mdi的问题???(20分)

L

littlecaibird

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2003-07-09

• #1

procedure TForm1.CreateMDIChild;
var
Child:TForm3;
begin
Child:=TForm3.Create(Application);
end;

procedure TForm1.SpeedButton1Click(Sender: TObject);
begin
CreateMDIChild;
end;

要求：
当存子窗体存在时，按下SpeedButton1不起作用,
当半闭这个窗体后，再按SpeedButton1就让子体出来??

就是要判断出这个子窗体如果存在，那不就不要再建立,
否则建立

 

L

littlecaibird

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2003-07-09

• #2

怎么才能实现啊？
要不会按一下按钮就产生一个窗体，会产生好多的！！！
我只想产生一个，还在如果关闭怎么释放内存！！！

 

H

hongwei

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2003-07-09

• #3

procedure TForm1.CreateMDIChild;
var
Child:TForm3;
begin
try
if Child=nill then//判断
Child:=TForm3.Create(self);
child.showmodel;//显示
finally
freeandnil(child);//释放
end;
end;

 

S

stuwe

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2003-07-09

• #4

procedure OpenForm(FormClass: TFormClass; var fm; AOwner: TComponent);
var i:Integer;
Child:TForm;
begin
for i:=0 to Screen.FormCount-1 do
if Screen.Forms.ClassType=FormClass then
begin
Child:=Screen.Forms;
if Child.WindowState=wsMinimized then
ShowWindow(Child.Handle,3);
if (not Child.Visible) then Child.Visible:=true;
Child.BringToFront;
Child.SetFocus;
TForm(fm):=Child;
exit
end;
Child:=TForm(FormClass.NewInstance);
TForm(fm):=Child;
Child.Create(AOwner);
end;

 

蒋

蒋劲刚

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2003-07-09

• #5

在CHILD窗体的ONCLOSE中加上ACTION:=CAFREE就可以在关闭窗体时自动释放