Qt编写自定义控件43-自绘电池 - QTCN开发网

#ifndef BATTERY_H
#define BATTERY_H

/**
* 电池电量控件作者:feiyangqingyun(QQ:517216493) 2016-10-23
* 1:可设置电池电量,动态切换电池电量变化
* 2:可设置电池电量警戒值
* 3:可设置电池电量正常颜色和报警颜色
* 4:可设置边框渐变颜色
* 5:可设置电量变化时每次移动的步长
* 6:可设置边框圆角角度/背景进度圆角角度/头部圆角角度
*/

#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 Battery : public QWidget
#else
class Battery : public QWidget
#endif

{
    Q_OBJECT
    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(double alarmValue READ getAlarmValue WRITE setAlarmValue)

    Q_PROPERTY(double step READ getStep WRITE setStep)
    Q_PROPERTY(int borderRadius READ getBorderRadius WRITE setBorderRadius)
    Q_PROPERTY(int bgRadius READ getBgRadius WRITE setBgRadius)
    Q_PROPERTY(int headRadius READ getHeadRadius WRITE setHeadRadius)

    Q_PROPERTY(QColor borderColorStart READ getBorderColorStart WRITE setBorderColorStart)
    Q_PROPERTY(QColor borderColorEnd READ getBorderColorEnd WRITE setBorderColorEnd)

    Q_PROPERTY(QColor alarmColorStart READ getAlarmColorStart WRITE setAlarmColorStart)
    Q_PROPERTY(QColor alarmColorEnd READ getAlarmColorEnd WRITE setAlarmColorEnd)

    Q_PROPERTY(QColor normalColorStart READ getNormalColorStart WRITE setNormalColorStart)
    Q_PROPERTY(QColor normalColorEnd READ getNormalColorEnd WRITE setNormalColorEnd)

public:
    explicit Battery(QWidget *parent = 0);
    ~Battery();

protected:
    void paintEvent(QPaintEvent *);
    void drawBorder(QPainter *painter);
    void drawBg(QPainter *painter);
    void drawHead(QPainter *painter);

private slots:
    void updateValue();

private:
    double minValue;                //最小值
    double maxValue;                //最大值
    double value;                   //目标电量
    double alarmValue;              //电池电量警戒值

    double step;                    //每次移动的步长
    int borderRadius;               //边框圆角角度
    int bgRadius;                   //背景进度圆角角度
    int headRadius;                 //头部圆角角度

    QColor borderColorStart;        //边框渐变开始颜色
    QColor borderColorEnd;          //边框渐变结束颜色

    QColor alarmColorStart;         //电池低电量时的渐变开始颜色
    QColor alarmColorEnd;           //电池低电量时的渐变结束颜色

    QColor normalColorStart;        //电池正常电量时的渐变开始颜色
    QColor normalColorEnd;          //电池正常电量时的渐变结束颜色

    bool isForward;                 //是否往前移
    double currentValue;            //当前电量
    QRectF batteryRect;             //电池主体区域
    QTimer *timer;                  //绘制定时器

public:
    double getMinValue()            const;
    double getMaxValue()            const;
    double getValue()               const;
    double getAlarmValue()          const;

    double getStep()                const;
    int getBorderRadius()           const;
    int getBgRadius()               const;
    int getHeadRadius()             const;

    QColor getBorderColorStart()    const;
    QColor getBorderColorEnd()      const;

    QColor getAlarmColorStart()     const;
    QColor getAlarmColorEnd()       const;

    QColor getNormalColorStart()    const;
    QColor getNormalColorEnd()      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);

    //设置电池电量值
    void setValue(double value);
    void setValue(int value);

    //设置电池电量警戒值
    void setAlarmValue(double alarmValue);
    void setAlarmValue(int alarmValue);

    //设置步长
    void setStep(double step);
    void setStep(int step);

    //设置边框圆角角度
    void setBorderRadius(int borderRadius);
    //设置背景圆角角度
    void setBgRadius(int bgRadius);
    //设置头部圆角角度
    void setHeadRadius(int headRadius);

    //设置边框渐变颜色
    void setBorderColorStart(const QColor &borderColorStart);
    void setBorderColorEnd(const QColor &borderColorEnd);

    //设置电池电量报警时的渐变颜色
    void setAlarmColorStart(const QColor &alarmColorStart);
    void setAlarmColorEnd(const QColor &alarmColorEnd);

    //设置电池电量正常时的渐变颜色
    void setNormalColorStart(const QColor &normalColorStart);
    void setNormalColorEnd(const QColor &normalColorEnd);

Q_SIGNALS:
    void valueChanged(double value);
};

#endif // BATTERY_H

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

    //绘制边框
    drawBorder(&painter);
    //绘制背景
    drawBg(&painter);
    //绘制头部
    drawHead(&painter);
}

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

    double headWidth = width() / 10;
    double batteryWidth = width() - headWidth;

    //绘制电池边框
    QPointF topLeft(5, 5);
    QPointF bottomRight(batteryWidth, height() - 5);
    batteryRect = QRectF(topLeft, bottomRight);

    painter->setPen(QPen(borderColorStart, 5));
    painter->setBrush(Qt::NoBrush);
    painter->drawRoundedRect(batteryRect, borderRadius, borderRadius);

    painter->restore();
}

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

    QLinearGradient batteryGradient(QPointF(0, 0), QPointF(0, height()));
    if (currentValue <= alarmValue) {
        batteryGradient.setColorAt(0.0, alarmColorStart);
        batteryGradient.setColorAt(1.0, alarmColorEnd);
    } else {
        batteryGradient.setColorAt(0.0, normalColorStart);
        batteryGradient.setColorAt(1.0, normalColorEnd);
    }

    int margin = qMin(width(), height()) / 20;
    double unit = (batteryRect.width() - (margin * 2)) / 100;
    double width = currentValue * unit;
    QPointF topLeft(batteryRect.topLeft().x() + margin, batteryRect.topLeft().y() + margin);
    QPointF bottomRight(width + margin + 5, batteryRect.bottomRight().y() - margin);
    QRectF rect(topLeft, bottomRight);

    painter->setPen(Qt::NoPen);
    painter->setBrush(batteryGradient);
    painter->drawRoundedRect(rect, bgRadius, bgRadius);

    painter->restore();
}

void Battery::drawHead(QPainter *painter)
{
    painter->save();

    QPointF headRectTopLeft(batteryRect.topRight().x(), height() / 3);
    QPointF headRectBottomRight(width(), height() - height() / 3);
    QRectF headRect(headRectTopLeft, headRectBottomRight);

    QLinearGradient headRectGradient(headRect.topLeft(), headRect.bottomLeft());
    headRectGradient.setColorAt(0.0, borderColorStart);
    headRectGradient.setColorAt(1.0, borderColorEnd);

    painter->setPen(Qt::NoPen);
    painter->setBrush(headRectGradient);
    painter->drawRoundedRect(headRect, headRadius, headRadius);

    painter->restore();
}