This may have a very simple solution but I am pretty new to this. I am trying add child items into a selected treeView item with the click of a button. Code works fine with nothing selected but seems Treeview1.selectedItem doesn't have an .Add method.
Imports System.Windows.Controls.TreeView
Class MainWindow
Private Sub addNodeButton_Click(sender As Object, e As RoutedEventArgs) Handles addNodeButton.Click
Dim n As String = "Model"
If TreeView1.SelectedItem Is Nothing Then
TreeView1.Items.Add(n)
Else
TreeView1.SelectedItem.add("test")
End If
End Sub
End Class
Any help appreciated.
Ok. I knew it would turn out to be simple. I was initially adding items as Strings insead of TreeViewItems and thus couldn't add children. Fixed code below:
Private Sub addNodeButton_Click(sender As Object, e As RoutedEventArgs) Handles addNodeButton.Click
Dim n As New TreeViewItem
n.Header = "Model"
If TreeView1.SelectedItem Is Nothing Then
TreeView1.Items.Add(n)
Else
Dim tempitem As New TreeViewItem
tempitem = TreeView1.SelectedItem
Dim newitem As New TreeViewItem
newitem.Header = "test"
tempitem.Items.Add(newitem)
End If
End Sub
Related
I have a XamDataGrid in my MainWindow which has a Public Shared List(Of Artikelstammdaten) as DataSource. After opening a few other forms I want to add more data to the XamDataGrid with a button click. I thought the easiest way would be just to update the DataSource, but I get an Error:
The reference to an unreleased member requires an object reference.
This is what I have tried:
Private Sub Add_Click(sender As Object, e As RoutedEventArgs)
Dim update = MainWindow.listArtikelstammdaten.Concat(CType(Import.ComparedAccessData, IEnumerable(Of Artikelstammdaten)))
dgArticleMasterData.DataSource = update
Me.Close()
End Sub
If dgArticleMasterData is defined in the MainWindow class, you need to get a reference to the MainWindow instance to be able to access it.
You should be able to find it in the Application.Current.Windows collection:
Private Sub Add_Click(sender As Object, e As RoutedEventArgs)
Dim update = MainWindow.listArtikelstammdaten.Concat(CType(Import.ComparedAccessData, IEnumerable(Of Artikelstammdaten)))
Dim window = Application.Current.Windows.OfType(Of MainWindow).FirstOrDefault()
If window IsNot Nothing Then
window.dgArticleMasterData.DataSource = update
End If
Me.Close()
End Sub
Form3 contains array elements which loads its item from form1 listbox.
When form3 is closed and again reopened then the array is becoming empty and there are no values in array that I can compare to.
Have tried to get another listbox in form3 and get elements through it by refreshing it everytime in every run. but it is not working.
form1
Do while xr.read()
If xr.NodeType = XmlNodeType.Element AndAlso xr.Name = "Rating" Then
dim rating(0) as string = {xr.ReadElementString}
ListBox5.Items.Add(rating(0))
end If
Private Sub RatingsToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles RatingsEnteredVsAppxRatingsToolStripMenuItem.Click
Dim myform As Form3
myform = New Form3
myform.Show(Form3)
InitializeComponent()
End Sub
form3
Public class form3
Dim toarray() As String = Form1.ListBox5.Items.OfType(Of String).ToArray()
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
'Compare operations to array
end sub
end class
I expect that when form3 is closed and opened from the menustrip of form1 again then the toarray should still contain the elements of listbox5.
Remove InitializeComponent() after showing Form3. It is recreating your control & removing the items that you have added to it when reading your xml.
Private Sub RatingsToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles RatingsEnteredVsAppxRatingsToolStripMenuItem.Click
Dim myform As Form3
myform = New Form3
myform.Show(Form3)
End Sub
Instead accessing the control "Form1.ListBox5" directly, you could provide an object/class that contains the values (rating array) and pass it to the Form1.ListBox5 and Form3 after instantiating.
I created a usercontrol with a treeview inside it. The treeview will be populated if I add nodes in the onload handler of the usercontrol. But after that(for example, I click a button in its parent form), the treeview will not refresh. I can see the nodes was updated in memory, but it just cannot display on the screen. I called refresh/update after adding nodes. Any suggestion is appreciated.
I put a quick test together based on your description and it seems to paint just fine.
UserControl1
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
Partial Class UserControl1
Inherits System.Windows.Forms.UserControl
'UserControl overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
Try
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
Finally
MyBase.Dispose(disposing)
End Try
End Sub
'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer
'NOTE: The following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.TreeView1 = New System.Windows.Forms.TreeView
Me.SuspendLayout()
'
'TreeView1
'
Me.TreeView1.Dock = System.Windows.Forms.DockStyle.Fill
Me.TreeView1.Location = New System.Drawing.Point(0, 0)
Me.TreeView1.Name = "TreeView1"
Me.TreeView1.Size = New System.Drawing.Size(150, 150)
Me.TreeView1.TabIndex = 0
'
'UserControl1
'
Me.AutoScaleDimensions = New System.Drawing.SizeF(6.0!, 13.0!)
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
Me.Controls.Add(Me.TreeView1)
Me.Name = "UserControl1"
Me.ResumeLayout(False)
End Sub
Friend WithEvents TreeView1 As System.Windows.Forms.TreeView
End Class
Public Class UserControl1
Public Sub AddNewNode(ByVal text As System.String)
TreeView1.Nodes.Add(text)
End Sub
End Class
Put the usercontrol on a form with a button
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
UserControl11.AddNewNode(Now.ToString)
End Sub
End Class
If you are seeing proper painting as well then look at any graphics handling in the parent form then the usercontrol then the controls within the usercontrol. We really need more info.
Thank you, Dave. I figured it out. I put the usercontrol twice to my form by mistake(I cannot remember how I did it). And the one I operate is underneath the other one. That's why I cannot see it. Sorry for wasting your time.
I have a problem with my TreeView in a WPF application (Framework 3.5 SP1).
It's a TreeVIew with 2 Levels of Data. I expand / collapse the items of the first level in a particular way (with a single mouse-click on the TreeViewItem). Again when I expand a first-level TreeViewItem, I add some second-level TreeViewItems to the group (it's an important detail, infact if I don't add the items the problem doesn't occur). All works good until the TreeView loses focus.
If, for example, I expand the TreeViewItem at the first position, adding at the same time one element to the second-level, then I click on a button (to let the TreeView lose the focus), and then I click again on the TreeViewItem at the third position to expand it, the TreeViewItem that results from the hit-test with the mouse position is not the "real" TreeViewItem (in this case the third), but a TreeViewItem which is in an higher position than the one clicked (in this case the second).
I have tried to use the UpdateLayout method on the TreeView-LostFocus event, but without results. Probably I need a method that does the opposite: starting from the UI, refresh the object that contains the position of the TreeViewItems.
Can you, please, help me?
Thank you!
Pileggi
This is the code:
' in this way I tried to put remedy at the problem, but it doesn't work.
Private Sub tvArt_LostFocus(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles tvArt.LostFocus
Me.tvArt.UpdateLayout()
e.Handled = True
End Sub
' here I expand / collapse the items of the first level of my TreeView
Private Sub tvArt_PreviewMouseUp(ByVal sender As System.Object, ByVal e As MouseButtonEventArgs) Handles tvArt.PreviewMouseUp
Dim p As Point = Nothing
Dim tvi As TreeViewItem = getItemFromMousePosition(Of TreeViewItem)(p, e.OriginalSource, Me.tvArt)
If tvi Is Nothing = False Then
If tvi.HasItems Then
Dim be As BindingExpression = BindingOperations.GetBindingExpression(tvi, TreeViewItem.ItemsSourceProperty)
Dim ri As P_RicambiItem = DirectCast(be.DataItem, P_RicambiItem)
If ri.isExpanded = False then
' here I add items to the second level collection
End If
ri.isExpanded = Not ri.isExpanded
End If
End If
e.Handled = True
End Sub
Private Function getItemFromMousePosition(Of childItem As DependencyObject)(ByRef p As Point, ByVal sender As UIElement, _
ByVal _item As UIElement) As childItem
p = sender.TranslatePoint(New Point(0, 0), _item)
Dim obj As DependencyObject = DirectCast(_item.InputHitTest(p), DependencyObject)
While obj Is Nothing = False AndAlso TypeOf obj Is childItem = False
obj = VisualTreeHelper.GetParent(obj)
End While
Return DirectCast(obj, childItem)
End Function
I have find this solution (but I don't like it very much). The problem is depending from the added items that wpf, for some reasons, doesn't remember that exist. Then I do a "manual" refresh with a method that clear and re-add all the items in the source-collection:
Public Sub RefreshData(ByVal RicambiListPass As ObservableCollection(Of P_RicambiItem))
Dim l As New List(Of P_RicambiItem)
l.AddRange(RicambiListPass)
_RicambiList.Clear()
For Each i As P_RicambiItem In l
_RicambiList.Add(i)
Next
End Sub
Because of the changes I have done to my post I have thinked to open another thread. In the new thread I have posted my (provvisory) solution.
You can find it here
Hi!
I have a problem with my TreeView in a WPF application (Framework 3.5 SP1).
It's a TreeVIew with 2 Levels of Data. I expand / collapse the items of the first level in a particular way (with a single mouse-click on the TreeViewItem). Again when I expand a first-level TreeViewItem, I add some second-level TreeViewItems to the group (it's an important detail, infact if I don't add the items the problem doesn't occur). All works good until the TreeView loses focus.
If, for example, I expand the TreeViewItem at the first position, adding at the same time one element to the second-level, then I click on a button (to let the TreeView lose the focus), and then I click again on the TreeViewItem at the third position to expand it, the TreeViewItem that results from the hit-test with the mouse position is not the "real" TreeViewItem (in this case the third), but a TreeViewItem which is in an higher position than the one clicked (in this case the second).
I have tried to use the UpdateLayout method on the TreeView-LostFocus event, but without results. Probably I need a method that does the opposite: starting from the UI, refresh the object that contains the position of the TreeViewItems.
Can you, please, help me?
Thank you!
Pileggi
This is the code:
' in this way I tried to put remedy at the problem, but it doesn't work.
Private Sub tvArt_LostFocus(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles tvArt.LostFocus
Me.tvArt.UpdateLayout()
e.Handled = True
End Sub
' here I expand / collapse the items of the first level of my TreeView
Private Sub tvArt_PreviewMouseUp(ByVal sender As System.Object, ByVal e As MouseButtonEventArgs) Handles tvArt.PreviewMouseUp
Dim p As Point = Nothing
Dim tvi As TreeViewItem = getItemFromMousePosition(Of TreeViewItem)(p, e.OriginalSource, Me.tvArt)
If tvi Is Nothing = False Then
If tvi.HasItems Then
Dim be As BindingExpression = BindingOperations.GetBindingExpression(tvi, TreeViewItem.ItemsSourceProperty)
Dim ri As P_RicambiItem = DirectCast(be.DataItem, P_RicambiItem)
If ri.isExpanded = False then
' here I add items to the second level collection
End If
ri.isExpanded = Not ri.isExpanded
End If
End If
e.Handled = True
End Sub
Private Function getItemFromMousePosition(Of childItem As DependencyObject)(ByRef p As Point, ByVal sender As UIElement, _
ByVal _item As UIElement) As childItem
p = sender.TranslatePoint(New Point(0, 0), _item)
Dim obj As DependencyObject = DirectCast(_item.InputHitTest(p), DependencyObject)
While obj Is Nothing = False AndAlso TypeOf obj Is childItem = False
obj = VisualTreeHelper.GetParent(obj)
End While
Return DirectCast(obj, childItem)
End Function
Your hit test code seems a little odd. You ignore the mouse position given by the MouseButtonEventArgs object, and then do a hit test in the TreeView against the upper-left corner of the control that was clicked. This will normally give you back the same control again, and I suspect your weird behavior is in the cases where it doesn't. Instead of doing TranslatePoint and InputHitTest, just use the sender directly. Your helper function reduces to:
Private Function getParentOfType(Of childItem As DependencyObject)(ByVal sender As UIElement) As childItem
Dim obj As DependencyObject = sender
While obj Is Nothing = False AndAlso TypeOf obj Is childItem = False
obj = VisualTreeHelper.GetParent(obj)
End While
Return DirectCast(obj, childItem)
End Function
You can actually make it simpler again by taking advantage of the fact that MouseUp is a routed event and letting it find the TreeViewItem parent for you. Instead of adding the event handler to the TreeView itself, add a MouseUp handler to the TreeViewItem, and it will always be called with a sender of the TreeViewItem.
You should also set your binding on IsExpanded to be two-way if it is not already. That way you can update IsExpanded on the TreeViewItem and the value will be pushed to the binding source.
In XAML:
<TreeView.ItemContainerStyle>
<Style TargetType="{x:Type TreeViewItem}">
<Setter Property="IsExpanded" Value="{Binding isExpanded, Mode=TwoWay}" />
<EventSetter Event="Mouse.MouseUp" Handler="tvi_MouseUp"/>
</Style>
</TreeView.ItemContainerStyle>
Then in code:
Private Sub tvi_MouseUp(ByVal sender As System.Object, ByVal e As MouseButtonEventArgs)
Dim tvi As TreeViewItem = DirectCast(sender, TreeViewItem)
If tvi.HasItems Then
tvi.IsExpanded = Not tvi.IsExpanded
End If
e.Handled = True
End Sub
Thank you, you are very kind. But unfortunately the problem is the same with your solution.
I omitted an important detail (sorry): when I expand a first-level TreeViewItem I add some second-level TreeviewItems. This causes the problem, if I don't add the items all works good.
I have edited my question, to make it more comprehensible.
Maybe now the solution is more easy (I hope).
Thanks,
Pileggi
Because of the changes I have done to my post I have thinked to open another thread. In the new thread I have posted my (provvisory) solution. You can find it here