[提问]关于rotate旋转函数的 [复制链接]

我想实现按一个按钮后让一幅图片转起来。
我先用  void Dialog::paintEvent(QPaintEvent *event)  事件的方法加入一张图片。
之后想用 void Dialog::on_startBtn_clicked()  为点击后的响应事件。
但是总是出现
QPainter::begin: Paint device returned engine == 0, type: 1

QPainter::translate: Painter not active
QPainter::rotate: Painter not active
QPainter::translate: Painter not active
QPainter::begin: Paint device returned engine == 0, type: 1
QPainter::translate: Painter not active
QPainter::rotate: Painter not active
QPainter::translate: Painter not active
QPaintDevice: Cannot destroy paint device that is being painted


请问是怎么回事？
或者有什么其他方法可以实现让它转起来？

已解决

引用楼主a2263667于2011-05-01 03:17发表的 关于rotate旋转函数的 :
我想实现按一个按钮后让一幅图片转起来。
我先用  void Dialog::paintEvent(QPaintEvent *event)  事件的方法加入一张图片。
之后想用 void Dialog::on_startBtn_clicked()  为点击后的响应事件。
但是总是出现
QPainter::begin: Paint device returned engine == 0, type: 1
.......

看下这个帮助文档
Warning: When the paintdevice is a widget, QPainter can only be used inside a paintEvent() function or in a function called by paintEvent(); that is unless the Qt::WA_PaintOutsidePaintEvent widget attribute is set. On Mac OS X and Windows, you can only paint in a paintEvent() function regardless of this attribute's setting.

请问你是怎么解决的？我也遇到了类似的问题

Qt只能在paintEvent();里绘图。