Qt编写自定义控件39-导航标签 - QTCN开发网

#ifndef NAVLABEL_H
#define NAVLABEL_H

/**
* 导航标签控件作者:feiyangqingyun(QQ:517216493) 2016-11-28
* 1:可设置前景色和背景色
* 2:可设置箭头位置方向左右上下
* 3:可设置箭头大小
* 4:可设置显示倒三角
* 5:可设置倒三角长度/位置/颜色
*/

#include <QLabel>

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

class QDESIGNER_WIDGET_EXPORT NavLabel : public QLabel
#else
class NavLabel : public QLabel
#endif

{
    Q_OBJECT
    Q_ENUMS(ArrowPosition)
    Q_ENUMS(TrianglePosition)
    Q_PROPERTY(int borderRadius READ getBorderRadius WRITE setBorderRadius)
    Q_PROPERTY(QColor background READ getBackground WRITE setBackground)
    Q_PROPERTY(QColor foreground READ getForeground WRITE setForeground)

    Q_PROPERTY(bool showArrow READ getShowArrow WRITE setShowArrow)
    Q_PROPERTY(int arrowSize READ getArrowSize WRITE setArrowSize)
    Q_PROPERTY(ArrowPosition arrowPosition READ getArrowPosition WRITE setArrowPosition)

    Q_PROPERTY(bool showTriangle READ getShowTriangle WRITE setShowTriangle)
    Q_PROPERTY(int triangleLen READ getTriangleLen WRITE setTriangleLen)
    Q_PROPERTY(TrianglePosition trianglePosition READ getTrianglePosition WRITE setTrianglePosition)
    Q_PROPERTY(QColor triangleColor READ getTriangleColor WRITE setTriangleColor)

public:
    enum ArrowPosition {
        ArrowPosition_Left = 0,     //向左箭头
        ArrowPosition_Right = 1,    //向右箭头
        ArrowPosition_Top = 2,      //向上箭头
        ArrowPosition_Bottom = 3    //向下箭头
    };

    enum TrianglePosition {
        TrianglePosition_Left = 0,  //左侧
        TrianglePosition_Right = 1, //右侧
        TrianglePosition_Top = 2,   //顶部
        TrianglePosition_Bottom = 3 //底部
    };

    explicit NavLabel(QWidget *parent = 0);

protected:
    void mousePressEvent(QMouseEvent *);
    void paintEvent(QPaintEvent *);
    void drawBg(QPainter *painter);
    void drawText(QPainter *painter);
    void drawTriangle(QPainter *painter);

private:
    int borderRadius;                   //边框圆角角度
    QColor background;                  //背景色
    QColor foreground;                  //前景色

    bool showArrow;                     //显示箭头
    int arrowSize;                      //箭头大小
    ArrowPosition arrowPosition;        //箭头位置

    bool showTriangle;                  //显示倒三角
    int triangleLen;                    //倒三角边长
    TrianglePosition trianglePosition;  //倒三角位置
    QColor triangleColor;               //倒三角颜色

    QRect bgRect;                       //绘制区域

public:
    int getBorderRadius()               const;
    QColor getBackground()              const;
    QColor getForeground()              const;

    bool getShowArrow()                 const;
    int getArrowSize()                  const;
    ArrowPosition getArrowPosition()    const;

    bool getShowTriangle()              const;
    int getTriangleLen()                const;
    TrianglePosition getTrianglePosition()const;
    QColor getTriangleColor()           const;

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

public Q_SLOTS:
    //设置边框圆角角度
    void setBorderRadius(int borderRadius);
    //设置前景色
    void setBackground(const QColor &background);
    //设置前景色
    void setForeground(const QColor &foreground);

    //设置显示箭头
    void setShowArrow(bool showArrow);
    //设置箭头大小
    void setArrowSize(int arrowSize);
    //设置箭头位置
    void setArrowPosition(const ArrowPosition &arrowPosition);

    //设置显示倒三角
    void setShowTriangle(bool showTriangle);
    //设置倒三角边长
    void setTriangleLen(int triangleLen);
    //设置倒三角位置
    void setTrianglePosition(const TrianglePosition &trianglePosition);
    //设置倒三角颜色
    void setTriangleColor(const QColor &triangleColor);

Q_SIGNALS:
    void clicked();
};

#endif // NAVLABEL_H

void NavLabel::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
    drawBg(&painter);
    //绘制文字
    drawText(&painter);
    //绘制倒三角
    drawTriangle(&painter);
}

void NavLabel::drawBg(QPainter *painter)
{
    int width = this->width();
    int height = this->height();
    int endX = width - arrowSize;
    int endY = height - arrowSize;

    painter->save();
    painter->setPen(Qt::NoPen);
    painter->setBrush(background);

    QPolygon pts;
    if (arrowPosition == ArrowPosition_Right) {
        bgRect = QRect(0, 0, endX, height);
        pts.setPoints(3, endX, height / 2 - arrowSize, endX, height / 2 + arrowSize, width, height / 2);
    } else if (arrowPosition == ArrowPosition_Left) {
        bgRect = QRect(arrowSize, 0, width - arrowSize, height);
        pts.setPoints(3, arrowSize, height / 2 - arrowSize, arrowSize, height / 2 + arrowSize, 0, height / 2);
    } else if (arrowPosition == ArrowPosition_Bottom) {
        bgRect = QRect(0, 0, width, endY);
        pts.setPoints(3, width / 2 - arrowSize, endY, width / 2 + arrowSize, endY, width / 2, height);
    } else if (arrowPosition == ArrowPosition_Top) {
        bgRect = QRect(0, arrowSize, width, height - arrowSize);
        pts.setPoints(3, width / 2 - arrowSize, arrowSize, width / 2 + arrowSize, arrowSize, width / 2, 0);
    }

    //绘制圆角矩形和三角箭头
    if (!showArrow) {
        bgRect = this->rect();
        painter->drawRoundedRect(bgRect, borderRadius, borderRadius);
    } else {
        painter->drawRoundedRect(bgRect, borderRadius, borderRadius);
        painter->drawPolygon(pts);
    }

    painter->restore();
}

void NavLabel::drawText(QPainter *painter)
{
    painter->save();
    painter->setPen(foreground);
    painter->setBrush(Qt::NoBrush);
    painter->drawText(bgRect, Qt::AlignCenter, this->text());
    painter->restore();
}

void NavLabel::drawTriangle(QPainter *painter)
{
    if (!showTriangle) {
        return;
    }

    painter->save();
    painter->setPen(Qt::NoPen);
    painter->setBrush(triangleColor);

    //绘制在右侧中间,根据设定的倒三角的边长设定三个点位置
    int width = this->width();
    int height = this->height();
    int midWidth = width / 2;
    int midHeight = height / 2;

    QPolygon pts;
    if (trianglePosition == TrianglePosition_Left) {
        pts.setPoints(3, triangleLen, midHeight, 0, midHeight - triangleLen, 0, midHeight + triangleLen);
    } else if (trianglePosition == TrianglePosition_Right) {
        pts.setPoints(3, width - triangleLen, midHeight, width, midHeight - triangleLen, width, midHeight + triangleLen);
    } else if (trianglePosition == TrianglePosition_Top) {
        pts.setPoints(3, midWidth, triangleLen, midWidth - triangleLen, 0, midWidth + triangleLen, 0);
    } else if (trianglePosition == TrianglePosition_Bottom) {
        pts.setPoints(3, midWidth, height - triangleLen, midWidth - triangleLen, height, midWidth + triangleLen, height);
    }

    painter->drawPolygon(pts);

    painter->restore();
}