Qt客户端技巧 -- 窗口美化 -- 圆角窗口

不解析，直接给代码例子

利用窗口重绘事件处理函数paintEvent

main.cpp

#include 
#if QT_VERSION >= 0x050000
#include 
#else
#include 
#endif

#include "roundedwindow.h"

int main(int argc, char *argv[]) {
  QApplication a(argc, argv);

  RoundedWindow wnd{};
  wnd.init();

  return a.exec();
}

roundedwindow.h

#ifndef ROUNDEDWINDOW_H
#define ROUNDEDWINDOW_H

#include 
#if QT_VERSION >= 0x050000
#include 
#else
#include 
#endif

class RoundedWindow : public QWidget {
  Q_OBJECT
public:
  explicit RoundedWindow(QWidget *parent = nullptr);

  void init();

protected:
  void paintEvent(QPaintEvent *event) override;

signals:
};

#endif // ROUNDEDWINDOW_H

roundedwindow.cpp

#include "roundedwindow.h"
#include 
#include 
#include 

RoundedWindow::RoundedWindow(QWidget *parent) : QWidget{parent} {

  /* setAttribute 与 setWindowFlag 尽量写在构造函数，写在其他操作之前 */
  // 背景透明
  this->setAttribute(Qt::WA_TranslucentBackground, true);
  // 无边框
  this->setWindowFlag(Qt::FramelessWindowHint);
}

void RoundedWindow::init() {
  this->show();
  QLayout *mainLayout = new QVBoxLayout{this};
  QPushButton *btn = new QPushButton{this};
  btn->setText(QStringLiteral("你好"));
  mainLayout->addWidget(btn);
  this->setLayout(mainLayout);
}

void RoundedWindow::paintEvent(QPaintEvent *event) {
  QPainter painter{this};
  painter.setRenderHint(QPainter::Antialiasing); // 抗据齿,绘图更加平滑
  painter.setBrush(QBrush{QColor{155, 54, 54}});
  painter.drawRoundedRect(this->rect(), 15, 15);
}

利用qss改变主窗口样式

main.cpp

#include 
#if QT_VERSION >= 0x050000
#include 
#else
#include 
#endif

#include "roundedwindow.h"

int main(int argc, char *argv[]) {
  QApplication a(argc, argv);

  RoundedWindow wnd{};
  wnd.init();

  return a.exec();
}

roundedwindow.h

#ifndef ROUNDEDWINDOW_H
#define ROUNDEDWINDOW_H

#include 
#if QT_VERSION >= 0x050000
#include 
#else
#include 
#endif

class RoundedWindow : public QWidget {
  Q_OBJECT
public:
  explicit RoundedWindow(QWidget *parent = nullptr);

  void init();

protected:
  void paintEvent(QPaintEvent *event) override;

signals:
};

#endif // ROUNDEDWINDOW_H

roundedwindow.cpp

#include "roundedwindow.h"
#include 
#include 
#include 
#include 

RoundedWindow::RoundedWindow(QWidget *parent) : QWidget{parent} {

  /* setAttribute 与 setWindowFlag 尽量写在构造函数，写在其他操作之前 */
  // 背景透明
  this->setAttribute(Qt::WA_TranslucentBackground, true);
  // 无边框
  this->setWindowFlag(Qt::FramelessWindowHint);
}

void RoundedWindow::init() {
  this->show();
  this->setStyleSheet("QWidget {"
                      " background-color:gray;"
                      " border-radius:15px;"
                      "}");
}

void RoundedWindow::paintEvent(QPaintEvent *event) {
  Q_UNUSED(event);
  /* qwidget的qss仅支持background、background-clip和background-origin属性。
   * 如果您继承QWidget，则需要为自定义QWidget提供paintEvent，如下所示 */
  QStyleOption opt;
  opt.initFrom(this);
  QPainter p(this);
  style()->drawPrimitive(QStyle::PE_Widget, &opt, &p, this);
}