Qt 自定义 转盘 控件[纯代码]
一 结果图示
二 头文件
#ifndef DASHBOARD_H
#define DASHBOARD_H
#include <QWidget>
#include <QPainter>
#include <QtMath>
#include <QDebug>
class DashBoard : public QWidget
{
Q_OBJECT
public:
explicit DashBoard(QWidget *parent = nullptr);
~DashBoard();
void setRange(double minValue, double maxValue); //设置刻度范围
void setValue(double value); //设置值
void setValue(int value); //设置值
void setPrecision(int precision); //设置精确度，小数点后几位
void setScaleMajor(int scaleMajor); //设置大刻度数量
void setScaleMinor(int scaleMinor); //设置小刻度数量
void setOuterCircleColor(const QColor &outerCircleColor); //设置外圆背景颜色
void setInnerCircleColor(const QColor &innerCircleColor); //设置内圆背景颜色
void setPieColor(const QColor &pieColor); //设置当前值扇形的颜色
void setScaleColor(const QColor &scaleColor); //设置刻度尺颜色
void setPointerColor(const QColor &pointerColor); //设置指针颜色
void setTextColor(const QColor &textColor); //设置文本颜色
void setShowOverlay(bool showOverlay); //设置是否显示外罩层
void setOverlayColor(const QColor &overlayColor); //设置外罩层颜色
protected:
void paintEvent(QPaintEvent *); //绘制事件重写
void drawOuterCircle(QPainter *painter); //画外圆
void drawInnerCircle(QPainter *painter); //画内圆
void drawScale(QPainter *painter); //画刻度
void drawScaleNum(QPainter *painter); //画刻度值
void drawOverlay(QPainter *painter); //画外罩
void drawValuePie(QPainter *painter); //画扇形值
void drawPointerTriangle(QPainter *painter); //画三角指针
void drawValue(QPainter *painter); //画值
private:
QColor m_outerCircleColor; //外圆背景颜色
QColor m_innerCircleColor; //内圆背景颜色
QColor m_scaleColor; //刻度值颜色
QColor m_pieColorValue; //当前值颜色
QColor m_pointerColor; //指针颜色
QColor m_overlayColor; //遮罩层颜色
QColor m_textColor; //文本颜色
double m_minValue = 0; //最小值
double m_maxValue = 100; //最大值
double m_value = 0; //当前值
int m_precision = 0; //精确度,小数点后几位
int m_startAngle = 0; //开始旋转角度
int m_endAngle = 0; //结束旋转角度
int m_scaleMajor = 10; //大刻度数量
int m_scaleMinor = 10; //小刻度数量
bool m_showOverlay = true; //显示遮罩层
};
#endif // DASHBOARD_H
三 源代码
#include "dashboard.h"
DashBoard::DashBoard(QWidget *parent) : QWidget(parent)
{
m_outerCircleColor = QColor(210, 210, 210);
m_innerCircleColor = QColor(255, 255, 255);
m_scaleColor = QColor(56, 119, 246);
m_overlayColor = QColor(217, 100, 255);
m_pieColorValue = QColor(56, 119, 246);
m_pointerColor = QColor(255, 0, 0);
m_textColor = QColor(12, 29, 62);
}
DashBoard::~DashBoard()
{
}
//重写绘制事件
void DashBoard::paintEvent(QPaintEvent *)
{
int width = this->width();
int height = this->height();
int side = qMin(width, height);
QPainter painter(this);
painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);//设置给定的渲染提示;
painter.translate(width / 2, height / 2);//平移
painter.scale(side / 200.0, side / 200.0);//将坐标系缩放
drawOuterCircle(&painter); //画外圆
drawScale(&painter); //画刻度
drawScaleNum(&painter); //画刻度值
drawOverlay(&painter); //画外罩
drawValuePie(&painter); //画扇形
drawInnerCircle(&painter); //画内圆 遮住扇形一部分 成饼形
drawPointerTriangle(&painter); //画指针
drawValue(&painter); //画值
}
//外圆
void DashBoard::drawOuterCircle(QPainter *painter)
{
int radius = 65;
painter->save();
painter->setPen(Qt::NoPen);
painter->setBrush(m_outerCircleColor);
painter->drawEllipse(-radius, -radius, radius * 2, radius * 2);
painter->restore();
}
//内圆
void DashBoard::drawInnerCircle(QPainter *painter)
{
int radius = 50;
painter->save();
painter->setPen(Qt::NoPen);
painter->setBrush(m_innerCircleColor);
painter->drawEllipse(-radius, -radius, radius * 2, radius * 2);
painter->restore();
}
//画刻度
void DashBoard::drawScale(QPainter *painter)
{
int radius = 80;
painter->save();
painter->rotate(m_startAngle);
int steps = (m_scaleMajor * m_scaleMinor);
double angleStep = (360.0 - m_startAngle - m_endAngle) / steps;
QPen pen;
pen.setColor(m_scaleColor);
pen.setCapStyle(Qt::RoundCap);
for (int i = 0; i <= steps; i++) {
if (i % m_scaleMinor == 0) {
pen.setWidthF(1.5);
painter->setPen(pen);
painter->drawLine(0, radius - 10, 0, radius);
} else {
pen.setWidthF(0.5);
painter->setPen(pen);
painter->drawLine(0, radius - 10, 0, radius-5);
}
painter->rotate(angleStep);
}
painter->restore();
}
//画刻度值
void DashBoard::drawScaleNum(QPainter *painter)
{
int radius = 90;
painter->save();
painter->setPen(m_scaleColor);
double startRad = (360 - m_startAngle - 90) * (M_PI / 180);
double deltaRad = (360 - m_startAngle - m_endAngle) * (M_PI / 180) / m_scaleMajor;
for (int i = 0; i < m_scaleMajor; i++)
{
double sina = qSin(startRad - i * deltaRad);
double cosa = qCos(startRad - i * deltaRad);
double value = 1.0 * i * ((m_maxValue - m_minValue) / m_scaleMajor) + m_minValue;
//QString strValue = QString("%1").arg((double)value, 0, 'f', m_precision);
QString strValue = QString("%1").arg(static_cast<double>(value), 0, 'f', 0);
double textWidth = fontMetrics().width(strValue);
double textHeight = fontMetrics().height();
int x = static_cast<int>(radius * cosa - textWidth / 2);
int y = static_cast<int>(-radius * sina + textHeight / 4);
painter->drawText(x, y, strValue);
}
painter->restore();
}
//画外罩
void DashBoard::drawOverlay(QPainter *painter)
{
if (!m_showOverlay) {
return;
}
int radius = 100;
painter->save();
painter->setPen(Qt::NoPen);
QPainterPath smallCircle;
QPainterPath bigCircle;
radius -= 1;
smallCircle.addEllipse(-radius, -radius, radius * 2, radius * 2);
radius *= 2;
bigCircle.addEllipse(-radius, -radius + 140, radius * 2, radius * 2);
//高光的形状为小圆扣掉大圆的部分
QPainterPath highlight = smallCircle - bigCircle;
QLinearGradient linearGradient(0, -radius / 2, 0, 0);
m_overlayColor.setAlpha(100);
linearGradient.setColorAt(0.0, m_overlayColor);
m_overlayColor.setAlpha(30);
linearGradient.setColorAt(1.0, m_overlayColor);
painter->setBrush(linearGradient);
painter->rotate(-20);
painter->drawPath(smallCircle);
painter->restore();
}
//画扇形
void DashBoard::drawValuePie(QPainter *painter)
{
int radius = 65;
painter->save();
painter->setPen(Qt::NoPen);
QRectF rect(-radius, -radius, radius * 2, radius * 2);
double angle = (m_value / m_maxValue) * 360;
//绘制开始饼圆
painter->setBrush(m_pieColorValue);
painter->drawPie(rect, -90 * 16, static_cast<int>(-angle * 16));//三点钟为0点
painter->restore();
}
//指针
void DashBoard::drawPointerTriangle(QPainter *painter)
{
int radius = 10;
int offset = 39;
painter->save();
painter->setPen(Qt::NoPen);
painter->setBrush(m_pointerColor);
QPolygon pts;
pts.setPoints(3, -5, 0 + offset, 5, 0 + offset, 0, radius + offset);
painter->rotate(m_startAngle);
double degRotate = (360.0 - m_startAngle - m_endAngle) / (m_maxValue - m_minValue) * (m_value - m_minValue);
painter->rotate(degRotate);
painter->drawConvexPolygon(pts);
painter->restore();
}
//画文本
void DashBoard::drawValue(QPainter *painter)
{
int radius = 100;
painter->save();
painter->setPen(m_textColor);
QFont font;
font.setPixelSize(24);
painter->setFont(font);
QRectF textRect(-radius, -radius, radius * 2, radius * 2);
QString strValue = QString("%1um").arg((double)m_value, 0, 'f', m_precision);
painter->drawText(textRect, Qt::AlignCenter, strValue);
painter->restore();
}
//设置刻度范围
void DashBoard::setRange(double minValue, double maxValue)
{
m_minValue = minValue;
m_maxValue = maxValue;
update();
}
//设置值
void DashBoard::setValue(double value)
{
m_value = value;
update();
}
//设置值
void DashBoard::setValue(int value)
{
m_value = value;
update();
}
//设置精确度
void DashBoard::setPrecision(int precision)
{
m_precision = precision;
update();
}
//设置大刻度数量
void DashBoard::setScaleMajor(int scaleMajor)
{
m_scaleMajor = scaleMajor;
update();
}
//设置小刻度数量
void DashBoard::setScaleMinor(int scaleMinor)
{
m_scaleMinor = scaleMinor;
update();
}
//设置外圆颜色
void DashBoard::setOuterCircleColor(const QColor &outerCircleColor)
{
m_outerCircleColor = outerCircleColor;
update();
}
//设置内圆颜色
void DashBoard::setInnerCircleColor(const QColor &innerCircleColor)
{
m_innerCircleColor = innerCircleColor;
update();
}
//设置饼形颜色
void DashBoard::setPieColor(const QColor &pieColor)
{
m_pieColorValue = pieColor;
update();
}
//设置刻度尺颜色
void DashBoard::setScaleColor(const QColor &scaleColor)
{
m_scaleColor = scaleColor;
update();
}
//设置指针颜色
void DashBoard::setPointerColor(const QColor &pointerColor)
{
m_pointerColor = pointerColor;
update();
}
//设置文本颜色
void DashBoard::setTextColor(const QColor &textColor)
{
m_textColor = textColor;
update();
}
//设置是否显示外罩
void DashBoard::setShowOverlay(bool showOverlay)
{
m_showOverlay = showOverlay;
update();
}
