Icon View Thread

The following is the text of the current message along with any replies.
Messages 1 to 10 of 11 total
Thread embedded forms
Sun, Aug 31 2014 2:27 AMPermanent Link

Harry de Boer

Hi

I wonder how it's possible that the 'same' embedded form is shown if you do this

procedure TForm1.frmGeelClick(Sender: TObject);
var
  frmGeel: TfrmGeel;
begin
  frmGeel:=TfrmGeel.Create(pnlDock);
  frmGeel.Show;
end;

I thought the second time I would get an error (form already exists - already created), but yet another form is shown each time this prcedure is executed.

How can you check if a Form already is created to show it just once?

Regards, Harry
Sun, Aug 31 2014 5:31 AMPermanent Link

Ronald

Hi Harry,

I would make the frmGeel global for the parentform (TForm1) and set the
initial value at nil. Then you can check if the form is already created
with:

if not Assigned(frmGeel) then frmGeel:=TfrmGeel.Create(pnlDock) else
frmGeel.Show;

Greetings,
Ronald

"Harry de Boer" schreef in bericht
news:FB012EF7-42DB-492D-8DC8-315A69D80B85@news.elevatesoft.com...

Hi

I wonder how it's possible that the 'same' embedded form is shown if you do
this

procedure TForm1.frmGeelClick(Sender: TObject);
var
  frmGeel: TfrmGeel;
begin
  frmGeel:=TfrmGeel.Create(pnlDock);
  frmGeel.Show;
end;

I thought the second time I would get an error (form already exists -
already created), but yet another form is shown each time this prcedure is
executed.

How can you check if a Form already is created to show it just once?

Regards, Harry
Sun, Aug 31 2014 6:22 AMPermanent Link

Harry de Boer

>>I would make the frmGeel global for the parentform (TForm1) and set the
initial value at nil.

Hi Ronald,

where and how do I exactly do that?

Regards, Harry
Sun, Aug 31 2014 5:07 PMPermanent Link

Jeff Cook

Aspect Systems Ltd

Avatar

On 31/08/2014 10:22 p.m., Harry de Boer wrote:
>>> I would make the frmGeel global for the parentform (TForm1) and set the
> initial value at nil.
>
> Hi Ronald,
>
> where and how do I exactly do that?
>
> Regards, Harry
>

Hi Harry

From a EWB raw beginner ...

From Delphi experience, I would take the "frmGeel: TfrmGeel;" out of
the frmGeelClick event and put it in the Private declarations of TForm1.
 Then in FormCreate put "frmGeel:=nil;" and use the code as per
Ronald's reply.

HTH

Cheers

Jeff
Mon, Sep 1 2014 1:55 AMPermanent Link

Harry de Boer

>> From Delphi experience, I would take the "frmGeel: TfrmGeel;" out of
the frmGeelClick event and put it in the Private declarations of TForm1.
 Then in FormCreate put "frmGeel:=nil;" and use the code as per
Ronald's reply.

Hi Jeff,

I tried -besides the := nil in form.create- putting frmGeel : TfrmGeel in the:
- private declarations of the form (error: referenced type does not exists)
- in a var declaration of the interface section (error: referenced type does not exists)
- in a var declaration of the implementation section (multiple forms can appear, - what I want to prevent)

Regards, Harry
Mon, Sep 1 2014 4:24 AMPermanent Link

Matthew Jones

Harry de Boer wrote:

> interface section (error: referenced type does not exists)

That error is because the form type you are referencing does not exist
in the current unit, so you must add the unit it is defined in to the
uses clause above the use. Most forms will have a global variable
defined for them automatically, so you just need to add the form's unit
to the uses clauses and you can access it.

This is basic Delphi programming, so once you have it understood you
will be going much faster to your goal.


--

Matthew Jones
Mon, Sep 1 2014 11:52 AMPermanent Link

Harry de Boer

"Matthew Jones" wrote:

That error is because the form type you are referencing does not exist
in the current unit, so you must add the unit it is defined in to the
uses clause above the use. Most forms will have a global variable
defined for them automatically, so you just need to add the form's unit
to the uses clauses and you can access it.

This is basic Delphi programming, so once you have it understood you
will be going much faster to your goal.

Hi Matthew,

it's been a long time ago since I worked with OP in Delphi, however I tried putting the unit in the uses clause but it does not work. Are you sure in EWB this is also possible? C

Regards, Harry  
Mon, Sep 1 2014 12:18 PMPermanent Link

Matthew Jones

Harry de Boer wrote:

> it's been a long time ago since I worked with OP in Delphi, however I
> tried putting the unit in the uses clause but it does not work. Are
> you sure in EWB this is also possible? C

Certainly does for me! If you want to post code then please do, but you
may be best to check the demos and modify them to work for you too.

--

Matthew Jones
Mon, Sep 1 2014 3:24 PMPermanent Link

Harry de Boer

Hi Matthew

I came up with this little testproject (looked at the embeddedform demo) but I can't get it to work, I must be missing something. Any help would be appreciated.

Regards, Harry



Attachments: test.zip
Mon, Sep 1 2014 4:45 PMPermanent Link

Raul

Globestar Systems

Team Elevate Team Elevate

On 9/1/2014 3:24 PM, Harry de Boer wrote:
> I came up with this little testproject (looked at the embeddedform demo) but I can't get it to work, I must be missing something. Any help would be appreciated.

Harry,

Your form 2 is being auto-created so first under Project -> Options ->
Forms move Form2 into "available forms". You don't want it to be
auto-created since you'll be creating and embedding it yourself.

That should fix the issue of form not appearing embedded.

However to make this "nicer" you can do few other things:

Unit2 already contains the default form definition (var Form2: TForm2Wink
so you can use that if you need "single instance" - it basically works
as global variable

hence you can completely remove the Form2:Tform2; declaration from unit 1.

If you want the embedding to look cleaner then on form 2 set
showcaption=false, showborder=false, showshadow=false and dock=sdtFill

This should result in form2 fully filling the panel.

Raul



Page 1 of 2Next Page
Jump to Page:  1 2
Image