Create Setting Panel

What are you configuring?
  QwtPlotItem (curve, bar, grid)?
    → Scenario A: ChartItem Panel (inherit DAChartItemSettingPanel)
  Arbitrary object (node, custom data model)?
    → Scenario B: Standalone Panel (inherit QWidget + DAPropertyPanelWidget)
  Application-level config (preferences, options)?
    → Scenario C: App Setting Page (inherit DAAbstractSettingPage)

class MyPanel : public DAChartItemSettingPanel {
    Q_OBJECT
public:
    enum PropertyID { PID_Title = 1, PID_Color = 2, PID_LineWidth = 3 };
    explicit MyPanel(QWidget* parent = nullptr);
    void updateUI(QwtPlotItem* item) override;
protected:
    void buildPropertyPanel() override;
private Q_SLOTS:
    void onPropertyValueChanged(int propertyId);
};

MyPanel::MyPanel(QWidget* parent) : DAChartItemSettingPanel(parent) {
    connect(this, &DAChartItemSettingPanel::propertyValueChanged,
            this, &MyPanel::onPropertyValueChanged);
    buildPropertyPanel();
}

void MyPanel::buildPropertyPanel() {
    auto* pp = propertyPanel();
    // Collapsible group for appearance properties
    pp->addCollapsibleGroup(tr("Appearance"));
    pp->addStringProperty(PID_Title, tr("Title"));
    pp->addColorProperty(PID_Color, tr("Color"));
    pp->addIntProperty(PID_LineWidth, tr("Line Width"), 1, 1, 100);
    pp->endGroup();
}

class DANodePropertyPanel : public QWidget {
    Q_OBJECT
public:
    enum PropertyId { PID_Name = 1, PID_Color = 2 };
    explicit DANodePropertyPanel(QWidget* parent = nullptr);
    void setTarget(DAWorkFlowNode* node);
protected Q_SLOTS:
    void buildPropertyPanel();
    void onPanelPropertyValueChanged(int propertyId);
    void onPropertyValueChanged(int propertyId);
Q_SIGNALS:
    void propertyValueChanged(int propertyId);
};

// Constructor: wire BOTH signal links
DANodePropertyPanel::DANodePropertyPanel(QWidget* parent)
    : QWidget(parent) {
    mPanel = new DAPropertyPanelWidget(this);
    // Link 1: panel → forwarding slot
    connect(mPanel, &DAPropertyPanelWidget::propertyValueChanged,
            this, &DANodePropertyPanel::onPanelPropertyValueChanged);
    // Link 2: self → handler slot (P0: often forgotten)
    connect(this, &DANodePropertyPanel::propertyValueChanged,
            this, &DANodePropertyPanel::onPropertyValueChanged);
    buildPropertyPanel();
}

void DANodePropertyPanel::buildPropertyPanel() {
    // Collapsible group for node info
    mPanel->addCollapsibleGroup(tr("Node Info"));
    mPanel->addStringProperty(PID_Name, tr("Name"));
    mPanel->addColorProperty(PID_Color, tr("Color"));
    mPanel->endGroup();
}

void MyPanel::buildPropertyPanel() {
    auto* pp = propertyPanel();

    // Root-level group
    pp->addCollapsibleGroup(tr("General"));
    pp->addStringProperty(PID_Title, tr("Title"));
    pp->endGroup();

    // Nested sub-panel with its own property IDs
    auto* subPanel = pp->addSubPanel(SID_AxisSettings, tr("Axis Settings"));
    subPanel->addCollapsibleGroup(tr("X Axis"));
    subPanel->addDoubleProperty(PID_XMin, tr("Min"), 0.0);
    subPanel->addDoubleProperty(PID_XMax, tr("Max"), 100.0);
    subPanel->endGroup();

    subPanel->addCollapsibleGroup(tr("Y Axis"));
    subPanel->addDoubleProperty(PID_YMin, tr("Min"), 0.0);
    subPanel->addDoubleProperty(PID_YMax, tr("Max"), 100.0);
    subPanel->endGroup();
    // No extra signal wiring needed — sub-panel propertyValueChanged
    // bubbles up to parent panel automatically
}

// Access sub-panel later for state updates:
void MyPanel::updateUI() {
    auto* subPanel = mPanel->getSubPanel(SID_AxisSettings);
    QSignalBlocker blocker(subPanel);
    subPanel->setDoubleValue(PID_XMin, ...);
    // ...
}

// Container delegates all DAPropertyPanelWidget methods:
DAPropertyPanelContainerWidget* container = new DAPropertyPanelContainerWidget(this);
container->addCollapsibleGroup(tr("Settings"));
container->addStringProperty(PID_Name, tr("Name"));
container->endGroup();
connect(container, &DAPropertyPanelContainerWidget::propertyValueChanged, ...);