"Available Form:". Original Delphi Frames with Original unit - delphi

Question

Problem:
How can I load frame in Form1 or sample container in form ?
FindClass or GetClass is only locality for main form appl-n
I need (maybe) string globaly elemental for TFrameClass, next code:
unit Unit1;
interface
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs,
Vcl.StdCtrls, Vcl.ExtCtrls;
type
TFrameClass = class of TFrame;
type
TForm1 = class(TForm)
Panel1: TPanel;
Button1: TButton;
procedure Button1Click(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
FFrame: TFrame;
function StrShowFrame(FrameClassName: string;
ParentPanel: TWinControl): Boolean;
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
uses Base1Frame, Base2Frame, Base3Frame;
function TForm1.StrShowFrame(FrameClassName: string;
ParentPanel: TWinControl): Boolean;
var
FrameClass: TClass;
// Current Frame (FrameName)
FrameName: string;
begin
Result := False;
??? GetClass is only locality for main form in appl-n
FrameClass := GetClass(FrameClassName);
if FrameClass = nil then
begin
ShowMessageFmt('Class %s not registered', [FrameClassName]);
Result := False;
Exit;
end;
try
begin
LockWindowUpdate(ParentPanel.Handle);
if Assigned(FFrame) then
if FFrame.ClassType = FrameClass then
begin
Result := True;
Exit;
end
else
FFrame.Destroy; // del previus FrameClass
try
FFrame := TFrameClass(FrameClass).Create(nil);
except
on E:Exception do
begin
Result := True;
E.Create(E.Message);
FFrame := nil;
Exit;
end;
end;
FrameName:= FrameClassName;
Delete(FrameName, 1, 1); // T-...
FFrame.Name := Concat(FrameName, '1');
FFrame.Parent := ParentPanel;
FFrame.Align := alClient;
end;
finally
LockWindowUpdate(0);
end;
Result := True;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
StrShowFrame('TFr_Base1', Panel1);
end;
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
try
if FFrame <> nil then
FFrame.Free
else
ShowMessage('Class not activ');
except
end;
end;
end.
How can I load frame in Form1 or sample container in form ?
FindClass or GetClass is only locality for main form appl-n
I need (maybe) string globaly elemental for TFrameClass.

Answer 1

GetClass() and FindClass() are not local to the MainForm, they are global to the entire RTL as a whole. Any unit can call RegisterClass() and have that class be accessible to any other unit that shares the same instance of the RTL. That last part is important. A DLL cannot register a class that the EXE uses (and vice versa), unless both projects are compiled with Runtime Packages enabled so they share a single RTL instance.