Hola.
Derivando de un
TPanel te hice un ejemplo básico como para que puedas ir trabajando sobre él:
Código PHP:
...
class TPanelClear : public TPanel {
protected:
void __fastcall CreateParams( TCreateParams &Params ) {
TPanel::CreateParams( Params );
Params.ExStyle |= WS_EX_TRANSPARENT;
}
void __fastcall Paint() {
HDC DC = Canvas->Handle;
TRect R = ClientRect;
Graphics::TBitmap *BM = new Graphics::TBitmap;
try {
BM->Height = Height;
BM->Width = Width;
Canvas->Handle = BM->Canvas->Handle;
TPanel::Paint();
Canvas->Handle = DC;
Canvas->Brush->Style = bsClear;
Canvas->BrushCopy(R, BM, R, Color);
}
__finally {
delete BM;
}
}
public:
__fastcall TPanelClear( TComponent *Owner ) : TPanel( Owner ) {
// ...
}
// ...
};
void __fastcall TForm1::btShowPanelClearClick(TObject *Sender)
{
TPanelClear *pc = new TPanelClear(this);
pc->Left = 5;
pc->Top = 5;
pc->Height = 50;
pc->Width = 200;
pc->Name = "PanelClear1";
pc->Caption = pc->Name;
pc->Parent = this;
}
Muestra:
Saludos