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Accessing public events within nested UserControls?
Ok,
I hope I can convey what I'm trying to do....
I have a single UserControl (uc1) that is comprised of 6 other UserControls (ucSub1, ucSub2...).
UserControls ucSub1 - ucSub6 contain various controls, among them...a ComboBox. Each combobox needs to be populated via a DataTable utilizing the "DisplayMember" and "ValueMember" properties.
uc1 is created dynamically and can have up to 12 instances. Each instance is placed on a dynamically created TabPage of a TabControl.
12 uc's = 12 tabpages.
Each ucSub? has within it's code-behind the following statement: Public Event LoadCombos()
At this point, uc1 has no code-behind code.
I'm pretty sure at some point I need to add an event using the "AddHandler" that will fire when a uc? control is created.
Here is my question:
What is the best way to code this so that when a uc? control is added, all the ComboBoxes of each ucSub? is populated?
I hope I can convey what I'm trying to do....
I have a single UserControl (uc1) that is comprised of 6 other UserControls (ucSub1, ucSub2...).
UserControls ucSub1 - ucSub6 contain various controls, among them...a ComboBox. Each combobox needs to be populated via a DataTable utilizing the "DisplayMember" and "ValueMember" properties.
uc1 is created dynamically and can have up to 12 instances. Each instance is placed on a dynamically created TabPage of a TabControl.
12 uc's = 12 tabpages.
Each ucSub? has within it's code-behind the following statement: Public Event LoadCombos()
At this point, uc1 has no code-behind code.
I'm pretty sure at some point I need to add an event using the "AddHandler" that will fire when a uc? control is created.
Here is my question:
What is the best way to code this so that when a uc? control is added, all the ComboBoxes of each ucSub? is populated?
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Are the six "sub" UserControls created dynamically for each "parent" UserControl?...or are they placed statically at design-time thru the designer?
Then I think you're going about it backwards. Instead of the subUCs raising an event that the mainUC subscribes to, why not just have the mainUC call a Public method in the subUCs telling them to load? This way the mainUC could also pass any necessary information to the subUCs that they need to load the correct data...
Do you have an example of such a thing.
I only ask because I'm assuming that I would do something like this in the main UC:
Public Event LoadCombos()
But when I go to dynamically create the main UC, how do I reference the "LoadCombos()"?
I only ask because I'm assuming that I would do something like this in the main UC:
Public Event LoadCombos()
But when I go to dynamically create the main UC, how do I reference the "LoadCombos()"?
I'm thinking NO events at all.
Maybe something more like:
Of course, that could be changed up to pass more information from the main usercontrol into the child usercontrol method.
Maybe something more like:
Public Class MainUserControl
Public Sub New()
' This call is required by the designer.
InitializeComponent()
' Add any initialization after the InitializeComponent() call.
SubUserControl1.LoadCombo()
SubUserControl2.LoadCombo()
SubUserControl3.LoadCombo()
SubUserControl4.LoadCombo()
SubUserControl5.LoadCombo()
SubUserControl6.LoadCombo()
End Sub
End Class
Public Class SubUserControl
Public Sub LoadCombo()
' ... load the ComboBox ...
End Sub
End Class
Of course, that could be changed up to pass more information from the main usercontrol into the child usercontrol method.
Inside the SubUserControl so it can access and load the ComboBox.
You may need to change up the MainUserControl so you can load the combos some time after the constructor:
So then you could do:
You may need to change up the MainUserControl so you can load the combos some time after the constructor:
Public Class MainUserControl
Public Sub LoadCombos()
SubUserControl1.LoadCombo()
SubUserControl2.LoadCombo()
SubUserControl3.LoadCombo()
SubUserControl4.LoadCombo()
SubUserControl5.LoadCombo()
SubUserControl6.LoadCombo()
End Sub
End Class
So then you could do:
Dim mainUC As New MainUserControl
' ... do some other stuff with "mainUC" ...
mainUC.LoadCombos()
Mike,
One more thing. In the creation of my main UC, usually an custom event is created using the AddHandler. When doing so, is it required to declare a WithEvents object? For example...using my code below:
One more thing. In the creation of my main UC, usually an custom event is created using the AddHandler. When doing so, is it required to declare a WithEvents object? For example...using my code below:
Public Class Form1
Private WithEvents uc1_??? The question mark being whatever
For Each itm In arrChannels
Dim tab As New TabPage
Dim uC1 As New userChannelSettings
uC1.Name = "ucChannel" & x + 1
uC1.mlChannelName.Text = itm
tab.Controls.Add(uC1)
uC1.ForeColor = tab.ForeColor
AddHandler uc1_???? What kind of event should I add here
tab.Tag = itm
tab.Text = "Channel: " & itm.ToString
tab.Name = "tChannel" & x + 1
tabChannelList.Controls.Add(tab)
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