Reduce allocations and time spent creating delegates by half

This commit is contained in:
Nicolas Werner 2021-12-29 22:46:04 +01:00
parent 7cfb7dcea4
commit b847623fbe
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GPG key ID: C8D75E610773F2D9
2 changed files with 9 additions and 7 deletions

View file

@ -53,6 +53,7 @@ DelegateChooser::setRoleValue(const QVariant &value)
{ {
if (value != roleValue_) { if (value != roleValue_) {
roleValue_ = value; roleValue_ = value;
if (isComponentComplete())
recalcChild(); recalcChild();
emit roleValueChanged(); emit roleValueChanged();
} }
@ -96,8 +97,8 @@ void
DelegateChooser::recalcChild() DelegateChooser::recalcChild()
{ {
for (const auto choice : qAsConst(choices_)) { for (const auto choice : qAsConst(choices_)) {
auto choiceValue = choice->roleValue(); const auto &choiceValue = choice->roleValueRef();
if (!roleValue_.isValid() || !choiceValue.isValid() || choiceValue == roleValue_) { if (choiceValue == roleValue_ || (!choiceValue.isValid() && !roleValue_.isValid())) {
if (child_) { if (child_) {
child_->setParentItem(nullptr); child_->setParentItem(nullptr);
child_ = nullptr; child_ = nullptr;

View file

@ -25,10 +25,11 @@ public:
Q_PROPERTY(QVariant roleValue READ roleValue WRITE setRoleValue NOTIFY roleValueChanged) Q_PROPERTY(QVariant roleValue READ roleValue WRITE setRoleValue NOTIFY roleValueChanged)
Q_PROPERTY(QQmlComponent *delegate READ delegate WRITE setDelegate NOTIFY delegateChanged) Q_PROPERTY(QQmlComponent *delegate READ delegate WRITE setDelegate NOTIFY delegateChanged)
QQmlComponent *delegate() const; [[nodiscard]] QQmlComponent *delegate() const;
void setDelegate(QQmlComponent *delegate); void setDelegate(QQmlComponent *delegate);
QVariant roleValue() const; [[nodiscard]] QVariant roleValue() const;
[[nodiscard]] const QVariant &roleValueRef() const { return roleValue_; }
void setRoleValue(const QVariant &value); void setRoleValue(const QVariant &value);
signals: signals:
@ -53,10 +54,10 @@ public:
QQmlListProperty<DelegateChoice> choices(); QQmlListProperty<DelegateChoice> choices();
QVariant roleValue() const; [[nodiscard]] QVariant roleValue() const;
void setRoleValue(const QVariant &value); void setRoleValue(const QVariant &value);
QQuickItem *child() const { return child_; } [[nodiscard]] QQuickItem *child() const { return child_; }
void recalcChild(); void recalcChild();
void componentComplete() override; void componentComplete() override;