Qt编写自定义控件29-颜色选取面板 - QTCN开发网

#ifndef COLORPANELHSB_H
#define COLORPANELHSB_H

/**
* 颜色选取面板作者:feiyangqingyun(QQ:517216493) 2017-11-17
* 1:可设置当前百分比,用于控制指针大小
* 2:可设置边框宽度
* 3:可设置边框颜色
* 4:可设置指针颜色
*/

#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 ColorPanelHSB : public QWidget
#else
class ColorPanelHSB : public QWidget
#endif

{
    Q_OBJECT
    Q_PROPERTY(int percent READ getPercent WRITE setPercent)
    Q_PROPERTY(QColor borderColor READ getBorderColor WRITE setBorderColor)
    Q_PROPERTY(QColor cursorColor READ getCursorColor WRITE setCursorColor)

    Q_PROPERTY(QColor color READ getColor)
    Q_PROPERTY(double hue READ getHue)
    Q_PROPERTY(double sat READ getSat)

public:
    explicit ColorPanelHSB(QWidget *parent = 0);

protected:
    void showEvent(QShowEvent *);
    void resizeEvent(QResizeEvent *);
    void mousePressEvent(QMouseEvent *e);
    void mouseMoveEvent(QMouseEvent *e);
    void paintEvent(QPaintEvent *);
    void drawBg(QPainter *painter);
    void drawCursor(QPainter *painter);
    void drawBorder(QPainter *painter);

private:
    int percent;                //当前百分比
    int borderWidth;            //边框宽度
    QColor borderColor;         //边框颜色
    QColor cursorColor;         //鼠标按下处的文字形状颜色

    QColor color;               //鼠标按下处的颜色
    double hue;                 //hue值
    double sat;                 //sat值

    QPoint lastPos;             //最后鼠标按下去的坐标
    QPixmap bgPix;              //背景颜色图片

public:
    int getPercent()            const;
    QColor getBorderColor()     const;
    QColor getCursorColor()     const;

    QColor getColor()           const;
    double getHue()             const;
    double getSat()             const;

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

public Q_SLOTS:
    //设置百分比
    void setPercent(int percent);

    //设置边框颜色
    void setBorderColor(const QColor &borderColor);

    //设置文字形状颜色
    void setCursorColor(const QColor &cursorColor);

Q_SIGNALS:
    void colorChanged(const QColor &color, double hue, double sat);

};

#endif // COLORPANELHSB_H

void ColorPanelHSB::paintEvent(QPaintEvent *)
{
    //绘制准备工作,启用反锯齿
    QPainter painter(this);
    painter.setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);

    //绘制背景颜色
    drawBg(&painter);
    //绘制按下出的形状
    drawCursor(&painter);
    //绘制边框
    drawBorder(&painter);
}

void ColorPanelHSB::drawBg(QPainter *painter)
{
    painter->save();

    if (!bgPix.isNull()) {
        painter->drawPixmap(0, 0, bgPix);
    }

    painter->restore();
}

void ColorPanelHSB::drawCursor(QPainter *painter)
{
    painter->save();
    painter->setPen(cursorColor);

    QString text = "+";

    //根据右侧的百分比显示字体大小
    QFont textFont;
    int size = 20 + (35 * (double)percent / 100);
    textFont.setPixelSize(size);

    //计算文字的宽度高度,自动移到鼠标按下处的中心点
    QFontMetrics fm(textFont);
    int textWidth = fm.width(text);
    int textHeight = fm.height();
    QPoint textPoint = lastPos - QPoint(textWidth / 2, -(textHeight / 4));

    QPainterPath path;
    path.addText(textPoint, textFont, text);
    painter->drawPath(path);

    painter->restore();
}

void ColorPanelHSB::drawBorder(QPainter *painter)
{
    painter->save();

    int width = this->width();
    int height = this->height();
    int offset = borderWidth;

    QPen pen;
    pen.setWidth(offset);
    pen.setColor(borderColor);
    pen.setCapStyle(Qt::RoundCap);
    pen.setJoinStyle(Qt::MiterJoin);

    painter->setPen(pen);
    painter->setBrush(Qt::NoBrush);
    painter->drawRect(offset / 2, offset / 2, width - offset, height - offset);

    painter->restore();
}