How to parent QPainter to QTabWidget?

centra

Hi!

I'm creating paint software which has tabs with Qt.
I want to add the QPainter to each tab(Created with the QTabWidget).
But the QPainter's function doesn't have the "QWidget *parent" property.
How should I do?
(I'm Japanese, so please forgive my poor English.)

mrjj

Hi
Use a custom widget for each tab so you can override paintEvent.

#include <QPainter>
#include <QWidget>

class Canvas : public QWidget
{
    Q_OBJECT
public:
    explicit Canvas(QWidget *parent = nullptr) : QWidget(parent)
    {

    }
protected:
    virtual void paintEvent(QPaintEvent *event) override
    {
        QPainter p(this);
        p.drawRect(0, 0, 100, 100);
    }
};

Christian Ehrlicher

You can't attach a painter to something. You can create a QPainter in the QWidget::paintEvent() to draw on the widget.

mrjj

Hi
Use a custom widget for each tab so you can override paintEvent.

#include <QPainter>
#include <QWidget>

class Canvas : public QWidget
{
    Q_OBJECT
public:
    explicit Canvas(QWidget *parent = nullptr) : QWidget(parent)
    {

    }
protected:
    virtual void paintEvent(QPaintEvent *event) override
    {
        QPainter p(this);
        p.drawRect(0, 0, 100, 100);
    }
};

centra

I've got the thing I want to do. Thanks a lot!