目录

说明：这里参考许多大佬资料，但是当时记着赶项目，忘记搜集大佬们链接，非常感谢大佬们无私奉献。

1.继承QWidget

2.继承QSlider（有缺陷，部分功能没有实现，可以研究一下）

3.继承QWidget与1有点异曲同工之处（也是自绘）

4.使用小聪明，但是可以使用Qt样式

说明：这里参考许多大佬资料，但是当时记着赶项目，忘记搜集大佬们链接，非常感谢大佬们无私奉献。

1.继承QWidget

如果项目需求对QSlider要求不高（使用自绘方法，无法使用样式）继承QWidget，里面基本功能都实现了，个别需要自己在研究实现，效果如如下

#pragma once#include 
#include 
#include class RangeSlider : public QWidget
{Q_OBJECTQ_ENUMS(RangeSliderTypes)public:enum Option {NoHandle = 0x0,LeftHandle = 0x1,RightHandle = 0x2,DoubleHandles = LeftHandle | RightHandle};Q_DECLARE_FLAGS(Options, Option)RangeSlider( QWidget* aParent = Q_NULLPTR);RangeSlider( Qt::Orientation ori, Options t = DoubleHandles, QWidget* aParent = Q_NULLPTR);QSize minimumSizeHint() const override;int GetMinimun() const;void SetMinimum(int aMinimum);int GetMaximun() const;void SetMaximum(int aMaximum);int GetLowerValue() const;void SetLowerValue(int aLowerValue);int GetUpperValue() const;void SetUpperValue(int aUpperValue);void SetRange(int aMinimum, int aMaximum);protected:void paintEvent(QPaintEvent* aEvent) override;void mousePressEvent(QMouseEvent* aEvent) override;void mouseMoveEvent(QMouseEvent* aEvent) override;void mouseReleaseEvent(QMouseEvent* aEvent) override;void changeEvent(QEvent* aEvent) override;QRectF firstHandleRect() const;QRectF secondHandleRect() const;QRectF handleRect(int aValue) const;signals:void lowerValueChanged(int aLowerValue);void upperValueChanged(int aUpperValue);void rangeChanged(int aMin, int aMax);public slots:void setLowerValue(int aLowerValue);void setUpperValue(int aUpperValue);void setMinimum(int aMinimum);void setMaximum(int aMaximum);private:Q_DISABLE_COPY(RangeSlider)float currentPercentage();int validLength() const;int mMinimum;int mMaximum;int mLowerValue;int mUpperValue;bool mFirstHandlePressed;bool mSecondHandlePressed;int mInterval;int mDelta;QColor mBackgroudColorEnabled;QColor mBackgroudColorDisabled;QColor mBackgroudColor;Qt::Orientation orientation;Options type;
};Q_DECLARE_OPERATORS_FOR_FLAGS(RangeSlider::Options)

#include "RangeSlider.h"
#include namespace
{const int scHandleSideLength = 11;
const int scSliderBarHeight = 5;
const int scLeftRightMargin = 1;}RangeSlider::RangeSlider(QWidget* aParent): QWidget(aParent),mMinimum(0),mMaximum(100),mLowerValue(0),mUpperValue(100),mFirstHandlePressed(false),mSecondHandlePressed(false),mInterval(mMaximum - mMinimum),mBackgroudColorEnabled(QColor(0x1E, 0x90, 0xFF)),mBackgroudColorDisabled(Qt::darkGray),mBackgroudColor(mBackgroudColorEnabled),orientation(Qt::Horizontal)
{setMouseTracking(true);
}RangeSlider::RangeSlider(Qt::Orientation ori, Options t, QWidget* aParent): QWidget(aParent),mMinimum(0),mMaximum(100),mLowerValue(0),mUpperValue(100),mFirstHandlePressed(false),mSecondHandlePressed(false),mInterval(mMaximum - mMinimum),mBackgroudColorEnabled(QColor(0x1E, 0x90, 0xFF)),mBackgroudColorDisabled(Qt::darkGray),mBackgroudColor(mBackgroudColorEnabled),orientation(ori),type(t)
{setMouseTracking(true);
}void RangeSlider::paintEvent(QPaintEvent* aEvent)
{Q_UNUSED(aEvent);QPainter painter(this);// BackgroundQRectF backgroundRect;if(orientation == Qt::Horizontal)backgroundRect = QRectF(scLeftRightMargin, (height() - scSliderBarHeight) / 2, width() - scLeftRightMargin * 2, scSliderBarHeight);elsebackgroundRect = QRectF((width() - scSliderBarHeight) / 2, scLeftRightMargin, scSliderBarHeight, height() - scLeftRightMargin*2);QPen pen(Qt::gray, 0.8);painter.setPen(pen);painter.setRenderHint(QPainter::Qt4CompatiblePainting);QBrush backgroundBrush(QColor(0xD0, 0xD0, 0xD0));painter.setBrush(backgroundBrush);painter.drawRoundedRect(backgroundRect, 1, 1);// First value handle rectpen.setColor(Qt::darkGray);pen.setWidth(0.5);painter.setPen(pen);painter.setRenderHint(QPainter::Antialiasing);QBrush handleBrush(QColor(0xFA, 0xFA, 0xFA));painter.setBrush(handleBrush);QRectF leftHandleRect = firstHandleRect();if(type.testFlag(LeftHandle))painter.drawRoundedRect(leftHandleRect, 2, 2);// Second value handle rectQRectF rightHandleRect = secondHandleRect();if(type.testFlag(RightHandle))painter.drawRoundedRect(rightHandleRect, 2, 2);// Handlespainter.setRenderHint(QPainter::Antialiasing, false);QRectF selectedRect(backgroundRect);if(orientation == Qt::Horizontal) {selectedRect.setLeft((type.testFlag(LeftHandle) ? leftHandleRect.right() : leftHandleRect.left()) + 0.5);selectedRect.setRight((type.testFlag(RightHandle) ? rightHandleRect.left() : rightHandleRect.right()) - 0.5);} else {selectedRect.setTop((type.testFlag(LeftHandle) ? leftHandleRect.bottom() : leftHandleRect.top()) + 0.5);selectedRect.setBottom((type.testFlag(RightHandle) ? rightHandleRect.top() : rightHandleRect.bottom()) - 0.5);}QBrush selectedBrush(mBackgroudColor);painter.setBrush(selectedBrush);painter.drawRect(selectedRect);
}QRectF RangeSlider::firstHandleRect() const
{float percentage = (mLowerValue - mMinimum) * 1.0 / mInterval;return handleRect(percentage * validLength() + scLeftRightMargin);
}QRectF RangeSlider::secondHandleRect() const
{float percentage = (mUpperValue - mMinimum) * 1.0 / mInterval;return handleRect(percentage * validLength() + scLeftRightMargin + (type.testFlag(LeftHandle) ? scHandleSideLength : 0));
}QRectF RangeSlider::handleRect(int aValue) const
{if(orientation == Qt::Horizontal)return QRect(aValue, (height()-scHandleSideLength) / 2, scHandleSideLength, scHandleSideLength);elsereturn QRect((width()-scHandleSideLength) / 2, aValue, scHandleSideLength, scHandleSideLength);
}void RangeSlider::mousePressEvent(QMouseEvent* aEvent)
{if(aEvent->buttons() & Qt::LeftButton){int posCheck, posMax, posValue, firstHandleRectPosValue, secondHandleRectPosValue;posCheck = (orientation == Qt::Horizontal) ? aEvent->pos().y() : aEvent->pos().x();posMax = (orientation == Qt::Horizontal) ? height() : width();posValue = (orientation == Qt::Horizontal) ? aEvent->pos().x() : aEvent->pos().y();firstHandleRectPosValue = (orientation == Qt::Horizontal) ? firstHandleRect().x() : firstHandleRect().y();secondHandleRectPosValue = (orientation == Qt::Horizontal) ? secondHandleRect().x() : secondHandleRect().y();mSecondHandlePressed = secondHandleRect().contains(aEvent->pos());mFirstHandlePressed = !mSecondHandlePressed && firstHandleRect().contains(aEvent->pos());if(mFirstHandlePressed){mDelta = posValue - (firstHandleRectPosValue + scHandleSideLength / 2);}else if(mSecondHandlePressed){mDelta = posValue - (secondHandleRectPosValue + scHandleSideLength / 2);}if(posCheck >= 2&& posCheck <= posMax - 2){int step = mInterval / 10 < 1 ? 1 : mInterval / 10;if(posValue < firstHandleRectPosValue)setLowerValue(mLowerValue - step);else if(((posValue > firstHandleRectPosValue + scHandleSideLength) || !type.testFlag(LeftHandle))&& ((posValue < secondHandleRectPosValue) || !type.testFlag(RightHandle))){if(type.testFlag(DoubleHandles))if(posValue - (firstHandleRectPosValue + scHandleSideLength) <(secondHandleRectPosValue - (firstHandleRectPosValue + scHandleSideLength)) / 2)setLowerValue((mLowerValue + step < mUpperValue) ? mLowerValue + step : mUpperValue);elsesetUpperValue((mUpperValue - step > mLowerValue) ? mUpperValue - step : mLowerValue);else if(type.testFlag(LeftHandle))setLowerValue((mLowerValue + step < mUpperValue) ? mLowerValue + step : mUpperValue);else if(type.testFlag(RightHandle))setUpperValue((mUpperValue - step > mLowerValue) ? mUpperValue - step : mLowerValue);}else if(posValue > secondHandleRectPosValue + scHandleSideLength)setUpperValue(mUpperValue + step);}}
}void RangeSlider::mouseMoveEvent(QMouseEvent* aEvent)
{if(aEvent->buttons() & Qt::LeftButton){int posValue, firstHandleRectPosValue, secondHandleRectPosValue;posValue = (orientation == Qt::Horizontal) ? aEvent->pos().x() : aEvent->pos().y();firstHandleRectPosValue = (orientation == Qt::Horizontal) ? firstHandleRect().x() : firstHandleRect().y();secondHandleRectPosValue = (orientation == Qt::Horizontal) ? secondHandleRect().x() : secondHandleRect().y();if(mFirstHandlePressed && type.testFlag(LeftHandle)){if(posValue - mDelta + scHandleSideLength / 2 <= secondHandleRectPosValue){setLowerValue((posValue - mDelta - scLeftRightMargin - scHandleSideLength / 2) * 1.0 / validLength() * mInterval + mMinimum);}else{setLowerValue(mUpperValue);}}else if(mSecondHandlePressed && type.testFlag(RightHandle)){if(firstHandleRectPosValue + scHandleSideLength * (type.testFlag(DoubleHandles) ? 1.5 : 0.5) <= posValue - mDelta){setUpperValue((posValue - mDelta - scLeftRightMargin - scHandleSideLength / 2 - (type.testFlag(DoubleHandles) ? scHandleSideLength : 0)) * 1.0 / validLength() * mInterval + mMinimum);}else{setUpperValue(mLowerValue);}}}
}void RangeSlider::mouseReleaseEvent(QMouseEvent* aEvent)
{Q_UNUSED(aEvent);mFirstHandlePressed = false;mSecondHandlePressed = false;
}void RangeSlider::changeEvent(QEvent* aEvent)
{if(aEvent->type() == QEvent::EnabledChange){if(isEnabled()){mBackgroudColor = mBackgroudColorEnabled;}else{mBackgroudColor = mBackgroudColorDisabled;}update();}
}QSize RangeSlider::minimumSizeHint() const
{return QSize(scHandleSideLength * 2 + scLeftRightMargin * 2, scHandleSideLength);
}int RangeSlider::GetMinimun() const
{return mMinimum;
}void RangeSlider::SetMinimum(int aMinimum)
{setMinimum(aMinimum);
}int RangeSlider::GetMaximun() const
{return mMaximum;
}void RangeSlider::SetMaximum(int aMaximum)
{setMaximum(aMaximum);
}int RangeSlider::GetLowerValue() const
{return mLowerValue;
}void RangeSlider::SetLowerValue(int aLowerValue)
{setLowerValue(aLowerValue);
}int RangeSlider::GetUpperValue() const
{return mUpperValue;
}void RangeSlider::SetUpperValue(int aUpperValue)
{setUpperValue(aUpperValue);
}void RangeSlider::setLowerValue(int aLowerValue)
{if(aLowerValue > mMaximum){aLowerValue = mMaximum;}if(aLowerValue < mMinimum){aLowerValue = mMinimum;}mLowerValue = aLowerValue;emit lowerValueChanged(mLowerValue);update();
}void RangeSlider::setUpperValue(int aUpperValue)
{if(aUpperValue > mMaximum){aUpperValue = mMaximum;}if(aUpperValue < mMinimum){aUpperValue = mMinimum;}mUpperValue = aUpperValue;emit upperValueChanged(mUpperValue);update();
}void RangeSlider::setMinimum(int aMinimum)
{if(aMinimum <= mMaximum){mMinimum = aMinimum;}else{int oldMax = mMaximum;mMinimum = oldMax;mMaximum = aMinimum;}mInterval = mMaximum - mMinimum;update();setLowerValue(mMinimum);setUpperValue(mMaximum);emit rangeChanged(mMinimum, mMaximum);
}void RangeSlider::setMaximum(int aMaximum)
{if(aMaximum >= mMinimum){mMaximum = aMaximum;}else{int oldMin = mMinimum;mMaximum = oldMin;mMinimum = aMaximum;}mInterval = mMaximum - mMinimum;update();setLowerValue(mMinimum);setUpperValue(mMaximum);emit rangeChanged(mMinimum, mMaximum);
}int RangeSlider::validLength() const
{int len = (orientation == Qt::Horizontal) ? width() : height();return len - scLeftRightMargin * 2 - scHandleSideLength * (type.testFlag(DoubleHandles) ? 2 : 1);
}void RangeSlider::SetRange(int aMinimum, int mMaximum)
{setMinimum(aMinimum);setMaximum(mMaximum);
}

//调用方法 这里只写代码段 .h
QHBoxLayout *layout;
RangeSlider *rsH, *rsV, *rsHsingleLeft, *rsVsingleLeft, *rsHsingleRight, *rsVsingleRight;//.cpp
rsH = new RangeSlider(Qt::Horizontal, RangeSlider::Option::DoubleHandles, nullptr);rsV = new RangeSlider(Qt::Vertical, RangeSlider::Option::DoubleHandles, nullptr);rsHsingleLeft = new RangeSlider(Qt::Horizontal, RangeSlider::Option::LeftHandle, nullptr);rsVsingleLeft = new RangeSlider(Qt::Vertical, RangeSlider::Option::LeftHandle, nullptr);rsHsingleRight = new RangeSlider(Qt::Horizontal, RangeSlider::Option::RightHandle, nullptr);rsVsingleRight = new RangeSlider(Qt::Vertical, RangeSlider::Option::RightHandle, nullptr);
layout = new QHBoxLayout();
layout->addWidget(rsH);
layout->addWidget(rsV);
layout->addWidget(rsHsingleLeft);
layout->addWidget(rsVsingleLeft);
layout->addWidget(rsHsingleRight);
layout->addWidget(rsVsingleRight);
widget->setLayout(layout);
setCentralWidget(widget);
resize(QDesktopWidget().availableGeometry(this).size() * 0.7);

2.继承QSlider（有缺陷，部分功能没有实现，可以研究一下）

 该方法使用QPixmap贴图方式，然后将贴图在滑条范围内移动，下面分别是.h和cpp

#ifndef SUPERSLIDER_H
#define SUPERSLIDER_H#pragma once#include "qslider.h"
#include "qlabel.h"/*
*  Super sick nasty awesome double handled slider!
*
*   @author Steve
*/
class SuperSliderHandle;class SuperSlider: public QSlider
{Q_OBJECT
public:SuperSlider(QWidget *parent = 0);SuperSliderHandle *alt_handle;void mouseReleaseEvent(QMouseEvent *event);int alt_value();void alt_setValue(int value);void Reset();void alt_update();
signals:void alt_valueChanged(int);
};class SuperEventFilter : public QObject
{
public:SuperEventFilter(SuperSlider *_grandParent){grandParent = _grandParent;};protected:bool eventFilter(QObject* obj, QEvent* event);private:SuperSlider *grandParent;
};class SuperSliderHandle: public QLabel
{Q_OBJECT
public:SuperSliderHandle(SuperSlider *parent = 0);void mousePressEvent(QMouseEvent *event);int value();int mapValue();SuperSlider *parent;bool handleActivated;
private:SuperEventFilter *filter;public slots:void setValue(double value);
};#endif // SUPERSLIDER_H

#include "SuperSlider.h"
//Qt
#include 
#include "qmimedata.h"
#include "qdrag.h"
#include "qwidgetaction.h"
#include "qapplication.h"
#include "qpixmap.h"
#include "qcursor.h"
#include "qguiapplication.h"
#include "qdir.h"
#include class SliderProxy : public QProxyStyle
{
public:int pixelMetric ( PixelMetric metric, const QStyleOption * option = 0, const QWidget * widget = 0 ) const{switch(metric) {case PM_SliderThickness  : return 25;case PM_SliderLength     : return 25;default                  : return (QProxyStyle::pixelMetric(metric,option,widget));}}
};SuperSlider::SuperSlider(QWidget *parent): QSlider(parent)
{//stylingsetOrientation(Qt::Horizontal);setAcceptDrops(true);SliderProxy *aSliderProxy = new SliderProxy();//hard coded path to image :/ sorryQString path = "d:/1.png";// QDir::fromNativeSeparators(ImagesPath("handle.png"));setStyleSheet("QSlider::handle { image: url(" + path + "); }");setStyle(aSliderProxy);//setting up the alternate handlealt_handle = new SuperSliderHandle(this);addAction(new QWidgetAction(alt_handle));alt_handle->move(this->pos().x() + this->width()- alt_handle->width(), this->pos().y() );}SuperSliderHandle::SuperSliderHandle(SuperSlider *_parent): QLabel(_parent)
{parent = _parent;filter = new SuperEventFilter(parent);//stylingsetAcceptDrops(true);//hard coded path to image :/ sorryQPixmap pix = QPixmap("d:/2.png");//QPixmap(ImagesPath("handle.png"));pix =  pix.scaled(25, 25, Qt::IgnoreAspectRatio, Qt::SmoothTransformation);setPixmap(pix);
}int SuperSlider::alt_value()
{return alt_handle->value();
}void SuperSlider::alt_setValue(int value)
{alt_handle->setValue(value);
}void SuperSlider::mouseReleaseEvent(QMouseEvent *mouseEvent)
{if (mouseEvent->button() == Qt::LeftButton){alt_handle->show();alt_handle->handleActivated = false;}mouseEvent->accept();
}void SuperSlider::alt_update()
{QPoint posCursor(QCursor::pos());QPoint posParent(mapToParent(mapToGlobal(pos())));QPoint point(alt_handle->mapToParent(alt_handle->mapFromGlobal(QCursor::pos())).x(),alt_handle->y());int horBuffer = (alt_handle->width());bool lessThanMax = mapToParent(point).x() < pos().x()+ width() - horBuffer;bool greaterThanMin = mapToParent(point).x() > pos().x();if(lessThanMax && greaterThanMin)alt_handle->move(point);emit alt_valueChanged(alt_value());
}void SuperSliderHandle::mousePressEvent(QMouseEvent *mouseEvent)
{qGuiApp->installEventFilter(filter);parent->clearFocus();
}bool SuperEventFilter::eventFilter(QObject* obj, QEvent* event)
{switch(event->type()){case QEvent::MouseButtonRelease:qGuiApp->removeEventFilter(this);return true;break;case QEvent::MouseMove:grandParent->alt_update();return true;break;default:return QObject::eventFilter(obj, event);}return false;
}void SuperSliderHandle::setValue(double value)
{double width = parent->width(), position = pos().x();double range = parent->maximum() - parent->minimum();int location = (value - parent->minimum())/range;location = location *width;move(y(),location);
}int SuperSliderHandle::value()
{double width = parent->width(), position = pos().x();double value = position/width;double range = parent->maximum() - parent->minimum();return parent->minimum() + (value * range);
}
void SuperSlider::Reset()
{int horBuffer = (alt_handle->width());QPoint myPos = mapToGlobal(pos());QPoint point(myPos.x() + width() - horBuffer, myPos.y()- alt_handle->height());point = alt_handle->mapFromParent(point);alt_handle->move(point);alt_handle->show();alt_handle->raise();}

3.继承QWidget与1有点异曲同工之处（也是自绘）

#pragma once#include 
#include 
#include 
#include 
#include  
#include "ui_CNW24GDoubleSlider.h"class DoubleSlider;class CNW24GDoubleSlider : public QWidget
{Q_OBJECTpublic:CNW24GDoubleSlider(QWidget *parent = nullptr);~CNW24GDoubleSlider();private:DoubleSlider* m_pDoubleSlider = nullptr;
private:Ui::CNW24GDoubleSliderClass ui;
};class DoubleSlider : public QWidget
{Q_OBJECT
public:DoubleSlider(QWidget* parent = 0);void setRange(float min, float max);void setSingleStep(float step);enum State { MinHandle, MaxHandle, None };float minValue() const;float maxValue() const;float minRange() const;float maxRange() const;void SetPressValue(float fpos);void SetValue(int npos);public slots:void setLabel(const QString& label);void setMaxValue(float val);void setMinValue(float val);signals:void minValueChanged(float);void maxValueChanged(float);private:float m_min;float m_max;float m_singleStep;float m_minValue;float m_maxValue;QRect minHandleRegion;QRect maxHandleRegion;State m_state;QString m_label;protected:void paintEvent(QPaintEvent* event);void paintColoredRect(QRect rect, QColor color, QPainter* painter);void paintValueLabel(QPainter* painter);void mousePressEvent(QMouseEvent* event);void mouseMoveEvent(QMouseEvent* event);void keyPressEvent(QKeyEvent* event);void leaveEvent(QEvent* event);};

#include "CNW24GDoubleSlider.h"CNW24GDoubleSlider::CNW24GDoubleSlider(QWidget *parent): QWidget(parent)
{ui.setupUi(this);ui.nameLabel->setText(u8"亮度");ui.nameLabel->setStyleSheet("width: 54px;height: 20px;color: #FFFFFF; background-color:none;");m_pDoubleSlider = new DoubleSlider(this);m_pDoubleSlider->move(30, 50);
}CNW24GDoubleSlider::~CNW24GDoubleSlider()
{
}/// 

/// DoubleSlider
/// 
/// 
DoubleSlider::DoubleSlider(QWidget* parent): QWidget(parent), m_min(0.0f), m_max(100.0f), m_singleStep(0.1f), m_minValue(0.0f), m_maxValue(100.0f), m_state(None)
{setFixedWidth(200);setFixedHeight(550);setFocusPolicy(Qt::StrongFocus);}void DoubleSlider::paintEvent(QPaintEvent* event)
{QWidget::paintEvent(event);QPainter painter(this);paintValueLabel(&painter);
}void DoubleSlider::paintColoredRect(QRect rect, QColor color, QPainter* painter)
{painter->fillRect(rect, QBrush(color));
}void DoubleSlider::paintValueLabel(QPainter* painter)
{// painter->setBrush(Qt::NoBrush);painter->setBrush(Qt::NoBrush);painter->setPen(Qt::white);painter->setFont(QFont("Arial", 12));QString minValueString = QString::number(m_minValue, 'f', 0);QString maxValueString = QString::number(m_maxValue, 'f', 0);QFontMetrics metrics = painter->fontMetrics();int mintextWidth = metrics.width(minValueString);int maxtextWidth = metrics.width(maxValueString);int textHeight = metrics.height();//---- paint textpainter->drawText(QRectF(2, 4, mintextWidth, textHeight), minValueString);painter->drawText(QRectF(width() - maxtextWidth - 2, 4, maxtextWidth, textHeight), maxValueString);//----- paint label textpainter->setFont(QFont("Arial", 12));metrics = painter->fontMetrics();int labelWidth = metrics.width(m_label);int labelHeight = metrics.height();QRectF textRect = QRectF((width() / 2 - labelWidth / 2), 0, labelWidth, labelHeight);painter->drawText(textRect, m_label);// endint minPos = (m_minValue - m_min) * width() / (m_max - m_min);int maxPos = (m_maxValue - m_min) * width() / (m_max - m_min);if (minPos <= 4) {minPos = 4;}else if (minPos >= width() - 8) {minPos = width() - 8;}else {}if (maxPos <= 4) {maxPos = 4;}else if (maxPos >= width() - 8) {maxPos = width() - 8;}else {}//----- paint groove//滑块槽paintColoredRect(QRect(4, 37, width() - 8, 2), Qt::yellow, painter);//滑块内槽paintColoredRect(QRect(minPos + 4, 37, maxPos - minPos, 2), QColor(51, 153, 155), painter);//----- handleminHandleRegion = QRect(minPos, 30, 8, 16);maxHandleRegion = QRect(maxPos, 30, 8, 16);//-----paint HandleQColor minColor = (m_state == MinHandle) ? QColor(51, 153, 155) : Qt::darkGray;QColor maxColor = (m_state == MaxHandle) ? QColor(51, 153, 155) : Qt::darkGray;paintColoredRect(minHandleRegion, minColor, painter); //左侧滑块paintColoredRect(maxHandleRegion, maxColor, painter); //右侧滑块
}inline float getValidValue(float val, float min, float max)
{float tmp = std::max(val, min);return std::min(tmp, max);
}void DoubleSlider::setRange(float min, float max)
{m_min = min;m_max = max;if (minValue() < m_min)setMinValue(m_min);if (maxValue() > m_max) {setMaxValue(m_max);}
}void DoubleSlider::setSingleStep(float step)
{m_singleStep = step;
}float DoubleSlider::minValue() const
{return m_minValue;
}
void DoubleSlider::setMinValue(float val)
{if (fabs(m_minValue - val) > 0.0001) {m_minValue = val;//emit minValueChanged(val);}
}float DoubleSlider::maxValue() const
{return m_maxValue;
}
void DoubleSlider::setMaxValue(float val)
{if (fabs(m_maxValue - val) > 0.0001) {m_maxValue = val;//emit maxValueChanged(val);}
}void DoubleSlider::setLabel(const QString& label)
{m_label = label;update();
}void DoubleSlider::leaveEvent(QEvent* event)
{QWidget::leaveEvent(event);m_state = None;update();
}float DoubleSlider::minRange() const
{return m_min;
}
float DoubleSlider::maxRange() const
{return m_max;
}void DoubleSlider::mousePressEvent(QMouseEvent* event)
{if (minHandleRegion.contains(event->pos())) {m_state = MinHandle;}else if (maxHandleRegion.contains(event->pos())) {m_state = MaxHandle;}else {SetPressValue(event->x());m_state = None;}if (fabs(minValue() - maxValue()) < 0.001) {if (fabs(minValue() - m_min) < 0.001) {m_state = MaxHandle;}else if (fabs(minValue() - m_max) < 0.001) {m_state = MinHandle;}else {}}update();
}
void DoubleSlider::SetPressValue(float fpos)
{float move = fpos * (m_max - m_min) * 1.0 / width() + m_min;abs(m_minValue - move) > abs(m_maxValue - move) ? m_state = MaxHandle : m_state = MinHandle;if (MaxHandle == m_state){float val = getValidValue(move, minValue(), m_max);setMaxValue(val);}else{float val = getValidValue(move, m_min, maxValue());setMinValue(val);}}void DoubleSlider::SetValue(int npos)
{float val = getValidValue(npos, m_min, maxValue());setMinValue(val);
}void DoubleSlider::mouseMoveEvent(QMouseEvent* event)
{if (event->buttons() & Qt::LeftButton) {float move = event->x() * (m_max - m_min) * 1.0 / width() + m_min;switch (m_state) {case MinHandle: {float val = getValidValue(move, m_min, maxValue());setMinValue(val);break;}case MaxHandle: {float val = getValidValue(move, minValue(), m_max);setMaxValue(val);break;}case None:default: break;}}update();
}void DoubleSlider::keyPressEvent(QKeyEvent* event)
{QWidget::keyPressEvent(event);if (event->key() == Qt::Key_Left) {if (m_state == MinHandle) {float val = getValidValue(minValue() - m_singleStep, m_min, maxValue());setMinValue(val);}else if (m_state == MaxHandle) {float val = getValidValue(maxValue() - m_singleStep, minValue(), m_max);setMaxValue(val);}else {}}else if (event->key() == Qt::Key_Right) {if (m_state == MinHandle) {float val = getValidValue(minValue() + m_singleStep, m_min, maxValue());setMinValue(val);}else if (m_state == MaxHandle) {float val = getValidValue(maxValue() + m_singleStep, minValue(), m_max);setMaxValue(val);}else {}}update();}

4.使用小聪明，但是可以使用Qt样式

晚点在更新，有事情忙