Keep receiving error: expected primary-expression before ' , ' token - c++

Question

I'm kinda new to C++ however, this was a code that was provided to me and I was told to do some edits but very few. I Keep getting the error for two lines of code:
MyFrame() : wxFrame((wxFrame *)NULL, -1, wxT("wxTimerDemo " + wxDataTime::Now().Format("%c"))
, wxPoint(50,50), wxSize(500,300))
and
dc.DrawText(wxT("Testing"), 40, y);
The top one is the only code edited which was followed exactly as it should've.
Full code:
// Render timer - use of a timer
// http://wiki.wxwidgets.org/Making_a_render_loop
#include <wx/sizer.h>
#include <wx/wx.h>
#include <wx/timer.h>
// prototypes
class BasicDrawPane;
class MyFrame;
// class definitions
class RenderTimer : public wxTimer
{
BasicDrawPane* pane;
public:
RenderTimer(BasicDrawPane* pane);
void Notify();
void start();
};
#define wxT(x)
class BasicDrawPane : public wxPanel
{
public:
BasicDrawPane(wxFrame* parent);
void paintEvent(wxPaintEvent& evt);
void render( wxDC& dc );
DECLARE_EVENT_TABLE()
};
class MyApp: public wxApp
{
bool OnInit();
MyFrame* frame;
public:
};
RenderTimer::RenderTimer(BasicDrawPane* pane) : wxTimer()
{
RenderTimer::pane = pane;
}
void RenderTimer::Notify()
{
pane->Refresh();
}
void RenderTimer::start()
{
wxTimer::Start(10);
}
IMPLEMENT_APP(MyApp)
class MyFrame : public wxFrame
{
RenderTimer* timer;
BasicDrawPane* drawPane;
public:
MyFrame() : wxFrame((wxFrame *)NULL, -1, wxT("wxTimerDemo " + wxDataTime::Now().Format("%c"))
, wxPoint(50,50), wxSize(500,300))
{
drawPane = new BasicDrawPane( this );
timer = new RenderTimer(drawPane);
Show();
timer->start();
}
~MyFrame()
{
delete timer;
}
void onClose(wxCloseEvent& evt)
{
timer->Stop();
evt.Skip();
}
DECLARE_EVENT_TABLE()
};
// event table for MyFrame
BEGIN_EVENT_TABLE(MyFrame, wxFrame)
EVT_CLOSE(MyFrame::onClose)
END_EVENT_TABLE()
bool MyApp::OnInit()
{
frame = new MyFrame();
frame->Show();
return true;
}
// event table for BasicDrawPane
BEGIN_EVENT_TABLE(BasicDrawPane, wxPanel)
EVT_PAINT(BasicDrawPane::paintEvent)
END_EVENT_TABLE()
BasicDrawPane::BasicDrawPane(wxFrame* parent) :
wxPanel(parent)
{
}
void BasicDrawPane::paintEvent(wxPaintEvent& evt)
{
wxPaintDC dc(this);
render(dc);
}
void BasicDrawPane::render( wxDC& dc )
{
static int y = 0;
static int y_speed = 2;
y += y_speed;
if(y<0) y_speed = 2;
if(y>200) y_speed = -2;
dc.SetBackground( *wxWHITE_BRUSH );
dc.Clear();
dc.DrawText(wxT("Testing"), 40, y);
}
Thanks for any help.

Answer 1

#define wxT(x) transforms any x to blank.
dc.DrawText(wxT("Testing"), 40, y); becomes dc.DrawText( , 40, y); and now the error is obvious.
You should define the macro like
#define wxT(x) x
or
#define wxT(x) (x)
Defining the macro wxT is not a good use case, it should be defined when you #include <wx/string.h>, thus #define wxT(x) should be removed from your code. For more information visit #define wxT ( string ). Note that since wxWidgets 2.9.0 you shouldn't use wxT() anymore in your program sources (it was previously required if you wanted to support Unicode).