Qt绘制指南针（仪表盘绘制封装使用示例）

#include "qcgaugewidget.h" QcGaugeWidget::QcGaugeWidget(QWidget *parent) : QWidget(parent) { setMinimumSize(250,250); } QcBackgroundItem *QcGaugeWidget::addBackground(float position) { QcBackgroundItem * item = new QcBackgroundItem(this); item->setPosition(position); mItems.append(item); return item; } QcDegreesItem *QcGaugeWidget::addDegrees(float position) { QcDegreesItem * item = new QcDegreesItem(this); item->setPosition(position); mItems.append(item); return item; } QcValuesItem *QcGaugeWidget::addValues(float position) { QcValuesItem * item = new QcValuesItem(this); item->setPosition(position); mItems.append(item); return item; } QcArcItem *QcGaugeWidget::addArc(float position) { QcArcItem * item = new QcArcItem(this); item->setPosition(position); mItems.append(item); return item; } QcColorBand *QcGaugeWidget::addColorBand(float position) { QcColorBand * item = new QcColorBand(this); item->setPosition(position); mItems.append(item); return item; } QcNeedleItem *QcGaugeWidget::addNeedle(float position) { QcNeedleItem * item = new QcNeedleItem(this); item->setPosition(position); mItems.append(item); return item; } QcLabelItem *QcGaugeWidget::addLabel(float position) { QcLabelItem * item = new QcLabelItem(this); item->setPosition(position); mItems.append(item); return item; } QcGlassItem *QcGaugeWidget::addGlass(float position) { QcGlassItem * item = new QcGlassItem(this); item->setPosition(position); mItems.append(item); return item; } QcAttitudeMeter *QcGaugeWidget::addAttitudeMeter(float position) { QcAttitudeMeter * item = new QcAttitudeMeter(this); item->setPosition(position); mItems.append(item); return item; } void QcGaugeWidget::addItem(QcItem *item,float position) { // takes parentship of the item item->setParent(this); item->setPosition(position); mItems.append(item); } int QcGaugeWidget::removeItem(QcItem *item) { return mItems.removeAll(item); } QList QcGaugeWidget::items() { return mItems; } void QcGaugeWidget::paintEvent(QPaintEvent */*paintEvt*/) { QPainter painter(this); painter.setRenderHint(QPainter::Antialiasing); foreach (QcItem * item, mItems) { item->draw(&painter); } } /////////////////////////////////////////////////////////////////////////////////////////// QcItem::QcItem(QObject *parent) : QObject(parent) { parentWidget = qobject_cast(parent); mPosition = 50; } int QcItem::type() { return 50; } void QcItem::update() { parentWidget->update(); } float QcItem::position() { return mPosition; } QRectF QcItem::rect() { return mRect; } void QcItem::setPosition(float position) { if(position>100) mPosition = 100; else if(position<0) mPosition = 0; else mPosition = position; update(); } QRectF QcItem::adjustRect(float percentage) { float r = getRadius(mRect); float offset = r-(percentage*r)/100.0; QRectF tmpRect = mRect.adjusted(offset,offset,-offset,-offset); return tmpRect; } float QcItem::getRadius(const QRectF &tmpRect) { float r = 0; if(tmpRect.width()rect(); float r = getRadius(mRect); mRect.setWidth(2.0*r); mRect.setHeight(2.0*r); mRect.moveCenter(parentWidget->rect().center()); return mRect; } QPointF QcItem::getPoint(float deg,const QRectF &tmpRect) { float r = getRadius(tmpRect); float xx=cos(qDegreesToRadians(deg))*r; float yy=sin(qDegreesToRadians(deg))*r; QPointF pt; xx=tmpRect.center().x()-xx; yy=tmpRect.center().y()-yy; pt.setX(xx); pt.setY(yy); return pt; } float QcItem::getAngle(const QPointF&pt, const QRectF &tmpRect) { float xx=tmpRect.center().x()-pt.x(); float yy=tmpRect.center().y()-pt.y(); return qRadiansToDegrees( atan2(yy,xx)); } /////////////////////////////////////////////////////////////////////////////////////////// QcScaleItem::QcScaleItem(QObject *parent) : QcItem(parent) { mMinDegree = -45; mMaxDegree = 225; mMinValue = 0; mMaxValue = 100; } void QcScaleItem::setValueRange(float minValue, float maxValue) { if(!(minValuemMaxValue) throw (InvalidValueRange); mMinValue = minValue; update(); } void QcScaleItem::setMaxValue(float maxValue) { if(maxValuemMaxDegree) throw (InvalidDegreeRange); mMinDegree = minDegree; update(); } void QcScaleItem::setMaxDegree(float maxDegree) { if(maxDegreesetBrush(Qt::NoBrush); QLinearGradient linearGrad(tmpRect.topLeft(), tmpRect.bottomRight()); for(int i = 0;isetPen(mPen); painter->setBrush(linearGrad); painter->drawEllipse(adjustRect(position())); } void QcBackgroundItem::addColor(float position, const QColor &color) { if(position<0||position>1) return; QPair pair; pair.first = position; pair.second = color; mColors.append(pair); update(); } void QcBackgroundItem::clearrColors() { mColors.clear(); } /////////////////////////////////////////////////////////////////////////////////////////// QcGlassItem::QcGlassItem(QObject *parent) : QcItem(parent) { setPosition(88); } void QcGlassItem::draw(QPainter *painter) { resetRect(); QRectF tmpRect1 = adjustRect(position()); QRectF tmpRect2 = tmpRect1; float r = getRadius(tmpRect1); tmpRect2.setHeight(r/2.0); painter->setPen(Qt::NoPen); QColor clr1 = Qt::gray ; QColor clr2 = Qt::white; clr1.setAlphaF(0.2); clr2.setAlphaF(0.4); QLinearGradient linearGrad1(tmpRect1.topLeft(), tmpRect1.bottomRight()); linearGrad1.setColorAt(0.1, clr1); linearGrad1.setColorAt(0.5, clr2); painter->setBrush(linearGrad1); painter->drawPie(tmpRect1,0,16*180); tmpRect2.moveCenter(rect().center()); painter->drawPie(tmpRect2,0,-16*180); } /////////////////////////////////////////////////////////////////////////////////////////// QcLabelItem::QcLabelItem(QObject *parent) : QcItem(parent) { setPosition(50); mAngle = 270; mText = "%"; mColor = Qt::black; } void QcLabelItem::draw(QPainter *painter) { resetRect(); QRectF tmpRect = adjustRect(position()); float r = getRadius(rect()); QFont font("Meiryo UI", r/10.0, QFont::Bold); painter->setFont(font); painter->setPen(QPen(mColor)); QPointF txtCenter = getPoint(mAngle,tmpRect); QFontMetrics fMetrics = painter->fo