Public Class Apple
Private d_isplayName As String
Public Property DisplayName() As String
Get
Return d_isplayName
End Get
Set(ByVal value As String)
d_isplayName = value
End Set
End Property
Private u_niqueVal As String
Public Property uniqueVal() As String
Get
Return u_niqueVal
End Get
Set(ByVal value As String)
u_niqueVal = value
End Set
End Property
End Class
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim RedApple As New Apple With {.DisplayName = "redapple", .uniqueVal = "Uval"}
tsiAddFruit.DropDownItems.Add("Some Text", Nothing, AddressOf fruit_Click)' Work fine
tsiAddFruit.DropDownItems.Add(RedApple, Nothing, AddressOf fruit_Click)' does not work
End Sub
Private Sub fruit_Click(sender As System.Object, e As System.EventArgs)
Dim MenuItem As ToolStripMenuItem = DirectCast(sender, ToolStripMenuItem)
MessageBox.Show(MenuItem.Text)
End Sub
How can I pass an object in ToolStripMenuItem without using the .Tag property(no third-party tool too)? I want to use Apple.DisplayName and the display value and Apple.UniqueVal as the value type.
Related
What should I add to a custom class so it works with System.Windows.Forms.Listbox.Items.Contains()..?
I've created a class called "FileItem" for handling filenames in ListBoxes. It works as expected, but if I try to use ListBox.Items.Contains() to prevent duplicate items from being added, nothing happens. The Contains() function never returns True.
Here's the code. Add it to a VB.Net form named frmTest with a ListBox1, Button1, and Button2. Run it and press Button1 multiple times. The duplicate warning message is never displayed.
Public Class frmTest
Private Sub frmTest_Load(sender As Object, e As EventArgs) Handles Me.Load
With ListBox1
.DisplayMember = "ShortName"
.ValueMember = "LongName"
End With
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim f As FileItem = New FileItem("C:\Windows\Notepad.exe")
If ListBox1.Items.Contains(f) Then
MsgBox("The file is already added and will be skipped.")
Else
ListBox1.Items.Add(f)
End If
f = Nothing
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
Dim msg As String = ""
For Each item As FileItem In ListBox1.Items
msg &= item.FullName & vbCr
Next
MsgBox(msg)
End Sub
Private Class FileItem
Private ReadOnly _FullName As String
Private ReadOnly _ShortName As String
Public Sub New(ByVal FullName As String)
_FullName = FullName
If FullName.Contains("\") Then
Dim pos As Integer = FullName.LastIndexOf("\")
_ShortName = FullName.Substring(pos + 1)
End If
End Sub
Public ReadOnly Property FullName() As String
Get
Return _FullName
End Get
End Property
Public ReadOnly Property ShortName() As String
Get
Return _ShortName
End Get
End Property
Public Overrides Function ToString() As String
Return _FullName
End Function
End Class
End Class
I have created a custom control (Check Box) with a custom EventHandler
Public Event CheckedChanged As EventHandler
Private Sub setCheckStateUI(sender As Object, e As EventArgs)
...
RaiseEvent CheckedChanged(sender, e)
End Sub
It works fine without any errors if I added this control directly to a form. But when I add this to another custom control (a page of settings window) and that second custom control add to a form (settings window) the 'settings window' freeze and visual studio auto restart.
If I removed this event handler in the code the problem is gone.
What can be the problem here?
Thanks in advance
Update: (Complete code of the Custom Control)
Public Class cusCheckBox
Private mystring As String
Private CheckButtonState As Integer = 0
Public Event CheckedChanged As EventHandler
Public Sub New()
' This call is required by the designer.
InitializeComponent()
' Add any initialization after the InitializeComponent() call.
mystring = Me.Name
setSizes()
End Sub
Public Property CheckState() As Integer
Get
CheckState = CheckButtonState
End Get
Set(ByVal value As Integer)
CheckButtonState = value
chkButton.CheckState = CheckButtonState
End Set
End Property
Public Property LabelText() As String
Get
LabelText = mystring
End Get
Set(ByVal value As String)
mystring = value
lblText.Text = mystring
setSizes()
End Set
End Property
Public Overrides Property Font As Font
Get
Return lblText.Font
End Get
Set(value As Font)
lblText.Font = value
End Set
End Property
Private Sub chkButton_CheckedChanged(sender As Object, e As EventArgs) Handles chkButton.CheckedChanged
If chkButton.CheckState = 1 Then
chkButton.Image = Global.MYLogs.My.Resources.Resources.btnToggleOn
CheckButtonState = 1
Else
chkButton.Image = Global.MYLogs.My.Resources.Resources.btnToggleOff
CheckButtonState = 0
End If
End Sub
Private Sub lblText_Click(sender As Object, e As EventArgs) Handles lblText.Click
setCheckStateUI(sender, e)
End Sub
Private Sub cusCheckBox_MouseClick(sender As Object, e As MouseEventArgs) Handles Me.MouseClick
setCheckStateUI(sender, e)
End Sub
Private Sub cusCheckBox_Load(sender As Object, e As EventArgs) Handles MyBase.Load
setCheckStateUI(sender, e)
setSizes()
End Sub
Private Sub cusCheckBox_Resize(sender As Object, e As EventArgs) Handles Me.Resize
setSizes()
End Sub
Private Sub setSizes()
Me.Size = New Size(chkButton.Width + lblText.Width + 4, chkButton.Height)
End Sub
Private Sub setCheckStateUI(sender As Object, e As EventArgs)
If chkButton.CheckState = 0 Then
chkButton.Image = Global.MYLogs.My.Resources.Resources.btnToggleOn
chkButton.CheckState = 1
CheckButtonState = 1
Else
chkButton.Image = Global.MYLogs.My.Resources.Resources.btnToggleOff
chkButton.CheckState = 0
CheckButtonState = 0
End If
RaiseEvent CheckedChanged(Me, EventArgs.Empty)
chkButton.Select()
End Sub
End Class
I have a class with a bindinglist(of T) in it. The bindinglist is bound to a datagridview on my form. When items are added to the bindinglist, they show up in the datagridview however the scrollbar never changes to accommodate for the new data. I am starting to think this is because the Listchanged event isn't being fired (or properly captured by my form). I have my code set up like this:
Data Class:
Public Class data
Implements INotifyPropertyChanged
Public Sub new(byVal att1 as string, ByVal att2 as string)
Attribute1 = att1
Attribute2 = att2
End sub
Private mAttribute1 as string
Public Property Attribute1 as string
Get
return mAttribute1
End get
Set(ByVal value as string)
mAttribute1 = value
OnPropertyChanged("Attribute1")
End Set
End Property
Private mAttribute2 as string
Public Property Attribute2 as string
Get
return mAttribute2
End Get
Set(ByVal value as string)
mAttribute2 = value
OnPropertyChanged("Attribute2")
End Set
End Property
Public Sub OnPropertyChanged(ByVal name As String)
RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(name))
End Sub
Public Sub ChangeDataFormat()
'change from one format to the other
End Sub
End Class
Data Generator Class:
Public Class dataGenerator()
private myThread as New System.Theading.Thread(address of StartDataGeneration)
Public Sub new()
mDataList = new bindingList(of Data)
mDataList.RaiseListChangedEvents = True
Private WithEvents mDataList as bindingList(Of Data)
Public readonly DataList as bindingList(of Data)
Get
Return mDataList
End Get
End property
Private Sub StartDataGeneration()
dim att1 as integer = 1
dim att2 as integer = 2
for i as Integer = 0 to 1000
mDataList.Insert(0,New Data(att1.ToString,att2.ToString)
att1 *= 2
att2 *=3
next
End Sub
Public Sub StartDataThread()
myThread.Start()
End Sub
Public Sub ChangeDataFormat()
for each d as data in mDataList
d.ChangeDataFormat()
next
End Sub
End Class
Form:
Public class Form1
Private myGenerators as new BindingList(of dataGenerator)
Private myDataGrids as new BindingList(of DataGridView)
Private Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Mybase.Load
dim NumberOfGenerators as integer = Convert.ToInt32(My.Settings.CraneCount)
for i as integer = 1 to NumberOfGenerators
Dim newGenerator As New DataGenerator()
Dim newTab as Ne tabPage(i.ToString)
Dim NewGrid as New DataGridView
newTab.Controls.Add(newGrid)
newGrid.DataSource = newGenerator.DataList
myGenerators.Add(newGrid)
next
End Sub
Private Sub ButtonStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonStart.Click
for each generator as dataGenerator in myGenerators
generator.StartDataThread()
next
End Sub
Private Sub ButtonChangeFormat_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonChangeFormat.Click
for each generator as dataGenerator in myGenerators
generator.ChangeDataFormat()
next
End Sub
End Class
I know that there is a lot of code but I wanted to be clear. So when I click the start button the new items start appearing, however, once they get to the bottom of the grid the scroll bar doesn't appear. If I click the Change Format button the data changes format and updates in the grid properly. I was under the impression that the ListChanged event would automatically work with a bindinglist and datagridview. I tried calling update and refresh on myDataGridView and setting datagridview.datasource to nothing and then back to DataList.
Am I missing something?
I would like to move Item objects between the 2 following collections.
Private ItemsInRoom As New List(Of CItem)
Private Inv As New List(Of CItem)
I would like this to be done through 2 ListBoxes. 1 is the Inventory and the other is the Item list. How can I do this.
The CItem class has several members, only the Name of the item needs to be shown in the ListBox. I have been at this for hours, but I can't get anything to work. Does this explanation make sense in what I'm trying to do? If not, what else can I explain so someone might help me?
In your CItem class you need to override the ToString() function. That will get the name displayed in the listbox.
Public Class CItem
Public Overrides Function ToString() As String
Return Me.Name
End Function
'etc...
End Class
I think what you want is this:
Which is accomplished with the following code:
Option Explicit On
Public Class Form1
Private ItemsInRoom As New List(Of CItem)
Private ItemsInInv As New List(Of CItem)
Protected Overrides Sub OnLoad(ByVal e As System.EventArgs)
MyBase.OnLoad(e)
ItemsInInv.Add(New CItem(1001, "Egret"))
ItemsInInv.Add(New CItem(1002, "Dove"))
ItemsInInv.Add(New CItem(1003, "Hawk"))
UpdateBindings()
End Sub
Public Function CheckOut(ByVal item As CItem) As Boolean
If item IsNot Nothing Then
ItemsInInv.Remove(item)
ItemsInRoom.Add(item)
Return True
End If
Return False
End Function
Public Function CheckIn(ByVal item As CItem) As Boolean
If item IsNot Nothing Then
ItemsInRoom.Remove(item)
ItemsInInv.Add(item)
Return True
End If
Return False
End Function
Public Sub UpdateBindings()
itemsInInvListBox.BeginUpdate()
itemsInInvListBox.DataSource = Nothing
itemsInInvListBox.DataSource = ItemsInInv
itemsInInvListBox.DisplayMember = "Name"
itemsInInvListBox.EndUpdate()
itemsInInvListBox.Refresh()
itemsInRoomListBox.BeginUpdate()
itemsInRoomListBox.DataSource = Nothing
itemsInRoomListBox.DataSource = ItemsInRoom
itemsInRoomListBox.DisplayMember = "Name"
itemsInRoomListBox.EndUpdate()
itemsInRoomListBox.Refresh()
End Sub
Private Sub itemsInInvListBox_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles itemsInInvListBox.SelectedIndexChanged
checkOutButton.Enabled = itemsInInvListBox.SelectedIndex <> -1
End Sub
Private Sub itemsInRoomListBox_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles itemsInRoomListBox.SelectedIndexChanged
checkInButton.Enabled = itemsInRoomListBox.SelectedIndex <> -1
End Sub
Private Sub checkOutButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles checkOutButton.Click
Dim item As CItem = CType(itemsInInvListBox.SelectedItem, CItem)
If CheckOut(item) Then
UpdateBindings()
End If
End Sub
Private Sub checkInButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles checkInButton.Click
Dim item As CItem = CType(itemsInRoomListBox.SelectedItem, CItem)
If CheckIn(item) Then
UpdateBindings()
End If
End Sub
End Class
Public Class CItem
Public Sub New(ByVal item_id As UInteger, ByVal item_name As String)
Me.m_id = item_id
Me.m_name = item_name
End Sub
Private m_name As String
Public Property Name() As String
Get
Return m_name
End Get
Set(ByVal value As String)
m_name = value
End Set
End Property
Private ReadOnly m_id As UInteger
Public ReadOnly Property ID() As UInteger
Get
Return m_id
End Get
End Property
End Class
I have a class being populated from comma separated rows in a text file.
I am trying to have the name property of each object appear in a listbox, then have the rest of the properties of a selected object show up in text boxes. How do I load the properties of the selected object to the correct textbox?
I'm assuming that the class you fill has a list of the objects and that you have already figured out how to fill the listbox...
Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged
For Each obj As YourObjectType In YourClass.CollectionOfYourObjects
If obj.Name = ListBox1.SelectedItem.ToString Then
Textbox1.Text = obj.Property1
Textbox2.Text = obj.Property2
End If
Next
End Sub
You have one TextBox for every Property and the number of properties is static, isn't it?
You have to set the DisplayMember to the Property's name that you want to see in the Listbox.
This simplified sample should work:
Public Class ListBox
Private Sub ListBox_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim allFoos As New List(Of FooClass)
For i As Int32 = 1 To 10
Dim foo As New FooClass
foo.Name = "Foo_" & i
foo.Prop1 = "Prop1_" & i
foo.Prop2 = "Prop2_" & i
foo.Prop3 = "Prop3_" & i
allFoos.Add(foo)
Next
Me.ListBox1.DataSource = allFoos
Me.ListBox1.DisplayMember = "Name"
End Sub
Private Sub ListBox1_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged
Dim foo As FooClass = DirectCast(ListBox1.SelectedItem, FooClass)
Me.TxtName.Text = foo.Name
Me.TxtProp1.Text = foo.Prop1.ToString
Me.TxtProp2.Text = foo.Prop2.ToString
Me.TxtProp3.Text = foo.Prop3.ToString
End Sub
End Class
Class FooClass
Private _name As String
Private _prop1 As Object
Private _prop2 As Object
Private _prop3 As Object
Public Property Name() As String
Get
Return _name
End Get
Set(ByVal value As String)
_name = value
End Set
End Property
Public Property Prop1() As Object
Get
Return _prop1
End Get
Set(ByVal value As Object)
_prop1 = value
End Set
End Property
Public Property Prop2() As Object
Get
Return _prop2
End Get
Set(ByVal value As Object)
_prop2 = value
End Set
End Property
Public Property Prop3() As Object
Get
Return _prop3
End Get
Set(ByVal value As Object)
_prop3 = value
End Set
End Property
End Class