#include "widget.h"
#include "ui_widget.h"

#include <QEvent>
#include <QDebug>
#include <QPainter>

class MyPaintFilter : public QObject {
private:
    QWidget* w;
public:
    MyPaintFilter(QWidget* _w) : w(_w), QObject() {}
    bool eventFilter(QObject *, QEvent *e) {
        if (e->type() == QEvent::Paint) {
            QPainter p(w);
            p.drawText(200,100, "Another text");
//            return true;
        }
        return false;
    }
};

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
    this->installEventFilter(new MyPaintFilter(this));
}

Widget::~Widget()
{
    delete ui;
}

void Widget::paintEvent(QPaintEvent *e) {
    QPainter p(this);
    p.drawText(100, 100,"Some text");
}