Access in UserControl Member's Properties - vb.net

I create a UserControl with three Panels
I add this UserControl in my main Form but i have then the problem that i can't choose which panel to appear in my main form.
Exccactly i have this code below to make visible my Panel1
Public Function Pan1()
Panel3_Paint.Visible = False
Panel2_Paint.Visible = False
Panel1_Paint.Visible = True
Return 0
End Function
So after i click in a stripMenu i tried to appear the first panel with this function in my Form but finally in my main Form appears the third Panel.
i use my function in this way
Private Sub ClassAToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ClassAToolStripMenuItem.Click
UserControl11.Visible = True
Call Pan1()
End Sub`
I try when i click a specific button in menu to show the appropriate panel
That's why i try to do it with this function but i have the problem that in my form appears only the third panel.
My UserControl Code
Public Class UserControl1
Public Sub Panel3_Paint(sender As Object, e As PaintEventArgs) Handles Panel3.Paint
End Sub
Public Sub Panel2_Paint(sender As Object, e As PaintEventArgs) Handles Panel2.Paint
End Sub
Public Sub Panel1_Paint(sender As Object, e As PaintEventArgs) Handles Panel1.Paint
End Sub
End Class
I define also my UserControl and Panels in my Form.vb this way
Public UserControl1 As New UserControl
Public Panel1_Paint As New Panel
Public Panel2_Paint As New Panel
Public Panel3_Paint As New Panel

Without seeing more of your code, I am assuming there may be an issue with the call of the function.
Make sure the function is called in an event. For example, if you add a CommandButton to the Form, you can add the following code to run in case of a click on the button:
Private Sub CommandButton1_Click()
Call Pan1
End Sub
I hope this helps.

So my problem is solved. I can't access in Panel Properties, that's why i create a Public Sub in my UserControl.vb and use it in my Form.
This code is written in my UserControl.vb
Public Sub Pan1()
Panel3_Paint.Visible = False
Panel2_Paint.Visible = False
Panel1_Paint.Visible = True
End Function
And then i call my Sub in my Form in this way
Private Sub ClassAToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ClassAToolStripMenuItem.Click
UserControl11.Visible = True
UserControl11.Pan1()
End Sub

Related

Add combobox items from another usercontrol form using textbox

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.

declared event which fires, but is not heard

I have a vb.net application which contains two forms. One is called "MapComponentForm" and another called "ComponentPropertiesForm". In the MapComponentForm I have defined an event which I want fired when the OK button is clicked. If the ComponentPropertiesForm is open, I want it to "hear" this event and act accordingly. Stepping through the code the event seems to fire as expected but the ComponentPropertiesForm seems to be oblivious to this. I've attached the code from the two forms after stripping out the non relevant code in hopes that someone can tell me why my event goes unheeded. I used the information here:
https://learn.microsoft.com/en-us/dotnet/visual-basic/programming-guide/language-features/events/walkthrough-handling-events
in constructing my own code.
Thanks for any suggestions.
Public Class MapComponentForm
Public Event PartMapped(ByRef status As Boolean)
Public Sub New(shape As Visio.Shape)
' This call is required by the designer.
InitializeComponent()
' Add any initialization after the InitializeComponent() call.
_shape = shape
End Sub
Private Sub OkButton_Click(sender As Object, e As EventArgs) Handles OkButton.Click
'If the component properties window is open, refresh it
If Application.OpenForms().OfType(Of ComponentPropertiesForm).Any Then
RaiseEvent PartMapped(True)
End If
end sub
end class
Public Class ComponentPropertiesForm
Private WithEvents mPartMap As MapComponentForm
Private Sub ComponentPropertiesForm_Load(sender As Object, e As EventArgs) Handles Me.Load
mPartMap = New MapComponentForm(Nothing)
End Sub
Private Sub mPartMap_PartMapped(ByRef status As Boolean) Handles mPartMap.PartMapped
If status = True Then
MsgBox("something got mapped")
End If
End Sub
end class

CefSharp inside a Control

When I attempt to add CefSharp to a Panel or Groupbox it doesn't display anything (by that I mean that the webbrowser doesn't show, even a blank page, only the control background is visible as if there is nothing added).
But when I use "Me" instead, it works normally. Why is that? Is it not possible to add it to wherever you want?
Public Class Form_Main
Private WithEvents chromeBrowser As ChromiumWebBrowser
Public Sub InitializeChromium()
InitializeComponent()
Dim CEF_settings As New CefSettings With {
.CachePath = "Cache"
}
CefSharp.Cef.Initialize(CEF_settings)
chromeBrowser = New ChromiumWebBrowser("www.google.com") With {
.Dock = DockStyle.Fill
}
Panel1.Controls.Add(chromeBrowser) 'With Me.Controls.Add(chromeBrowser) it works
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
InitializeChromium()
End Sub
End Class
I don't know why, but changing the Method name to "New" fixes it.
So instead of
Public Sub InitializeChromium()
'Stuff"
End Sub
it must be
Public Sub New()
'Stuff"
End Sub
Now the webbrowser gets displayed no matter where it's placed.
At your Program, You must not to use InitializeComponent().
Remove it from all of the codes.

How to call a Sub without knowing which form is loaded into panel?

On every DataGridView1_SelectionChanged event I need to run a Private Sub OnSelectionChanged() of the form that is loaded into Panel1 (see the image http://tinypic.com/r/2nu2wx/8).
Every form that can be loaded into Panel1 has the same Private Sub OnSelectionChanged() that initiates all the necessary calculations. For instance, I can load a form that calculates temperatures or I can load a form that calculates voltages. If different element is selected in the main form’s DataGridView1, either temperatures or voltages should be recalculated.
The problem is - there are many forms that can be loaded into Panel1, and I’m struggling to raise an event that would fire only once and would run the necessary Sub only in the loaded form.
Currently I’m using Shared Event:
'Main form (Form1).
Shared Event event_UpdateLoadedForm(ByVal frm_name As String)
'This is how I load forms into a panel (in this case frm_SCT).
Private Sub mnu_SCT_Click(sender As Object, e As EventArgs) Handles mnu_SCT.Click
frm_SCT.TopLevel = False
frm_SCT.Dock = DockStyle.Fill
Panel1.Controls.Add(frm_SCT)
frm_SCT.Show()
Var._loadedForm = frm_SCT.Name
RaiseEvent event_UpdateLoadedForm(Var._loadedForm)
End Sub
‘Form that is loaded into panel (Form2 or Form3 or Form4...).
Private WithEvents myEvent As New Form1
Private Sub OnEvent(ByVal frm_name As String) Handles myEvent.event_UpdateLoadedForm
‘Avoid executing code for the form that is not loaded.
If frm_name <> Me.Name Then Exit Sub
End Sub
This approach is working but I’m sure it can be done way better (I'd be thankful for any suggestions). I have tried to raise an event in the main form like this:
Public Event MyEvent As EventHandler
Protected Overridable Sub OnChange(e As EventArgs)
RaiseEvent MyEvent(Me, e)
End Sub
Private Sub DataGridView1_SelectionChanged(sender As Object, e As EventArgs) _
Handles DataGridView1.SelectionChanged
OnChange(EventArgs.Empty)
End Sub
but I don't know to subscribe to it in the loaded form.
Thank you.
Taking into account Hans Passant’s comments as well as code he posted in related thread I achieved what I wanted (see the code below).
Public Interface IOnEvent
Sub OnSelectionChange()
End Interface
Public Class Form1
' ???
Private myInterface As IOnEvent = Nothing
' Create and load form.
Private Sub DisplayForm(frm_Name As String)
' Exit if the form is already displayed.
If Panel1.Controls.Count > 0 AndAlso _
Panel1.Controls(0).GetType().Name = frm_Name Then Exit Sub
' Dispose previous form.
Do While Panel1.Controls.Count > 0
Panel1.Controls(0).Dispose()
Loop
' Create form by its full name.
Dim T As Type = Type.GetType("Namespace." & frm_Name)
Dim frm As Form = CType(Activator.CreateInstance(T), Form)
' Load form into the panel.
frm.TopLevel = False
frm.Visible = True
frm.Dock = DockStyle.Fill
Panel1.Controls.Add(frm)
' ???
myInterface = DirectCast(frm, IOnEvent)
End Sub
Private Sub DataGridView1_SelectionChanged(sender As Object, e As EventArgs) _
Handles DataGridView1.SelectionChanged
' Avoid error if the panel is empty.
If myInterface Is Nothing Then Return
' Run subroutine in the loaded form.
myInterface.OnSelectionChange()
End Sub
End Class
One last thing – it would be great if someone could take a quick look at the code (it works) and confirm that it is ok, especially the lines marked with “???” (I don’t understand them yet).

One button to control another button on many user controls

Hey and sorry for another strange question...
I have 25 UserControls with a Start_Button on each of them - this Start_Button can either be Visible or not depending on whether the UserControl is active. On my form1 I have a Start_All button.
I would like to simulate a click of all the UserControl's Start_Buttons which are visible only.
Instead of simulating click-events expose a method for the start-functionality and call this method from the Start_Button.Click-event. Then you can use this method from wherever you want. On this way your code remains readable and reusable.
You should also provide an Active property in your UserControl which you can simply link to your start-button's Visible-property.
Presuming that the user-controls are in a container-control like Panel:
Public Sub StartAll()
Dim allActiveUserControls =
From uc In controlPanel.Controls.OfType(Of MyUserControlType)()
Where uc.Active
For Each uc In allActiveUserControls
uc.Start()
Next
End Sub
Here is an example for the Active property:
Public Property Active As Boolean
Get
Return StartButton.Visible
End Get
Set(value As Boolean)
StartButton.Visible = value
End Set
End Property
and here are the Start method and the event-handlers:
Public Sub Start()
' Do Something ... '
End Sub
Private Sub StartButton_Click(sender As System.Object, e As System.EventArgs) Handles StartButton.Click
Start()
End Sub
Private Sub Start_All_Click(sender As System.Object, e As System.EventArgs) Handles Start_All.Click
StartAll()
End Sub