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QtChart.pro

+#-------------------------------------------------
+#
+# Project created by QtCreator 2017-11-16T09:53:11
+#
+#-------------------------------------------------
+
+QT       += core gui
+
+greaterThan(QT_MAJOR_VERSION, 4): QT += widgets charts serialport
+
+TARGET = QtChart
+TEMPLATE = app
+
+# The following define makes your compiler emit warnings if you use
+# any feature of Qt which has been marked as deprecated (the exact warnings
+# depend on your compiler). Please consult the documentation of the
+# deprecated API in order to know how to port your code away from it.
+DEFINES += QT_DEPRECATED_WARNINGS
+
+# You can also make your code fail to compile if you use deprecated APIs.
+# In order to do so, uncomment the following line.
+# You can also select to disable deprecated APIs only up to a certain version of Qt.
+#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
+
+
+SOURCES += \
+        main.cpp \
+        mainwidget.cpp \
+    chartview.cpp \
+    callout.cpp
+
+HEADERS += \
+        mainwidget.h \
+    chartview.h \
+    callout.h
+
+FORMS += \
+        mainwidget.ui

callout.cpp

+#include "callout.h"
+
+#include <QPainter>
+#include <QFontMetrics>
+#include <QGraphicsSceneMouseEvent>
+#include <QMouseEvent>
+#include <QChart>
+
+Callout::Callout(QChart *chart):
+    QGraphicsItem(chart),
+    chart(chart)
+{
+
+}
+
+QRectF Callout::boundingRect() const
+{
+    QPointF anchor = mapFromParent(chart->mapToPosition(this->anchor));
+    QRectF rect;
+    rect.setLeft(qMin(this->rect.left(), anchor.x()));
+    rect.setRight(qMax(this->rect.right(), anchor.x()));
+    rect.setTop(qMin(this->rect.top(), anchor.y()));
+    rect.setBottom(qMax(this->rect.bottom(), anchor.y()));
+
+    return rect;
+}
+
+void Callout::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
+{
+    Q_UNUSED(option)
+    Q_UNUSED(widget)
+
+    QPainterPath path;
+    path.addRoundedRect(rect, 5, 5);
+
+    QPointF anchor = mapFromParent(chart->mapToPosition(this->anchor));
+    if (!rect.contains(anchor)) {
+        QPointF point1, point2;
+
+        // establish the position of the anchor point in relation to rect
+        bool above = anchor.y() <= rect.top();
+        bool aboveCenter = anchor.y() > rect.top() && anchor.y() <= rect.center().y();
+        bool belowCenter = anchor.y() > rect.center().y() && anchor.y() <= rect.bottom();
+        bool below = anchor.y() > rect.bottom();
+
+        bool onLeft = anchor.x() <= rect.left();
+        bool leftOfCenter = anchor.x() > rect.left() && anchor.x() <= rect.center().x();
+        bool rightOfCenter = anchor.x() > rect.center().x() && anchor.x() <= rect.right();
+        bool onRight = anchor.x() > rect.right();
+
+        // get the nearest rect corner.
+        qreal x = (onRight + rightOfCenter) * rect.width();
+        qreal y = (below + belowCenter) * rect.height();
+        bool cornerCase = (above && onLeft) || (above && onRight) || (below && onLeft) || (below && onRight);
+        bool vertical = qAbs(anchor.x() - x) > qAbs(anchor.y() - y);
+
+        qreal x1 = x + leftOfCenter * 10 - rightOfCenter * 20 + cornerCase * !vertical * (onLeft * 10 - onRight * 20);
+        qreal y1 = y + aboveCenter * 10 - belowCenter * 20 + cornerCase * vertical * (above * 10 - below * 20);;
+        point1.setX(x1);
+        point1.setY(y1);
+
+        qreal x2 = x + leftOfCenter * 20 - rightOfCenter * 10 + cornerCase * !vertical * (onLeft * 20 - onRight * 10);;
+        qreal y2 = y + aboveCenter * 20 - belowCenter * 10 + cornerCase * vertical * (above * 20 - below * 10);;
+        point2.setX(x2);
+        point2.setY(y2);
+
+        path.moveTo(point1);
+        path.lineTo(anchor);
+        path.lineTo(point2);
+        path = path.simplified();
+    }
+
+    painter->setBrush(QColor(255, 255, 255));
+    painter->drawPath(path);
+    painter->drawText(textRect, text);
+}
+
+void Callout::mousePressEvent(QGraphicsSceneMouseEvent *event)
+{
+    event->setAccepted(true);
+}
+
+void Callout::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
+{
+    if (event->buttons() & Qt::LeftButton){
+        setPos(mapToParent(event->pos() - event->buttonDownPos(Qt::LeftButton)));
+        event->setAccepted(true);
+    } else {
+        event->setAccepted(false);
+    }
+}
+
+void Callout::setText(const QString &text)
+{
+    this->text = text;
+    QFontMetrics metrics(font);
+    textRect = metrics.boundingRect(QRect(0, 0, 150, 150), Qt::AlignLeft, text);
+    textRect.translate(5, 5);
+    prepareGeometryChange();
+    rect = textRect.adjusted(-5, -5, 5, 5);
+}
+
+void Callout::setAnchor(QPointF point)
+{
+    anchor = point;
+}
+
+void Callout::updateGeometry()
+{
+    prepareGeometryChange();
+    setPos(chart->mapToPosition(anchor) + QPoint(10, -50));
+}

callout.h

+#ifndef __CALLOUT_H__
+#define __CALLOUT_H__
+
+#include <QChartGlobal>
+#include <QGraphicsItem>
+#include <QFont>
+
+QT_BEGIN_NAMESPACE
+class QGraphicsSceneMouseEvent;
+QT_END_NAMESPACE
+
+QT_CHARTS_BEGIN_NAMESPACE
+class QChart;
+QT_CHARTS_END_NAMESPACE
+
+QT_CHARTS_USE_NAMESPACE
+
+class Callout : public QGraphicsItem
+{
+public:
+    Callout(QChart *parent);
+
+    void setText(const QString &text);
+    void setAnchor(QPointF point);
+    void updateGeometry();
+
+    QRectF boundingRect() const;
+    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget);
+
+protected:
+    void mousePressEvent(QGraphicsSceneMouseEvent *event);
+    void mouseMoveEvent(QGraphicsSceneMouseEvent *event);
+
+private:
+    QString text;
+    QRectF textRect;
+    QRectF rect;
+    QPointF anchor;
+    QFont font;
+    QChart *chart;
+};
+
+#endif /* __CALLOUT_H__ */

chartview.cpp

+#include "chartview.h"
+
+ChartView::ChartView(QChart *chart, QWidget *parent) :
+    QChartView(chart, parent),
+    isClicking(false),
+    xOld(0), yOld(0)
+{
+    setRubberBand(QChartView::RectangleRubberBand);
+}
+
+void ChartView::mousePressEvent(QMouseEvent *event)
+{
+    if (event->button() & Qt::LeftButton) {
+        isClicking = true;
+    } else if (event->button() & Qt::RightButton) {
+        chart()->zoomReset();
+    }
+
+    QChartView::mousePressEvent(event);
+}
+
+void ChartView::mouseMoveEvent(QMouseEvent *event)
+{
+    int x, y;
+
+    if (isClicking) {
+        if (xOld == 0 && yOld == 0) {
+
+        } else {
+            x = event->x() - xOld;
+            y = event->y() - yOld;
+            chart()->scroll(-x, y);
+        }
+
+        xOld = event->x();
+        yOld = event->y();
+
+        return;
+    }
+
+    QChartView::mouseMoveEvent(event);
+}
+
+void ChartView::mouseReleaseEvent(QMouseEvent *event)
+{
+    if (isClicking) {
+        xOld = yOld = 0;
+        isClicking = false;
+    }
+
+    /* Disable original right click event */
+    if (!(event->button() & Qt::RightButton)) {
+        QChartView::mouseReleaseEvent(event);
+    }
+}
+
+void ChartView::keyPressEvent(QKeyEvent *event)
+{
+    switch (event->key()) {
+    case Qt::Key_Left:
+        chart()->scroll(-10, 0);
+        break;
+    case Qt::Key_Right:
+        chart()->scroll(10, 0);
+        break;
+    case Qt::Key_Up:
+        chart()->scroll(0, 10);
+        break;
+    case Qt::Key_Down:
+        chart()->scroll(0, -10);
+        break;
+    default:
+        keyPressEvent(event);
+        break;
+    }
+}

chartview.h

+#ifndef __CHARTVIEW_H__
+#define __CHARTVIEW_H__
+
+#include <QChartView>
+#include <QRubberBand>
+
+QT_CHARTS_USE_NAMESPACE
+
+class ChartView : public QChartView
+{
+public:
+    ChartView(QChart *chart, QWidget *parent = 0);
+
+protected:
+    void keyPressEvent(QKeyEvent *event);
+    void mousePressEvent(QMouseEvent *event);
+    void mouseMoveEvent(QMouseEvent *event);
+    void mouseReleaseEvent(QMouseEvent *event);
+
+private:
+    bool isClicking;
+
+    int xOld;
+    int yOld;
+};
+
+#endif /* __CHARTVIEW_H__ */

main.cpp

+#include "mainwidget.h"
+#include <QApplication>
+
+int main(int argc, char *argv[])
+{
+    QApplication a(argc, argv);
+    MainWidget w;
+    w.show();
+
+    return a.exec();
+}

mainwidget.cpp

+#include "mainwidget.h"
+#include "ui_mainwidget.h"
+
+#include <QDebug>
+#include <QSerialPort>
+#include <QSerialPortInfo>
+#include <QtMath>
+
+
+MainWidget::MainWidget(QWidget *parent) :
+    QWidget(parent),
+    ui(new Ui::MainWidget),
+    chart(new QChart),
+    tip(0),
+    timer(new QTimer),
+    count(0),
+    isStopping(false)
+{
+    ui->setupUi(this);
+
+    initUI();
+
+    timer->setInterval(50);
+    timer->start();
+
+    initSlot();
+}
+
+MainWidget::~MainWidget()
+{
+    delete ui;
+}
+
+void MainWidget::wheelEvent(QWheelEvent *event)
+{
+    if (event->delta() > 0) {
+        chart->zoom(1.1);
+    } else {
+        chart->zoom(10.0/11);
+    }
+
+    QWidget::wheelEvent(event);
+}
+
+void MainWidget::initUI()
+{
+    ui->comboBox->addItem("TCP");
+    ui->comboBox->addItem("UDP");
+
+    auto ports = QSerialPortInfo::availablePorts();
+    for (auto port : ports) {
+        ui->comboBox->addItem(port.portName());
+    }
+
+    initChart();
+}
+
+void MainWidget::initChart()
+{
+    series = new QLineSeries;
+
+    chart->addSeries(series);
+
+//    series->setUseOpenGL(true);
+
+    chart->createDefaultAxes();
+    chart->axisY()->setRange(-10, 10);
+    chart->axisX()->setRange(0, 96);
+
+    chart->axisX()->setTitleFont(QFont("Microsoft YaHei", 10, QFont::Normal, true));
+    chart->axisY()->setTitleFont(QFont("Microsoft YaHei", 10, QFont::Normal, true));
+    chart->axisX()->setTitleText("Time/sec");
+    chart->axisY()->setTitleText("Speed/m");
+
+    chart->axisX()->setGridLineVisible(false);
+    chart->axisY()->setGridLineVisible(false);
+
+    /* hide legend */
+    chart->legend()->hide();
+
+    chartView = new ChartView(chart);
+    chartView->setRenderHint(QPainter::Antialiasing);
+
+    ui->mainHorLayout->addWidget(chartView);
+}
+
+void MainWidget::initSlot()
+{
+    connect(timer, SIGNAL(timeout()), this, SLOT(timerSlot()));
+    connect(ui->stopBtn, SIGNAL(clicked(bool)), this, SLOT(buttonSlot()));
+    connect(series, SIGNAL(hovered(QPointF, bool)), this, SLOT(tipSlot(QPointF,bool)));
+}
+
+void MainWidget::updateData()
+{
+    int i;
+    QVector<QPointF> oldData = series->pointsVector();
+    QVector<QPointF> data;
+
+    if (oldData.size() < 97) {
+        data = series->pointsVector();
+    } else {
+        /* 添加之前老的数据到新的vector中，不复制最前的数据，即每次替换前面的数据
+         * 由于这里每次只添加1个数据，所以为1，使用时根据实际情况修改
+         */
+        for (i = 1; i < oldData.size(); ++i) {
+            data.append(QPointF(i - 1 , oldData.at(i).y()));
+        }
+    }
+
+    qint64 size = data.size();
+    /* 这里表示插入新的数据，因为每次只插入1个，这里为i < 1,
+     * 但为了后面方便插入多个数据，先这样写
+     */
+    for(i = 0; i < 1; ++i){
+        data.append(QPointF(i + size, 10 * sin(M_PI * count * 4 / 180)));
+    }
+
+    series->replace(data);
+
+    count++;
+}
+
+void MainWidget::timerSlot()
+{
+    if (QObject::sender() == timer) {
+        updateData();
+    }
+}
+
+void MainWidget::buttonSlot()
+{
+    if (QObject::sender() == ui->stopBtn) {
+        if (!isStopping) {
+            timer->stop();
+        } else {
+            timer->start();
+        }
+        isStopping = !isStopping;
+    }
+}
+
+void MainWidget::tipSlot(QPointF position, bool isHovering)
+{
+    if (tip == 0)
+        tip = new Callout(chart);
+
+    if (isHovering) {
+        tip->setText(QString("X: %1 \nY: %2 ").arg(position.x()).arg(position.y()));
+        tip->setAnchor(position);
+        tip->setZValue(11);
+        tip->updateGeometry();
+        tip->show();
+    } else {
+        tip->hide();
+    }
+}
+

mainwidget.h

+#ifndef MAINWIDGET_H
+#define MAINWIDGET_H
+
+#include <QWidget>
+#include <QChart>
+#include <QLineSeries>
+#include <QVector>
+#include <QTimer>
+
+#include "chartview.h"
+#include "callout.h"
+
+QT_CHARTS_USE_NAMESPACE
+
+namespace Ui {
+class MainWidget;
+}
+
+class MainWidget : public QWidget
+{
+    Q_OBJECT
+
+public:
+    explicit MainWidget(QWidget *parent = 0);
+    ~MainWidget();
+
+private:
+    void wheelEvent(QWheelEvent *event);
+
+    void initUI();
+    void initChart();
+    void initSlot();
+
+    void updateData();
+
+    Ui::MainWidget *ui;
+
+    ChartView *chartView;
+    QChart *chart;
+    Callout *tip;
+    QLineSeries *series;
+
+    QTimer *timer;
+
+    quint16 count;
+
+    bool isStopping;
+
+private slots:
+    void timerSlot();
+    void buttonSlot();
+    void tipSlot(QPointF position, bool isHovering);
+
+};
+
+#endif // MAINWIDGET_H

mainwidget.ui

+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>MainWidget</class>
+ <widget class="QWidget" name="MainWidget">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>800</width>
+    <height>640</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>MainWidget</string>
+  </property>
+  <layout class="QGridLayout" name="gridLayout">
+   <item row="1" column="0">
+    <layout class="QVBoxLayout" name="mainVerLayout">
+     <item>
+      <layout class="QHBoxLayout" name="horizontalLayout_2">
+       <item>
+        <layout class="QHBoxLayout" name="mainHorLayout"/>
+       </item>
+      </layout>
+     </item>
+     <item>
+      <layout class="QHBoxLayout" name="horizontalLayout">
+       <item>
+        <widget class="QLabel" name="label">
+         <property name="text">
+          <string>输入源：</string>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <widget class="QComboBox" name="comboBox"/>
+       </item>
+       <item>
+        <spacer name="horizontalSpacer">
+         <property name="orientation">
+          <enum>Qt::Horizontal</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>40</width>
+           <height>20</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+       <item>
+        <widget class="QPushButton" name="stopBtn">
+         <property name="text">
+          <string>停止</string>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <spacer name="horizontalSpacer_2">
+         <property name="orientation">
+          <enum>Qt::Horizontal</enum>
+         </property>
+         <property name="sizeHint" stdset="0">
+          <size>
+           <width>40</width>
+           <height>20</height>
+          </size>
+         </property>
+        </spacer>
+       </item>
+       <item>
+        <widget class="QPushButton" name="settingBtn">
+         <property name="text">
+          <string>设置</string>
+         </property>
+        </widget>
+       </item>
+      </layout>
+     </item>
+    </layout>
+   </item>
+  </layout>
+ </widget>
+ <layoutdefault spacing="6" margin="11"/>
+ <resources/>
+ <connections/>
+</ui>