QT自定义插件Battary

private:

    QColor mColorBack=Qt::white; //背景颜色

    QColor mColorBorder=Qt::black;//电池边框颜色

    QColor mColorPower=Qt::green;//电量柱的颜色

    QColor mColorWarning=Qt::red;//电量低时的颜色

    int mPowerLevel=60;//电量0-100

    int mWarningLevel=20;//电量低阈值

protected:

    void paintEvent(QPaintEvent *event);// Q_DECL_OVERRIDE;

public:

    void setPowerlevel(int pow); //设置当前电量

    int powerlevel();

    void setWarnLevel(int warn);//设置低电量阈值

    int warnLevel();

    QSize sizeHint();//缺省大小

signals:

    void powerLevelChanged(int);

public:

explicit QmyBattery(QmyBattery*parent = nullptr);

　　~QmyBattery();

private slots:

    void on_horizontalSlider_valueChanged(int value);

private:

    Ui::QmyBattery*ui;

void QmyBattery::paintEvent(QPaintEvent *event)

{

    Q_UNUSED(event);

    QPainter painter(this);

    QRect rect(0,0,this->width(),this->height());

    painter.setViewport(rect);

    painter.setWindow(0,0,120,50);

    painter.setRenderHint(QPainter::Antialiasing);

    painter.setRenderHint(QPainter::TextAntialiasing);

    //绘制电池边框

    QPen pen;

    pen.setWidth(2);

    pen.setColor(mColorBorder);

    pen.setStyle(Qt::SolidLine);

    pen.setCapStyle(Qt::FlatCap);

    pen.setJoinStyle(Qt::BevelJoin);

    painter.setPen(pen);

    QBrush brush;

    brush.setColor(mColorBack);

    brush.setStyle(Qt::SolidPattern);

    painter.setBrush(brush);

    rect.setRect(1,1,109,48);

    painter.drawRect(rect); //绘制边框

    brush.setColor(mColorBorder);

    painter.setBrush(brush);

    rect.setRect(110,15,10,20);

    painter.drawRect(rect); //画电池正极头

    //画电池柱

    if(mPowerLevel >mWarningLevel)

    {

        //正常颜色电池柱

        brush.setColor(mColorPower);

        pen.setColor(mColorPower);

    }else {

        brush.setColor(mColorWarning);

        pen.setColor(mColorWarning);

    }

    painter.setBrush(brush);

    painter.setPen(pen);

    if(mPowerLevel >0)

    {

    rect.setRect(5,5,mPowerLevel,40);

    painter.drawRect(rect); //画电池柱

    }

    //绘制电量百分比文字

    QFontMetrics textSize(this->font());

    QString powStr = QString::asprintf("%d%%",mPowerLevel);

    QRect textRect = textSize.boundingRect(powStr); //得到字符串的RECT

    painter.setFont(this->font());

    pen.setColor(mColorBorder);

    painter.setPen(pen);

    painter.drawText(55-textRect.width()/2,23+textRect.height()/2,powStr);

}

void QmyBattery::setPowerlevel(int pow)

{

    mPowerLevel=pow;

    emit powerLevelChanged(pow);

    repaint();

}

int QmyBattery::powerlevel()

{

    return mPowerLevel;

}

void QmyBattery::setWarnLevel(int warn)

{

    mWarningLevel=warn;

    repaint();

}

int QmyBattery::warnLevel()

{

    return  mWarningLevel;

}

QSize QmyBattery::sizeHint()

{

    int H= this->height();

    int W= H*12/5;

    QSize size(W,H);

    return  size;

}

void QmyBattery::on_horizontalSlider_valueChanged(int value)

{

    ui->battery->setPowerLevel(value);

    QString str = QStringLiteral("当前电量")+QString::asprintf("%d%%",value);

    ui->label->setText(str);

}