Qt 窗口(控件)圆角或其他形状

注意: 以下几种方法, 在没有父窗口情况下, 鼠标热点范围和非透明范围一致; 在有父窗口情况下,鼠标热点范围仍然为矩形;  如果想改变鼠标的热点范围,见https://blog.youkuaiyun.com/qq_33259248/article/details/128222959

1.  方法1

   MyWidget::MyWidget(QWidget *parent):
       QWidget(parent)
   {
       setWindowFlags(Qt::FramelessWindowHint);
       setAttribute(Qt::WA_TranslucentBackground);
       setFixedSize(100, 100);
   }
   
   void MyWidget::paintEvent(QPaintEvent *event)
   {
       QPainter p(this);
       p.setRenderHint(QPainter::Antialiasing);
       p.setPen(Qt::NoPen);
       p.setBrush(Qt::red);
       p.drawRoundedRect(this->rect(), 25, 25);
   }
   
   
   

     无父窗口效果, 有父窗口效果
2. 方法2

   MyWidget::MyWidget(QWidget *parent):
       QWidget(parent)
   {
       setWindowFlags(Qt::FramelessWindowHint);
       setAttribute(Qt::WA_TranslucentBackground);
       setFixedSize(100, 100);
       this->setStyleSheet("background-color: #FF0000; border: 0px solid rgba(255,255,255,1);border-radius:25px;}");
   }
   
   void MyWidget::paintEvent(QPaintEvent *event)
   {
       QStyleOption opt;
       opt.initFrom(this);
       QPainter p(this);
       style()->drawPrimitive(QStyle::PE_Widget, &opt, &p, this);
   }
   
   
   

   无父窗口效果, 有父窗口效果

3.  方法3 

   MyWidget::MyWidget(QWidget *parent):
       QWidget(parent)
   {
       setWindowFlags(Qt::FramelessWindowHint);
       setAttribute(Qt::WA_TranslucentBackground);
       setFixedSize(400, 400);
   }
   
   void MyWidget::paintEvent(QPaintEvent *)
   {
       QPainter painter(this);
       painter.setRenderHint(QPainter::Antialiasing);
       QBrush brush(QColor(0, 0, 255), Qt::SolidPattern);
       painter.setBrush(brush);
   
       QPainterPath path;
       path.moveTo(100, 100);
       path.lineTo(130, 100);
       path.lineTo(140, 90);
       path.lineTo(150, 100);
       path.lineTo(200, 100);
       path.arcTo(150, 150, 50, 50,  0.0f,  -90.0f);
       path.lineTo(100, 200);
       path.closeSubpath();
   
       QFont myFont;
       myFont.setPixelSize(12);
       QPointF baseline(120, 120);
       path.addText(baseline, myFont, tr("Qt"));
   
       QPen pen;
       painter.setPen(Qt::NoPen);
       painter.drawPath(path);
   }
   

    无父窗口效果, 有父窗口效果

4. 方法4  只针对按钮 , 根据现有的图片绘制

   :/view/view/doing1.png

   

    

   MyWidget::MyWidget(QWidget *parent):
       QPushButton(parent)
   {
       setWindowFlags(Qt::FramelessWindowHint);
       setAttribute(Qt::WA_TranslucentBackground);
   
       QPixmap aaa(":/view/view/doing1.png");
       setFixedSize(aaa.size());
   
       setStyleSheet(" border-image:url(:/view/view/doing1.png);");
   }
   
   
   
   

      无父窗口效果, 有父窗口效果