Use a basic implementation of a DelegateChooser for compat with older Qt

The interface is taken from Qt/KDE, but the implementation is different, because the Qt implementation depends on some Qt internals.
2019-10-20 12:39:47 +02:00 · 2019-10-20 12:39:47 +02:00 · c37495fae2
commit c37495fae2
parent cff46d97a8
7 changed files with 299 additions and 45 deletions
--- a/src/timeline2/DelegateChooser.cpp
+++ b/src/timeline2/DelegateChooser.cpp
@ -0,0 +1,160 @@
+#include "DelegateChooser.h"
+
+#include "Logging.h"
+
+// uses private API, which moved between versions
+#include <QQmlEngine>
+#include <QtGlobal>
+#if QT_VERSION >= QT_VERSION_CHECK(5, 14, 0)
+#include <QtQmlModels/private/qqmladaptormodel_p.h>
+#else
+#include <QtQml/private/qqmladaptormodel_p.h>
+#endif
+
+QQmlComponent *
+DelegateChoice::delegate() const
+{
+	return delegate_;
+}
+
+void
+DelegateChoice::setDelegate(QQmlComponent *delegate)
+{
+        if (delegate != delegate_) {
+                delegate_ = delegate;
+                emit delegateChanged();
+                emit changed();
+        }
+}
+
+QVariant
+DelegateChoice::roleValue() const
+{
+        return roleValue_;
+}
+
+void
+DelegateChoice::setRoleValue(const QVariant &value)
+{
+        if (value != roleValue_) {
+                roleValue_ = value;
+                emit roleValueChanged();
+                emit changed();
+        }
+}
+
+QVariant
+DelegateChooser::roleValue() const
+{
+        return roleValue_;
+}
+
+void
+DelegateChooser::setRoleValue(const QVariant &value)
+{
+        if (value != roleValue_) {
+                roleValue_ = value;
+                recalcChild();
+                emit roleValueChanged();
+        }
+}
+
+QQmlListProperty<DelegateChoice>
+DelegateChooser::choices()
+{
+        return QQmlListProperty<DelegateChoice>(this,
+                                                this,
+                                                &DelegateChooser::appendChoice,
+                                                &DelegateChooser::choiceCount,
+                                                &DelegateChooser::choice,
+                                                &DelegateChooser::clearChoices);
+}
+
+QString
+DelegateChooser::role() const
+{
+        return role_;
+}
+
+void
+DelegateChooser::setRole(const QString &role)
+{
+        if (role != role_) {
+                role_ = role;
+                emit roleChanged();
+        }
+}
+
+QQmlComponent *
+DelegateChooser::delegate(QQmlAdaptorModel *adaptorModel, int row, int column) const
+{
+        auto value = adaptorModel->value(adaptorModel->indexAt(row, column), role_);
+
+        for (const auto choice : choices_) {
+                auto choiceValue = choice->roleValue();
+                if (!value.isValid() || choiceValue == value) {
+                        nhlog::ui()->debug("Returned delegate for {}", role_.toStdString());
+                        return choice->delegate();
+                }
+        }
+
+        nhlog::ui()->debug("Returned null delegate");
+        return nullptr;
+}
+
+void
+DelegateChooser::appendChoice(QQmlListProperty<DelegateChoice> *p, DelegateChoice *c)
+{
+        DelegateChooser *dc = static_cast<DelegateChooser *>(p->object);
+        dc->choices_.append(c);
+        // dc->recalcChild();
+}
+
+int
+DelegateChooser::choiceCount(QQmlListProperty<DelegateChoice> *p)
+{
+        return static_cast<DelegateChooser *>(p->object)->choices_.count();
+}
+DelegateChoice *
+DelegateChooser::choice(QQmlListProperty<DelegateChoice> *p, int index)
+{
+        return static_cast<DelegateChooser *>(p->object)->choices_.at(index);
+}
+void
+DelegateChooser::clearChoices(QQmlListProperty<DelegateChoice> *p)
+{
+        static_cast<DelegateChooser *>(p->object)->choices_.clear();
+}
+
+void
+DelegateChooser::recalcChild()
+{
+        for (const auto choice : choices_) {
+                auto choiceValue = choice->roleValue();
+                if (!roleValue_.isValid() || !choiceValue.isValid() || choiceValue == roleValue_) {
+                        nhlog::ui()->debug("Returned delegate for {}", role_.toStdString());
+
+                        if (child) {
+                                // delete child;
+                                child = nullptr;
+                        }
+
+                        child = dynamic_cast<QQuickItem *>(
+                          choice->delegate()->create(QQmlEngine::contextForObject(this)));
+                        child->setParentItem(this);
+                        connect(this->child, &QQuickItem::heightChanged, this, [this]() {
+                                this->setHeight(this->child->height());
+                        });
+                        this->setHeight(this->child->height());
+                        return;
+                }
+        }
+}
+
+void
+DelegateChooser::componentComplete()
+{
+        QQuickItem::componentComplete();
+        recalcChild();
+}
+