Qt编写自定义控件62-探探雷达

#ifndef SCANTANTAN_H
#define SCANTANTAN_H

/**
 * 探探雷达控件 作者:东门吹雪(QQ:709102202) 整理:feiyangqingyun(QQ:517216493) 2019-10-01
 * 1:可设置中间图像
 * 2:可设置图像的边框宽度+边框颜色,产生圆形图像效果
 * 3:可设置扫描线的最大半径
 * 4:可设置扫描线的边框宽度
 * 5:可设置扩散圈的线条宽度
 * 6:可设置扫描线的每次移动的步长
 * 7:可设置扩散圈的每次移动的步长
 * 8:可设置扫描线的颜色
 * 9:可设置扩散圈的颜色
 */

#include <QWidget>

class QSequentialAnimationGroup;

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

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

{
    Q_OBJECT
    Q_PROPERTY(QPixmap image READ getImage WRITE setImage)
    Q_PROPERTY(int imageBorderWidth READ getImageBorderWidth WRITE setImageBorderWidth)
    Q_PROPERTY(QColor imageBorderColor READ getImageBorderColor WRITE setImageBorderColor)

    Q_PROPERTY(int scanRadius READ getScanRadius WRITE setScanRadius)
    Q_PROPERTY(int scanWidth READ getScanWidth WRITE setScanWidth)
    Q_PROPERTY(int ringWidth READ getRingWidth WRITE setRingWidth)

    Q_PROPERTY(int scanStep READ getScanStep WRITE setScanStep)
    Q_PROPERTY(int ringStep READ getRingStep WRITE setRingStep)

    Q_PROPERTY(QColor scanColor READ getScanColor WRITE setScanColor)
    Q_PROPERTY(QColor ringColor READ getRingColor WRITE setRingColor)

public:
    struct RingData {
        int radius;     //半径
        float width;    //画笔粗细
        int alpha;      //透明度
    };

    explicit ScanTanTan(QWidget *parent = 0);

protected:
    void mousePressEvent(QMouseEvent *);
    void mouseReleaseEvent(QMouseEvent *);
    void paintEvent(QPaintEvent *);
    void drawScan(QPainter *painter);
    void drawRing(QPainter *painter);
    void drawImage(QPainter *painter);

private slots:
    void changeScan();
    void changeRing();
    void updateImage(const QVariant &value);
    double twoPtDistance(const QPointF &pt1, const QPointF &pt2);

private:
    QPixmap image;          //中间图片
    int imageBorderWidth;   //图片边框宽度
    QColor imageBorderColor;//图片边框颜色

    int scanRadius;         //扫描线最大半径
    int scanWidth;          //扫描线边框宽度
    int ringWidth;          //扩散圈线条宽度

    int scanStep;           //扫描线每次移动的步长
    int ringStep;           //扩散圈每次移动的步长

    QColor scanColor;       //扫描线颜色
    QColor ringColor;       //扩散圈颜色

    bool isPressed;         //鼠标是否按下
    int ringRadius;         //扩散圈半径
    int imageRadius;        //图片半径
    int scanDeg;            //当前扫描线角度

    //扩散圈集合,鼠标可能按下多次则产生多个扩散圈,用队列存起来
    QList<RingData> rings;
    //动画组合,用于中间图片的变大放小
    QSequentialAnimationGroup *animationGroup;

public:
    QPixmap getImage()          const;
    int getImageBorderWidth()   const;
    QColor getImageBorderColor()const;

    int getScanRadius()         const;
    int getScanWidth()          const;
    int getRingWidth()          const;

    int getScanStep()           const;
    int getRingStep()           const;

    QColor getScanColor()       const;
    QColor getRingColor()       const;

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

public Q_SLOTS:
    //设置图片+图片边框宽度+图片边框颜色
    void setImage(const QPixmap &image);
    void setImageBorderWidth(int imageBorderWidth);
    void setImageBorderColor(const QColor &imageBorderColor);

    //设置扫描线最大半径+扫描线边框宽度+扩散圈线条宽度
    void setScanRadius(int scanRadius);
    void setScanWidth(int scanWidth);
    void setRingWidth(int ringWidth);

    //设置扫描线步长+扩散圈步长
    void setScanStep(int scanStep);
    void setRingStep(int ringStep);

    //设置扫描线颜色+扩散圈颜色
    void setScanColor(const QColor &scanColor);
    void setRingColor(const QColor &ringColor);
};

#endif // SCANTANTAN_H

void ScanTanTan::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::SmoothPixmapTransform);
    painter.translate(width / 2, height / 2);
    painter.scale(side / 200.0, side / 200.0);

    //绘制扫描线
    drawScan(&painter);
    //绘制扩散圈
    drawRing(&painter);
    //绘制中间图片
    drawImage(&painter);
}

void ScanTanTan::drawScan(QPainter *painter)
{
    painter->save();

    //锥形渐变颜色,通过透明度控制形成扫描效果
    QConicalGradient conicalGradient(0, 0, scanDeg);
    QColor color = scanColor;
    color.setAlpha(50);
    conicalGradient.setColorAt(0, color);
    color.setAlpha(0);
    conicalGradient.setColorAt(1, color);

    //设置画笔画刷
    QPen pen;
    pen.setWidth(scanWidth);
    pen.setBrush(conicalGradient);
    painter->setPen(pen);
    painter->setBrush(conicalGradient);

    //绘制饼圆
    QRect rect(-scanRadius, -scanRadius, scanRadius * 2, scanRadius * 2);
    painter->drawPie(rect, scanDeg * 16, 360 * 16);

    painter->restore();
}

void ScanTanTan::drawRing(QPainter *painter)
{
    painter->save();
    painter->setBrush(Qt::NoBrush);

    //绘制所有扩散圈,扩散圈其实就是个没有背景颜色的圆形
    for (int i = 0; i < rings.count(); i++) {
        RingData ring = rings.at(i);
        int radius = ring.radius;
        float width = ring.width;
        int alpha = 255 - ring.alpha;
        QColor color = ringColor;
        color.setAlpha(alpha);

        QPen pen;
        pen.setWidthF(width);
        pen.setColor(color);
        painter->setPen(pen);
        painter->drawEllipse(-radius, -radius, radius * 2, radius * 2);
    }

    painter->restore();
}

void ScanTanTan::drawImage(QPainter *painter)
{
    painter->save();

    //设置圆形遮罩路径,产生圆形头像效果
    QPainterPath path;
    path.addEllipse(QPoint(0, 0), imageRadius, imageRadius);
    painter->setClipPath(path);

    //绘制图片
    QRect rect(-imageRadius, -imageRadius, imageRadius * 2, imageRadius * 2);
    painter->drawPixmap(rect, image);

    //绘制图片边缘圆形
    QPen pen;
    pen.setWidth(imageBorderWidth);
    pen.setColor(imageBorderColor);
    painter->setPen(pen);
    painter->setBrush(Qt::NoBrush);

    //以下两种方法二选一,其实绘制360度的圆弧=绘制无背景的圆形
    //painter->drawArc(rect, 0, 360 * 16);
    painter->drawEllipse(rect);

    painter->restore();
}