Hey there! I’ve worked through this exact scenario plenty of times, so let’s break down your questions step by step.

1. How to Insert QChartView in Qt Designer #

Qt Designer doesn’t include QChartView in the default widget box, but we can use the promote widget feature to add it easily:

• Drag a QWidget (or QFrame, whichever container you prefer) onto your form. Resize and position it to define where your chart will display—this acts as your chart’s placeholder.
• Right-click the QWidget, select Promote to... from the context menu.
• In the promotion dialog:
  • Enter QChartView in the Promoted class name field.
  • Enter QtCharts/QChartView in the Header file field.
  • Click Add, then hit Promote.
• Now your QWidget is treated as a QChartView at compile time. Don’t forget to add QT += charts to your .pro project file—this links the QtCharts module so your code compiles without errors.

2. Adding Code-Created QChart to Containers & Setting Display Area in Designer #

Setting the Display Area in Qt Designer #

The placeholder widget you dragged earlier is your chart’s display area. You can:

• Adjust its size and position directly by dragging in Designer.
• Use layouts (like Grid Layout or Vertical Layout) to make it automatically resize with the parent window. Just select the placeholder and its parent, then apply a layout from the toolbar.

Attaching Your Code-Created QChart #

There are two common approaches depending on whether you promoted the widget or not:

Option 1: Using the Promoted QChartView

If you followed step 1 above, your UI already has a QChartView object (e.g., ui->chartView). In your form’s constructor:

// Create and configure your QChart
QChart *myChart = new QChart();
QLineSeries *series = new QLineSeries();
series->append(0, 3);
series->append(1, 7);
series->append(2, 5);
myChart->addSeries(series);
myChart->createDefaultAxes();
myChart->setTitle("Sample Chart");

// Attach the chart to the promoted QChartView
ui->chartView->setChart(myChart);
// Enable anti-aliasing for smoother rendering
ui->chartView->setRenderHint(QPainter::Antialiasing);

Option 2: Using a Regular QWidget as Container

If you didn’t promote the widget, you can embed the QChartView directly into the container:

// Create your chart (same as above)
QChart *myChart = new QChart();
QLineSeries *series = new QLineSeries();
series->append(0, 3);
series->append(1, 7);
series->append(2, 5);
myChart->addSeries(series);
myChart->createDefaultAxes();

// Create QChartView and attach it to the container
QChartView *chartView = new QChartView(myChart, ui->chartContainer);
// Use a layout to make the chart fill the container and resize automatically
QVBoxLayout *layout = new QVBoxLayout(ui->chartContainer);
layout->setContentsMargins(0, 0, 0, 0); // Remove extra padding if needed
layout->addWidget(chartView);
ui->chartContainer->setLayout(layout);

// Enable anti-aliasing
chartView->setRenderHint(QPainter::Antialiasing);

Either way, the placeholder’s size and layout in Designer controls where the chart appears—no extra code needed to define the display area once you’ve set up the layout correctly.

内容的提问来源于stack exchange，提问作者Ufx