be disabled.
I define a CustomCommand in a separate CustomCommands class:
Public Shared ReceivedFocus As New RoutedCommand
and in my Window I set it up as follows:
<CommandBinding
Command="{x:Static local:CustomCommands.ReceivedFocus}"
CanExecute="CanActivate"
Executed="ChangeSelection">
</CommandBinding>
and use the command for the ListBox as follows:
<ListBox
x:Name="lstInactive">
<i:Interaction.Triggers>
<i:EventTrigger
EventName="GotFocus">
<i:InvokeCommandAction
Command="{x:Static local:CustomCommands.ReceivedFocus}"
</i:InvokeCommandAction>
</i:EventTrigger>
</i:Interaction.Triggers>
</ListBox>
and, finally, the CanActivate routine is:
Private Sub CanActivate(sender As Object, e As CanExecuteRoutedEventArgs)
If lstInactive.SelectedIndex >= 0 Then
e.CanExecute = True
Else
e.CanExecute = False
End If
End Sub
This is not working. The major problem is that I don't understand how to relate the CanExecute value to the Button. Should I ignore the CanExecute value in the CanActivate routine and instead just set the Enabled property of the Button? If so, what is the value of the CanExecute paramter of the CanExecuteRoutedEventArgs?
A second problem is that the GotFocus event is not firing until I select an item in the ListBox a second time.
Or maybe I don't have a grasp on Commanding at all and this is not the right approach. This small project is not important in itself, it is intended to make sure I understand Commanding after reading numerous articles about it before I start to use Commands in "real" projects. Sadly, at this stage it is clear I don't.
This is not working. The major problem is that I don't understand how to relate the CanExecute value to the Button.
Bind its Command property to the same command:
<Button Content="Button" Command="{x:Static local:CustomCommands.ReceivedFocus}" />
The Button should then be enabled or disabled based on the value that you set the CanExecute property to in your CanActivate event handler.
You probably also want to listen to the SelectionChanged event. This works as expected:
<StackPanel>
<StackPanel.CommandBindings>
<CommandBinding
Command="{x:Static local:CustomCommands.ReceivedFocus}"
CanExecute="CanActivate"
Executed="ChangeSelection">
</CommandBinding>
</StackPanel.CommandBindings>
<ListBox x:Name="lstInactive">
<ListBoxItem>first</ListBoxItem>
<ListBoxItem>second</ListBoxItem>
<ListBoxItem>third</ListBoxItem>
<i:Interaction.Triggers>
<i:EventTrigger EventName="SelectionChanged">
<i:InvokeCommandAction Command="{x:Static local:CustomCommands.ReceivedFocus}">
</i:InvokeCommandAction>
</i:EventTrigger>
</i:Interaction.Triggers>
</ListBox>
<Button Content="Button" Command="{x:Static local:CustomCommands.ReceivedFocus}" />
</StackPanel>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void CanActivate(object sender, CanExecuteRoutedEventArgs e)
{
e.CanExecute = lstInactive.SelectedIndex >= 0;
}
private void ChangeSelection(object sender, ExecutedRoutedEventArgs e)
{
}
}

Assign shortcut key in WPF Ribbon Button

I have a WPF Ribbon Button and I want it to have a shortcut key. (e.g. Ctrl+A). Been searching in google but lost to get a possible answer. Does anyone knows how I might deal with this? Thanks =)
Here is what I have so far
<my:RibbonButton Name="rb1" Content="Images/save.png" />
<my:RibbonButton Name="rb2" Content="Images/abort.png" />
you may perhaps use UIElement.InputBindings with KeyBinding
example
<Window.InputBindings>
<KeyBinding Key="S"
Modifiers="Control"
Command="{Binding Save}" />
<KeyBinding Key="A"
Modifiers="Control"
Command="{Binding Abort}" />
</Window.InputBindings>
using this approach you can bind the input gestures to the commands which buttons are using
assumed code
<my:RibbonButton Name="rb1" Content="Images/save.png" Command="{Binding Save}" />
<my:RibbonButton Name="rb2" Content="Images/abort.png" Command="{Binding Abort}" />
from MSDN: KeyBinding
A KeyBinding associates a KeyGesture with a ICommand, such as a RoutedCommand. RoutedCommand is the primary implementation of the ICommand interface for the WPF commanding system . In general, when the KeyGesture is executed the command is invoked, although the command behavior is further influenced by command-specific factors such as the CanExecute value.
I prefer doing it in code behind. I am using the code in my program.
Hope it help.
private void AddHotKeys()
{
try
{
RoutedCommand firstHotkey = new RoutedCommand();
firstHotkey .InputGestures.Add(new KeyGesture(Key.S, ModifierKeys.Alt));
CommandBindings.Add(new CommandBinding(firstHotkey , Save));
}
catch (Exception err)
{
//handle exception error
}
}

How to trigger ViewModel command for a specific button events

How can a command on a ViewModel be invoked by a specific event of a button, such as MouseDoubleClick?
You can use the EventTrigger in the System.Windows.Interactivity namespace, which is part of the so-called Prism framework. If you're just getting started with MVVM, don't care too much for Prism by now, but keep it in mind for later. Anyway, you can steel the EventTrigger
It works like this:
Reference the assembly System.Windows.Interactivity.dll
In XAML, reference the namespace:
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
Then in your Button or any other control, add a EventTrigger like this:
<Button Content="Button">
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseDoubleClick">
<i:InvokeCommandAction Command="{Binding CommandToBindTo}"
CommandParameter="{Binding CommandParameterToBindTo}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</Button>
This way, you bind your event to a Command on your DataContext.
Remark
To clarify the usage, here's a kind of real life example including the ViewModel. The fictional requirement is to allow the user to select an item in a list and then perform a command which takes the selected item as a parameter:
<ListBox x:Name="ItemsList" ItemsSource="{Binding Items}" />
<Button Content="Do something with selected item">
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseDoubleClick">
<i:InvokeCommandAction Command="{Binding DoSomethingCommand}"
CommandParameter="{Binding SelectedItem,
ElementName=ItemsList}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</Button>
And that would be the ViewModel. Note how the parameter to the command is used, in the example with a generic version of a DelegateCommand object as you get it in every MVVM framework (sometimes RelayCommand). This class takes the type of the required parameter as a generic parameter (here ItemViewModel) and requires a method which takes an according parameter (here ExecuteDoSomethingWithItem(ItemViewModel ...)). The rest is WPF magic: The oject to which the CommandParameter property is bound in your XAML will be passed through as the parameter in your Execute(...) function.
public class ViewModel
{
ObservableCollection<ItemViewModel> Items { get; set; }
public ICommand DoSomethingCommand
{
get
{
return _doSomethingCommand ??
(_doSomethingCommand = new DelegateCommand<ItemViewModel>(ExecuteDoSomethingWithItem));
}
}
private DelegateCommand<ItemViewModel> _doSomethingCommand;
private void ExecuteDoSomethingWithItem(ItemViewModel itemToDoSomethingWith)
{
// Do something
}
public ViewModel()
{
Items = new ObservableCollection<ItemViewModel>();
// Fill the collection
}
}
Have fun with learning MVVM, it's worth it.
you can use attached command behaviors
=> http://geekswithblogs.net/HouseOfBilz/archive/2009/08/21/adventures-in-mvvm-ndash-generalized-command-behavior-attachments.aspx
You need to do a lot of pluming yourself if you going to use Command and Event Binding from out of the box WPF. You can gain a lot of just using existing framework such as MVVM Light Toolkit, or Cliburn Micro that already provide command and even binding.

Defining MenuItem Shortcuts

I need a simple way to set a shortcut for menu items.
But this donĀ“t work with shortcut, just with click:
<MenuItem Header="Editar">
<MenuItem Header="Procurar" Name="MenuProcurar"
InputGestureText="Ctrl+F"
Click="MenuProcurar_Click">
<MenuItem.ToolTip>
<ToolTip>
Procurar
</ToolTip>
</MenuItem.ToolTip>
</MenuItem>
</MenuItem>
I am using WPF 4.0
H.B. was right... I just wanted to add more precisions.
Remove the Click event on your MenuItem and associate it with a Command instead.
1 - Add/create your commands:
<Window.CommandBindings>
<CommandBinding Command="Open" Executed="OpenCommandBinding_Executed"/>
<CommandBinding Command="SaveAs" Executed="SaveAsCommandBinding_Executed"/>
</Window.CommandBindings>
The commands are refering to the following code:
private void OpenCommandBinding_Executed(object sender, ExecutedRoutedEventArgs e)
{
Open();//Implementation of open file
}
private void SaveAsCommandBinding_Executed(object sender, ExecutedRoutedEventArgs e)
{
SaveAs();//Implementation of saveAs
}
2 - Associate the commands with the wanted keys:
<Window.InputBindings>
<KeyBinding Key="O" Modifiers="Control" Command="Open"/>
<KeyBinding Key="S" Modifiers="Control" Command="SaveAs"/>
</Window.InputBindings>
3 - Finally assign the commands with you menu item (InputGestureText is just a decorating text):
<Menu Name="menu1">
<MenuItem Header="_File">
<MenuItem Name="menuOpen" Header="_Open..." Command="Open" InputGestureText="Ctrl+O"/>
<MenuItem Name="menuSaveAs" Header="_Save as..." Command="SaveAs" InputGestureText="Ctrl+S"/>
</MenuItem>
</Menu>
That way multiple inputs may be associated to the same command.
You need to use KeyBindings (and CommandBindings if you (re)use RoutedCommands such as those found in the ApplicationCommands class) for that in the controls where the shortcuts should work.
e.g.
<Window.CommandBindings>
<CommandBinding Command="New" Executed="CommandBinding_Executed" />
</Window.CommandBindings>
<Window.InputBindings>
<KeyBinding Key="N" Modifiers="Control" Command="New"/>
</Window.InputBindings>
For custom RoutedCommands:
static class CustomCommands
{
public static RoutedCommand DoStuff = new RoutedCommand();
}
usage:
<Window
...
xmlns:local="clr-namespace:MyNamespace">
<Window.CommandBindings>
<CommandBinding Command="local:CustomCommands.DoStuff" Executed="DoStuff_Executed" />
</Window.CommandBindings>
<Window.InputBindings>
<KeyBinding Key="D" Modifiers="Control" Command="local:CustomCommands.DoStuff"/>
</Window.InputBindings>
...
</Window>
(It is often more convenient to implement the ICommand interface rather than using RoutedCommands. You can have a constructor which takes delegates for Execute and CanExecute to easily create commands which do different things, such implementations are often called DelegateCommand or RelayCommand. This way you do not need CommandBindings.)
In my humble opinion is much easier just to use _ at the Header. This will create automatically the desired HotKey.
For example:
<MenuItem Header="_Editar">
<MenuItem Header="_Procurar" Name="MenuProcurar"
InputGestureText="Ctrl+F"
Click="MenuProcurar_Click">
<MenuItem.ToolTip>
<ToolTip>
Procurar
</ToolTip>
</MenuItem.ToolTip>
</MenuItem>
</MenuItem>
I'm overly biased by Windows.Forms & gulp VB 6, so I kind of agree with Jonathan and Jase that there's got to be a more straightforward/procedural method to statically wire up event handlers that aren't necessarily CommandBindings. And there is, I think.
A good tutorial for using non-CommandBinding handlers like this, but with an emphasis on buttons, can be found in this MSDN blog post, I believe. I'll distill and target MenuItems...
Creating the ICommand
First, create a class implementing ICommand. You can put this anywhere, of course, even in your MainWindow.xaml.cs file if you wanted, to keep your demo code insanely simple. You'll probably want to make CanExecute more complicated when you want to dis/en/able menu items later, but for now, we'll just always have our menu items enabled.
public class HelloWorldCommand : ICommand
{
public void Execute(object parameter)
{
MessageBox.Show(#"""Hello, world!"" from "
+ (parameter ?? "somewhere secret").ToString());
}
public bool CanExecute(object parameter)
{
return true;
}
public event EventHandler CanExecuteChanged;
}
As the tutorial helpfully points out, you could call this command from anywhere already, with code like...
var hwc = new HelloWorldCommand();
if (hwc.CanExecute(this))
hwc.Execute(this);
Declaring your command in the Window
So let's add a sort of "declaration" for the HelloWorldCommand to our Window so that we can use it later. Inside of your Window tags, register the command as a resource:
<Window.Resources>
<local:HelloWorldCommand x:Key="hwc"/>
</Window.Resources>
Now we have a neat shortcut for linking to this "locally namespaced" command, "hwc", though you can obviously use any string you want. We'll use that a lot in our xaml.
Wiring up (and reusing!) the command
Let's add our MenuItems to our xaml. I've replaced the stock Grid with a DockPanel because that's the easiest way (for me) to have equi-spaced widgets that fill the Window, though I've left all of the rest of my UI out.
Note the Command="{StaticResource hwc}"s sprinkled into each MenuItem declaration. The key is the hwc in there - remember that that's our shortcut for the HelloWorldCommand that we set up at the Window level. And, of course, StaticResource says just to look it up the Window's resources. We're not binding anything; we're just using our shortcut.
<DockPanel LastChildFill="True">
<Menu DockPanel.Dock="Top">
<MenuItem Header="_File">
<MenuItem
Header="_Open"
Command="{StaticResource hwc}"
>
<MenuItem.CommandParameter>
<!-- so you could make this object as complex as you wanted,
like, say, your entire Window. See magic incantation, below. -->
<Binding RelativeSource="{RelativeSource FindAncestor, AncestorType=Window}" />
</MenuItem.CommandParameter>
</MenuItem>
<MenuItem
Header="_Close"
Command="{StaticResource hwc}"
CommandParameter="Close"
InputGestureText="Ctrl+G" />
<MenuItem
Header="_Save"
Command="{StaticResource hwc}"
CommandParameter="Save" />
<Separator />
<MenuItem
Header="_Quit"
Command="{StaticResource hwc}"
CommandParameter="Quit" />
</MenuItem>
</DockPanel>
CommandParameters to distinguish event sources
Note that we're using the same Command for everything! But how can we tell which widget threw the event? For that, you need to use the CommandParameter -- remember our Execute method's signature: Execute(object parameter). That CommandParameter parameter is what we can use to know how to handle the event. Try running this and note that the MessageBox will use whatever's in CommandParameter to let you know the source of the event. We're doing it all manually, but that's not too bad.
Also note that you can make these objects as complicated as you'd like. You can use a property in the MenuItem tag to define the parameter, or can use "real" <MenuItem.CommandParameter> tags, like in the Open menu item, above, to define something complex. In this case, we're passing the entire parent Window object, which was the easiest (though not the cleanest) way to throw our VB6-ish context into the event handler code.
Adding keyboard shortcuts to MenuItems (aka, "Answering the OP")
And now we can finally answer the original question! Let's finally wire up a keyboard shortcut for the Close menu item. You'll note that we've already declared an InputGestureText. By itself, InputGestureText is only cosmetic. If we were overly picky, we could argue the mechanism for creating the keyboard shortcut doesn't have any direct, inherent relationship with the MenuItem at all!
We need to instead (or additionally) register a listener for Ctrl-G at the Window level to catch the keystroke. So at the top level of your Window tags, insert this (taken essentially from here):
<Window.InputBindings>
<KeyBinding Modifiers="Control"
Key="G"
Command="{StaticResource hwc}"
CommandParameter="window input binding"
/>
</Window.InputBindings>
Note that you could put CommandParameter tags in your KeyBinding by moving it from a self-closing piece of XML to "real" open and close KeyBinding tags.
And we're done. Run your app, and press Ctrl-G. Whaddup.
Pretty straightforward, once you've got the players straight, and much less magic binding-y than most intros to commands and MenuItems, I think.
Possible pro tip:
The whole CommandBinding thing confused me for a while. This is just for specific command types, I believe. That is, you can't just wire up any Command you like. Stuff like what's bragged about here (in what's admittedly a decent intro tutorial!)...
It might not be completely obvious, but by using commands, we just got a whole bunch of things for free: Keyboard shortcuts, text and InputGestureText on the items and WPF automatically enables/disables the items depending on the active control and its state. In this case, Cut and Copy are disabled because no text is selected, but Paste is enabled, because my clipboard is not empty!
... is kind of magic-y and not necessarily good, and can be confusing when you're new to WPF menus.
You can also declare RoutedUICommand in XAML:
<Window.Resources>
<RoutedUICommand x:Key="BuildCmd" Text="Build">
<RoutedUICommand.InputGestures>
<KeyGesture>CTRL+SHIFT+B</KeyGesture>
</RoutedUICommand.InputGestures>
</RoutedUICommand>
</Window.Resources>
Do the binding
<Window.CommandBindings>
<CommandBinding Command="{StaticResource BuildCmd}" Executed="BuildCmdExecuted"/>
</Window.CommandBindings>
And in MenuItem
<MenuItem Command="{StaticResource BuildCmd}"/>
Another solution is discussed here.
Here is solution in PowerShell:
Define your XAML file:
<Window x:Class="WpfApp1.Window1"
xmlns:local="clr-namespace:WpfApp1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="My App" Height="620" Width="950" >
<Window.InputBindings>
<KeyBinding Key="S" Modifiers="Ctrl"/>
</Window.InputBindings>
<Grid x:Name="MainGrid">
<!--Your GUI is here-->
<Menu Margin="0">
<MenuItem Header="_File">
<MenuItem x:Name="SaveProfile" Header="_Save Profile" InputGestureText="Ctrl+S"/>
</MenuItem>
</Menu>
</Grid>
</Window>
Add new type to be able to create Command(s)
Add-Type #"
public class DelegateCommand : System.Windows.Input.ICommand
{
private System.Action<object> _action;
public DelegateCommand(System.Action<object> action)
{
_action = action;
}
public bool CanExecute(object parameter)
{
return true;
}
public event System.EventHandler CanExecuteChanged = delegate { };
public void Execute(object parameter)
{
_action(parameter);
}
}
"#
Create and assign new Command to the previously defined KeyBinding, it is first key binding, that is why I'm addressing it with [0].
Note:in my case I saved the handle to the main Window in $hash.Window variable, you should put here the link to your main window object, that you created with [Windows.Markup.XamlReader]::Load($xamlXmlNodeReader) command or other window creation command.
$hash.Window.InputBindings[0].Command = New-Object DelegateCommand( { Save-Profile } )
Create your function that you put into command
function Save-Profile {
Write-Host "Save Profile"
# Your logic goes here
}
Thanks to Nicholas Wolverson for the tips on how to create the Type for Command.
This work for me
<ContextMenu PreviewKeyUp="ContextMenu_PreviewKeyUp">
<MenuItem Header="Delete" Click="DeleteID" />
</ContextMenu>
Code behind:
private void ContextMenu_PreviewKeyUp(object sender, KeyEventArgs e)
{
ContextMenu contextMenu = sender as ContextMenu;
if (e.Key == Key.D)
{
//DELETE ID
}
contextMenu.IsOpen = false;
}

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