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Component - Create form now change items

Hi there,

I am writing a custom component which opens up a new form and on this form is displayed certain information
I have most of it going good however I can't seem to get the component to comunicate with the form...
Let me explain, here is my code

type
TShareReg = class(TComponent)
private
{ Private declarations }
FLocalFile : string;
FMyForm : TForm;
protected
{ Protected declarations }
public
{ Public declarations }
Constructor create(aowner:tcomponent); override;
Destructor destroy; override;
Function Execute : boolean; virtual;
published
{ Published declarations }
end;

procedure Register;

implementation

uses frmMyForm;

procedure Register;
begin
RegisterComponents('OwnComp', [TShareReg]);
end;
//==============================================================================

{ TShareReg }
constructor TShareReg.create(aowner: tcomponent);
begin
inherited create(aowner);

FMyForm := TfrmMyFrm.create(self);
end;
//==============================================================================

Now I know the form is getting created, but what I want to do is set the value of FLocalFile to a TLabel on the FMyForm.
So I tried doing
FMyForm.Label1.caption := FLocalFile;

But I get undeclaired identifiyer.
So I thought I could do that on the OnCreate event for FMyForm... but that fails also.

What am I missing

kenpem

hmmm....is Caption a private property, maybe? Even so, within the OnCreate of the MyForm should work (you did first call inherited, right?).

wildzero

ASKER

Explain :-)

The OnCreate of MyForm I should call Inherited? The MyForm is just a TForm which has componets etc on it.... wouldn't think I would need to call inherited...

ASKER CERTIFIED SOLUTION

TName

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TName

Have you tried using frmMyFrm (wich probably is declared as TfrmMyFrm in frmMyForm.pas):

frmMyForm.Label1.Caption;

TName

I mean
frmMyForm.Label1.Caption:= FLocalFile;

TName

one "o" too many:
frmMyFrm.Label1.Caption:= FLocalFile;

should have c&p-ed instead of typing... ;)

wildzero

ASKER

Testing now - so far looks good. Standby.

wildzero

ASKER

Drat, for some reason I am now getting an access violation error in rtl70.bpl...
Get this when I open the project which has my component in it....

wildzero

ASKER

frmMyFrm.Label1.Caption:= FLocalFile;
that didn't work (caused that above error)

TfrmMyFrm(FMyForm).Label1.caption := FLocalFile;
that worked :-)

wildzero

ASKER

Thanks guys!

TName

Thanks for the points! ;)

Your initial code didn't work because FMyForm is declared as TForm instead of TfrmMyFrm.
If you declare it like this: FMyForm:TfrmMyFrm; *and* move the "uses frmMyForm;" to the top (beginning of interface section) it should work without the need to typecast it.

>frmMyFrm.Label1.Caption:= FLocalFile;
>that didn't work (caused that above error)
Did you create frmMyFrm without redeclaring it (it's already declared in frmMyForm.pas)?
I just had to try it, and this works for me (I simply created a TShareReg instance in a project):

constructor TShareReg.create(aOwner: tcomponent);
begin
inherited create(aOwner);
FLocalFile:='SomeFileName';
frmMyFrm:=TfrmMyFrm.create(self);
frmMyFrm.Show; //just to test it
frmMyFrm.Label1.Caption:=FLocalFile;
end;