different selection modes of QwtPlotPicker

Hello,

I'm using the QwtPlotPicker and I'm wondering whether it is possible to have both Point- and RectSelection modes simultanously. So that if I click one time on a QwtPlotItem/QwtPlotMarker then it is selected, but if I drag a rectangle to select more than one item, then all items within the dragged rectangle shall be selected.
Is this possible to do? If yes, tell me please how to achieve it.

Thank you

regards

I expected that the QwtPlotPicker can handle both the PointSelection and RectSeletion modes, so that if I click one time on an item then the SIGNAL selected(const QwtDoublePoint &pos) is called and if drag a rectangle around several items then the SIGNAL selected(const QwtDoubleRect &rect) would be called. Obviosly my expectations are not right, because I can only use one of this two selection modes. How shall be the QwtPlotPicker parameterized to fulfill my expectation? The following code does not do the right thing:

Code:

---

picker = new QwtPlotPicker(QwtPlot::xBottom, QwtPlot::yLeft,
    	    		QwtPicker::PointSelection | QwtPicker::RectSelection | QwtPicker::DragSelection,
				QwtPlotPicker::RectRubberBand, QwtPicker::AlwaysOn,
				this->canvas());
 
   // connect the signals coming from QwtPlotPicker with the member functions
    	    connect( picker, SIGNAL(moved(const QwtDoublePoint& ) ),
    	    		this, SLOT(cursorMoved( const QwtDoublePoint& ) ) );
 
    	    connect( picker, SIGNAL(selected( const QwtDoublePoint& ) ),
    	    		this, SLOT(cursorSelected( const QwtDoublePoint& ) ) );
 
    	    connect( picker, SIGNAL(selected (const QwtDoubleRect &) ),
    	       	    		this, SLOT(RectangleSelected( const QwtDoubleRect& ) ) );

---

Or is here another logical problem? Help me please.

Thank you

I'm using now the QwtPlotPicker in RectSelection, DragSelection mode:

Code:

---

// create QwtPlotPicker to allow user moving the points on the plot
 
    	    picker = new QwtPlotPicker(QwtPlot::xBottom, QwtPlot::yLeft,
    	    		QwtPicker::RectSelection | QwtPicker::DragSelection,
				QwtPlotPicker::RectRubberBand, QwtPicker::AlwaysOn,
				this->canvas());
 
   // connect the signals coming from QwtPlotPicker with the member functions
    	    connect( picker, SIGNAL(moved(const QwtDoublePoint& ) ),
    	    		this, SLOT(cursorMoved( const QwtDoublePoint& ) ) );
 
    	    connect( picker, SIGNAL(selected (const QwtDoubleRect &) ),
    	       	    		this, SLOT(RectangleSelected( const QwtDoubleRect& ) ) );

---

But it has unwished behaviour, if I drag the selected point, because during the dragging a selection rectangle is also painted. I would like to avoid it and just move the items, without drawing simulataneously the selection rectangle. It looks very strange. How can I achieve it? I tried to set another rubber band (NoRubberBand), after the selection, but how to reverse it, when the drag event is over?

Another idea: perhaps it is possible to set different mousepatterns for different actions? For example selection with left mouse and dragging with right mouse? Can the QwtPlotpicker interpret it?

another question: if I drag only one item, then in "cursorMoved" function I just set the mouseposition to the item's position and it works fine. If I select several items and want to drag them, then they get all the mouse position and appears at the same place. How can I implement such movement that the selected items only moves relatively to mouse direction and movement? Can you provide me a code snippet of it? I thought about storing the initial mouse click position and calculate the difference relatively to this initial point, but the "cursorMoved" function is called frequently while dragging so that this varaible would be overridden...

my code:

Code:

---

// this function provides the ability to select several items on the plot by dragging a rectangle around them
void Plot::RectangleSelected( const QwtDoubleRect& rect){
	std::cout << "in Plot::RectangleSelected" << std::endl;
	//============= clear the list with selected items, before start new selection
	  if(!selected_Points.empty()){
		while(!selected_Points.empty()){
			QwtPlotMarker *tempMark = selected_Points.back();
			const QwtSymbol symbol = tempMark->symbol();
			 QwtSymbol newSymbol = symbol;
			 newSymbol.setBrush(symbol.brush().color().light(150));	// turn back the highlighten symbol
			 tempMark->setSymbol(newSymbol);
			selected_Points.pop_back();		// delete the selected items from the list
		}
	}
	  //============= end of clear the list
 
	const QwtPlotItemList& List = itemList();		// get all items from the plot
		QwtPlotItemIterator Iter = List.begin();
 
		// get the two vertice of the selection rectangle
			QwtDoublePoint tl = rect.topLeft();
			QwtDoublePoint br = rect.bottomRight();
			std::cout << "recOfClick(x,y,width, height) ="  << rect.x()<<", " << rect.y() << ", " << rect.width()<< ", "<<rect.height()<< std::endl;
		 double TRtlX = this->transform(picker->xAxis(),tl.x());		// transform the rectangles coordinates to plot's coordinates
		 double TRtlY = this->transform(picker->yAxis(),tl.y());
		 double TRbrX = this->transform(picker->xAxis(),br.x());
		 double TRbrY= this->transform(picker->yAxis(),br.y());
		 QwtDoubleRect *trRect= new QwtDoubleRect(QRect(QPoint(TRtlX,TRtlY),QPoint(TRbrX,TRbrY)));	// build a rectangle with the new coordinates
		 std::cout << "recOfClick(x,y,width, height) ="  << trRect->x()<<", " << trRect->y() << ", " << trRect->width()<< ", "<<trRect->height()<< std::endl;
		 if( trRect->width()<5 && trRect->height()<5){ // if it was just a click and not drugged rectangle, then...
			 trRect->setHeight(20);		// ...generate a rectangle around the click's position
			 trRect->setWidth(20);
 
		 }
 
	  while(Iter != List.end())			// and iterate through them...
	  {
	     if((*Iter)->rtti() == QwtPlotItem::Rtti_PlotMarker){	// ... until you find the item from class QwtPLotMarker
	    	 QwtPlotMarker *mark = ((QwtPlotMarker*)(*Iter));
				 double x = this->transform(mark->xAxis(),mark->xValue());		// transform the item's coordinates to plot's coordinates
	    	     double y = this->transform(mark->yAxis(),mark->yValue());
	    	      	std::cout << "mark.xValue()=" << mark->xValue() << ", mark.yValue()=" << mark->yValue()<< std::endl;
	    	      	std::cout << "transformed mark coord = " << x << ", " << y<< std::endl;
	    	      	QwtDoublePoint trPoint = QwtDoublePoint(x,y);		// create a point consisting of transformed coordinates
 
 
	    	  if(trRect->contains(trPoint)){			// if click's rectangle includes the QwtPlotMarker, then...
	        	std::cout << "MATCH"  << std::endl;
 
				 //selectedPoint = mark;					// ... save the pointer to this item into variable "selectedPoint"
				 std::cout << "selectedPoint = " << mark << std::endl;
				 const QwtSymbol symbol = mark->symbol();
				 QwtSymbol newSymbol = symbol;
				 newSymbol.setBrush(symbol.brush().color().dark(150));	// highlighten the selected item by darken its color
				 mark->setSymbol(newSymbol);
	        	selected_Points.push_back(mark);
	        }
 
	     }
	     Iter++;
	  }
		 replot();
		 std::cout << "selected_Points.size()= " << selected_Points.size() << std::endl;
}
//##################################################################
// this function provides the ability to move items on the plot
void Plot::cursorMoved( const QwtDoublePoint& Point){
 
	std::cout << "in Plot::cursorMoved " <<  std::endl;
	std::cout << "Point.x()= " << Point.x() <<"Point.y()= " << Point.y() << std::endl;
	if(!selected_Points.empty()){		//if the list with selected items is not empty, then...
		for(unsigned i=0; i< selected_Points.size(); ++i) {
			 std::cout << "loop " << i << std::endl;
			selected_Points[i]->setValue(Point);	// set the new coordinates to the moved item
				    	}
		this->replot();	// replot the plot widget after the selected point was moved
	}
	replot();
}

---

So, I have managed to avoid drawing the selection rectangle while dragging objects by switching between NoRubberBand and RectRubberBand here:

Code:

---

void Plot::cursorMoved( const QwtDoublePoint& Point){
 
	std::cout << "in Plot::cursorMoved " <<  std::endl;
	std::cout << "Point.x()= " << Point.x() <<"Point.y()= " << Point.y() << std::endl;
	if(!selected_Points.empty()){		//if the list with selected items is not empty, then...
		for(int i=0; i< selected_Points.size(); ++i) {
			picker->setRubberBand(QwtPicker::NoRubberBand);
			 double delta_x = Point.x() - clickpos->x();	// calculate the x difference
			 double delta_y = Point.y() - clickpos->y();	// calculate the y difference
			selected_Points[i]->setValue(selected_Points[i]->xValue() + delta_x, selected_Points[i]->yValue() + delta_y);	// set the new coordinates to the moved item
			int index = (selected_Points[i]->title().text().toInt());	// transform from string to integer
			std::cout << "index = " << index<< std::endl;
			//mainFrame *mf = dynamic_cast<mainFrame*>(parentWidget());
			_mf->updateChromosome( selected_Points[i]->value(),index);	// update the individuals with new values
		}
		this->replot();	// replot the plot widget after the selected point was moved
	}
	else{
		picker->setRubberBand(QwtPicker::RectRubberBand);    // switch the RubberBand
	}
	clickpos = new QwtDoublePoint(Point);		// update the reference point
}

---

Hello again :)

I would like to differentiate between right and left mouse click while using QwtPlotPicker, so that the left mouse click do one action and the right click do another action (push back items in different vectors). How can I do it with QwtPlotPicker?

best regards,

Vitali