make my own UserControl and I can aggregate new TabPages to a TabControl and then, inside of then TabPage, I add my own UserControl using the following code.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim TabX As New Windows.Forms.TabPage("Tab " & TabCount.ToString) '(ConfiguracionTabPage)
Dim MyControl As New ClientesEmpresa
MyControl.Name = "Control" & TabCount.ToString
If ClientesTabControl.TabPages.Count = 10 Then
ClientesTabControl.TabPages.RemoveAt(9)
End If
TabX.Controls.Add(MyControl)
TabX.Name = "Tab" & TabCount.ToString
TabX.Text = "Tab" & TabCount.ToString
MyControl.TitularLbl.Text = "Coca Cola"
Me.ClientesTabControl.TabPages.Insert(0, TabX)
Me.ClientesTabControl.SelectedIndex = 0
TabCount += 1
End Sub
My user control have several Labels, TextBox and TabPages(inside of a TabControl).
Now I want to change some properties dynamically from the source code, but I don't know how to access them.
The most similar theme that I found is this How to Acces of an User control in c#, but, as the title says, is in C#, how I can do it in VB.NET?
Sorry, I just notice that the Enter key post the comment. :(
Thanks for your feedback, I understand what are you saying but I missing something in the middle.
When I create the control in running time in the above code I can access easily to the properties of the created object, in this case my UserControl, but I don't understand how to reach the properties of a particular instance of that control from outside of Button_Click; ie. another button_click event(second button)
I was thinking to use something like
Dim ControlList As Windows.Forms.Control() = Me.ClientesTabControl.TabPages(0).Controls.Find("ModeloLbl", True)
or
ClientesTabControl.TabPages(0).Controls.OfType(Of AlarmasVehiculo)()
But I'm stuck here.
------------------------------------- 3th post ---------------
Thanks Steve, I was resolved using "Control.Find" and a For Each but your solution is easier.
There's any way to get the name of the selected tab or I must to create an Array when I create the New TabPage?, the idea is to update the text of the controls inside of the selected tab only when is selected by the user or every 5 seconds but just the in selected one.
Thanks.
To borrow M4N's answer from the C# question, and translate it to VB:
Cleanest way is to expose the desired properties as properties of your usercontrol, e.g:
Public Class MyUserControl
' expose the Text of the richtext control (read-only)
Public ReadOnly Property TextOfRichTextBox As String
Get
Return richTextBox.Text
End Get
End Property
' expose the Checked Property of a checkbox (read/write)
Public Property CheckBoxProperty As Boolean
Get
Return checkBox.Checked
End Get
Set (value As Boolean)
checkBox.Checked = value
End Set
End Property
'...
End Class
In this way you can control which properties you want to expose and whether they should be read/write or read-only. (of course you should use better names for the properties, depending on their meaning).
Another advantage of this approach is that it hides the internal implementation of your user control. Should you ever want to exchange your richtext control with a different one, you won't break the callers/users of your control.
To answer your second question, if you need to access your dynamically created controls, you can do so easily using their names, for instance:
Dim c As ClientesEmpresa= CType(Me.ClientesTabControl.TabPages("Tab1").Controls("Control1"), ClientesEmpresa)
c.CheckBoxProperty = True
Related
I am learning vb.net and I'm having issues searching for what I need. I want to create a button that is "re-usable" throughout my application without needing to write code for each instance. So, what I would like to start with is take a variable in a form, example, public integer value and when this value changes I want to write to the text of a button. I know I can easily do this by writing code in the form btn_xxx.text = variable, but what if I have several buttons and each button looks at the same variable? Currently what I do is create a component which inherits a button and have a timer that on tick will look at the variable and write to the text. I'm sure there is a better way. Can anyone point me in the right direction? I know part of my problem is I don't know the nomenclature on what things are called, so hopefully I asked my question without too much confusion.
I saw this, https://www.daniweb.com/programming/software-development/threads/124842/detect-variable-change, but I don't see how to adapt that to my situation.
Here is what I have:
Private WithEvents Active_Alarm As New Nav_Active_Alarm
Then inside of a sub that calculates the count:
Active_Alarm.Count = CInt(dt_Active_Alarms.Rows.Count)
The user control:
Public Class Nav_Active_Alarm
Private mActive_Alarm_Count As Integer
Public Event Active_Alarm_Count_Changed(ByVal mvalue As Integer)
Public Property Count() As Integer
Get
Count = mActive_Alarm_Count
End Get
Set(ByVal value As Integer)
mActive_Alarm_Count = value
If Not Me.DesignMode Then
RaiseEvent Active_Alarm_Count_Changed(mActive_Alarm_Count)
test()
End If
End Set
End Property
Private Sub test()
If Not Me.DesignMode Then
If mActive_Alarm_Count = 0 Then
Me.btn_Goto_Active_Alarm.Image = My.Resources.Alarm_Clock_Static
'console or msgbox will work but updating the image will not
Else
Me.btn_Goto_Active_Alarm.Image = My.Resources.Alarm_Clock_Animation
'console or msgbox will work but updating the image will not
End If
End If
End Sub
End Class
If I write to console or add a msgbox I will see the event working. But, the image will not change. If I call the test sub from a timer it will work. Why won't the button update (by the way, I did try refresh and update in the code)?
Observer pattern is what you probably looking for.
This is quick and dirty.
Create a class to hold the variable value. Add a method that adds a button instance to a list.
Then a button that needs to know about the variable calls the register method.
When the value of the variable changes, it iterates through the list of buttons and sets the Text property of each one.
You might have jumped in a bit too deep too quick here. Google Custom data binding in .net, there's loads of built in stuff you can use. Though do it yourself is a good exercise.
A simple method to do this might be:
Create a form level list to hold the buttons you are interested in
Add the buttons you are interested in, into the list (maybe in form load or some other place where you have initialization code)
Create a private property in your form with a backing variable to hold the value you want to have applied to the buttons. In the setter portion spin through the list and set each buttons text.
Dim lstButtons As New List(Of Button)
Sub SetupButtons()
'call from form load or other init code
lstButtons.Add(btnPopulate)
lstButtons.Add(btnPopulate)
End Sub
Private _buttonText As String
Private Property ButtonText As String
Get
Return _buttonText
End Get
Set(value As String)
_buttonText = value
For Each b As Button In lstButtons
b.Text = value
Next
End Set
End Property
When you set the property - which now acts as your variable - it will update all of your textboxes for you.
I realize you mentioned without having to write code - but something has to tie things together. Even if you used the observer pattern (which is an elegant solution for this - so props to those who suggested it) you'd probably end up creating a class to hold the property and have that class implement the INotifyPropertyChanged from System.ComponentModel, and then you'd also have to have each button have a databinding for its text property to the property in the object of your class. There isn't really a way (that I can think of) to get around having to write some code for each form you do this in (though the class part you'd only have to write once of course).
I know, that there are many questions related to this, but still I cannot find a workable solution.
Usually, it would work like this: A form creates an instance of another form in it's container like this:
Dim PolInstIn As New SubForm1
Private Sub LoadDetail()
PolInstIn.TopLevel = False
PolInstIn.Name = "Sub From"
PolInstIn.FormBorderStyle = Windows.Forms.FormBorderStyle.None
PolInstIn.Dock = DockStyle.Fill
Me.GroupBox6.Controls.Add(PolInstIn)
PolInstIn.Show()
End Sub
Then it's easy to call a Public Sub from the sub form like this:
Call PolInstIn.MyPublicSubInSubForm1()
However, this doesn't work for me in this case. When I run MyPublicSubInSubForm1() it doesn't throw any error, but does no action. If I write a value to SubForm1 textbox and read it back, it reads, but I don't see it on the screen, so I suspect it is written to some other accidental instance.
I suspect it is because my parent form is also an instance of an form created in very similar way like SubForm1. Basically the ParentForm is a form loaded into tabPage and SubForm1 is a module loaded into ParentForm. It can exist in many copies (tabs).
Could you point to any simple solutions?
Regards,
Libor
I see this question got a lot of views, so here is an answer.
1) No visual response of child form (only results) - this could have happened if I created more then 1 instances of the form. The example is just an example, but if one use it (accidentally) this way, it may result in new definition of a child form every time (and consequent symptoms like the ones described). In practice, I split form loading from loading data into to the form (done by a public sub in that form).
2) If you want also a back reference (to i.e. parent grid form), define a Public ParentFormGrid as GridName (note ParentForm is a reserved name) and on loading a child form, set
PollInstIn.ParentFormGrid = Me
This way you can alway asccess the parent form, i.e. reload the grid when you save changes on a line edited in child form.
make Private Sub LoadDetail() to a public :
Public Sub LoadDetail()
It work on my project. Hopely its what you want
Dim PolInstIn As New SubForm1
Private Sub LoadDetail()
PolInstIn.Name = "Sub From"
PolInstIn.Show()
PolInstIn.TopLevel = False
PolInstIn.FormBorderStyle = Windows.Forms.FormBorderStyle.None
PolInstIn.Dock = DockStyle.Fill
PolInstIn.Update()
PolInstIn.Refresh()
Me.GroupBox6.Controls.Add(PolInstIn)
End Sub
I'm facing a deadend When trying to call this sub :
Public Sub backblue(ByVal frm As Form, ByVal boxname As String)
For i = 1 To 3
CType(frm.Controls(boxname & i.ToString()), TextBox).BackColor = Color.LightBlue
Next
End Sub
with button click event :
Private Sub Button1_click and bla bla....
backblue(Me, "txb1_")
End Sub
Can anybody show me a suggestion to fix the code.
It throws "Object Referrence not set to an instance bla bla" error
For information the textbox names are :
txb1_1 , txb1_2 , txb1_3
(these are some of the many textboxes in the form that i want its bakcolor changed)
and these three textboxes are already created through designer, not from execution.
i did check the textboxes names and there's nothing wrong.
the form class is also public.
if they are the only textboxs on said form you can just loop through
For Each box as Textbox In frm.Controls
box.BackColor = Color.LightBlue
Next
This error will occur if you do not declare the Form class to be public.
Also, make sure the textbox names are really correct, although this will probably cause a different error.
If you create the textboxes during execution, make sure they are initialized with New and added to the form's Controls collection.
Try this....
Public Sub backblue(ByVal frm As Form, ByVal prefix As String)
For i = 1 To 3
Dim bxName as String = prefix & i.ToString()
Dim bx as TextBox = CType(frm.Controls(bxName), TextBox)
If bx Is Nothing Then
MsgBox("Unable to find text box " +bxName)
Dim mtch() As Control = frm.Controls.Find(bxName, true)
If mtch.Length> 0 then
bx = mtch(0)
Else
Continue For
End if
End If
Bx.BackColor = Color.LightBlue
Next
End Sub
Although, a better solution would be to either create the textboxes inside a control and pass that control to BackBlue or to create an collection that has the controls and pass that in. Which brings up what is most likely yor problem your control is contained in a sub component and thus is not in the main form control collection
Alternative, you could use either the tag of the control or create a component control that implements IExtenderProvider and add it to the form --all of the above would effectively allow you to define the controls and/how they should be handled at designtime.
It may really seem that the names generated by this loop may not be the names of the original textboxes. My suggestion is before setting this Color property verify that the names generated by this loop are indeed the actual names. Maybe output this in a messagebox:
MessageBox.Show(boxname & i.ToString()) for each loop before you set the property
I know that if I want to dynamically create a new instance of an existing form, I can simply do this...
Dim NewForm As New ExistingForm
... and a new instance of all of the controls from ExistingForm will be available in NewForm.
But what if I want to create a new instance of an existing control that's inside a separate existing form?
More specifically, let's say I have 2 forms - FormA and FormB. Inside FormB is an existing panel (we'll call it ExistingPanel). And inside ExistingPanel are several buttons, text boxes, etc., arranged exactly how I want them.
OK, so... inside a button's click event in FormA, I want to do something like this (it doesn't work, obviously, but should give you a good idea as to what I'm trying to accomplish)...
Dim NewExistingPanel As New FormB.ExistingPanel
And then I want NewExistingPanel to contain new instances all of the individual controls from ExistingPanel (so that I can dynamically manipulate each one individually).
So basically, my program will need to create several NewExistingPanels at runtime. And I will need to access each one (and all of its child controls) individually, after they have been created.
How can I accomplish this? I've been experimenting with this for several hours with no luck so far, so figured I'd break down and ask the real professionals :)
When you create a new user control, you could use a dictionary with the tag value as key and the control name as value. Then you can access the control directly by using the IndexOfKey method.
Dim NewForm2 As New Form2
Dim ControlIndex As New Dictionary(Of String, String)
For I = 0 To 2
Dim NewPanel As New WindowsControlLibrary2.MyCustomPanel
NewPanel.Name = "Panel-" + I.ToString
NewPanel.Location = New Point(0 + (NewPanel.Size.Width * I), 0)
NewPanel.Tag = "MyTagValue" + I.ToString
ControlIndex.Add(NewPanel.Tag, NewPanel.Name)
NewForm2.Controls.Add(NewPanel)
NewForm2.Update()
Next
NewForm2.Show()
Dim CurrentPanel As WindowsControlLibrary2.MyCustomPanel =NewForm2.Controls(NewForm2.Controls.IndexOfKey(ControlIndex("MyTagValue1")))
To add control such as panel with textboxes ang button in it ..
In your project - Add > Usercontrol -->
in this part you can make panel with textboxes and button as you want
name it as "myPanel" and save it as "myPanel.vb" --> or whatever you want
In your form and the button named button1 you can add to your button1_click event :
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim mypanel1 As New MyPanel
mypanel1.Location = New Point(0, 0)
Controls.Add(mypanel1)
mypanel1.TextBox1.Text = "Hi, Im new"
End Sub
And you will get your panel at runtime ...
And you will get the textbox1.text fill with "Hi, I'm new" ...
You could create a user control that lays out your sub-controls the way you want them, then create new instances of that. Add New > User Control in the solution menu, then build, and your controls should be ready to drag into the designer at the top of the Toolbox or to instantiate in code like any other control.
To expand on my comment:
Private somePanels As New Dictionary(Of String, YourUserControl)
Then you can just add them as follows:
Dim c As New YourUserControl()
…
Me.Controls.Add(c)
somePanels.Add("SomeTag", c) ' Instead of using Tag; if your tags are numbers, use a List instead of a Dictionary
And access them as:
Dim c = somePanels("SomeTag")
I am trying to implement another form into already complete routine. Basically all the code is there, all I need to do is manipulate the data in a different manner.
I have a routine that looks like this for instance.
This is a paraphrase example:
Private Sub getReportValues(ByRef fr As frmCustomReport, ByRef ReportInfo As ReportValues)
ReportInfo.eHeaderColor = Microsoft.Win32.Registry.CurrentUser.CreateSubKey("Software\FE Jupiter\MSSMonitor").GetValue("Report Equipment Header Color", "DCDCDC") 'Gainsboro
ReportInfo.mHeaderColor = Microsoft.Win32.Registry.CurrentUser.CreateSubKey("Software\FE Jupiter\MSSMonitor").GetValue("Report Monitor Header Color", "FFF8DC") 'Cornsilk
fr.btnEquipColor.PickedColor = System.Drawing.ColorTranslator.FromHtml("#" & Microsoft.VisualBasic.Conversion.Hex("&HFF" & ReportInfo.eHeaderColor))
The problem lays with the (fr as frmCustomReport) I want to make it a system.windows.forms.form but then I would lose the ability to use its objects. I should also mention that fr is a modal dialog and that I don't want a really hacky controlcollection work around for this. Does anyone have a good direction on this?
Note Also!!! The controls I want to access on both forms are almost identical. The only diffrence is layout and some added functionality.
Without a little more information,it is a little hard to give a concrete example. This will work depending on the amount of interaction you need to do. Create a subroutine that accepts the Base Class as an argument, take a look at the Name value and base your conditional logic off of that using CType to cast the Form to the proper type.
Private Sub clickOtherFormsButton(Value As Form)
If Value.Name = "Form3" Then
Dim formObject As Form3 = CType(Value, Form3)
formObject.Button1.PerformClick()
ElseIf Value.Name = "Form2" Then
Dim formObject As Form2 = CType(Value, Form2)
formObject.Button1.PerformClick()
End If
End Sub