[Solved] Runtime creating controls in new Tab in PageControl
lazarus / 31-LCL

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pebe · 2022-02-19 18:42

Hi.

I am in the process of creating a program that retrieves information
about the contents of a bookmark from an INI file.

I have successfully created a new tab:
Code: [Select]    actionList.Clear;
    conf.ReadSectionValues(section,actionList);
    if actionList.Count>0 then
    begin
      page:=PageControl1.AddTabSheet;
      page.Visible:=True;
      page.AutoSize:=True;
      page.Caption:=actionGroup.Items[actionGroup.ItemIndex];
      makePage(page);
      PageControl1.ActivePage:=page;
      self.DoAutoSize;
      closeForm:=false;
    end;

The procedure that generates its contents looks as follows:
Code: [Select]var
  actLine:integer;          // actual line in INI section
  elType,elParams:String;   // element type (from INI section key) and
element parameters (from key value)
  elValue:TStringList;
  eLabel:TLabel;            // variables for new components
  eRadiobutton:TRadioButton;
  eCheckBox:TCheckBox;
  eInput:TEdit;
  i:Integer;                // help variable

begin
  actLine:=0;

  while actLine<actionList.Count-1 do
  begin
    // take line from INI section
    elType:=trim(actionList[actLine]); inc(actLine);

    // split key as a element type and key value as a element
parameters
    i:=Pos('=',elType);
    if i>0 then
    begin
      elParams:=copy(elType,i+1);
      elType:=copy(elType,1,i);
    end
    else
      elParams:='';

    // split parameters to array of string
    elValue:=TStringList.Create;
    elValue.AddDelimitedText(elParams,',',True);

    case elType of
      'label':
        begin
          with TLabel.Create(tabSheet) do
          begin
            Align:=alTop;
            Autosize:=true;
            Parent:=tabSheet;
            Caption:=elValue[0];    // first parameter is label
content
          end;
        end;
      'radiobutton':
        begin
          with TRadioButton.Create(tabSheet) do
          begin
            // first parameter is Name, but is not used
            Align:=alTop;
            Parent:=tabSheet;
            Caption:=elValue[1];    // secound parameter is Caption
            Tag:=actLine;
          end;
        end;
      'checkbox':
        begin
          with TCheckbox.Create(tabSheet) do
          begin
            Align:=alTop;
            Parent:=tabSheet;
            Caption:=elValue[1];
            Tag:=actLine;
          end;
        end;
      'input':
        begin
          with TEdit.Create(tabSheet) do
          begin
            Align:=alTop;
            Parent:=tabSheet;
            Tag:=actLine;
          end;
        end;
    end;

    elValue.Free;
  end;
end;
The code is not the most beautiful, but it was written on the fly

Example INI Section:
Code: [Select]label="Krok 1."
radiobutton="Found","Pojazd przypisany do OBU"
checkbox="TollPass","Znaleziony w TollPass"
input=TP-LPN,Rejestracja pojazdu:
checkBox="O","Znaleziony w Outlooku"
input=OLPN,Rejestracja pojazdu:
radiobutton="Not Found',"Brak pojazdu z przypisanym OBU"
next=close

Unfortunately, after creating the content, nothing shows up for me in
the Tab. What I don't know about is what needs to be done to make the
contents of the bookmark visible. I send the expected view in the
attachment.

The form in which the PageControl is located is of modal type, but
that doesn't seem to matter much.
What I'd like is for the elements that are created in the tab, to be
automatically aligned is the top of the tab (hence 'Align:=alTop') and
be placed one below the other.

The whole window is supposed to adjust in size to the number of
components in the tab - this is where I found the TForm.doAutosize
procedure, which seems to work. I execute it at the end of creating
the tab content.

Please Help.

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pebe · 2022-02-19 20:17

OK. I found my mistake.

The error was trivial and hid in the logic of dealing with the INI
line. I copied one character too many to the element type, which
caused the later "Case" to not detect the element.

There was one more aspect. I had to set the 'Top' attribute for each
element, because without it, the form was created "upside down".

It's OK now. I can develop my idea further.