I've created a custom user control that has several properties. One specifies which database I want the control to access. I want to be able to present the user of the control a drop down from which he can select which database the control will interact with.
How do I get the dropdown to work? I can get default values, but have yet to figure out how to get the selectable list.
Any help is apprectiated.
Thanks.
Marshall
You just need to attach your own TypeConverter to your property. You will override the GetStandardValuesSupported and GetStandardValues methods (maybe GetStandardValuesExclusive too) to return the list of databases you want to show.
If you are new to the PropertyGrid and the TypeConverter, here is a document.
It turns out to be simpler than I thought.
I had an enumeration set up for the property, but was having trouble using it for the property type. Said it was unaccessable outside of the class.
Then I had a 'duh' moment and changed the enumeration from Friend to Public, and then I was able to use the enumeration as the property type. As a result the values from the enumeration are listed in a dropdown when I look at the values for that property of the controls.
Thanks to all that answered.
Marshall
I'm a little confused about your problem.
If your user control contains a DropDownList control, just inititalize somewhere in the user control.
The easiest way is in the Codebehind for the usercontrol, just do DropDownList.Items.Add() or whatever the syntax is for adding an item.
Here is the template I use to create a custom datasource for my comboboxes:
Private Class Listing
Private _List As New ArrayList
Public Sub Add(ByVal ItemNumber As Integer, ByVal ItemName As String)
_List.Add(New dataItem(ItemNumber, ItemName))
End Sub
Public ReadOnly Property List() As ArrayList
Get
Return _List
End Get
End Property
End Class
Private Class dataItem
Private _ItemNumber As Integer
Private _ItemName As String
Public Sub New(ByVal intItemNumber As Integer, ByVal strItemName As String)
Me._ItemNumber = intItemNumber
Me._ItemName = strItemName
End Sub
Public ReadOnly Property ItemName() As String
Get
Return _ItemName
End Get
End Property
Public ReadOnly Property ItemNumber() As Integer
Get
Return _ItemNumber
End Get
End Property
Public ReadOnly Property DisplayValue() As String
Get
Return CStr(Me._ItemNumber).Trim & " - " & _ItemName.Trim
End Get
End Property
Public Overrides Function ToString() As String
Return CStr(Me._ItemNumber).Trim & " - " & _ItemName.Trim
End Function
End Class
And this is how I load it:
ListBindSource = New Listing
Me.BindingSource.MoveFirst()
For Each Row As DataRowView In Me.BindingSource.List
Dim strName As String = String.Empty
Dim intPos As Integer = Me.BindingSource.Find("Number", Row("Number"))
If intPos > -1 Then
Me.BindingSource.Position = intPos
strName = Me.BindingSource.Current("Name")
End If
ListBindSource.Add(Row("Number"), strName)
Next
cboNumber.DataSource = ListBindSource.POList
cboNumber.DisplayMember = "DisplayValue"
cboNumber.ValueMember = "Number"
AddHandler cboNumber.SelectedIndexChanged, AddressOf _
cboNumber_SelectedIndexChanged
Hope this helps. One thing to keep in mind is that if cboNumber has a handler already assigned to the SelectedIndexchanged event, you will encounter problems. So don't create a default event.
Related
I'm trying to link my ListBox to an ObservableCollection.
Here's my class for defining mods:
Public Class TroveMod
Private m_FileName As String
Private m_Enabled As Boolean
Public Property FileName() As String
Get
Return m_FileName
End Get
Set(value As String)
m_FileName = value
End Set
End Property
Public Property Enabled() As Boolean
Get
Return m_Enabled
End Get
Set(value As Boolean)
m_Enabled = value
End Set
End Property
Public ReadOnly Property ModName()
Get
Return Path.GetFileNameWithoutExtension(FileName)
End Get
End Property
End Class
And this is the actual Property ModList:
Public Property ModList() As ObservableCollection(Of TroveMod)
Get
Return m_ModList
End Get
Set(value As ObservableCollection(Of TroveMod))
m_ModList = value
End Set
End Property
I add items using:
Private Sub AddMod(file__1 As String, enabled As Boolean)
If File.Exists(file__1) Then
ModList.Add(New TroveMod() With { _
.FileName = file__1, _
.Enabled = enabled _
})
End If
End Sub
Everytime I want to add something to this Collection using AddMod, it won't show off in my listbox :/ I added an ModListBindingSource to the ListBox and set the DisplayMember and ValueMember to ModName but it still won't work. I also got a status label, which says, that it successful added the mods to the collection but it simply won't show them in the ListBox. Did I miss something?
An ObservableCollection is not quite what you want - this would allow your code to see changes to the collection via events. For instance, if there were several actors adding items to the collection and you wanted to know that. In this case, since 'local' code is adding items, it is not needed.
It is also not clear how the collection is mapped to the ListBox as the DataSource. Try this:
Public Class Form...
Private myList As New BindingList(Of TroveMod)
Sub Form_Load(....
theListBox.DataSource = myList
theListBox.DisplayMember = "ModName"
Now, as you add things to the BindingList they will appear in theListBox. If an item changes though (e.g. the Name), that change will not show up without a little more work, but as these are file names that seems unlikely.
The form property is not needed unless an external class also needs access to the collection/BindingList; in that case, you probably do not want need a setter.
I have a datagridview and a bindinglist. They work together pretty ok, but I want to make the properties appear in the rows, not on the column. Is there any way to achieve that ?
My code for anyone who is interested.
Public Class Form1
Dim listaBindingSource As New BindingList(Of pessoa)
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim b1 As New pessoa()
listaBindingSource.Add(b1)
dgv.DataSource = listaBindingSource
End Sub
End Class
Public Class pessoa
Dim sells_Month1 As String
Public Sub New() 'ByVal nome_fora As String)
sells_Month1 = "0"
End Sub
Property vendas1 As String
Get
Return sells_Month1
End Get
Set(value As String)
sells_Month1 = value
End Set
End Property
The other properties are vendas2, vendas3.. and are the same as this one.
Edit:
I´m kind of lost here. What I want is to make the values of the properties of my objects appear on some kind of data visualizer. When I add new objects on the list, they appear on this data visualizer and when I change the values of the cells there, the values of the properties change. Anyone has a good sugestion ? Apparentely dgv is not the way to go.
Thanks,
Ricardo S.
I want to make the properties appear in the rows´ headers, not on
the column.
I'm afraid this is not possible, there is no built-in solution for that in DataGidView. You can display the properties in columns only.
To control the text displayed in the column header, try to set the DisplayName attribut:
<System.ComponentModel.DisplayName("DisplayedText")>
Property vendas1 As String
Get
Return sells_Month1
End Get
Set(value As String)
sells_Month1 = value
End Set
End Property
Or if you import System.ComponentModel namespace.
<DisplayName("DisplayedText")>
Property vendas1 As String
Get
Return sells_Month1
End Get
Set(value As String)
sells_Month1 = value
End Set
End Property
How can we databind a datagridview to some of the My.Settings (user scoped) properties so the user can edit the values? This must be to a datagridview. I know we can bind to My.Settings in a form with textboxes and so on, but in this case we just want it as list of editable strings in a datagridview.
Of course some My.Settings entries can have different datatypes which complicates matters but generally we're only working with strings and booleans.
Also, let's assume the user understands that he must enter the string "true" to set a boolean to true. No checkbox column needed.
Here's what we are using (and it works), just looking for a better, leaner way:
here's the class:
Public Class MySettingsMaint
...
then we have a bindinglist (this is probably yuk):
Private list As BindingList(Of BindingKeyValuePair)
here's what the datagridview binds to:
Public ReadOnly Property DataSource() As Object
Get
list = New BindingList(Of BindingKeyValuePair)
list.Add(New BindingKeyValuePair("PhoneExtension", My.Settings.PhoneExtension.ToString.ToLower))
list.Add(New BindingKeyValuePair("PhonePIN", My.Settings.PhonePIN.ToString.ToLower))
list.Add(New BindingKeyValuePair("PhoneEnabled", My.Settings.PhoneEnabled.ToString.ToLower))
Return From k In list Order By k.Key
Return list
End Get
End Property
...
Public Sub LoadGrid(ByVal grd As DataGridView) Implements
/some stuff here to create two DataGridViewColumns
/one bound to Key, the other bound to Setting
End Sub
more yuk here, to save back to My.Settings:
Public Sub Save() Implements IMaintainable.Save
My.Settings.PhoneExtension = (From x As BindingKeyValuePair In list Where x.Key = "PhoneExtension" Select x.Value.ToLower).ToList(0)
My.Settings.PhonePIN = (From x As BindingKeyValuePair In list Where x.Key = "PhonePIN" Select x.Value.ToLower).ToList(0)
My.Settings.PhoneEnabled = (From x As BindingKeyValuePair In list Where x.Key = "PhoneEnabled" Select x.Value.ToLower).ToList(0) = "true"
My.Settings.Save()
End Sub
the private class required by the above class:
Private Class BindingKeyValuePair
Sub New(ByVal k As String, ByVal v As String)
Key = k
Value = v
End Sub
Private _Key As String
Public Property Key() As String
/basic getsetter
End Property
Private _Value As String
Public Property Value() As String
/basic getsetter
End Property
End Class
You should use the PropertyGrid control? It will help with regard to supporting richer property types.
I am trying to create a settings class.
The Property Test() is a list of strings.
When I add a string such as: t.test.Add("asasasAAAAA")
I want it to autmatically turn lowercase.
For some reason it is not. Any Ideas?
p.s.
using t.test.Add(("asasasAAAAA").ToLower) will not work for what I need.
Thank you.
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim t As New Settings
t.test.Add("asasasAAAAA")
t.test.Add("aBBBBBAAAAA")
t.test.Add("CCCCCsasAAAAA")
End Sub
End Class
Public Class Settings
Private strtest As New List(Of String)
Public Property test() As List(Of String)
Get
Return strtest
End Get
Set(ByVal value As List(Of String))
For i As Integer = 0 To value.Count - 1
value(i) = value(i).ToLower
Next
strtest = value
End Set
End Property
End Class
ashakjs
That's the reason: set accessor of your property is actually never called.
when you use t.test.Add("asasasAAAAA") you are actually calling a get accessor, which returns a list, after that specified string is added to this list, so .ToLower function is never called.
Simple way to fix this:
Dim list as New List(Of String)
list.Add("asasasAAAAA")
list.Add("aBBBBBAAAAA")
list.Add("CCCCCsasAAAAA")
t.test = list
Alternatively, you can implement your own string list (easiest way - inherit from Collection (Of String)), which will automatically convert all added string to lower case.
What you are trying to do and what you are doing don't match. To do what you want, you need to create your own collection class extending the generic collection - or provide a custom method on your settings class which manually adjusts the provided string before adding it to the local (private) string collection.
For an example of the second option, remove the public property of the settings class which exposes the list of string and use a method like the following:
Public Sub Add(ByVal newProp As String)
strtest.Add(newProp.toLower())
End Sub
I need to create a repeater section that will show 4 columns - First Name, Last Name, a link based off of stored column data that says.
All the data plus some extra not being used is in a players profile. How do I link the data on the code-behind to the repeater control with the databinders?
I am using visual studio 2008, VB.NET for the code behind.
Have you considered using a DataGrid instead of a repeater?
Here's a bit of a breakdown on when to use each.
http://msdn.microsoft.com/en-us/library/aa479015.aspx
To more directly answer your question you'll need to set the Repeater's DataSource property to a DataView or an ArrayList. As such:
Sub Page_Load(Sender As Object, e As EventArgs)
If Not IsPostBack Then
Dim values As New ArrayList()
values.Add(New PositionData("Microsoft", "Msft"))
values.Add(New PositionData("Intel", "Intc"))
values.Add(New PositionData("Dell", "Dell"))
Repeater1.DataSource = values
Repeater1.DataBind()
Repeater2.DataSource = values
Repeater2.DataBind()
End If
End Sub
Public Class PositionData
Private myName As String
Private myTicker As String
Public Sub New(newName As String, newTicker As String)
Me.myName = newName
Me.myTicker = newTicker
End Sub
Public ReadOnly Property Name() As String
Get
Return myName
End Get
End Property
Public ReadOnly Property Ticker() As String
Get
Return myTicker
End Get
End Property
End Class