gambas-source-code/app/examples/Drawing/Chart/.src/FormChart.class

' Gambas class file

' ======================================
' This example is to make a bar chart
' using DrawingArea
' may be it can help you to make a chart
' if you have any question you can send to
'   yudi@kecoak.or.id
' Thank You


Public total As Integer
Public value As Float[]

Public Sub btnClose_Click()

  Me.Close

End

Public Sub _new()
  
  Me.Center
  
End


Public Sub Form_Open()

  Draw_Chart

End

Public Sub Draw_Chart()

  Dim i As Integer

  Dim skala_1 As Integer
  Dim skala_2 As Integer

  Dim distance_x As Float
  Dim distance_y As Float

  Dim width_draw As Integer
  Dim tot As Integer
  Dim colors As Integer[]
  Dim bottom As Integer
  Dim sumdata As Integer

  colors = New Integer[]
  colors.Resize(total + 1)

  For i = 1 To total
    sumdata = sumdata + value[i]
  Next

  If sumdata = 0 Then sumdata = 1

  For i = 1 To total
    value[i] = (value[i] / sumdata) * 10
  Next

  drwchart.Clear

  draw.Begin(drwchart)

  skala_1 = drwchart.ClientH / 11
  distance_y = drwchart.ClientH - skala_1
  bottom = distance_y + 8

  For i = 0 To 100 Step 10
    draw.Foreground = color.black
    draw.Text(i, 0, distance_y)
    draw.Line(25, distance_y + 8, drwchart.clientw, distance_y + 8)
    distance_y = distance_y - skala_1
  Next

  draw.Line(30, 0, 30, drwchart.ClientH)

  skala_2 = (drwchart.ClientW - 30) \ 10
  distance_x = skala_2 + 30
  width_draw = skala_2 / 2

  For i = 1 To Total
       draw.LineWidth = 1
       draw.Foreground = color.Black
       draw.Text(i, distance_x - (width_draw / 2) - 16, drwchart.ClientH - drwChart.Font.Height, 32, drwChart.Font.Height, Align.Center)
       draw.Line(distance_x - (width_draw / 2), 0, distance_x - (width_draw / 2), drwchart.ClientH - skala_1 + 8)
       draw.LineWidth = width_draw
       draw.Foreground = color.RGB(i * 100, i * 10, i * 50)
       colors[i] = draw.Foreground
       tot = skala_1 * value[i] + skala_1 - 8
       draw.Line(distance_x - (width_draw / 2), bottom, distance_x - (width_draw / 2), drwchart.ClientH - tot)
       distance_x = distance_x + skala_2
  Next

  Draw.End

End

Public Sub btnAbout_Click()

  Dim i As String
  i = ("<h2>Example to make bar chart</h2>\n")
  i = i & ("This example has made by : ") & Chr(10)
  i = i & "   Yudi Astira" & Chr(10)
  i = i & "   yudi@kecoak.or.id" & Chr(10)
  i = i & "   necrose #hdteam on Dal.Net" & Chr(10)
  i = i & ("Thank You")
  message.Info(i, ("&Close"))
  
End