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MicroByte

Dec 21 2005, 01:23 PM

This tutorial shows how to make a timer based calculator with +, - , / and * functions.

Now, File/New Project and make Windows Application.
Then make enough space to create 16 buttons and 2 text fields. And make sure that Button1 is in number 1's place, Button2 is in number 2's place and so on. Numbers 1-9(for some reason, 0 doesnt seem to work [or desimals]). Change the text of the buttons, Button1 to 1, Button2 to 2... but don't change name, or you have to change the code below.
Then insert then buttons anyway you like and the rest of the buttons, you can rename anyway you want. I renamed them in Finnish, laske; jaettuna....
Make 1 textbox, rename it text1, clear the text1 area, then again make textbox2, rename it to text2, clear the text2 area and just write the following code to buttons:

CODE

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Text1.Text = Text1.Text + "1"
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Text1.Text = Text1.Text + "2"
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        Text1.Text = Text1.Text + "3"
    End Sub

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        Text1.Text = Text1.Text + "4"
    End Sub

    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click
        Text1.Text = Text1.Text + "5"
    End Sub

    Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
        Text1.Text = Text1.Text + "6"
    End Sub

    Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click
        Text1.Text = Text1.Text + "7"
    End Sub

    Private Sub Button8_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button8.Click
        Text1.Text = Text1.Text + "8"
    End Sub

    Private Sub Button9_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button9.Click
        Text1.Text = Text1.Text + "9"
    End Sub

    Private Sub zero_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click
        Text1.Text = Text1.Text + "0"
    End Sub

Ok, that makes the numbers see on the textbox. Now you need to have 5 buttons for calculating actions. -, +, / and * buttons, with name you prefer. I call them plus (+), miinus(-), jaettuna(/) and kertaa(*). Then insert 4 timers there on form, anywhere. Check the name is Timer1, Timer2, Timer3, and Timer4. After that, write this code to each of the calculating function buttons:

CODE

    Private Sub miinus_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles miinus.Click
        Text2.Text = Text1.Text
        Text1.Text = ""
        Timer1.Enabled = True
        Timer2.Enabled = False
        Timer3.Enabled = False
        Timer4.Enabled = False
    End Sub
    Private Sub plus_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles plus.Click
        Text2.Text = Text1.Text
        Text1.Text = ""
        Timer1.Enabled = False
        Timer2.Enabled = True
        Timer3.Enabled = False
        Timer4.Enabled = False
    End Sub
    Private Sub kertaa_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles kertaa.Click
        Text2.Text = Text1.Text
        Text1.Text = ""
        Timer1.Enabled = False
        Timer2.Enabled = False
        Timer3.Enabled = True
        Timer4.Enabled = False
    End Sub
    Private Sub jaettuna_click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles jaettuna.Click
        Text2.Text = Text1.Text
        Text1.Text = ""
        Timer1.Enabled = False
        Timer2.Enabled = False
        Timer3.Enabled = False
        Timer4.Enabled = True
    End Sub

That makes the timer recognize the order. Then this code to "="(I call it laske) button:

CODE

    Private Sub laske_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles laske.Click
        If Timer1.Enabled = True Then
            Text1.Text = Val(Text2.Text) - Val(Text1.Text)
        ElseIf Timer2.Enabled = True Then
            Text1.Text = Val(Text2.Text) + Val(Text1.Text)
        ElseIf Timer3.Enabled = True Then
            Text1.Text = Val(Text2.Text) * Val(Text1.Text)
        ElseIf Timer4.Enabled = True Then
            Text1.Text = Val(Text2.Text) / Val(Text1.Text)
        End If
    End Sub

That makes the calculate process. Then add these lines to up:

CODE

Dim lasku As Integer

Now, all we need is the "Clear" button, it's simpler than going to shop:

CODE

Private Sub clear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles clear.Click
        Text1.Text = ""
        Text2.Text = ""
    End Sub

All done!

--------------------------------------------------------
IMPORTANT: Feel free to change text or the name of the buttons anyway you like. Just remember, when you change button name, you must change it in the code section too.
This is very simple counter, i dont expect it to be good or anything, but this is the first thing i made for 6 hours thinking

--------------------------------------------------------

My result: http://iltsu.homelinux.org/~microbit/Laskin.zip

ronson

Jan 8 2006, 07:16 PM

Ok i've found quite a few problems with your tutorial.

1) The naming of the controls, they MUST be renamed. Not only for standards and good practice, but if your making a big program giving them a useful name does good with the prefix of btn, tmr, lbl, txt, lst, cbo etc...

2) The code you have given is very confusing but not just for me but for anyone, there are no comments or explanations of the code so for any new programmers they might find it VERY confusing/intimidating and dismiss the tutorial.

3) You should include screen shots with the tutorial because i personally find just text tutorial borings but screen shots also help the user understand more etc.

4) Your tutorial also doesn't handle decimal numbers

5) The coding is very messy and it could be done easier.

Hope this helps and don't take this negative, it's only advice.

James

P.S. PM me with any questions.

Raremandan

Jan 10 2006, 02:15 PM

I found this.

I'm currently learning by doing tutorials, and too understand that i'd have too copy and paste the code, in which i'm not doing as I hate learning by C+P so i'm writing the code down, only he leaves no explanation too what it all does

- Dan

QUOTE(ronson @ Jan 9 2006, 12:16 AM)

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