Different series name and legend entries.

[TonyVSUK]

Hello all,

I have a situation where I want to call a series one thing (for example, <data item>, <source file>, <axis>), but want something else to appear in the legend (eg, <data item> or some additional text relating to the data).

Is this possible at the moment? I can only seem to set the legend entry to be a certain format, but the text always shows the series title.

Many thanks in advance,

Tony.

[Yeray]

Hi Tony,

You could use OnGetLegendText to personalize legend's text:

Code: Select all

Private Sub Form_Load()
  TeeCommander1.Chart = TChart1
  
  Dim i As Integer
  For i = 0 To 5
    TChart1.AddSeries scPoint
    TChart1.Series(i).FillSampleValues 5
  Next i
End Sub


Private Sub TChart1_OnGetLegendText(ByVal LegendStyle As Long, ByVal ValueIndex As Long, LegendText As String)
  Select Case ValueIndex
    Case 0: LegendText = "My first item"
    Case 1: LegendText = "My second item"
    Case 2: LegendText = "My third item"
    Case 3: LegendText = "My fourth item"
    Case 4: LegendText = "My fifth item"
    Case 5: LegendText = "My sixth item"
  End Select
End Sub

[TonyVSUK]

Thanks for this, I can definitely work with that.

Would it be possible in a future release to allow the editing the legend text in a TChart commander window/dialog?

Tony.

[Yeray]

Hi Tony,

Yes, we already have in the wish list the possibility to fully customize all the items (number of items, text and legend symbol) to be included in future releases.

[TonyVSUK]

Hi Tony,

Yes, we already have in the wish list the possibility to fully customize all the items (number of items, text and legend symbol) to be included in future releases.

Is this in version 8.0.0.7? I notice the CLegendItems and CLegend classes, but how would you set the legend entry when adding a series (that is the ideal time to set the legend entry)?

Many thanks,

Tony.

[Yeray]

Hi Tony,

Right now you can't manually modify the number of items on the legend. The number of items in the legend will be:
- The number of series in the chart when legendstyle is lsSeries or lsLastValues.
- The number of values in the first series when legendstyle is lsValues.
- The number of groups when legendstyle is lsSeriesGroups.

What you can change is the text of each item that is going to be displayed with OnGetLegendText as said above.

Note that with TeeChart Pro v9 VCL there will be a CustomLegendTool that will allow to customize many other things.

[TonyVSUK]

Right now you can't manually modify the number of items on the legend. The number of items in the legend will be:

That seems like the correct thing to me (and I have no need to change it).

All I want to do is create a series, give it a title, and set the legend entry for it at the same time. At the moment I need to create the series, store the legend entries, wait for the graph to draw, and then intercept "OnGetLegendText" to set the legend entries from the previous stored entries. If my users add their own plots, I lose the ability to do this as I have lost the ordering of the displayed series.

A function called "series.SetLegendText" is what I really need.

Does that make sense?

Tony.

[Yeray]

Hi Tony,

Hmmm... I'm not sure to see the sense of it. In vcl (delphi) it is possible to do:

Code: Select all

Chart1.Legend.Item[0].Text:='custom text';

But I can't see the final difference of using the OnGetLegendText to do (ActiveX, VB6):

Code: Select all

Private Sub TChart1_OnGetLegendText(ByVal LegendStyle As Long, ByVal ValueIndex As Long, LegendText As String)
  Select Case ValueIndex
    Case 0: LegendText = "custom text"
  End Select
End Sub

Could you please explain the exact steps to reproduce the problem? Maybe an simple example project we can run as-is here and/or some pictures would help us to understand what you have and what would you like to have.

[TonyVSUK]

I'll try and explain.

First, I add some plots to the graph in my code (the format is "variable", "scenario", "axis")

time, scenario 1, LHS
population[US], scenario 1, LHS
population[UK], scenario 1, LHS

And I want to set the legend entries to

Simulation Time for scenario 1, LH Axis
US Population for default scenario
UK population for default scenario

At this point, I can use OnLegendGetText to set the legend entries as I know all of those plots are "mine", and what index they are in the tchart.

Now the user adds their own plot at runtime which is the sum of the two populations. I have no control over what they call the plot. The list of series now looks like this

time, scenario 1, LHS
total population (user generated)
population[US], scenario 1, LHS
population[UK], scenario 1, LHS

I can now only use OnLegendGetText for the first series. As it is, the user generated plot would have the label entry "US Population for default scenario".

Does that make sense? All would be OK if I could set the legend entry for each series rather than use OnLegendGetText.

Tony.

[Yeray]

Hi Tony,

Couldn't you series' titles to be shown in the legend and use OnAddSeries to set a title for the series that the user will create?

Code: Select all

Private Sub Command1_Click()
  TChart1.AddSeries scLine
End Sub

Private Sub Form_Load() 
  Dim i As Integer
  For i = 0 To 1
    TChart1.AddSeries scLine
    TChart1.Series(i).FillSampleValues 5
  Next i
  
  TChart1.Series(0).Title = "US Population for default scenario"
  TChart1.Series(1).Title = "UK Population for default scenario"
End Sub

Private Sub TChart1_OnAddSeries(ByVal SeriesIndex As Long)
  If SeriesIndex = 2 Then
    TChart1.Series(SeriesIndex).Title = "total population"
    TChart1.Series(SeriesIndex).FillSampleValues 5
  End If
End Sub

[TonyVSUK]

I would still lose track of which of the plots are "mine" that way (the "population[US], scenario 1, LHS" which identifies the plot as mine is lost).

[Yeray]

Hi Tony,

Please try to arrange a simple example project we can run as-is to reproduce the problem here and we will see if we can find a solution for you.

[TonyVSUK]

There is a demo project attached to this message (it's very simple).

1. Run the project.
2. Click "Add first batch". Everything is operating normally.
3. Click "Editor". Add a new series, select "Functions" and "Add".
4. New series is now called "Series5".
5. Click "Add 2nd batch".

The legend entries are now not correct.

The only way around this at the moment is to keep a completely separate list of series legend entries, and also monitor OnSeriesAdd. All would be so much easier if you could just call something like "TChart1.Series(0).SetLegendEntry("some value")"

Tony.

[Yeray]

Hi Tony,

If I understand well, you want to check if a series was added through the editor or by code at OnGetLegendText. If so, you could use an array to save the index of the series added by code. Take a look at the modifications I made to your code:

Code: Select all

Option Explicit

Dim MySeries() As Integer
Dim NumEls As Integer

Private Sub Command1_Click()
Dim i As Integer
    NumEls = 0
    For i = 0 To 4
        TChart1.AddSeries scLine
        TChart1.Series(i).FillSampleValues 10
    Next i
    
    TChart1.Series(0).Title = "Population[US], default, LHS"
    TChart1.Series(1).Title = "Population[DE], default, LHS"
    TChart1.Series(2).Title = "Population[IE], default, LHS"
    TChart1.Series(3).Title = "Population[UK], default, LHS"
    TChart1.Series(4).Title = "Population[FR], default, LHS"
    
End Sub

Private Sub Command2_Click()
TChart1.ShowEditor
'TeeEditor1.ShowEditor
End Sub

Private Sub Command3_Click()
Dim i As Integer

    For i = 0 To 1
        TChart1.AddSeries scLine
        TChart1.Series(TChart1.SeriesCount - 1).FillSampleValues 10
    Next i
    
    TChart1.Series(TChart1.SeriesCount - 2).Title = "Population[IT], default, LHS"
    TChart1.Series(TChart1.SeriesCount - 1).Title = "Population[ES], default, LHS"
End Sub

Private Sub Command4_Click()
  TChart1.Series(0).RefreshSeries
End Sub

Private Sub TChart1_OnAddSeries(ByVal SeriesIndex As Long)
  ReDim Preserve MySeries(NumEls + 1) As Integer
  MySeries(NumEls) = SeriesIndex
  NumEls = NumEls + 1
End Sub

Private Sub TChart1_OnGetLegendText(ByVal LegendStyle As Long, ByVal ValueIndex As Long, LegendText As String)
  Dim i, MyIndex, UserCount As Integer
  UserCount = -1
  MyIndex = -1
  For i = 0 To NumEls - 1
    If MySeries(i) = ValueIndex Then
      MyIndex = i
    Else
      If MySeries(i) > ValueIndex Then
        UserCount = i
        Exit For
      End If
    End If
  Next i

  If MyIndex <> -1 Then
    Select Case MyIndex
    Case 0:
        LegendText = "US Population for default scenario"
    Case 1:
        LegendText = "DE Population for default scenario"
    Case 2:
        LegendText = "IE Population for default scenario"
    Case 3:
        LegendText = "UK Population for default scenario"
    Case 4:
        LegendText = "FR Population for default scenario"
    Case 5:
        LegendText = "IT Population for default scenario"
    Case 6:
        LegendText = "ES Population for default scenario"
    End Select
  Else
    If UserCount = -1 Then
      UserCount = NumEls
    End If
    LegendText = "user's series nº " + Str$(ValueIndex - UserCount)
  End If
End Sub

[TonyVSUK]

If I understand well, you want to check if a series was added through the editor or by code at OnGetLegendText. If so, you could use an array to save the index of the series added by code. Take a look at the modifications I made to your code:

No. Ideally, I don't want to even use OnLegendGetText.

All I want to do is set the legend entry at the time I create the series. This workaround needs more work as well as I would need to capture if someone re-orders the series (try moving the top series down after adding the user series). All would be solved if there was a function to set the legend entry for a series instead of using OnGetLegendText.

Don't spend any time adding additional code to the demo above. I won't be implementing it, I'll work out some other way of doing what I need to do.