QCustomPlot Discussion and Comments

Could I exchange KeyAxis and ValueAxisReturn to overview

I tried do this,Result is image spring;but i don‘t know how to draw a line vertically down;Can you give me some advice

You only need to set the corresponding axis as the keyaxis axis

     this->addGraph(this->xAxis, axis);//固定x1
     this->addGraph(this->yAxis,axis);//固定y1