Write a program that allows the user to display a budget as a pie chart. After the user enters numbers into the four text boxes a presses the button, the pie chart should be displayed.
When I push the button for my code it does not display anything. Could you help me determine what I am not doing and give me an idea how to include into my code thanks.
Code below:
Private Sub btnDisplay_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplay.Click
Dim Housing, Transportation, Food, Other As String
Dim legend() As String = {"Housing", "Transportation", "Food", "Other"}
Dim quantity() As Single = {}
Dim percent(quantity.GetUpperBound(0)) As Single
Dim sumOfQuantities As Single = 0
Dim sumOfSweepAngles As Single = 0
Dim br() As Brush = {Brushes.Blue, Brushes.Red, Brushes.Tan, _
Brushes.Green, Brushes.Orange, Brushes.Gray}
Dim gr As Graphics = picBudget.CreateGraphics
Housing = CStr(txtHousing.Text)
Transportation = CStr(txtTransportation.Text)
Food = CStr(txtFood.Text)
Other = CStr(txtOther.Text)
'The picture box has widith 312 and height 215
Dim r As Integer = 100 'Radius of circle
Dim c As Integer = 105 'Center of circle has coordinates (c,c)
Me.Text = "Budget"
'Convert the quantities to percents
For i As Integer = 0 To quantity.GetUpperBound(0)
percent(i) = quantity(i) / sumOfQuantities
gr.FillPie(br(i), c - r, c - r, 2 * r, 2 * r, sumOfSweepAngles, percent(i) * 360)
sumOfSweepAngles += percent(i) * 360
gr.FillRectangle(br(i), 220, 20 + 30 * i, 20, 20)
gr.DrawString(legend(i), Me.Font, Brushes.Black, 250, 22 + 30 * i)
Next
End Sub
The program actually makes a pie-chart, after making a few adjustments.
1. You will need to declare the dimension of quantity. As it is, I believe it defaults to 1.
You could put in a bunch zeroes to occupy the four spaces, such as:
Dim quantity() As Single = {0, 0, 0, 0}
2. The sum of quantities variable must be calculated using a for-loop prior to drawing the pie-chart which requires "sumOfQuantities" to calculate the percentage. Do not forget to initialize sumOfQuantities to zero before entering the for-loop.
3. You'll need to manually transfer the values of Housing.text into quantity(0), etc. For example:
quantity(0)=CSng(txtHousing.text)
...
After that, the program should work. By changing the values in the textbox, and pressing the button, the graphics will update itself.
Good work!
Thank you so very much. I got the program to run.
Based on the provided code, it seems that the issue might be related to not assigning any values to the "quantity" array. This array is used to store the numerical values entered by the user.
To fix the issue, you should update your code to assign the values entered in the text boxes to the "quantity" array. Here's an example:
```vb
Private Sub btnDisplay_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplay.Click
Dim Housing, Transportation, Food, Other As Single ' Use Single data type for numerical values
Dim legend() As String = {"Housing", "Transportation", "Food", "Other"}
Dim quantity() As Single = {}
Dim percent(quantity.GetUpperBound(0)) As Single
Dim sumOfQuantities As Single = 0
Dim sumOfSweepAngles As Single = 0
Dim br() As Brush = {Brushes.Blue, Brushes.Red, Brushes.Tan, _
Brushes.Green, Brushes.Orange, Brushes.Gray}
Dim gr As Graphics = picBudget.CreateGraphics
Housing = CSng(txtHousing.Text) ' Convert text to Single
Transportation = CSng(txtTransportation.Text) ' Convert text to Single
Food = CSng(txtFood.Text) ' Convert text to Single
Other = CSng(txtOther.Text) ' Convert text to Single
' Add the quantities to the "quantity" array
quantity = {Housing, Transportation, Food, Other}
' Calculate the sum of quantities
sumOfQuantities = quantity.Sum()
'The picture box has widith 312 and height 215
Dim r As Integer = 100 'Radius of circle
Dim c As Integer = 105 'Center of circle has coordinates (c,c)
Me.Text = "Budget"
'Convert the quantities to percents
For i As Integer = 0 To quantity.GetUpperBound(0)
percent(i) = quantity(i) / sumOfQuantities
gr.FillPie(br(i), c - r, c - r, 2 * r, 2 * r, sumOfSweepAngles, percent(i) * 360)
sumOfSweepAngles += percent(i) * 360
gr.FillRectangle(br(i), 220, 20 + 30 * i, 20, 20)
gr.DrawString(legend(i), Me.Font, Brushes.Black, 250, 22 + 30 * i)
Next
End Sub
```
In this updated code, the values entered in the text boxes are converted to the Single data type using the CSng function. Then, these values are added to the "quantity" array. Finally, the code proceeds with calculating the pie chart based on the updated "quantity" array.
Make sure to run this updated code and check if you can now see the pie chart after clicking the button.