From c442a1a41c8d112c18f100321e3e74cf8d28a164 Mon Sep 17 00:00:00 2001 From: Darcy Hu Date: Sat, 21 Apr 2018 09:38:23 +0800 Subject: [PATCH] Simple example drawing a sine curve and a line with Qt Charts. --- SineCurve.pro | 35 +++++++++++++++++++++++ main.cpp | 11 ++++++++ mainwindow.cpp | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++ mainwindow.h | 32 +++++++++++++++++++++ mainwindow.ui | 66 +++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 221 insertions(+) create mode 100644 SineCurve.pro create mode 100644 main.cpp create mode 100644 mainwindow.cpp create mode 100644 mainwindow.h create mode 100644 mainwindow.ui diff --git a/SineCurve.pro b/SineCurve.pro new file mode 100644 index 0000000..e0b1b5c --- /dev/null +++ b/SineCurve.pro @@ -0,0 +1,35 @@ +#------------------------------------------------- +# +# Project created by QtCreator 2018-04-19T23:02:45 +# +#------------------------------------------------- + +# 记得加上 charts 模块 +QT += core gui charts + +greaterThan(QT_MAJOR_VERSION, 4): QT += widgets + +TARGET = SineCurve +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 \ + mainwindow.cpp + +HEADERS += \ + mainwindow.h + +FORMS += \ + mainwindow.ui diff --git a/main.cpp b/main.cpp new file mode 100644 index 0000000..b48f94e --- /dev/null +++ b/main.cpp @@ -0,0 +1,11 @@ +#include "mainwindow.h" +#include + +int main(int argc, char *argv[]) +{ + QApplication a(argc, argv); + MainWindow w; + w.show(); + + return a.exec(); +} diff --git a/mainwindow.cpp b/mainwindow.cpp new file mode 100644 index 0000000..3cd343e --- /dev/null +++ b/mainwindow.cpp @@ -0,0 +1,77 @@ +#include "mainwindow.h" +#include "ui_mainwindow.h" + +MainWindow::MainWindow(QWidget *parent) : + QMainWindow(parent), + ui(new Ui::MainWindow) +{ + ui->setupUi(this); +} + +MainWindow::~MainWindow() +{ + delete ui; +} + +void MainWindow::on_actionDraw_triggered() +{ + // 用于绘制 spline chart 的数据 + QSplineSeries *sp = new QSplineSeries(); + + // 添加数据到 sp 中，这里取 y = sin(x), -pi < x < pi + for (double x = -M_PI; x < M_PI; x += 0.01) { + sp->append(x, sin(x)); + } + + // 用于绘制 line chart 的数据 + QLineSeries *line = new QLineSeries(); + // 添加数据 line 中，这里取 y = x^2 - 1, -3 < x < 3 + // 这里取步长为 0.5，这样可以方便看出来 line chart 和 spline chart 的区别 + for(double x = -3; x < 3; x += 0.5) + { + line->append(x, x*x - 1); + } + + // 设置名称，会在图例中显示 + sp->setName(tr("y = sin(x)")); + line->setName(tr("y = x^2 - 1")); + // 使用 openGL 渲染，可以提速，但是对于这个简单的例子是没有什么区别的 + sp->setUseOpenGL(true); + + // QChart 类用于管理图表中各种元素，包括坐标点，风格，坐标轴和图例等，这个用于笛卡尔坐标 + // 另外有 QPolarChart 用于极坐标 + QChart *chart = new QChart(); + + // 将 series 添加到图表中，可以添加多个 + chart->addSeries(sp); + chart->addSeries(line); + + // 绘制默认的坐标轴 + chart->createDefaultAxes(); + + // 设置图表的标题 + chart->setTitle(tr("简单的 Qt Charts 例子")); + + // 设置 x 轴的范围 + chart->axisX()->setRange(-4, 4); + // 设置 y 轴的范围 + chart->axisY()->setRange(-1.2, 1.2); + + // 设置图表的主题，取值为枚举 QChart::ChartTheme + chart->setTheme(QChart::ChartThemeBlueIcy); + + // 设置动画效果，取值为枚举 QChart::AnimationOption + chart->setAnimationOptions(QChart::AllAnimations); + chart->legend()->setAlignment(Qt::AlignBottom); + //chart->legend()->setVisible(true); + + // QChartView 是一个独立的 Qt widget，用来显示 QChart 的． + // 这里 chartView 是界面里的一个 widget，它是从 Qt Widget 提升为 QChartView 得到的 + // Qt Creator 并没有单独的一个 widget 叫做 QChartView + // **关键** 这里要用 setChart 方法将 chart 作为显示的图表 + // 这一句是将界面中的 QChartView 跟 QChart 联系起来的关键 + ui->chartView->setChart(chart); + + // 打开抗锯齿，提升显示效果 + ui->chartView->setRenderHint(QPainter::Antialiasing); +} diff --git a/mainwindow.h b/mainwindow.h new file mode 100644 index 0000000..55214c9 --- /dev/null +++ b/mainwindow.h @@ -0,0 +1,32 @@ +#ifndef MAINWINDOW_H +#define MAINWINDOW_H + +#include +// 包含 QtCharts，ui 文件是不能直接编辑的，ui 文件生成的代码会用到 QtCharts +// 而 mainwindow 对应的 ui 文件生成的代码会包含头文件 mainwindow.h +// 因此可以将 QtCharts 的头文件包含写在这里 +#include +// 下面两句是等价的 +// using namespace QtCharts +QT_CHARTS_USE_NAMESPACE + +namespace Ui { +class MainWindow; +} + +class MainWindow : public QMainWindow +{ + Q_OBJECT + +public: + explicit MainWindow(QWidget *parent = 0); + ~MainWindow(); + +private slots: + void on_actionDraw_triggered(); + +private: + Ui::MainWindow *ui; +}; + +#endif // MAINWINDOW_H diff --git a/mainwindow.ui b/mainwindow.ui new file mode 100644 index 0000000..9e7be74 --- /dev/null +++ b/mainwindow.ui @@ -0,0 +1,66 @@ + + + MainWindow + + + + 0 + 0 + 400 + 300 + + + + MainWindow + + + + + + + + + + + + 0 + 0 + 400 + 29 + + + + + &File + + + + + + + + TopToolBarArea + + + false + + + + + + Draw + + + + + + + QChartView + QWidget +
QtCharts/QChartView
+ 1 + + + + +