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How can i detect that a form is al created

Posted on 1998-01-29
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Last Modified: 2010-04-04
In a MDI application i want to detect that a mdi child is
already created.
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Question by:gipa
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1 Comment
 
LVL 8

Accepted Solution

by:
ZifNab earned 100 total points
ID: 1357848
Iterate through the MDI childs and check the name.

To limit to only one mdi child, you can use this code
(from uddf)

 ChildIndex := 0
  while (ChildIndex < frmMDIParent.ChildCount) and
          (frmMDIParent.MDIChildren[ChildIndex].Name <> frmNewChild.Name) do
    Inc(ChildIndex);
  if ChildIndex = frmMDIParent.ChildCount then
    {create new child here}
    begin
       Create it...
       if no exception occurred, then show it...
    end
  else
    {child form already exists so just bring it to the top}
    frmMDIParent.MDIChildren[ChildIndex].BringToFront;

or maybe this

How about,



        if Form1 <> nil then
        begin
                Form1 := TForm1.Create(Application);
                Form1.Show;
        end;



Then in Form1's OnClose:



        Action := caFree;
        Form1    := nil;


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