ffmpeg播放器实战（视频播放ui）

Display::Display(QWidget*parent)
    : QWidget{parent}
{
mWidth=16;
mHeight=9;
mVideo=newQWidget(this);
//使用setAutoFillBackground函数可以启用或禁用自动填充背景的功能mVideo->setAutoFillBackground(true);
//Qt::WA_StyledBackground是一个用于启用QWidget的样式背景的属性mVideo->setAttribute(Qt::WA_StyledBackground);
mVideo->setStyleSheet("background-color: black;");
this->setAutoFillBackground(true);
this->setAttribute(Qt::WA_StyledBackground);
this->setStyleSheet("background-color: black;");
}
Display::~Display()
{
deletemVideo;
}

voidDisplay::resizeEvent(QResizeEvent*event)
{
setWidgetSize();
QWidget::resizeEvent(event);
}
voidDisplay::setWidgetSize()
{
intwidgetWidth=this->width();
intwidgetHeight=this->height();
/**   宽比     宽度*   ——   =  ——*   高比     高度**  根据宽度得到高度**  如果得到高度大于实际高度**  则：**  根据高度得到宽度**/inttempWidth=widgetWidth;
inttempHeight=tempWidth*this->mHeight/this->mWidth;
if (tempHeight>widgetHeight) {
tempHeight=widgetHeight;
tempWidth=tempHeight*this->mWidth/this->mHeight;
    }
//如果计算出来在波动范围内则不动if (tempWidth>=widgetWidth-1&&tempWidth<=widgetWidth+1&&tempHeight>=widgetHeight-1&&tempHeight<=widgetHeight+1)
return;
mVideo->setGeometry((widgetWidth-tempWidth) /2, (widgetHeight-tempHeight) /2, tempWidth, tempHeight);
}
voidDisplay::setNewSize(intwidth, intheight)
{
mWidth=width;
mHeight=height;
setWidgetSize();
}
QWidget*Display::getVideo()
{
returnmVideo;
}