Adding buttons at runtime - vb.net

I want to place a few buttons on my form. The number is unknown at design time. Actually each button will represent an item entered in combo box. So if user adds an item, a button on the form should be added by the code.
Please advise how to do it?
Thanks
Furqan

You can do this by simply looping over any number (in this case from a combo box) and creating the required number of buttons before adding them to the form.
For i As Integer = 0 To myComboBox.Items.Count - 1
Dim newButton = new Button()
// Add some properties, etc. to the button
newButton.Text = myComboBox.Items(i).ToString()
MyForm.Controls.Add(newButton)
Next

You can use a function like this:
Sub AddButton(ByVal label As String, ByVal location As Point)
Dim b As Button
b = New Button
b.Location = location
b.Text = label
Me.Controls.Add(b)
End Sub

Related

Giving buttons different names through code and referring to them later on

My code creates a 5x5 grid of buttons. I am wanting to give each of these buttons different names "BtnColour1", "BtnColour2", etc. How do I give them all different names and how do I refer to each button later in the program?
Dim bytCounter As Byte
For bytCounter = 1 To 25
Dim btnColour As New Button
Me.Controls.Add(btnColour)
btnColour.Height = 50
btnColour.Width = 50
btnColour.Name = "btnColour" & bytCounter
btnColour.Enabled = False
btnColour.Left = ((bytCounter - 1) Mod 5) * 51
btnColour.Top = ((bytCounter - 1) \ 5) * 51
AddHandler btnColour.Click, AddressOf BtnClick
Your code (I guess you forgot the ending Next) does create 25 Buttons, with names btnColour1... btnColour25.
In the BtnClick event, to get the name of the clicked button, you should write something like:
Private Sub BtnClick(sender As Object, e As EventArgs)
Dim buttonName as string=CType(sender, Button).Name
'buttonName now has the clicked button name
End Sub
Of course, since you set the enabled property to False, your button click event will not fire.
In a general sense (and in addition to Spyros' answer, which is a good way to do it in an event handler - the sender is always the thing that raised the event), when you give a control a name and add it to a control's Controls collection, you can then retrieve it by that name later:
'Here you added the button to the form controls:
Me.Controls.Add(btnColour)
'later in the code you can ask for it back by name, for example:
Dim controls = Me.Controls.Find("btnColour1")
What you get back is an array of Controls. You get an array because Find can search all children (panels inside panels inside groupboxes inside forms etc) and it is thus conceivable that multiple controls in different panels will both have the same name. In your case if you know you only have one control called "btnColour1" it's safe to get it by array index:
Dim control = controls(0) 'controls variable is from the above Find
Lastly, remember that it comes back as a Control, the parent class for all controls. Because you know it's a button, it's safe to cast without check:
Dim button = DirectCast(control, Button)
Remember that if your property is available on the base Control class you don't even need a cast:
'here's a 1 line way to get the text of the button named btnColour1
'Find all controls named btnColour1, take the first, get the text
Dim t = Me.Controls.Find("btnColour1")(0).Text
If you want to refer to the buttons later in the program to change a setting without clicking the button, you can add each button to an array and call each of them with an index number:
Dim buttons(24) As Button
Then as the buttons are created, you can add each button to the array:
Dim bytCounter As Byte
For bytCounter = 1 To 25
Dim btnColour As New Button
Me.Controls.Add(btnColour)
buttons(bytCounter) = btnColour
you can then reference each button and their properties using the index number of the button in the array. You may also want to add a specific tag to each button to make each button more unique using:
btnColour.Tag = bytCounter

Reversi VB.net logic behind it

I am trying to make the reversi game in VB.Net. I have some difficulties translating the game`s logic into vb.net
If a button is black and the button next to it is white,than the button next to the white one will be black wen pressed.
newButton.tag = colum of button + (row of button * amount of columns)
-> I made 64 buttons via a function loop and added a tag
Dim knop As Button = sender
Dim value As String = knop.Tag
If value = "...(?)" Then
knop.BackColor = Color.Black
If ....(?)
End If
End If
I already made a scheme with the label of the buttons, but I find it hard to implement the logic. Can someone help me out with thid one?
EDIT: http://i.stack.imgur.com/3gdrJ.png
If you use Dim ButtonList As List(Of List(Of Button)) and add the buttons to the form in runtime you can add each the button for each row to a list then add that list to ButtonList. Now you can access each button by the indexes in the 2 dimensional list.
Since you're changing the backcolor just use that instead of using the tag.

Order of controls being added to panel, control not showing unless docked

I imagine this is probably an easy to answer question but for some reason I can't get it to work
Sub New(ByVal Sess As AudioSessionControl2)
S_Session = Sess
'Create the panel and position it.
S_Panel.BackColor = Color.AliceBlue
S_Panel.Width = 200
S_Panel.Height = 40
Dim Position As New Point(6, 19)
If G_AppSessions.Count > 0 Then
Position = Point.Add(G_AppSessions.Item(G_AppSessions.Count - 1).SessionPanel.Location, New Point(0, 45))
End If
S_Panel.Location = Position
'Create a label which has the name of the process
Dim S_PName As New Label
S_PName.Text = "Test"
S_PName.Dock = DockStyle.Left
S_Panel.Controls.Add(S_PName)
'Create a button to change volume
Dim S_Save As New Button()
S_Save.Text = "Save"
AddHandler S_Save.Click, AddressOf Save_Click
S_Save.Parent = S_Panel
S_Panel.Controls.Add(S_Save)
S_Volume.Parent = S_Panel
S_PName.Parent = S_Panel
MainForm.Controls.Add(S_Panel)
S_Panel.Parent = MainForm.gb_Applications
End Sub
The problem is that, the label will show because its docked, but the button won't. It will only show if its docked as well, and thats just not what I want. This is part of a class for creating a dynamic UI, where I can create a number of this class to create a bunch of panels for various things.
I don't see anywhere where you are setting the label or button position. You probably have them both at 0,0 and the label is on top of the button, obscuring it. Did you try setting the position of both the controls, making sure they don't overlap?

Opening new form after right click on selected record in continuous form

In my access database before I was using a list box in the form for having list of items and I had below code for opening new form after right click on each selected item in list box.
Private Sub ItemList_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
Const RIGHTBUTTON = 2
If Button = RIGHTBUTTON Then
DoCmd.OpenForm "frmShortcut_GenerateTask"
DoCmd.MoveSize udtPos.X * mp.TwipsPerPixelX, udtPos.Y * mp.TwipsPerPixelY
End If
End Sub
Now I am using a continuous form instead of list box and I have defined a [isselected) field for selecting each record in continuous form after clicking on that. Now my problem is how I have to write code for right clicking and opening new form.
I used the same code I had used for list box, but it does not work and nothing happened.
Private Sub Form_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
Const RIGHTBUTTON = 2
If Button = RIGHTBUTTON Then
DoCmd.OpenForm "frmShortcut_GenerateTask"
DoCmd.MoveSize udtPos.X * mp.TwipsPerPixelX, udtPos.Y * mp.TwipsPerPixelY
End If
End Sub
Private Sub P_Click()
On Error Resume Next
Me.IsSelected = Not Me.IsSelected
' Save the status
Me.Dirty = False
' Force conditional highlighting
P_ForceHighLight
' Update display in SF_Selected
Me.Parent("SF_Selected").Requery
ActiveControl.SelLength = 0
On Error GoTo 0
End Sub
I recommend either using a DoubleClick event in all of your textboxes and combos, or else putting a small button at one edge of your continuous form that allows the user to open records. Right-click is going to give you problems (so will labels and image controls) because this event doesn't cause (or ensure) that the Form's internal Recordset Bookmark property is actually moved to the record they right-clicked on. In my experience, only buttons, textboxes, and comboboxes will move the Bookmark to the record the user is trying to select.
To Test this, try putting code at the top of your different routines that shows you what record is selected:
MsgBox "RecordID = " & Me!RecordIDField
If you are consistently getting the correct ID, then your problem has to do with how your opening your new form, passing parameters or arguments, etc.

Add tooltip control dynamically

I have a child form that is completely created in code.
I would like to add tool tips to the textbox controls on the form. I know how to set up the tool tips on the fly but can't find a way to add the tooltip control to the form on the fly. All the hits I find on google refer to dragging the control from the designers toolbox.
I would need to do something like:
' Add tool tip control
Dim toolTip1 As New ToolTip()
toolTip1.ShowAlways = True
frm.Controls.Add(toolTip1)
This does not work
I tried adding a sub to handle the from.load event(with a handler that poitn to the sub) at design time but can not get passed the error "Tooltip1 is not declared" when adding the tooltip to the iundividual dynamic controls.
If I call this dynamic form from a parent form and add the tooltip control to the parent form I can use it for the child form. But how would I do this if I was creating the form from a routine that does not live on a parent form?
thanks
Dim frm As New Form
' Add tool tip control
''Dim toolTip1 As New ToolTip()
''toolTip1.ShowAlways = True
'Draw the Form object
'close the dynamic frm if existing already
If frm IsNot Nothing Then
frm.Close()
End If
frm = New Form()
frm.AutoScaleDimensions = New System.Drawing.SizeF(6.0F, 13.0F)
frm.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font
frm.Name = "frm_test"
'dimension is irrelevant at the moment
frm.ClientSize = New System.Drawing.Size(10, 10)
'the parent will be the current form
'frm.MdiParent = this;
'splash screen mode form, why not...
frm.ControlBox = True
frm.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
frm.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink
frm.BackColor = System.Drawing.Color.LightGray
For Each item As MYFILE.Class in the Collection
Dim aTextBox As New TextBox()
aTextBox.Font = New System.Drawing.Font(sFont, Single.Parse(sSizeFont), System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CByte(0))
aTextBox.BackColor = System.Drawing.Color.Yellow
aTextBox.Location = New System.Drawing.Point(iNewColumnPosition + 5 + intMaxWidthLabel, intVertPos)
aTextBox.Size = New System.Drawing.Size(intWidthTextBox + 10, intGapHeight)
'store the biggest width, so that the textboxes can be vertically aligned
If intWidthTextBox > intMaxWidthText Then
intMaxWidthText = intWidthTextBox
End If
'giving a name to all your object will be the only way
'to retrieve them and use them
'for the purpose of this sample, the name can be the
'same for all textboxes.
aTextBox.Name = item.ParameterName
'giving the maximun size in caracters for the textbox.
aTextBox.MaxLength = Integer.Parse(item.ParameterLength)
toolTip1.SetToolTip(aTextBox, "TIP" & intIndex.ToString)
'tab have to be ordered
aTextBox.TabIndex = intIndex
intIndex += 1
'Vertical position is to be manage according the
'tallest object in the form, in this case the
'textbox it self
intVertPos += intGapHeight
'adding the textbox to the form
frm.SuspendLayout()
aTextBox.SuspendLayout()
frm.Controls.Add(aTextBox)
Next
I left a lot of code out but this should give you an idea as to what I am doing
In vb it is
Dim tooltip As New ToolTip(components)
tooltip.SetToolTip(textBox1, "This is a textbox tooltip")
Sorry this is not in VB.NET but I am pretty sure you can easily convert this. The first line is to set ToolTip control to your form components. The second is how you set a tooltip to a control and give it the related text.
ToolTip tooltip = new ToolTip(components);
tooltip.SetToolTip(textBox1, "This is a textbox tooltip");