Can't cope with expected identifier - c++

Question

I'm making a tetris. Well, my glass (QtGlass.h) creates a figure.
I would like to use a parameter here to specify which shape the figure should
take.
Could you suggest me why parameters cause this error:
QtGlass.h:29:23: error: expected identifier before 'L'
QtGlass.h:29:23: error: expected ',' or '...' before 'L'
I've shown in the comments below where this error occurs.
By the way, if I uncomment the lines which signigy a parameterless variant,
it works.
**Figure.h**
class Figure : public QObject {
Q_OBJECT
...
public:
Figure(char Shape);
//Figure();
...
};
**Figure.cpp**
Figure::Figure(char Shape) {
//Figure::Figure() {
previous_shape = 1;
colour = RED;
...
}
**QtGlass.h**
class QtGlass : public QFrame {
Q_OBJECT
...
protected:
Figure the_figure('L'); //QtGlass.h:29:23: error: expected identifier before 'L' QtGlass.h:29:23: error: expected ',' or '...' before 'L'
//Figure the_figure;
...
};
Edded later
When I use this:
class QtGlass : public QFrame {
Q_OBJECT
QtGlass() : the_figure('L') {}
I get this:
QtGlass.cpp:164:50: error: no matching function for call to 'Figure::Figure()'
QtGlass.cpp:164:50: note: candidates are:
Figure.h:38:5: note: Figure::Figure(char)
Figure.h:38:5: note: candidate expects 1 argument, 0 provided
Figure.h:20:7: note: Figure::Figure(const Figure&)
Figure.h:20:7: note: candidate expects 1 argument, 0 provided
QtGlass.cpp
QtGlass::QtGlass(QWidget *parent) : QFrame(parent) {
key_pressed = false;
coord_x = 5;
coord_y = 5;
arrow_n = 0;
highest_line = 21;
this->initialize_glass();
QTimer *timer = new QTimer(this);
connect(timer, SIGNAL(timeout()), this, SLOT(moveDownByTimer()));
timer->start(1000);
}

Answer 1

You can't initialize a member object using that syntax. If your compiler supports C++11's uniform initialization syntax or in-class initialization of member variables you can do this:
class QtGlass : public QFrame {
Q_OBJECT
...
protected:
Figure the_figure{'L'};
// or
Figure the_figure = 'L'; // works because Figure(char) is not explicit
...
};
Otherwise you need to initialize the object within QtGlass' constructor initializer list
class QtGlass : public QFrame {
Q_OBJECT
...
protected:
Figure the_figure;
...
};
// in QtGlass.cpp
QtGlass::QtGlass(QWidget *parent)
: QFrame(parent)
, the_figure('L')
{}

Answer 2

You are trying to create an instance of Figure in the definition of QtGlass which is not allowed. You have to instantiate the_figure in the constructor of QtGlass:
class QtGlass : public QFrame {
Q_OBJECT
QtGlass() {
the_figure = Figure('L');
};
...
protected:
Figure the_figure;
...
};