更新代码

third/qcustomplotdemo/frmexample/frmquadratic.cpp

@@ -21,6 +21,7 @@ void frmQuadratic::initForm()
         x[i] = i / 50.0 - 1; // x goes from -1 to 1
         y[i] = x[i] * x[i]; // let's plot a quadratic function
     }
+
     // create graph and assign data to it:
     ui->customPlot->addGraph();
     ui->customPlot->graph(0)->setData(x, y);