QT--绘制正弦波与余弦波切换视图

我就是我 2023-07-12 03:49 33阅读 0赞

#ifndef WIDGET_H
    #define WIDGET_H
    
    #include <QtGui/QWidget>
    #include <QTimer>
    #include <QPushButton>
    
    class Widget : public QWidget
    { 
        Q_OBJECT
    private:
        QTimer *t1;
        int count;
        QPushButton *btn_sin;
        QPushButton *btn_cos;
    public slots:
        void handleTimeoue();
    protected:
        void paintEvent(QPaintEvent *);
    public:
        Widget(QWidget *parent = 0);
        ~Widget();
    
    
    };
    
    #endif // WIDGET_H
    #include "Widget.h"
    #include <QPainter>
    #include <QPointF>
    #include <QPen>
    #include <qmath.h>
    #include <QTimer>
    #include <QDebug>
    #include <QPushButton>
    Widget::Widget(QWidget *parent)
        : QWidget(parent),count(0)
    { 
    // btn_sin = new QPushButton(this);
    // btn_sin->move(10,0);
    // btn_sin->setText("Sin");
    
        t1 = new QTimer(this);
        connect(t1,SIGNAL(timeout()),this,SLOT(handleTimeoue()));
        t1->start(1000);
    
    
    }
    void Widget::handleTimeoue()
    { 
        count++;
        count = count % 2;
        update();
        qDebug() << "Widget::handleTimeoue()"<<count;
    }
    void Widget::paintEvent(QPaintEvent *)
    { 
        QPainter painter(this);
        QPen pen;
    
        pen.setColor(Qt::green);
        pen.setStyle(Qt::SolidLine);
        pen.setWidthF(0.01);
    
        painter.setPen(pen);
    
        painter.setViewport(50, 50, width()-100, height()-100);
        painter.setWindow(-10, 2, 20, -4); // (-10, 2) (10, -2)
    
        painter.fillRect(-10, 2, 20, -4, Qt::black);
    
        painter.drawLine(QPointF(-10, 0), QPointF(10, 0));   // x
        painter.drawLine(QPointF(0, 2), QPointF(0, -2));     // y
        if(count == 1)
        { 
           for(float x=-10; x<10; x+=0.01)
           { 
               float y = qSin(x);
    
               painter.drawPoint(QPointF(x, y));
           }
        }
        else if(count == 0 )
        { 
            for(float x= -10; x<10; x+=0.01)
            { 
                float y = qCos(x);
                painter.drawPoint(QPointF(x, y));
            }
        }
    }
    
    Widget::~Widget()
    { 
        
    }
    #include <QtGui/QApplication>
    #include "Widget.h"
    
    int main(int argc, char *argv[])
    { 
        QApplication a(argc, argv);
        Widget w;
        w.show();
        
        return a.exec();
    }