Define and build lapsed timer - c++builder

Question

In Delphi, I understand how to build lapsing timer. But I am not sure about how to write code for C++Builder. I could not find any example.
In Delphi I wrote this code below, a copy from the source somewhere:-
....
type
TFrame2 = class(TFrame)
StatusBar1: TStatusBar;
Timer1: TTimer;
constructor TFrame2.Create(TheOwner: TComponent);
begin
inherited Create(TheOwner);
StartTime := Now;
Timer1.Enabled := True;
end;
destructor TFrame2.Destroy;
begin
inherited Destroy
end;
procedure TFrame2.Timer1Timer(Sender: TObject);//This event occurs every second.
Var
Hour, Min, Sec, MSec : Word;
Diff : TTime;
begin
Timer1.Enabled := False;
Diff := Now - StartTime;
DecodeTime(Diff, Hour, Min, Sec, MSec);
StatusBar1.Panels.Items[1].Text := IntToStr(Min)+' Minutes, '+IntToStr(Sec)+' Seconds.';
Timer1.Enabled := True;
end;
...
Please kindly how to do same in C++.
Thanks

Answer 1

Try this:
....
class TFrame2 : public TFrame
{
__published:
TStatusBar *StatusBar1;
TTimer *Timer1;
...
void __fastcall Timer1Timer(TObject *Sender);
...
private:
TDateTime StartTime;
...
public:
__fastcall TFrame2(TComponent *TheOwner);
};
__fastcall TFrame2::TFrame2(TComponent *TheOwner)
: TFrame(TheOwner)
{
StartTime = Now();
Timer1->Enabled = true;
}
void __fastcall TFrame2::Timer1Timer(TObject *Sender) //This event occurs every second.
{
Timer1->Enabled = false;
TDateTime Diff = Now() - StartTime;
Word Hour, Min, Sec, MSec;
DecodeTime(Diff, Hour, Min, Sec, MSec);
StatusBar1->Panels->Items[1]->Text = String(Min)+" Minutes, "+String(Sec)+" Seconds.";
Timer1->Enabled = true;
}
...
Alternatively, you can simplify Timer1Timer() to this:
void __fastcall TFrame2::Timer1Timer(TObject *Sender) //This event occurs every second.
{
// this is not overhead-intense code, so
// stopping and re-starting the timer
// is wasting unnecessary processing time...
//Timer1->Enabled = true;
TDateTime Diff = Now() - StartTime;
StatusBar1->Panels->Items[1]->Text = Diff.FormatString("n' Minutes, 's' Seconds.'");
//Timer1->Enabled = true;
}
Personally, I would not use the system clock at all, in case the user changes the clock, or it auto-rolls for DST, while your timer is running. I would use CPU ticks instead, either manually:
....
class TFrame2 : public TFrame
{
__published:
TStatusBar *StatusBar1;
TTimer *Timer1;
...
void __fastcall Timer1Timer(TObject *Sender);
...
private:
DWORD StartTime;
...
public:
__fastcall TFrame2(TComponent *TheOwner);
};
__fastcall TFrame2::TFrame2(TComponent *TheOwner)
: TFrame(TheOwner)
{
StartTime = GetTickCount();
Timer1->Enabled = true;
}
void __fastcall TFrame2::Timer1Timer(TObject *Sender) //This event occurs every second.
{
//Timer1->Enabled = false;
DWORD Diff = GetTickCount() - StartTime;
DWORD Mins = Diff / 60000; Diff %= 60000;
DWORD Secs = Diff / 1000;
StatusBar1->Panels->Items[1]->Text = String(Mins)+" Minutes, "+String(Secs)+" Seconds.";
//Timer1->Enabled = true;
}
...
Or via TStopWatch:
#include <System.Diagnostics.hpp>
....
class TFrame2 : public TFrame
{
__published:
TStatusBar *StatusBar1;
TTimer *Timer1;
...
void __fastcall Timer1Timer(TObject *Sender);
...
private:
TStopwatch SW;
...
public:
__fastcall TFrame2(TComponent *TheOwner);
};
__fastcall TFrame2::TFrame2(TComponent *TheOwner)
: TFrame(TheOwner)
{
SW = TStopwatch::StartNew();
Timer1->Enabled = true;
}
void __fastcall TFrame2::Timer1Timer(TObject *Sender) //This event occurs every second.
{
//Timer1->Enabled = false;
SW.Stop();
TTimeSpan TS = SW.Elapsed;
StatusBar1->Panels->Items[1]->Text = String(TS.Minutes)+" Minutes, "+String(TS.Seconds)+" Seconds.";
SW.Start();
//Timer1->Enabled = true;
}