Array question

[td]

Hi,

I have a qwidget, that has as a member a 2-D array of ints. Now I'm having trouble accessing the vales in member functions of the widget.

// the .h file
class holdingWidget : public QWidget
{
	    Q_OBJECT
.
.
.
.
protected: 
		void paintEvent(QPaintEvent *ev);
 
private:
		int myArrayOne[44][3];

// the .h file
class holdingWidget : public QWidget
{
	    Q_OBJECT
.
.
.
.
protected: 
		void paintEvent(QPaintEvent *ev);

private:
		int myArrayOne[44][3];

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Now in the class defintion

holdingWidget::holdingWidget(QWidget* parent): QWidget(parent)
{
int myArrayOne[44][3] =....
.
.
.
}
 
void holdingWidget::paintEvent(QPaintEvent *ev)
{
.
.
int k = myArrayOne[0][0];
int l = myArrayOne[0][1];
}

holdingWidget::holdingWidget(QWidget* parent): QWidget(parent)
{
int myArrayOne[44][3] =....
.
.
.
}

void holdingWidget::paintEvent(QPaintEvent *ev)
{
.
.
int k = myArrayOne[0][0];
int l = myArrayOne[0][1];
}

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Now in the paintEvent the values are nonsense numbers and not the ones I specified above. But if I define the array in the paintevent it works ok. What am I missing here? Any help appreciated.

[PaceyIV]

You define the int myArrayOne[44][3]; in the class header, so in the constructor you don't have to re-define myArrayOne.
myArrayOne defined in the constructor is a private variable visible only in the constructor. It is different from the one defined in the class as private member.

try

holdingWidget::holdingWidget(QWidget* parent): QWidget(parent)
{
    for (int r=0; r < 44; ++r)
        for (int c=0; c<3; ++c)
               myArrayOne[r][c] = 1;
 
 
}

holdingWidget::holdingWidget(QWidget* parent): QWidget(parent)
{
    for (int r=0; r < 44; ++r)
        for (int c=0; c<3; ++c)
               myArrayOne[r][c] = 1;


}

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EDIT: There was a trivial error

[td]

Ah I knew it would be something stupid like that that I'd miss! Thanks a lot. Works now.

[td]

Ok so when initialising the array

for(int i=0;i<44;i++)
{
		for(int j=0;j<3;j++)
		{
			qDebug() << "For  " << i << " - " << j;
			myArrayOne[i][j] = 1;
			qDebug() << myArrayOne[i][j];
		}
}

for(int i=0;i<44;i++)
{
		for(int j=0;j<3;j++)
		{
			qDebug() << "For  " << i << " - " << j;
			myArrayOne[i][j] = 1;
			qDebug() << myArrayOne[i][j];
		}
}

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The program won't build and crashes. Get the following error

Unhandled exception at 0x6703f24c (QtCored4.dll) in myProgram.exe: 0xC0000005: Access violation reading location 0x00000035.

Any ideas?

[PaceyIV]

Use the debugger.
I don't think that the error you reported it's here!

[Boron]

And give your class an upper case first letter.

class HoldingWidget

class HoldingWidget

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It's a world wide accepted convention to do this .