QT画线(记录一下)

#include "mainwindow.h"

#include "ui_mainwindow.h"

#include 

#include 

MainWindow::MainWindow(QWidget *parent)

    : QMainWindow(parent)

    , ui(new Ui::MainWindow)

{

    ui->setupUi(this);

    //ui->pushButton->resize(width(),height());

    qDebug()<pushButton->pos().x();

}

MainWindow::~MainWindow()

{

    delete ui;

}

void MainWindow::paintEvent(QPaintEvent *)

{

    QPainter painter(this);

    QPen pen(QColor(255,0,0));

    painter.setPen(pen);

    QVectordata1{{100,100},{100,200},{300,200},{300,400}} ;

    for (int i = 1; i < data1.count(); ++i)

    {

        //painter.drawLine(data1.at(i - 1), data1.at(i));

        painter.drawLine(data1[i-1],data1[i]);

    }