Use code on multiple forms without copying it? inheritance?

Hey there, I'm working on a game set in a simulated computer environment. I've made a template forum which I use to copy and paste the code from to every single form. Here's a small bit of the code I use within the game that is copied to all the windows:

Code:

---

Public Sub setuptitlebar()

        titlebar.Height = ShiftOSDesktop.titlebarheight
        Me.Size = New Size(366, 167) 'put the default size of your window here
        Me.Size = New Size(Me.Width, Me.Height + ShiftOSDesktop.titlebarheight - 30)

        pgleft.Width = ShiftOSDesktop.windowbordersize
        pgright.Width = ShiftOSDesktop.windowbordersize
        pgbottom.Height = ShiftOSDesktop.windowbordersize
        Me.Size = New Size(Me.Width + ShiftOSDesktop.windowbordersize + ShiftOSDesktop.windowbordersize, Me.Height + ShiftOSDesktop.windowbordersize)

        If ShiftOSDesktop.showwindowcorners = True Then
            pgtoplcorner.Show()
            pgtoprcorner.Show()
        Else
            pgtoplcorner.Hide()
            pgtoprcorner.Hide()
        End If

        If ShiftOSDesktop.boughttitlebar = False Then
            titlebar.Hide()
            Me.Size = New Size(Me.Width, Me.Size.Height - titlebar.Height)
        End If

        If ShiftOSDesktop.boughttitletext = False Then
            lbtitletext.Hide()
        Else
            lbtitletext.Font = New Font(ShiftOSDesktop.titletextfont, ShiftOSDesktop.titletextsize, ShiftOSDesktop.titletextstyle)
            lbtitletext.Show()
        End If

        If ShiftOSDesktop.boughtclosebutton = False Then
            closebutton.Hide()
        Else
            closebutton.BackColor = ShiftOSDesktop.closebuttoncolour
            closebutton.Height = ShiftOSDesktop.closebuttonheight
            closebutton.Width = ShiftOSDesktop.closebuttonwidth
            closebutton.Show()
        End If

        If ShiftOSDesktop.boughtrollupbutton = False Then
            rollupbutton.Hide()
        Else
            rollupbutton.BackColor = ShiftOSDesktop.rollupbuttoncolour
            rollupbutton.Height = ShiftOSDesktop.rollupbuttonheight
            rollupbutton.Width = ShiftOSDesktop.rollupbuttonwidth
            rollupbutton.Show()
        End If

        If ShiftOSDesktop.boughtwindowborders = True Then
            closebutton.Location = New Point(titlebar.Size.Width - ShiftOSDesktop.closebuttonside - closebutton.Size.Width, ShiftOSDesktop.closebuttontop)
            rollupbutton.Location = New Point(titlebar.Size.Width - ShiftOSDesktop.rollupbuttonside - rollupbutton.Size.Width, ShiftOSDesktop.rollupbuttontop)
            Select Case ShiftOSDesktop.titletextposition
                Case "Left"
                    lbtitletext.Location = New Point(ShiftOSDesktop.titletextside, ShiftOSDesktop.titletexttop)
                Case "Centre"
                    lbtitletext.Location = New Point((titlebar.Width / 2) - lbtitletext.Width / 2, ShiftOSDesktop.titletexttop)
            End Select
            lbtitletext.ForeColor = ShiftOSDesktop.titletextcolour
        Else
            closebutton.Location = New Point(titlebar.Size.Width - ShiftOSDesktop.closebuttonside - pgtoplcorner.Width - pgtoprcorner.Width - closebutton.Size.Width, ShiftOSDesktop.closebuttontop)
            rollupbutton.Location = New Point(titlebar.Size.Width - ShiftOSDesktop.rollupbuttonside - pgtoplcorner.Width - pgtoprcorner.Width - rollupbutton.Size.Width, ShiftOSDesktop.rollupbuttontop)
            Select Case ShiftOSDesktop.titletextposition
                Case "Left"
                    lbtitletext.Location = New Point(ShiftOSDesktop.titletextside + pgtoplcorner.Width, ShiftOSDesktop.titletexttop)
                Case "Centre"
                    lbtitletext.Location = New Point((titlebar.Width / 2) - lbtitletext.Width / 2, ShiftOSDesktop.titletexttop)
            End Select
            lbtitletext.ForeColor = ShiftOSDesktop.titletextcolour
        End If

        If ShiftOSDesktop.boughtclockicon = True Then
            pnlicon.Visible = True
            pnlicon.Location = New Point(ShiftOSDesktop.titlebariconside, ShiftOSDesktop.titlebaricontop)
        End If

    End Sub

---

Is there a way I can simply say "Inherit setuptitlebar" in each window or something so I don't have to copy over all the code to each window? I often update the code and copying it across to 20 windows again and again (soon to be more) drives me mad.

So what's the simplest way to do this knowing that the controls on each window have the exact same names?

P.S The graphical environment is highly customizable so don't freak out or tell me that I'm over-complicating the code... trust me, I'm not!

Put the code in a module (class?) and call it from each form, something like:

(Module code)

Code:

---

Module Module1
    Public Sub formatForm(ByVal whichForm As Form)
        whichForm.BackColor = Color.Blue
        whichForm.Height = 100
        whichForm.Width = 200
        whichForm.StartPosition = FormStartPosition.Manual
        whichForm.Left = 0
        whichForm.Top = 0
    End Sub
End Module

---

(Form code)

Code:

---

Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        Call Module1.formatForm(Me)
    End Sub

---

You mentioned inheritance in your thread title. Why not use it? You simply design a form, put that method into it, along with any others that you want to share, and then have all your other forms inherit from it.

FD, I don't have any experience along those lines. If he does it that way, when he changes the one that he inherits from, do the others get "updated automatically?"

Bryce

Yes, that's the point of inheritance. All the derived forms share the behaviour of the forms they inherit from. If the behaviour of the inherited form changes then so does the behaviour of all the derived forms.

It does introduce a bit of a potential problem though: what to do if you want to update the template for but have one or two forms whose behaviour does not change. In that case the individual forms whose behavious you want to differ need to 'override' or 'hide' the method(s) of the forms from which they inherit. Overriding is generally recommended. That means they can have their own specific implementation that supercedes the shared behaviour. All told inheritance is a very powerful technique for achieving code re-use.

It's proabbly a little advanced if you're coming to this stuff green but you might also want to read up on the strategy pattern. Inheritance and overriding will only take you so far and starts to become inneficient when you have several different behaviours, each of which is shared by some but not all of your forms. Inheritance only allows for a single shared behaviour so this is difficult to implement using inheritance without creating a horribly complex structure. What you do instead is compose different behaviours, similar to calling a method from a module as you suggested. There's a few key differences that make it more robust though and it's important to understand them so it's worth coming to this via inheritance.

Thanks for explaining!

So lets say that code I shared in the first post is within a form called "template". I then want to use that in a form called "textpad" and "clock" and "Shifter" and 10 other forms... how do I do that? What do I type and where do I type it to get that code in the template to be used across all the forms?

I work best when I see an example. I then modify and experiment with the example to learn.

Thanks in advance for help :) Also note that I've never used inheritance before but my current project "ShiftOS" is screaming for me to use it.

Right-click the project. Select Add -> New Item.
In the Add New Item dialog that comes up, select Windows Forms on the left. On the right, find "Inherited Form".
Click Add.
WAIT...
Eventually another dialog will come up asking for which form to inherit from... select your template form...
Click OK.
done... you've just added an inherited form to your project.

-tg