Re: Draw text on top of both canvas and plot background?

[Elvis S. <elv...@or...>]

Den tis 12 mars 2019 kl 09:13 skrev Elvis Stansvik
<elv...@or...>:
>
> Den tis 12 mars 2019 kl 09:09 skrev Uwe Rathmann <Uwe...@ti...>:
> >
> > Hi Elvis,
> >
> > > Hope that makes it more clear.
> >
> > That doesn't answer my question, but maybe all you want to do is:
>
> Hm, I'm confused. Your question was "Where exactly do you want to draw
> the extra text", to which I answered
>
> "The desired_result.png image shows where I want to paint the text
> "g/t". I added the text with an image editor. It's right below the top
> axis, right aligned with its max label."
>
> and attached a picture showing exactly where I want to draw the text.
>
> What more info do you need? :p
>
> Elvis
>
> >
> > class YourScaleDraw : public QwtScaleDraw
> > {
> >      ....
> >
> >      QwtText label( double value ) const override
> >      {
> >          auto txt = QLocale().toString( value );
> >
> >          const auto ticks = scaleDiv().ticks[ QwtScaleDiv::MajorTick ];
> >          if ( !ticks.empty() && value == ticks.last() )
> >          {
> >              txt += "\nUnit";
> >          }
> >
> >          return txt;
> >      }
> > };

The approach you showed here is very valuable though, because as a
backup plan, if it turns out it's not possible to paint the text where
I want it, is to do it like this (modifying, or possibly entirely
replacing one of the top axis labels), so thanks a lot for giving this
example on how to get out the major ticks et.c.

Elvis

> >
> > plot->setAxisScaleDraw( QwtPlot::xTop, new YourScaleDraw() );
>
> That will draw the text inside the top axis. I want to draw it below
> the top axis, straddling the canvas and plot background, as like my
> desired_result.png image shows.
>
> Elvis
>
> >
> > Uwe