Qt开源作品30-农历控件

一、前言

农历控件在国产linux中必备的控件之一，毕竟要适应国人的习惯，你看win10系统的日历，现在点开来直接就有农历在上面，非常方便人性化，所以在很多用Qt做的项目中，也有农历控件的应用场景，而Qt自带的日历控件比较简单，仔细看过源码的人也只知道，其实就是一堆微调框，下拉框，表格组成的，于是打算借用此方法造一个农历控件，本控件的算法是倪大侠提供的，个人测试下来还是没有问题的，造这个农历控件最大的难点是如何根据日期计算农历时间，再加上一些农历的节气之类的，这个网上估计也有很多的算法参考。

主要功能：

1. 可设置边框颜色/周末颜色/角标颜色/农历节日颜色
2. 可设置当前月文字颜色/其他月文字颜色/选中日期文字颜色/悬停日期文字颜色
3. 可设置当前月农历文字颜色/其他月农历文字颜色/选中日期农历文字颜色/悬停日期农历文字颜色
4. 可设置当前月背景颜色/其他月背景颜色/选中日期背景颜色/悬停日期背景颜色
5. 可设置三种选中背景模式,矩形背景+圆形背景+图片背景
6. 可直接切换到上一年/下一年/上一月/下一月/转到今天
7. 可设置是否显示农历信息,不显示则当做正常的日历使用
8. 支持1900年-2099年范围
9. 很方便改成多选日期

二、代码思路

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

    //绘制背景和边框
    drawBg(&painter);

    //优先绘制选中状态,其次绘制悬停状态
    if (select) {
        drawBgCurrent(&painter, selectBgColor);
    } else if (hover) {
        drawBgCurrent(&painter, hoverBgColor);
    }

    //绘制日期
    drawDay(&painter);

    //绘制农历信息
    drawLunar(&painter);
}

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

    //根据当前类型选择对应的颜色
    QColor bgColor = currentBgColor;
    if (dayType == DayType_MonthPre || dayType == DayType_MonthNext) {
        bgColor = otherBgColor;
    }

    painter->setPen(borderColor);
    painter->setBrush(bgColor);
    painter->drawRect(rect());

    painter->restore();
}

void LunarCalendarItem::drawBgCurrent(QPainter *painter, const QColor &color)
{
    int width = this->width();
    int height = this->height();
    int side = qMin(width, height);

    painter->save();

    painter->setPen(Qt::NoPen);
    painter->setBrush(color);

    //根据设定绘制背景样式
    if (selectType == SelectType_Rect) {
        painter->drawRect(rect());
    } else if (selectType == SelectType_Circle) {
        int radius = side / 2 - 3;
        painter->drawEllipse(QPointF(width / 2, height / 2), radius, radius);
    } else if (selectType == SelectType_Triangle) {
        int radius = side / 3;
        QPolygon pts;
        pts.setPoints(3, 1, 1, radius, 1, 1, radius);
        painter->drawRect(rect());
        painter->setBrush(superColor);
        painter->drawConvexPolygon(pts);
    } else if (selectType == SelectType_Image) {
        //等比例缩放居中绘制
        QImage img(bgImage);
        if (!img.isNull()) {
            img = img.scaled(this->size(), Qt::KeepAspectRatio, Qt::SmoothTransformation);
            int x = (width - img.width()) / 2;
            int y = (height - img.height()) / 2;
            painter->drawImage(x, y, img);
        }
    }

    painter->restore();
}

void LunarCalendarItem::drawDay(QPainter *painter)
{
    int width = this->width();
    int height = this->height();
    int side = qMin(width, height);

    painter->save();

    //根据当前类型选择对应的颜色
    QColor color = currentTextColor;
    if (dayType == DayType_MonthPre || dayType == DayType_MonthNext) {
        color = otherTextColor;
    } else if (dayType == DayType_WeekEnd) {
        color = weekColor;
    }

    if (select) {
        color = selectTextColor;
    } else if (hover) {
        color = hoverTextColor;
    }

    painter->setPen(color);

    if (showLunar) {
        QFont font;
        font.setPixelSize(side / 2.7);
        painter->setFont(font);

        QRect dayRect = QRect(0, 0, width, height / 1.7);
        painter->drawText(dayRect, Qt::AlignHCenter | Qt::AlignBottom, QString::number(date.day()));
    } else {
        QFont font;
        font.setPixelSize(side / 2);
        painter->setFont(font);

        QRect dayRect = QRect(0, 0, width, height);
        painter->drawText(dayRect, Qt::AlignCenter, QString::number(date.day()));
    }

    painter->restore();
}

void LunarCalendarItem::drawLunar(QPainter *painter)
{
    if (!showLunar) {
        return;
    }

    int width = this->width();
    int height = this->height();
    int side = qMin(width, height);

    painter->save();

    //判断当前农历文字是否节日,是节日且是当月则用农历节日颜色显示
    bool exist = (!listDayName.contains(lunar) && dayType != DayType_MonthPre && dayType != DayType_MonthNext);

    //根据当前类型选择对应的颜色
    QColor color = currentLunarColor;
    if (dayType == DayType_MonthPre || dayType == DayType_MonthNext) {
        color = otherLunarColor;
    }

    if (select) {
        color = selectTextColor;
    } else if (hover) {
        color = hoverTextColor;
    } else if (exist) {
        color = lunarColor;
    }

    painter->setPen(color);

    QFont font;
    font.setPixelSize(side / 5);
    painter->setFont(font);    

    QRect lunarRect(0, height / 2, width, height / 2);
    painter->drawText(lunarRect, Qt::AlignCenter, lunar);

    painter->restore();
}

三、效果图

四、开源主页

以上作品完整源码下载都在开源主页，会持续不断更新作品数量和质量，欢迎各位关注。

1. 国内站点：https://gitee.com/feiyangqingyun/QWidgetDemo
2. 国际站点：https://github.com/feiyangqingyun/QWidgetDemo
3. 个人主页：https://blog.csdn.net/feiyangqingyun
4. 知乎主页：https://www.zhihu.com/people/feiyangqingyun/