相关资料：
https://blog.csdn.net/weixin_30608131/article/details/95468028?utm_medium=distribute.pc_relevant.none-task-blog-searchFromBaidu-1.control&depth_1-utm_source=distribute.pc_relevant.none-task-blog-searchFromBaidu-1.control
mainwindow.cpp
1 #include "mainwindow.h" 2 #include "ui_mainwindow.h" 3 4 MainWindow::MainWindow(QWidget *parent) 5 : QMainWindow(parent) 6 , ui(new Ui::MainWindow) 7 { 8 ui->setupUi(this); 9 10 // 设置垂直滚动条基本样式 11 ui->scrollArea->setStyleSheet("QScrollBar:vertical" 12 "{" 13 "8px;" 14 "background:rgba(255,0,0,0%);" 15 "margin:0px,0px,0px,0px;" 16 // "padding-top:9px;"// 留出9px给上面和下面的箭头 17 // "padding-bottom:9px;" 18 "}" 19 "QScrollBar::handle:vertical" 20 "{" 21 "8px;" 22 "background:rgba(255,0,0,25%);" 23 " border-radius:4px;"// 滚动条两端变成椭圆 24 "min-height:20;" 25 "}" 26 "QScrollBar::handle:vertical:hover" 27 "{" 28 "8px;" 29 "background:rgba(255,0,0,50%);"// 鼠标放到滚动条上的时候，颜色变深 30 " border-radius:4px;" 31 "min-height:20;" 32 "}" 33 "QScrollBar::add-line:vertical" 34 "{" 35 "height:9px;8px;" 36 "border-image:url(:/images/a/3.png);"// 这个应该是设置下箭头的，3.png就是箭头 37 "subcontrol-position:bottom;" 38 "}" 39 "QScrollBar::sub-line:vertical" 40 "{" 41 "height:9px;8px;" 42 "border-image:url(:/images/a/1.png);" // 设置上箭头 43 "subcontrol-position:top;" 44 "}" 45 "QScrollBar::add-line:vertical:hover" 46 "{" 47 "height:9px;8px;" 48 "border-image:url(:/images/a/4.png);"// 当鼠标放到下箭头上的时候 49 "subcontrol-position:bottom;" 50 "}" 51 "QScrollBar::sub-line:vertical:hover" 52 "{" 53 "height:9px;8px;" 54 "border-image:url(:/images/a/2.png);"// 当鼠标放到下箭头上的时候 55 "subcontrol-position:top;" 56 "}" 57 "QScrollBar::add-page:vertical,QScrollBar::sub-page:vertical"// 当滚动条滚动的时候，上面的部分和下面的部分 58 "{" 59 "background:rgba(255,0,0,10%);" 60 "border-radius:4px;" 61 "}" 62 ); 63 } 64 65 MainWindow::~MainWindow() 66 { 67 delete ui; 68 }