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problem declaring new painting class
Hi I'm trying to create class whith would paint something
but I get some errors when i try to compile it:
there is my files
pt.h
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Source code
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#ifndef TARGET_H
#defineTARGET_H
class target {
public:
target();
virtual ~target();
void paintTarget(QPainter &painter);
private:
};
#endif
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pt.cpp
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Source code
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#include "target.h"
target::target()
{}
target::~target() {}
void target::paintTarget(QPainter &painter)
{
painter.setPen(Qt::blue,2);
painter.setBrush(Qt::yellow);
painter.drawEllipse(100,100,10,10);
}
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i call it in another class using QPainter
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private:
target trgt;
...
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void plot::paintEvent(QPaintEvent* )
{
QPainter painter(this);
trgt.paintTarget(painter);
}
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error:
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Source code
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In file included from pt.cpp:1:
pt.h:8: error: 'QPainter' has not been declared
pt.cpp:6: error: variable or field 'paintTarget' declared void
pt.cpp:6: error: 'QPainter' was not declared in this scope
pt.cpp:6: error: 'painter' was not declared in this scope
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Where is mistake?
compiler tells you pretty plainly. What this has to do with Qt I don't really know.
#ifndef TARGET_H
#defineTARGET_H
class target {
public:
target();
virtual ~target();
void paintTarget(QPainter &painter);
private:
};
#endif
pt.h:8: error: 'QPainter' has not been declared
If you have a problem, CUT and PASTE your code. Do not retype or simplify it. Give a COMPLETE and COMPILABLE example of your problem. Otherwise we are all guessing the problem from a fabrication where relevant details are often missing.
so i heve to include qpainter to this clss or there is other way to correct the mistake?
In your header, if you use QPainter* or QPainter& const, then you can just forward declare it. But if you use QPainter& or QPainter, then you must #include.
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class QPainter;
....
class xxx
{
void paintTarget(QPainter& const painter);
}
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OR
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Source code
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#include <QPainter>
....
class xxx
{
void paintTarget(QPainter& painter);
}
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If you have a problem, CUT and PASTE your code. Do not retype or simplify it. Give a COMPLETE and COMPILABLE example of your problem. Otherwise we are all guessing the problem from a fabrication where relevant details are often missing.
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painting in QWidget
(Dec 10th 2011, 12:23pm)
