Qt 实现双控制柄的Slider

#include "DoubleHandleSlider.h" #include <QLabel> #include <QVBoxLayout> #include <QPainter> #include <QPainterPath> #include <QMouseEvent> #include <QEnterEvent> #include <QEvent> DoubleHandleSlider::DoubleHandleSlider(int minVal, int maxVal, QWidget *parent) : QWidget(parent) { m_minVal = minVal; m_maxVal = maxVal; m_duration = maxVal- m_minVal; setFixedHeight(50); m_leftHadle = new QLabel(this); m_leftHadle->setObjectName("SliderHandle"); m_leftHadle->setFixedSize(7, 15); m_leftHadle->installEventFilter(this); m_rightHandle = new QLabel(this); m_rightHandle->setObjectName("SliderHandle"); m_rightHandle->setFixedSize(7, 15); m_rightHandle->installEventFilter(this); m_leftValTipsLab = new QLabel(this); m_leftValTipsLab->setObjectName("SliderValTips"); m_leftValTipsLab->setMinimumWidth(50); m_rightValTipsLab = new QLabel(this); m_rightValTipsLab->setObjectName("SliderValTips"); m_rightValTipsLab->setMinimumWidth(50); m_leftVal = minVal; m_rightVal = maxVal; setMouseTracking(true); } void DoubleHandleSlider::setLeftRightVal(int leftVal, int rightVal) { m_leftVal = leftVal; m_rightVal = rightVal; } void DoubleHandleSlider::setHandleIntervalValue(int val) { m_handleIntervalVal = val; } void DoubleHandleSlider::refreshPosition(const float &leftX, const float &rightX) { m_leftHadle->move(leftX, 22); m_rightHandle->move(rightX, 22); int leftTipsTextWidth = m_leftValTipsLab->fontMetrics().boundingRect(QString::number(m_leftVal)).width(); int leftTipsX = leftX- leftTipsTextWidth/2 +2; int rightTipsTextWidht = m_rightValTipsLab->fontMetrics().boundingRect(QString::number(m_rightVal)).width(); int rightTipsX = rightX- rightTipsTextWidht/2 +2; int rightTipXLimit = m_sliderWidth- rightTipsTextWidht- 2; if(leftTipsX< 0) leftTipsX = 0; else if(leftTipsX> rightTipXLimit) leftTipsX = rightTipXLimit; m_leftValTipsLab->move(leftTipsX, 0); if(rightTipsX> rightTipXLimit) rightTipsX = rightTipXLimit; else if(rightTipsX< 0) rightTipsX = 0; m_rightValTipsLab->move(rightTipsX, 0); m_leftValTipsLab->setText(QString::number(m_leftVal)); m_rightValTipsLab->setText(QString::number(m_rightVal)); } void DoubleHandleSlider::refreshLeftVal(float x) { //重新计算左值； m_leftVal = m_duration* x/m_sliderWidth+ m_minVal; // qDebug()<< m_leftVal; if(m_leftVal< m_minVal) m_leftVal = m_minVal; else if(m_leftVal>= m_rightVal- m_handleIntervalVal) m_leftVal = m_rightVal- m_handleIntervalVal; emit valueChanged(m_leftVal, m_rightVal); } void DoubleHandleSlider::refreshRightVal(float x) { //重新计算右值； m_rightVal = m_duration* x/m_sliderWidth+ m_minVal; // qDebug()<< m_rightVal; if(m_rightVal> m_maxVal) m_rightVal = m_maxVal; else if(m_rightVal<= m_leftVal+ m_handleIntervalVal) m_rightVal = m_leftVal+ m_handleIntervalVal; emit valueChanged(m_leftVal, m_rightVal); } void DoubleHandleSlider::paintEvent(QPaintEvent *event) { Q_UNUSED(event); m_sliderWidth = width()- m_rightHandle->width(); //创建painter； QPainter painter(this); painter.setRenderHint(QPainter::Antialiasing, true); //创建pen，pen的作用时描边，因为这里的样式是没有边的，所以需要把pen的类型设为NoPen； QPen pen; pen.setStyle(Qt::PenStyle::NoPen); painter.setPen(pen); //创建画刷，滑槽是通过画刷绘制的，所以这里要设定好滑槽的颜色； QBrush brush(QColor(0x7D, 0x7D, 0x7D)); painter.setBrush(brush); //创建painter 想要绘制的路径，之所以要用这个方法，是因为我们需要画出两端是圆弧形的滑槽；最后两个参数控制了两端圆弧的实现； QPainterPath painterPath; painterPath.addRoundedRect(0, 28, m_sliderWidth, 3, 3, 3); //绘制手柄的两边灰色滑动条； painter.drawPath(painterPath); //画刷更换颜色，继续画另一个滑槽； brush.setColor(QColor(0xFF, 0x55, 0x57)); painter.setBrush(brush); //计算left handle和right handle的位置，同时也是另一个滑槽的两端位置； float leftX = m_sliderWidth* (float)(m_leftVal-m_minVal)/m_duration; float rightX = m_sliderWidth* (float)(m_rightVal-m_minVal)/m_duration; QPainterPath painterPath2; painterPath2.addRoundedRect(leftX, 28, rightX- leftX, 3, 3, 3); //绘制两手柄中间亮色滑动条； painter.drawPath(painterPath2); //刷新handle和tips的位置； refreshPosition(leftX, rightX); } void DoubleHandleSlider::mouseMoveEvent(QMouseEvent *event) { if(m_mouseEnterType == NotInHandle) { //判断鼠标是否在滑动条范围内； if(event->pos().y()< m_leftHadle->y() || event->pos().y()> m_leftHadle->y()+ m_leftHadle->height()) { setCursor(QCursor(Qt::ArrowCursor)); } else { setCursor(QCursor(Qt::PointingHandCursor)); } } else if(m_mouseEnterType == InLeftHandle) { refreshLeftVal(event->pos().x()); update(); } else if(m_mouseEnterType == InRightHandle) { refreshRightVal(event->pos().x()); update(); } } bool DoubleHandleSlider::eventFilter(QObject *watched, QEvent *event) { if(watched == m_leftHadle) { if(event->type() == QEvent::Enter) { setCursor(QCursor(Qt::OpenHandCursor)); m_mouseEnterType = InLeftHandle; } else if(event->type() == QEvent::Leave) { setCursor(QCursor(Qt::OpenHandCursor)); m_mouseEnterType = NotInHandle; } } else if(watched == m_rightHandle) { if(event->type() == QEvent::Enter) { setCursor(QCursor(Qt::OpenHandCursor)); m_mouseEnterType = InRightHandle; } else if(event->type() == QEvent::Leave) { setCursor(QCursor(Qt::OpenHandCursor)); m_mouseEnterType = NotInHandle; } } else { return QWidget::eventFilter(watched, event); } return false; } void DoubleHandleSlider::mousePressEvent(QMouseEvent *event) { //判断鼠标是否在滑动条范围内； if(event->pos().y()< m_leftHadle->y() || event->pos().y()> m_leftHadle->y()+ m_leftHadle->height()) return; if(m_mouseEnterType == NotInHandle) { int handleDuration = m_rightHandle->x()- m_leftHadle->x(); //鼠标在左手柄的左边； if(event->pos().x()< m_leftHadle->x()) refreshLeftVal(event->pos().x()); //鼠标在右手柄的右边； else if(event->pos().x()> m_rightHandle->x()) refreshRightVal(event->pos().x()); //鼠标在两个手柄的中间，但靠近左手柄； else if(event->pos().x()< m_leftHadle->pos().x()+ handleDuration/2) refreshLeftVal(event->pos().x()); //鼠标在两个手柄的中间，但更靠近有手柄； else if(event->pos().x()>= m_leftHadle->pos().x()+ handleDuration/2) refreshRightVal(event->pos().x()); update(); } else if(m_mouseEnterType == InLeftHandle) { setCursor(QCursor(Qt::ClosedHandCursor)); } else if(m_mouseEnterType == InRightHandle) { setCursor(QCursor(Qt::ClosedHandCursor)); } }