asked on

dynamic creation of a component within a component

I've been trying to place components on a form dynamically and have got as far as the code below successfully.

What I now need to do is create the same as below BUT with a linked TUpDown control.

What I can't work out is

how to create it and more to the point link it up.

I know that I need to create the component somewhere within this procedure but I can't see where to use the TUpDown.associate property.

Note this is just code in a unit - I'm not particularly trying to create a component although that may be the way to go.

TVMIA

John

procedure DynaIBEdit(form: Tform; myparent: Twincontrol; mytop, myleft, mywidth: integer; myds: TIB_datasource; mydf:
string);
begin
with TIB_edit.Create(form) do begin
parent := myparent;
top := mytop;
left := myleft;
width := mywidth;
DataSource := myds;
datafield := mydf;
end;

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jbeh

ASKER

Unfortunately I am not quite getting the effect I am trying to acheive.

If I put the components on a form at design time as follows

inherited Ts_Edit: TTabSheet
object IB_Edit1: TIB_Edit
Left = 584
Top = 44
Width = 109
Height = 21
DataField = 'probability_of_getting'
DataSource = IB_DataSource_base
TabOrder = 1
end
object UpDown1: TUpDown
Left = 693
Top = 44
Width = 12
Height = 21
Associate = IB_Edit1
Min = 0
Increment = 5
Position = 0
TabOrder = 2
Wrap = False
OnClick = UpDown1Click
end
end

I get the functionality I need which amounts to a data aware spinner control (used for forcing integers between 0 and 100) without needing to write any events at all.

What I currently have is

procedure DynaIBspinEdit(form: Tform; myparent: Twincontrol; mytop, myleft, mywidth: integer; myds: TIB_datasource; mydf:
string);
var
UpDown : TupDown;
TibEdit : Tib_edit;
begin
TibEdit := TIB_edit.Create(form);
with TibEdit do begin
parent := myparent;
top := mytop;
left := myleft;
width := mywidth;
DataSource := myds;
datafield := mydf;
end;
UpDown := TUpDown.create(form);
with UpDown do begin
Parent := tibedit;
ArrowKeys := true;
min := 0;
max := 100;
increment := 5;
position := 0;
OnClick := UpDown.OnClick;
Associate := tibedit;
end;
end;

I'm wondering if I've got a parenting issue

UpDown := TUpDown.create(self); fails - Undeclared identifier self.

Anyway - I am very close but I'm not quite there yet..

John

geobul

Hi,
I think that UpDown.Parent should be the same as TibEdit.Parent.

Regards, Geo

geobul

Also:
OnClick := UpDown.OnClick;
seems to be wrong.

jbeh

ASKER

Geo

Hi - I'll make the changes although I think when I was playing last night I tried this to no avail.

I'll have another go anyway

Ta

John

geobul

The following work fine I think (I've used TEdit):

type
TForm1 = class(TForm)
Button1: TButton;
procedure Button1Click(Sender: TObject);
procedure DynaIBspinEdit(form: Tform; myparent: Twincontrol; mytop, myleft, mywidth: integer);
procedure UDClick(Sender: TObject; Button: TUDBtnType);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.DynaIBspinEdit(form: Tform; myparent: Twincontrol; mytop, myleft, mywidth: integer);
var
UpDown : TupDown;
TibEdit : Tedit;
begin
TibEdit := TEdit.Create(form);
with TibEdit do begin
parent := myparent;
top := mytop;
left := myleft;
width := mywidth;
// DataSource := myds;
// datafield := mydf;
end;
UpDown := TUpDown.create(form);
with UpDown do begin
Parent := myparent;
ArrowKeys := true;
min := 0;
max := 100;
increment := 5;
position := 0;
OnClick := UDClick;
Associate := tibedit;
end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
DynaIBspinEdit(Form1, Form1, 50, 50 ,100);
end;

procedure TForm1.UDClick(Sender: TObject; Button: TUDBtnType);
begin
ShowMessage('UpDown was clicked');
end;

Regards, Geo

jbeh

ASKER

Thank you Gents.

I have now got this working satisfactorily with the following code

procedure DynaIBspinEdit(form: Tform; myparent: Twincontrol; mytop, myleft, mywidth: integer; myds: TIB_datasource; mydf:
string);
var
UpDown : TupDown;
TibEdit : Tib_edit;
begin
TibEdit := TIB_edit.Create(form);
with TibEdit do begin
parent := myparent;
top := mytop;
left := myleft;
width := mywidth;
autolabel.kind := albleft;
autolabel.Options := [{albdotleader,} albonlyfirstcharupper, albboldifrequired {, albsuffixbeforedots}];
autolabel.Suffix := ' :--';
DataSource := myds;
datafield := mydf;
end;
UpDown := TUpDown.create(form);
with UpDown do begin
Parent := myparent;
ArrowKeys := true;
min := 0;
max := 100;
increment := 5;
position := 0;
wrap := true;
OnClick := OnClick;
Associate := tibedit;
end;
end;

I think part of my problem is that I had similar designed control for comparison purposes and things didn't work until I dumped it.

Truly don't understand why but there you go. :-)

I am NOT 100% sure why this has taken me so long but as I have now got it sorted I can start making progress again.

Thank you both very much.

All other things being equal I'll close this question tomorrow and pay my dues

jbeh

ASKER

Thanks all

John

geobul

I must say that your choice is not fair and will mislead people who will buy this question to use wrong code.

Regards, Geo