Question

How can I tell which nodes in my tree are visible to the user?

When the user expands a node, I would like to be able to adjust the display so that all the sub-nodes of that node are visible (without the user having to scroll up or down to see them).

Or is there a way of getting the Gant control to adjust the display automatically? I would ideally like the tree to work like the tree in Windows Explorer.

Answer

Both the phGantTimePackage and GTP.NET returns a rectangle of -1,-1,-1,-1 for the grid rect of cells that has not been drawn (because they are not currently on screen).

In phGantTimePackage you can use the IphGantRow3.GetRect method
and in GTP.NET you would use GridNode.Rect

The same applies to individual cells (that they return a -1 rect if not currently on screen).

Question

how do I set the scaler so that it shows only the days ma/tue/ etc… and that it does not scale otherwise (no hours / minutes /weeks or months) ???

Answer

phGant VCL version

First you need to find a Scale that you like presentation wise. Once you have it (Check the phGantt.Scale property in runtime when you have the Gantt set the way you want).

Use the decided scale value in the DateScaler.OnLimitScaling event. Simply return false when the Scale value differs from your constant.

Question

When i populate the gant control, i am using the UserIntegerReference property to hold the primary key value for each database record that i add to the control. As each timebar record is added to the gant, i also record the value in a cursor with its “current dates”.

When a user moves or resizes a timebar, how do I determine the UserIntegerReference value of the selected timebar? I need to take that value and lookup the assigned “UserIntegerReference” value in my database, in order to perform some validations and to show additional data.

In the OnValueChangedGantTime method, I want to use this “UserIntegerReference” to perform the lookup. But i am missing the obvious. Can you help?

Answer

The OnValueChangedGantTime gives you a parameter named theDataEntity, of the type IphdataEntity_GantTime.

If you store your db-key in the UserIntegerReference you can access it with theDataEntity.UserIntegerReference.

If you stored the key in the tree nodes UserIntegerReference you can access it like this:
((theDataEntity as IphDataEntity_GantTime2).Row as IphGantRow3).TreeNode.UserIntegerReference

Question

Using phGantTime and printing. We have text displayed in the time object. If the object is small then the text is truncated and cannot be seen on a printout. Is there anyway the text can be placed outside the time object so when a print is performed the whole text can be seen?

Answer

The latest patch has new functionality to render time item texts outside their time items.

You go like this to use it:

Private Sub addRow(textplacex As TxTextRectPlace, textplacey As TxTextRectPlace)
Dim de As IphDataEntity_Tree
Dim gr As IphGantRow3
Dim gt As IphDataEntity_GantTime2

If phGantX1.CurrentDataEntityTree Is Nothing Then
    Set de = phGantX1.AddRootDataEntityTree
  Else
    Set de = phGantX1.AddDataEntityTree(phGantX1.CurrentDataEntityTree)
  End If
 
  i = i + 1
  de.Text = “<new row>” + Str(i)
  Set gr = de.GantRow
  gr.TimeItems_CanChangeRow = False
  gr.TimeItems_CanMove = True
 
  Set gt = phGantX1.AddGantTime(de, 0)
  gt.Style = tsNormal
  gt.Start = Date
  gt.Stop = Date + 5
 
  gt.TimeItemsTextAdd
  gt.TimeItemsTextSetEx 0, de.Text, 2, 2, 0, textplacex, textplacey
         

End Sub

And the TxTextRectPlace type can have these values trpInside,trpOutsideNear,trpOutsideFar