#include <qevent.h> #include <qwt_plot.h> #include <qwt_scale_widget.h> #include "scalepicker.h" ScalePicker::ScalePicker(QwtPlot *plot): QObject(plot) { for ( uint i = 0; i < QwtPlot::axisCnt; i++ ) { QwtScaleWidget *scaleWidget = (QwtScaleWidget *)plot->axisWidget(i); if ( scaleWidget ) scaleWidget->installEventFilter(this); } } bool ScalePicker::eventFilter(QObject *object, QEvent *e) { if ( object->inherits("QwtScaleWidget") && e->type() == QEvent::MouseButtonPress ) { mouseClicked((const QwtScaleWidget *)object, ((QMouseEvent *)e)->pos()); return true; } return QObject::eventFilter(object, e); } void ScalePicker::mouseClicked(const QwtScaleWidget *scale, const QPoint &pos) { QRect rect = scaleRect(scale); int margin = 10; // 10 pixels tolerance rect.setRect(rect.x() - margin, rect.y() - margin, rect.width() + 2 * margin, rect.height() + 2 * margin); if ( rect.contains(pos) ) // No click on the title { // translate the position in a value on the scale double value = 0.0; int axis = -1; const QwtScaleDraw *sd = scale->scaleDraw(); switch(scale->alignment()) { case QwtScaleDraw::LeftScale: { value = sd->scaleMap().invTransform(pos.y()); axis = QwtPlot::yLeft; break; } case QwtScaleDraw::RightScale: { value = sd->scaleMap().invTransform(pos.y()); axis = QwtPlot::yRight; break; } case QwtScaleDraw::BottomScale: { value = sd->scaleMap().invTransform(pos.x()); axis = QwtPlot::xBottom; break; } case QwtScaleDraw::TopScale: { value = sd->scaleMap().invTransform(pos.x()); axis = QwtPlot::xTop; break; } } Q_EMIT clicked(axis, value); } } // The rect of a scale without the title QRect ScalePicker::scaleRect(const QwtScaleWidget *scale) const { const int bld = scale->margin(); const int mjt = scale->scaleDraw()->maxTickLength(); const int sbd = scale->startBorderDist(); const int ebd = scale->endBorderDist(); QRect rect; switch(scale->alignment()) { case QwtScaleDraw::LeftScale: { rect.setRect(scale->width() - bld - mjt, sbd, mjt, scale->height() - sbd - ebd); break; } case QwtScaleDraw::RightScale: { rect.setRect(bld, sbd, mjt, scale->height() - sbd - ebd); break; } case QwtScaleDraw::BottomScale: { rect.setRect(sbd, bld, scale->width() - sbd - ebd, mjt); break; } case QwtScaleDraw::TopScale: { rect.setRect(sbd, scale->height() - bld - mjt, scale->width() - sbd - ebd, mjt); break; } } return rect; }