本节对应的视频讲解：B_站_视_频

https://www.bilibili.com/video/BV1qd4y1s7xk

布局完成后，就可以修改控件的名称，以及添加初始化数据

1. 变量命名

先修改各控件显示的的名称，做到 “见名知义”，方便写代码

修改完控件名称后的效果如下：

2. 初始化数据

为各个控件添加初始化数据

2.1 形状

为 cboShape 控件，添加形状

首先，在 paintwidget.h 中定义一个枚举类型，表示形状的类型，如下：

enum Shape {_Point,         //_Line,          //_Rect,          //_RoundedRect,   //_Ellipse,       //_Polyline,      //_Polygon,       //_Arc,           //_Pie,           //_Chord,         //_Path,          //_Text,          //_Pixmap
};

然后，在 widget.cpp 的构造中，添加如下初始化代码：

Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);// 1. 形状ui->cboShape->addItem("Point", static_cast(_Point));ui->cboShape->addItem("Line", static_cast(_Line));ui->cboShape->addItem("Rectangle", static_cast(_Rect));ui->cboShape->addItem("Rounded Rectangle", static_cast(_RoundedRect));ui->cboShape->addItem("Ellipse", static_cast(_Ellipse));ui->cboShape->addItem("Arc", static_cast(_Arc));ui->cboShape->addItem("Pie", static_cast(_Pie));ui->cboShape->addItem("Chord", static_cast(_Chord));ui->cboShape->addItem("Polyline", static_cast(_Polyline));ui->cboShape->addItem("Polygon", static_cast(_Polygon));ui->cboShape->addItem("Path", static_cast(_Path));ui->cboShape->addItem("Text", static_cast(_Text));ui->cboShape->addItem("Pixmap", static_cast(_Pixmap));
}

2.2 画笔

初始化画笔的属性

Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);// 2. 线宽ui->sbPenWidth->setRange(1, 10);// 3. 线型// 3.1 线型-实线、虚线、点画线等ui->cboPenStyle->addItem("Solid", static_cast(Qt::SolidLine));ui->cboPenStyle->addItem("Dash", static_cast(Qt::DashLine));ui->cboPenStyle->addItem("Dot", static_cast(Qt::DotLine));ui->cboPenStyle->addItem("Dash Dot", static_cast(Qt::DashDotLine));ui->cboPenStyle->addItem("Dash Dot Dot", static_cast(Qt::DashDotDotLine));ui->cboPenStyle->addItem("None", static_cast(Qt::NoPen));// 3.2 线型-线的端点的样式ui->cboPenCap->addItem("Flat", static_cast(Qt::FlatCap));ui->cboPenCap->addItem("Square", static_cast(Qt::SquareCap));ui->cboPenCap->addItem("Round", static_cast(Qt::RoundCap));// 3.3 连接-两根线的连接处的样式ui->cboPenJoin->addItem("Miter", static_cast(Qt::MiterJoin));ui->cboPenJoin->addItem("Bevel", static_cast(Qt::BevelJoin));ui->cboPenJoin->addItem("Round", static_cast(Qt::RoundJoin));
}

2.3 画刷

初始化画刷的属性

Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);// 4. 画刷ui->cboBrushStyle->addItem(tr("Linear Gradient"), static_cast(Qt::LinearGradientPattern));ui->cboBrushStyle->addItem(tr("Radial Gradient"), static_cast(Qt::RadialGradientPattern));ui->cboBrushStyle->addItem(tr("Conical Gradient"), static_cast(Qt::ConicalGradientPattern));ui->cboBrushStyle->addItem(tr("Texture"), static_cast(Qt::TexturePattern));ui->cboBrushStyle->addItem(tr("Solid"), static_cast(Qt::SolidPattern));ui->cboBrushStyle->addItem(tr("Horizontal"), static_cast(Qt::HorPattern));ui->cboBrushStyle->addItem(tr("Vertical"), static_cast(Qt::VerPattern));ui->cboBrushStyle->addItem(tr("Cross"), static_cast(Qt::CrossPattern));ui->cboBrushStyle->addItem(tr("Backward Diagonal"), static_cast(Qt::BDiagPattern));ui->cboBrushStyle->addItem(tr("Forward Diagonal"), static_cast(Qt::FDiagPattern));ui->cboBrushStyle->addItem(tr("Diagonal Cross"), static_cast(Qt::DiagCrossPattern));ui->cboBrushStyle->addItem(tr("Dense 1"), static_cast(Qt::Dense1Pattern));ui->cboBrushStyle->addItem(tr("Dense 2"), static_cast(Qt::Dense2Pattern));ui->cboBrushStyle->addItem(tr("Dense 3"), static_cast(Qt::Dense3Pattern));ui->cboBrushStyle->addItem(tr("Dense 4"), static_cast(Qt::Dense4Pattern));ui->cboBrushStyle->addItem(tr("Dense 5"), static_cast(Qt::Dense5Pattern));ui->cboBrushStyle->addItem(tr("Dense 6"), static_cast(Qt::Dense6Pattern));ui->cboBrushStyle->addItem(tr("Dense 7"), static_cast(Qt::Dense7Pattern));ui->cboBrushStyle->addItem(tr("None"), static_cast(Qt::NoBrush));
}