Qt编写自定义控件50-迷你仪表盘 - QTCN开发网

#ifndef GAUGEMINI_H
#define GAUGEMINI_H

/**
* 迷你仪表盘控件作者:feiyangqingyun(QQ:517216493) 2017-11-26
* 1:支持指示器样式选择线条指示器/指针指示器/圆角指针指示器/三角形指示器
* 2:支持鼠标按下旋转改变值
* 3:支持负数刻度值
* 4:支持设置当前值及范围值
* 5:支持左右旋转角度设置
* 6:支持设置刻度数量
* 7:支持设置边框颜色/背景颜色/文本颜色/进度颜色
* 8:支持设置是否等分显示左右值
*/

#include <QWidget>

#ifdef quc
#if (QT_VERSION < QT_VERSION_CHECK(5,7,0))
#include <QtDesigner/QDesignerExportWidget>
#else
#include <QtUiPlugin/QDesignerExportWidget>
#endif

class QDESIGNER_WIDGET_EXPORT GaugeMini : public QWidget
#else
class GaugeMini : public QWidget
#endif

{
    Q_OBJECT
    Q_ENUMS(PointerStyle)

    Q_PROPERTY(double minValue READ getMinValue WRITE setMinValue)
    Q_PROPERTY(double maxValue READ getMaxValue WRITE setMaxValue)
    Q_PROPERTY(double value READ getValue WRITE setValue)
    Q_PROPERTY(int precision READ getPrecision WRITE setPrecision)

    Q_PROPERTY(int step READ getStep WRITE setStep)
    Q_PROPERTY(int startAngle READ getStartAngle WRITE setStartAngle)
    Q_PROPERTY(int endAngle READ getEndAngle WRITE setEndAngle)

    Q_PROPERTY(QColor borderColor READ getBorderColor WRITE setBorderColor)
    Q_PROPERTY(QColor bgColor READ getBgColor WRITE setBgColor)
    Q_PROPERTY(QColor textColor READ getTextColor WRITE setTextColor)
    Q_PROPERTY(QColor percentColor READ getPercentColor WRITE setPercentColor)

    Q_PROPERTY(bool doublePercent READ getDoublePercent WRITE setDoublePercent)
    Q_PROPERTY(bool showValue READ getShowValue WRITE setShowValue)
    Q_PROPERTY(PointerStyle pointerStyle READ getPointerStyle WRITE setPointerStyle)

public:
    enum PointerStyle {
        PointerStyle_Line = 0,          //线条指示器
        PointerStyle_Indicator = 1,     //指针指示器
        PointerStyle_IndicatorR = 2,    //圆角指针指示器
        PointerStyle_Triangle = 3       //三角形指示器
    };

    explicit GaugeMini(QWidget *parent = 0);
    ~GaugeMini();

protected:
    void mousePressEvent(QMouseEvent *);
    void mouseReleaseEvent(QMouseEvent *);
    void mouseMoveEvent(QMouseEvent *);
    void paintEvent(QPaintEvent *);
    void drawScale(QPainter *painter);
    void drawBgCircle(QPainter *painter);
    void drawCenterCircle(QPainter *painter);
    void drawPointerLine(QPainter *painter);
    void drawPointerIndicator(QPainter *painter);
    void drawPointerIndicatorR(QPainter *painter);
    void drawPointerTriangle(QPainter *painter);
    void drawValue(QPainter *painter);

private:
    double minValue;                //最小值
    double maxValue;                //最大值
    double value;                   //目标值
    int precision;                  //精确度,小数点后几位

    int step;                       //刻度数量
    int startAngle;                 //开始旋转角度
    int endAngle;                   //结束旋转角度

    QColor borderColor;             //边框颜色
    QColor bgColor;                 //背景颜色
    QColor textColor;               //文字颜色
    QColor percentColor;            //进度颜色

    bool doublePercent;             //是否对半等分范围值
    bool showValue;                 //是否显示当前值
    PointerStyle pointerStyle;      //指针样式

private:
    //鼠标是否按下
    bool pressed;
    //根据鼠标按下的坐标设置当前按下坐标处的值
    void setPressedValue(QPointF pressedPoint);

public:
    double getMinValue()            const;
    double getMaxValue()            const;
    double getValue()               const;
    int getPrecision()              const;

    int getStep()                   const;
    int getStartAngle()             const;
    int getEndAngle()               const;

    QColor getBorderColor()         const;
    QColor getBgColor()             const;
    QColor getTextColor()           const;
    QColor getPercentColor()        const;

    bool getDoublePercent()         const;
    bool getShowValue()             const;
    PointerStyle getPointerStyle()  const;

    QSize sizeHint()                const;
    QSize minimumSizeHint()         const;

public Q_SLOTS:
    //设置范围值
    void setRange(double minValue, double maxValue);
    void setRange(int minValue, int maxValue);

    //设置最大最小值
    void setMinValue(double minValue);
    void setMaxValue(double maxValue);

    //设置目标值
    void setValue(double value);
    void setValue(int value);

    //设置精确度
    void setPrecision(int precision);

    //设置刻度数量
    void setStep(int step);
    //设置开始旋转角度
    void setStartAngle(int startAngle);
    //设置结束旋转角度
    void setEndAngle(int endAngle);

    //设置边框颜色
    void setBorderColor(const QColor &borderColor);
    //设置背景颜色
    void setBgColor(const QColor &bgColor);
    //设置文本颜色
    void setTextColor(const QColor &textColor);
    //设置进度颜色
    void setPercentColor(const QColor &percentColor);

    //设置是否对半等分范围值
    void setDoublePercent(bool doublePercent);
    //设置是否显示当前值
    void setShowValue(bool showValue);
    //设置指针样式
    void setPointerStyle(const PointerStyle &pointerStyle);

Q_SIGNALS:
    void valueChanged(double value);
};

#endif // GAUGEMINI_H

void GaugeMini::paintEvent(QPaintEvent *)
{
    int width = this->width();
    int height = this->height();
    int side = qMin(width, height);

    //绘制准备工作,启用反锯齿,平移坐标轴中心,等比例缩放
    QPainter painter(this);
    painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);
    painter.translate(width / 2, height / 2);
    painter.scale(side / 200.0, side / 200.0);

    //绘制刻度线
    drawScale(&painter);
    //绘制背景圆
    drawBgCircle(&painter);
    //绘制中心圆
    drawCenterCircle(&painter);

    //根据指示器形状绘制指示器
    if (pointerStyle == PointerStyle_Line) {
        drawPointerLine(&painter);
    } else if (pointerStyle == PointerStyle_Indicator) {
        drawPointerIndicator(&painter);
    } else if (pointerStyle == PointerStyle_IndicatorR) {
        drawPointerIndicatorR(&painter);
    } else if (pointerStyle == PointerStyle_Triangle) {
        drawPointerTriangle(&painter);
    }

    //绘制当前值
    drawValue(&painter);
}

void GaugeMini::drawScale(QPainter *painter)
{
    int radius = 96;
    int offset = 10;
    painter->save();

    painter->rotate(startAngle);
    double angleStep = (360.0 - startAngle - endAngle) / step;
    double degRotate = (360.0 - startAngle - endAngle) / (maxValue - minValue) * (value - minValue);

    QPen pen;
    pen.setWidthF(5.0);
    pen.setCapStyle(Qt::RoundCap);

    double rotate = 0;
    for (int i = 0; i <= step; i++) {
        if (doublePercent) {
            bool right = i >= (step / 2);
            if (!right) {
                pen.setColor((rotate < degRotate) ? textColor : percentColor);
            } else {
                pen.setColor((rotate <= degRotate) ? percentColor : textColor);
            }

            //矫正左侧值为最小值时第一格颜色
            if (value == minValue && !right) {
                pen.setColor(percentColor);
            }

            //矫正左侧值时中间格颜色
            if (value <= ((maxValue - minValue) / 2 + minValue) && i == (step / 2)) {
                pen.setColor(percentColor);
            }

            //矫正中间值中间格颜色
            if (value == ((maxValue - minValue) / 2 + minValue)) {
                pen.setColor(textColor);
            }
        } else {
            if (rotate <= degRotate) {
                pen.setColor(percentColor);
            } else {
                pen.setColor(textColor);
            }

            //矫正左侧值为最小值时第一格颜色
            if (value == minValue) {
                pen.setColor(textColor);
            }
        }

        painter->setPen(pen);
        painter->drawLine(0, radius - offset, 0, radius);
        painter->rotate(angleStep);
        rotate += angleStep;
    }

    painter->restore();
}

void GaugeMini::drawBgCircle(QPainter *painter)
{
    int radius = 75;
    painter->save();

    QPen pen;
    pen.setWidthF(5.0);
    pen.setColor(borderColor);

    painter->setPen(pen);
    painter->setBrush(bgColor);
    painter->drawEllipse(-radius, -radius, radius * 2, radius * 2);

    painter->restore();
}

void GaugeMini::drawCenterCircle(QPainter *painter)
{
    int radius = 15;
    painter->save();

    QColor color = percentColor;
    if (doublePercent) {
        bool center = (value == (maxValue - minValue) / 2 + minValue);
        color = center ? borderColor : percentColor;
    }

    painter->setPen(Qt::NoPen);
    painter->setBrush(color);
    painter->drawEllipse(-radius, -radius, radius * 2, radius * 2);

    painter->restore();
}