I have a usercontrol form named "ucSETTINGS", where there is a textbox and once the button was clicked, the text inside the textbox will be added to the combobox from another usercontrol form name "ucITEMS"
I tried this code but it's not working
(cboCategory is the name of the combobox from ucITEMS, txtNAME is the textbox from ucSETTINGS)
Private Sub btnSAVE_Click(sender As Object, e As EventArgs) Handles btnSAVE.Click
Dim category As New ucITEMS()
category.cboCATEGORY.Items.Add(txtNAME.Text)
End Sub
Can someone help me?
In this sort of situation, the user controls don't know about each other by default and it should stay that way. The source UC just exposes an interface and lets whomever is watching use that as it sees fit. That means raising an event when something happens and exposing required data via properties, e.g.
Public Class SourceControl
Public ReadOnly Property TextBox1Text As String
Get
Return TextBox1.Text
End Get
End Property
Public Event Button1Click As EventHandler
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
OnButton1Click(EventArgs.Empty)
End Sub
Protected Overridable Sub OnButton1Click(e As EventArgs)
RaiseEvent Button1Click(Me, e)
End Sub
End Class
The Text of the TextBox is exposed via a property and, when the user clicks the Button, the UC raises an event.
The destination UC provides an interface for new items to be provided but it adds them to its own ComboBox, e.g.
Public Class DestinationControl
Public Sub AddItemToComboBox1(item As Object)
ComboBox1.Items.Add(item)
End Sub
End Class
The form then plays go-between, handling the event, getting the property and calling the method:
Private Sub SourceControl1_Button1Click(sender As Object, e As EventArgs) Handles SourceControl1.Button1Click
DestinationControl1.AddItemToComboBox1(SourceControl1.TextBox1Text)
End Sub
Obviously you would use something more specific and appropriate than my generic naming.
Related
I'm trying to pass a value from one form, let's call it Form1 to another form, Form2. When i double click a row in a listview that is in Form2, the value should be passed to a combobox in Form1.
I could get one of my other forms to do this using an event called PropertyChanged, but I can't seem to get it to work on other forms. I don't know if it is the fact that you can only have 1 event in the entire project and not have another with the same name. I'm missing something, but i just don't know where.
This is the code i used in Form2:
Public Event PropertyChanged As Action(Of Object)
Private Sub ListView2_DoubleClick(sender As Object, e as EventArgs) Handles ListView2.DoubleClick
RaiseEvent PropertyChanged(ListView1.SelectedItems(0).SubItems(0).Text)
End Sub
And this is the code I used in Form1:
Dim WithEvents f2 As Form2
Private Sub PropertyChanged(obj As Object) Handles f2.PropertyChanged
cmb_form1.Text = obj
End Sub
There are several ways to implement this. This one is quick and dirty.
It consists of writing up a property in Form2 which is public. When the user makes a choice, it goes in the property. Then Form1 reads the property before it disposes Form2.
Here's a little code snippet to better illustrate what I mean:
Public Class Form1
' This form has a button which opens a Form2 instance
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim form2 As New Form2 ' instantiate Form2
form2.ShowDialog() ' the user chooses a value
MessageBox.Show(form2.Result) ' get it before it's out of scope!
End Sub
End Class
Public Class Form2
Public Property Result As String ' the value is stored in there, it can be any type
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Result = "Clicked!" ' store the value you want to share between forms
Me.Close()
End Sub
End Class
Have fun!
I have a form (frmwizard) which I am using to create a wizard like interface. The form contains a usercontrol and a button (for testing). There is also a function on the form called "NextPage"
The form loads a usercontrol (ucpage1) on load and the usercontrol has a button on it that when clicked attempts to call a function on the main form as per below:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
frmWizard.Nextpage(me.name)
End Sub
Within my function called "NextPage" have the following for testing.
Public Sub NextPage(ByVal CurrentPage As String)
MessageBox.Show(UserControl1.Controls.Count)
End Sub
When I call the function from the form itself (via the button) I get the result of 1, when i call the function via the User Control, I get the result as 0
I'm sure there is something simple I need to do, but i'm unsure what i've overlooked.
I am trying to make the button on the user-control Save the data within the control and then to browse to the next wizard page. Hopefully this is enough information
Codependance is a bad idea, as it locks the two types together for the future. If your user control really needs to invoke the form, you should instead have it raise an event and handle the event in your form.
Public Class MyUserControl
Public Event OnNextPage(ByVal sender As Object, ByVal e As EventArgs)
Private Sub btnNextPage_Click(sender As Object, e As EventArgs) Handles btnNextPage.Click
RaiseEvent OnNextPage(Me, New EventArgs)
End Sub
End Class
Public Class Form1
Private Sub MyUserControl_OnNextPage(sender As Object, e As EventArgs) Handles MyUserControl1.OnNextPage ' , MyUserControl2.OnNextPage, etc...
MessageBox.Show(DirectCast(sender, MyUserControl).Controls.Count)
End Sub
End Class
I need help to call a function in a usercontrol that is shown in a panel within the form, so far this is i tried, but no luck, i can't still get the text inputted on the textbox
Public Class Form1
Private Sub LinkLabel1_LinkClicked(ByVal sender As System.Object, ByVal e As System.Windows.Forms.LinkLabelLinkClickedEventArgs) Handles LinkLabel1.LinkClicked
Dim ustudent As New StudentAdd
ustudent.Dock = DockStyle.Fill
SplitContainer1.Panel2.Controls.Add(ustudent)
End Sub
Private Sub ToolStripButton1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ToolStripButton1.Click
ustudent.SaveData()
End If
End Sub
End Class
in user control have some textbox
textbox1 and textbox2
Public Class StudentAdd
Public Sub SaveData() As Boolean
'just testing whether it could work well
' getting textbox value
MsgBox(TextBox1.Text)
End Sub
End Class
But ustudent is a local var, try to declare it outside link_clicked event. Do you want to create multiple user controls in the win or just one?
For one you could add it at design time by dragging from the your project components panel
For more, you should implement some logic to identify the selected component and make it available for save data. If you want to save all just enumerate components in Panel2 (of type StudentAdd) and call the method
Soon I asked for help to read properties of textbox which is inside usercontrol.
Accessing to control inside of usercontrol
As I have been suggested I make one very simple public class with name xTextBox and use it as textbox in my usercontrol. That work fine.
Public Class xTextBox
Inherits TextBox
End Class
Now I can simply read a property on that xTextbox from main program which contain that usercontrol:
Dim s As Integer = myUserControl.xTextBox1.SelectionStart
But now is a problem that I can't get events of that Textbox in main program.
Maybe I can declare 'Shadows Event TextChanged...' etc, but I will need more events in different situations where usercontrol would be, and intentionally raising every of them don't look elegant in mean of practical programming.
How to get events of those xTextbox to main program?
If the your new UserControl has only one control and Inherits TextBox, then you can just attach the events like normal, either with the Property Editor, or Manually with AddHandler. If things are more complicated than that I would probably create a panel and put your new TextBox's in it, then it will be a lot easier to access the events.
Public Class myUserControl
Inherits TextBox
End Class
Public Class Form1
Public Sub New()
InitializeComponent()
AddHandler MyUserControl1.TextChanged, AddressOf MyUserControl_textChanged
End Sub
Private Sub MyUserControl_textChanged(sender As Object, e As EventArgs)
Throw New NotImplementedException
End Sub
End Class
Or if your UserControl has Multiple Custom TextBox's in it, you can create a Custom Event and fire that in a common TextChanged Event on your UserControl and handle that in your Main Form.
Public Class UserControl1
Public Event TextChange(sender As Object, e As EventArgs)
Private Sub MyUserControl_TextChanged(sender As System.Object, e As System.EventArgs) Handles MyUserControl1.TextChanged, MyUserControl2.TextChanged
RaiseEvent TextChange(sender, e)
End Sub
End Class
Public Class Form1
Public Sub New()
InitializeComponent()
End Sub
Private Sub UserControl11_TextChange(sender As System.Object, e As System.EventArgs) Handles UserControl11.TextChange
MsgBox(CType(sender, TextBox).Name, MsgBoxStyle.Information)
End Sub
End Class
I have a class A which contains 2 user controls declared as
Friend WithEvents CustInfo1 As WindowsApplication1.CustInfo
Friend WithEvents ServiceLocation1 As WindowsApplication1.ServiceLocation
Both have textBoxes. If value of textBoxA in custInfo1 changes then how can I make value of textBoxB in SeviceLocation1 also change
I will be most thankful if anyone can help me.
Thanks
You need to do the following:
Inside the CustInfo user control, you need to write code inside the textBoxA Changed event that raises an event from the CustInfo user control (e.g. TextBoxChanged event). RaiseEvent statement
Inside the ServiceLocation user control, create a public property getter and setter for whatever your textBoxB.Text is
On the form that contains both user controls, create code in the new CustInfo TextBoxChanged event and set the new property on the ServiceLocation1 user control.
All controls (also custom controls) have the property Controls, through which you can access the (sub) controls of that control. Now you can retrieve your textbox by calling the .Item(key) method on it. Then you can assign a event handler to it in your form or class.
Dim key As String = "textBoxA" 'Or simply the name of that TextBox in your CustInfo
Dim textboxA As TextBox = CustInfo1.Controls.Item(key)
AddHandler textBoxA.TextChanged, AddressOf mytextchangedhandler
Where that mytextchangedhandler handles the TextChanged event for that TextBox.
Personally I don't like this method too much, as you are relying on knowing either the name of the TextBox or the index in the Controls list of your usercontrol.
I would definitely go for the option to create your own event on your usercontrol. It is quite easy to do even! Below how to do it. In the code behind of your usercontrol, you'll have to add an event declaration:
Event MyTextBoxChanged(sender As Object, e As EventArgs)
Now we'll have to raise it, we do this by implementing the TextChanged event of the TextBoxA in your usercontrol (as you explained you wanted to do):
Private Sub TextBoxA_TextChanged(sender As System.Object, e As System.EventArgs) Handles TextBoxA.TextChanged
RaiseEvent MyTextBoxChanged(Me, EventArgs.Empty)
End Sub
Now we can simply implement this event (MyTextBoxChanged) in your Form as follows:
Private Sub CustInfo1_MyTextBoxChanged(sender As System.Object, e As System.EventArgs) Handles CustInfo1.MyTextBoxChanged
' Do something
End Sub
Obviously we still need to get the updated text, now we can create our own EventArgs that will give us the new (and/or old value) as you will want to have. We simply can inherit the System.EventArgs class and add some properties (for example a property OldText that holds the old text value and a property NewText that holds the new text value):
Public Class MyEventArgs
Inherits System.EventArgs
Private _OldText As String
Public ReadOnly Property OldText() As String
Get
Return _OldText
End Get
End Property
Private _NewText As String
Public ReadOnly Property NewText() As String
Get
Return _NewText
End Get
End Property
Public Sub New(oldText As String, newText As String)
_OldText = oldText
_NewText = newText
End Sub
End Class
Now we have to change the event definition and raising to use the MyEventArgs:
Event MyTextBoxChanged(sender As Object, e As MyEventArgs)
Private Sub TextBoxA_TextChanged(sender As System.Object, e As System.EventArgs) Handles TextBoxA.TextChanged
RaiseEvent MyTextBoxChanged(Me, New MyEventArgs(TextBoxA.Text))
End Sub
And also change the implementation in your Form:
Private Sub CustInfo1_MyTextBoxChanged(sender As System.Object, e As MyEventArgs) Handles CustInfo1.MyTextBoxChanged
MessageBox.Show(e.Text)
End Sub
More information about events can be found on our favorite spot MSDN.