We are using EditControl(component from the toolbox) from Syncfusion framework Essential Studio to write a small code-editor.
We want to popup the auto-complete window after pressing the shortcut CTRL + SPACE without typing the space-char into the EditorWindow.
Is there any way to disable typing characters into the EditControl?
Private Sub editControl1_KeyDown(sender As Object, e As KeyEventArgs)
If e.Control Then
' Do something here
If e.KeyCode = Keys.Space Then
EditControl1.ShowContextChoice()
Dim context = EditControl1.ContextChoiceController
For Each item As IConfigLexem In lexeme
context.Items.Add((item).BeginBlock, CStr(m_MethodComments(item.ID)), Me.EditControl1.ContextChoiceController.Images("Image" & item.FormatName))
Next
End If
End If
End Sub
You can set-up key bindings within the control which will prevent you needing to trap the KeyDown event.
For example, create some Sub where you configuring the properties of the control (called Editor in my example) and add these lines:
AddHandler Editor.Commands.Add("Editor.ContextChoice").ProcessCommand, AddressOf Editor.ShowContextChoice
Editor.KeyBinder.BindToCommand(Keys.Control Or Keys.Space, "Editor.ContextChoice")
Check your install for a working example of this functionality. It is a good idea to elect to install the samples as they are very comprehensive.
Related
I am adding controls at run time in a WPF App, these are all different types of control so are passed as a UIElement. I then get the type of control and can set the properties using SetValue. As I have a lot of control types to implement what I am now trying to do is is add an event to each control but can only seem to do this using Addhandler which requires a lot of extra code for each control as shown below. I am looking for a solution to allow me to add the error handler to the UIElement without prior conversion using a Cast, I am not sure this is possible?
Select Case Control.GetType()
Case GetType(ExtendedTextBox)
Dim newControl As ExtendedTextBox = TryCast(Control, ExtendedTextBox)
'Dim newCtl As UIElement = TryCast(Control, ExtendedTextBox)
If newControl IsNot Nothing Then
newControl.SetValue(ExtendedTextBox.HorizontalAlignmentProperty, HorizontalAlignment.Left)
newControl.SetValue(ExtendedControlProperties.HighlightTextOnFocusProperty, True)
newControl.SetValue(ExtendedControlProperties.MandatoryProperty, True)
AddHandler newControl.HasErrors, AddressOf UpdateErrorStatus
End If
I was incorrectly prefixing my validation with "Customer." which as in inherited control was causing the issue, once removed it works as expected.
I do not know how to specify in the title, this is in WPF visual basic. I want to know how do I write a code so that when a button is clicked, the tabcontrol selection will be = 1
Here is what I have in my MainWindow, RightWindowCommands:
<Button Content="Information" Cursor="Hand" Click="InformationButton_OnClick"
ToolTip="View the information"
x:Name="InformationView"/>
However, I did not use the WPF tools' Button, as this is a GUI that I have to place the button at RightWindowCommands, I want to know how to come out with the code so that InformationButton_OnClick gives me tabControl.SelectedIndex = 1. Please guide me on writing this code out
Here is a nice example for onclick event handling a picture, you can change it to a number instead of picture.
`AddHandler pic.Click, AddressOf pic_Click'
Private Sub pic_Click(ByVal sender As Object, ByVal e As EventArgs)
Dim pic As PictureBox = DirectCast(sender, PictureBox)
' etc...
End Sub
Source : add on click event to picturebox vb.net
In my project I've got a MainWindow that opens up a second Window. Inside the second Window there is a Frame and I start a navigationservice inside the Frame. Also in the second Window I've got a KeyDown method that calls Me.Close when the user presses the Escape key. Anyway, when the second Window closes a System.Windows.Threading.DispatcherTimer() inside one of the pages in the navigation service doesn't end. Any ideas on how can I close the second Window and terminate the DispatcherTimer inside the navigationservice?
Thanks
Mike
p.s. I can supply source code if anyone wants to look at what I've got...
(Hey EkoostikMartin - this is a follow up to your comments..)
So I've made some progress on this. I've add:
AddHandler Me.KeyDown, AddressOf Page_KeyDown
AddHandler Me.PreviewKeyDown, AddressOf Page_PreviewKeyDown
to the Page that has the timer. And inside the page I've defined both methods like:
Private Sub Page_KeyDown(sender As Object, e As KeyEventArgs)
If e.Key = Key.Escape Then
dTimer.Stop()
MessageBox.Show("Exit Page")
End If
End Sub
Private Sub Page_PreviewKeyDown(sender As Object, e As KeyEventArgs)
If e.Key = Key.Escape Then
dTimer.Stop()
MessageBox.Show("Exit Page")
End If
End Sub
And the second Window has this:
Private Sub Window_KeyDown(sender As System.Object, e As System.Windows.Input.KeyEventArgs)
'Escape Key Exits Program
If e.Key = Key.Escape Then
Me.Close()
End If
End Sub
So when I'm in the navigation service and navigated to the page with the Timer and I press "Esc" I get the message "Exit Page" and then the Window closes. This is good!
(I don't think I need both the KeyDown and PreviewKeyDown. When I press "Esc" I'm actually getting two "Exit Page" pop-ups)
There is a problem though: It seems like the Page doesn't get the KeyDown events unless I move the focus to a textbox or combobox and if I don't do this pressing the "Esc" key calls the second Window's Window_KeyDown and not the Page's KeyDown event which means the timer on the page doesn't get stopped even after the second Window is closed. Does anyone know a way to get the page focus when the page loads so that I can get the KeyDown event without manually changing the focus to a control on the Page?
Thanks!
Ok - I finally resolved this situation by way of a work around. In my second Window I've created a list of type DispatcherTimer:
Public clndTimer As New List(Of System.Windows.Threading.DispatcherTimer)
I can access this list from a Page that is inside my Navigation service. Here's the code in the Page:
Dim dTimer As New DispatcherTimer()
dTimer.Start()
Dim wSecondWindow As New SecondWindow
wSecondWindow = Window.GetWindow(Me)
If wSecondWindow IsNot Nothing Then
wSecondWindow.clndTimer.Add(dTimer)
End If
And then I capture the key event in the second Window. This is the method in the second Window:
Private Sub Window_KeyDown(sender As System.Object, e As System.Windows.Input.KeyEventArgs)
'Escape Key Exits Program
If e.Key = Key.Escape Then
For Each dt In clndTimer
dt.Stop()
Next
Me.Close()
End If
End Sub
Doing it this way I don't need either the Page_KeyDown or PreviewKeyDown methods in my Page which is good because they were behaving unreliably. (see answer above)
So what do you think? I'm not totally sure about the way I get the Second window or how I check it for null in the Page but otherwise this seems to make sense.
Thanks!
This code should fire when is pressed, but not +. What change do I need to make it work correctly?
Private Sub cmdDeleteRow_KeyDown(ByVal sender As System.Object, ByVal e As System.Windows.Input.KeyEventArgs)
If e.Key = Input.Key.Tab Then
'DO stuff
End If
End Sub
Hmh, yor question title doesn't match the content (no reference to the shift key)!
Are you trying to avoid "Do stuff" when Shift+Tab is pressed? If so you need to check the modifier keys, whether Shift is pressed or not. I don't know the exact code for vb.net (you can easily google for it), but in c# there's a Keyboard.Modifiers property that can be accessed...
I'm pondering taking the plunge to WPF from WinForms for some of my apps, currently I'm working on the combined barcode-reader/text-entry program (healthcare patient forms).
To be able to process the barcode characters, I rely on the Keypreview property in WinForms (because barcodes can be scanned regardless of what control has the focus).
But I cannot seem to find a KeyPreview property in neither VS2008 or VS2010, for a WPF app.
Is there an alternative approach/solution to handle my barcode characters in WPF?
Rgrds Henry
use the override in your own UserControls or Controls (this is an override from UIElement)
protected override void OnPreviewKeyDown(System.Windows.Input.KeyEventArgs e) {
base.OnPreviewKeyDown(e);
}
if you want to preview the key down on any element which you dont create you can do this:
Label label = new Label();
label.PreviewKeyDown += new KeyEventHandler(label_PreviewKeyDown);
and then have a handler like so :-
void label_PreviewKeyDown(object sender, KeyEventArgs e) {
}
if you mark the event as handled (e.Handled = true;) this will stop the KeyDown event being raised.
Thanks got it working! Only problem was I'm coding in VB not C#, but the basic idea holds. Neat to create a label out of thin air and use it to insert yourself in the event stream.
If someone else is interested of the same solution but in VB for WPF, here's my test program, it manages to toss all 'a' characters typed, no matter what control has the focus:
Class MainWindow
Dim WithEvents labelFromThinAir As Label
Private Sub Window_Loaded(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles MyBase.Loaded
AddHandler MainWindow.PreviewKeyDown, AddressOf labelFromThinAir_PreviewKeyDown
End Sub
Private Sub labelFromThinAir_PreviewKeyDown(ByVal sender As Object, ByVal e As KeyEventArgs)
TextBox1.Text = e.Key ' watch 'em coming
If (44 = e.Key) Then e.Handled = True
End Sub
End Class
P.S. This was my first post on stackoverflow, really a useful site. Perhaps I'll be able to answer some questions in here myself later on :-)
WPF uses event bubbling and tunneling. In other words the events travel down and up the visual element tree. Some events will have a corresponding Preview event. So MouseDown will have a PreviewMouseDown that you can respond to. Check out this link and scroll down to the WPF Input Events section.