Hello Group I have another problem. I would like to draw tower charts, but I have no idea how to do it … I was able to draw rectangles with a canvas … but for me it is very complicated. I have tried to read the documentation, but it is difficult for me. In Vb6 I chose the graph, I set the values and it was done … from what I understand with Xojo it is different, do I have to set everything myself? I would like to make a tower chart of some values that I have stored in variables for example A = 100 B = 1300 C = 200 D = 400. I’m also worried about the scale factor. Can anyone refer me?
you could wait for mbs offer Monkeybread Software - The MBS Xojo ChartDirector Plugin
my example of a bar chart.
subclassed canvas
Private Property ValueMax As Double = 0
Private Const kToRadian as Number = 0.0174532925199444
Sub Paint(g As Graphics, areas() As Rect) Handles Paint
#If TargetWindows
#pragma unused areas
#EndIf
System.DebugLog("BarChartCanvas Paint")
g.AntiAliased = True
g.AntiAliasMode = Global.Graphics.AntiAliasModes.HighQuality
Paint(g)
System.DebugLog("BarChartCanvas Paint Ready.")
End Sub
Private Sub Calculate()
System.DebugLog("Calculate")
'Get Max Value for Scale Y
Self.ValueMax = 0.0
For i As Integer = 0 To data.LastRowIndex
Self.ValueMax = Max(Self.ValueMax, data(i).Value)
Next
System.DebugLog("ValueMax="+Str(Self.ValueMax))
For i As Integer = 0 To data.LastRowIndex
data(i).ForeColor = PiChart.RandomColor
Next
Data.Sort(AddressOf ComparePiChart) 'sort small to big
End Sub
Public Function ComparePiChart(a as PiChart, b as PiChart) As Integer
if a.Value > b.Value then return 1
if a.Value < b.Value then return -1
return 0
End Function
Public Sub Draw()
Calculate
'Self.Invalidate(True) 'paint event will come then ..
Self.Refresh
End Sub
Public Sub DrawRect(g As Graphics, x1 As Double, x2 As Double, y As Double, foreColor As Color)
System.DebugLog("g.Height="+Str(g.Height))
System.DebugLog("y="+Str(y))
Dim r As New RectShape
r.BorderOpacity = 75 // 100 = opaque border
r.BorderWidth = 1.5
r.BorderColor = Color.White
r.FillOpacity = 90
r.FillColor = foreColor
r.Width = x2 - x1
r.Height = y
r.x = x1
r.y = g.Height -y
g.DrawObject(r,r.Width / 2.0,r.Height/2.0)
End Sub
Public Sub DrawText(g as Graphics, x1 as Double, x2 as Double, y as Double, Name as String)
y=0 'unused
Dim s As New TextShape
s.x = (x1+x2)/2.0
s.y = g.Height / 2.0
s.Value = Name
's.FontUnit = FontUnits.Pixel
s.FontName = "Tahoma"
s.FontSize = Abs(x2-x1) * 0.8
s.Bold = False
s.HorizontalAlignment = TextShape.Alignment.Center
s.VerticalAlignment = TextShape.Alignment.Center
s.Rotation = -90.0 * kToRadian
s.BorderOpacity = 100
s.BorderWidth = 1
s.BorderColor = Color.White
s.FillOpacity = 100
s.FillColor = Color.Black 'Text Farbe
g.DrawObject(s)
End Sub
Public Sub Paint(g As Graphics)
PaintGrid(g)
Dim x As Double = 0.0
Dim y As Double
Dim m As Double = ValueMax
Dim st As Double = g.Width / Data.LastRowIndex
For i As Integer = Data.LastRowIndex DownTo 0
g.DrawingColor = Data(i).ForeColor
y = (Data(i).Value / m) * g.Height
DrawRect(g, x, x + st, y , Data(i).ForeColor)
x = x + st
Next
'overlay text
x = 0.0
For i As Integer = Data.LastRowIndex DownTo 0
DrawText(g, x, x + st, (Data(i).Value / m) * g.Height ,Data(i).Name)
x = x + st
Next
End Sub
Public Sub PaintGrid(g As Graphics)
Dim x As Double = 0.0
Dim st As Double = g.Width / Data.LastRowIndex
For i As Integer = Data.LastRowIndex DownTo 0
Dim l As New FigureShape
l.FillOpacity = 10
l.FillColor = Color.Gray
l.BorderColor = Color.White
l.BorderOpacity = 80
l.BorderWidth = 1.5
l.AddLine(x,0,x+st,0)
l.AddLine(x+st,0,x+st,g.Height)
l.AddLine(x+st,g.Height,x,g.Height)
l.AddLine(x,g.Height,x,0)
g.DrawObject(l)
x = x + st
Next
st = (50.0 / (ValueMax / 12.0) ) * g.Height
g.DrawingColor = Color.Gray
For y As Double = g.Height DownTo 0 Step st
g.DrawLine 0,y,g.Width,y
Next
End Sub
Public Sub ReColor()
For i As Integer = 0 To Data.LastRowIndex
Data(i).ForeColor = PiChart.RandomColor
Next
'Self.Invalidate(True)
Self.Refresh
End Sub
Public Property Data() As PiChart
recycled class PiChart
Public Property Value As Currency = 0
Public Property Name As String = "-"
Public Property ForeColor As Color = &c000000
Public Shared Function Create(Name as String, Value as Double) As PiChart
Dim p As New PiChart
p.name = Name
p.value = Value
p.foreColor = color.black
return p
End Function
Public Shared Function RandomColor() As Color
Dim myRND As New Random
Return RGB(myRND.InRange(64,255),myRND.InRange(64,255),myRND.InRange(64,255))
End Function
1 Like
Last year or so, I wanted to do that (chart as pie), then I started to work on it, drink a coffee, go back home…
and in the afternoon, a bad idea comes to ming: “What for ?”…
Copy the data, paste them in the Free LibreOffice Calc and ask for a chart…
No need to re-invent the wheel.
And so I never go back to that project again (and no one asked me for that feature !
This is free and open source, made by me years ago.
If you want more advanced features I recommend using the MBS plug-in.
It’s great, I try to see if I can adapt it to my project.
Yes I had seen it but it is too complex for my need. Thanks.
Yes, I had thought of something like this too … but since I had done it with VB6 without spending much time on it, I wondered why in Xojo there is not something more dedicated, simpler … now i will try the code of friend MarkusR 
1 Like
if you have Xojo for Web it have a build in chart (i think it use chart.js)
you can also think about using a report server, as example
ms SQL Server Reporting Services (SSRS)
or valentina studio Reporting for Xojo: Complete Reporting System for Xojo Apps
it comes a few times in year as offer.