I have a popup with a TextBox that the user should enter a ticket number into, and then when the user presses the enter key I want the ticket number to be passed to the ViewModel which will retrieve the ticket.
Here's the xaml for the TextBox:
<TextBox x:Name="TicketNumber">
<i:Interaction.Triggers>
<i:EventTrigger EventName="KeyDown">
<i:InvokeCommandAction Command="{Binding OpenTicketCommand}"
CommandParameter="{Binding ElementName=TicketNumber,
Path=Text}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</TextBox>
The above works on any keypress, but I really only want it to happen when the enter key is pressed. How would I go about doing that?
EDIT: I am assuming it would have to be done programmatically (hence the title), but if not that's okay too.
You could use InputBindings - KeyBinding as alternative approach.
Something like this:
<TextBox x:Name="TicketNumber">
<TextBox.InputBindings>
<KeyBinding Key="Enter"
Command="{Binding OpenTicketCommand}"
CommandParameter="{Binding ElementName=TicketNumber,
Path=Text}"/>
</TextBox.InputBindings>
</TextBox>
Related
I am struggling with a thing like i have a textbox
<TextBox Name="FilterInputText" Visibility="{Binding VisibiltyAttr}" Width="500" Height="30" Text="{Binding InputText}" HorizontalAlignment="Left" Margin="5">
<TextBox.InputBindings>
<KeyBinding Command="{Binding EnterCommand}" Key="Enter" />
<KeyBinding Command="{Binding DownSelectionCommand}" Key="Down" />
</TextBox.InputBindings>
<i:Interaction.Triggers>
<i:EventTrigger EventName="KeyUp">
<i:InvokeCommandAction Command="{Binding CompleteCommand}" CommandParameter="{Binding Text, ElementName=InputText}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</TextBox>
i have a event triggered here with something input inside textbox with "KeyUp" event. now i am working for autocomplete textbox so i showed suggestions on typing in a list box that is working fine. so i need to bind down key to bind with this text box so that after showing suggestions user can press down key and select his desired option from there.
It will work fine for keybinding for down key.
The problem is with event keyup because any key press inside textbox then this event triggerd. now i am sending textbox value as command parmeter but i also need to send keyeventargs with comamnd pararmter so that i can findout which key is pressed and when downkey comesup i will not further execute the method.
So how i can i pass both textbox value and keyeventargs as command parameter, i am strictly following mvvm pattern.
By default, InvokeCommandAction passes the event args if you do not specify a command parameter. Also, you're textbox is bound to a property on your view model. So, if you change the the code as follows:
<TextBox Name="FilterInputText" Visibility="{Binding VisibiltyAttr}" Width="500" Height="30" Text="{Binding InputText, UpdateSourceTrigger=PropertyChanged}" HorizontalAlignment="Left" Margin="5">
<TextBox.InputBindings>
<KeyBinding Command="{Binding EnterCommand}" Key="Enter" />
<KeyBinding Command="{Binding DownSelectionCommand}" Key="Down" />
</TextBox.InputBindings>
<i:Interaction.Triggers>
<i:EventTrigger EventName="KeyUp">
<i:InvokeCommandAction Command="{Binding CompleteCommand}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</TextBox>
And then make sure your command's execute method has the right event args type for a parameter, then when the CompleteCommand is invoked you should have the event args as the parameter, and you should be able to check the InputText property on your view model for the text value.
Notice that I added "UpdateSourceTrigger=PropertyChanged" to the binding on the TextBox Text property. That will cause the property to be updated in the view model every single time the user types.
See the following link for my source on InvokeCommandAction's default behavior:
https://github.com/Microsoft/XamlBehaviors/issues/126
How to pass pressed key as command parameter in interraction?
<i:Interaction.Triggers>
<i:EventTrigger EventName="PreviewKeyDown">
<i:InvokeCommandAction Command="{Binding SomeCommand}" CommandParameter="???PressedKey???"/>
</i:EventTrigger>
</i:Interaction.Triggers>
EventTrigger doesnt expose details about the event, it just registers to it.
https://msdn.microsoft.com/en-us/library/system.windows.eventtrigger(v=vs.100).aspx
You could instead write a Behavior, there you will control over which key etc:
https://wpftutorial.net/Behaviors.html
this code may solve your issue (It is for search with keypress by Binding) :
<TextBox Height="20" Margin="-30,2,0,0" Name="searchText" Text="{Binding SearchText}" Width="254" >
<i:Interaction.Triggers>
<i:EventTrigger EventName="EditValueChanged">
<i:InvokeCommandAction Command="{Binding SearchFieldCommand}" CommandParameter="{Binding ElementName=searchText, Path=Text,UpdateSourceTrigger=PropertyChanged }" />
</i:EventTrigger>
</i:Interaction.Triggers>
</TextBox>
To better understand this code should be familiar with PropertyChanged
I have a checkbox in a user control. I want the user to be able to check the checkbox when he enters y or 1, and to uncheck it when n or 0 is entered.
Better to have it all in XAML if possible.
Thank you in advance, your help is much appreciated.
You can add a KeyBinding to the UserControl to respond to the key presses in XAML, but you would still need to write a Command that changes the binding property.
<UserControl.InputBindings>
<KeyBinding Key="Y" Command="{Binding MyCommand}" />
<KeyBinding Key="N" Command="{Binding MyCommand}" />
<KeyBinding Key="D0" Command="{Binding MyCommand}" />
<KeyBinding Key="D1" Command="{Binding MyCommand}" />
</UserControl.InputBindings>
Trying to bind the click or checked event on a WPF chekbox to a command in my viewmodel, but im unsure on the technique and the event names, can anyone point me in the right direction?
For now the code compiles but the the trigger does not call the FooCommand
<CheckBox IsChecked="{Binding PartData.ReportIncluded, Mode=TwoWay}"
VerticalAlignment="Center">
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseLeftButtonDown" >
<i:InvokeCommandAction Command="{Binding FooCommand}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</CheckBox>
Looks like you're missing the "On" prefix of your event, i.e. OnMouseLeftButtonDown or OnPreviewMouseLeftButtonDown
Using silverlight, we are looking to move the focus to a textbox.
How do you use mvvm-light to trigger gotfocus?
The view contains:
<TextBox Margin="4,4,0,0" Text="{Binding Path=SearchOID, Mode=TwoWay}">
<i:Interaction.Triggers>
<i:EventTrigger EventName="GotFocus">
<cmd:EventToCommand Command="{Binding GotFocusCommand, Mode=TwoWay}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</TextBox>
How should the ViewModel look?
How do you trigger this from the ViewModel?
Ended up using a TriggerAction, very similar to:
http://www.codeproject.com/Articles/42988/Silverlight-Behaviors-and-Triggers-Making-a-Trigge.aspx