core/objectrepeater: add ObjectRepeater

src/core/CMakeLists.txt

@@ -29,6 +29,7 @@ qt_add_library(quickshell-core STATIC
 	model.cpp
 	elapsedtimer.cpp
 	desktopentry.cpp
+	objectrepeater.cpp
 )
 
 set_source_files_properties(main.cpp PROPERTIES COMPILE_DEFINITIONS GIT_REVISION="${GIT_REVISION}")

src/core/module.md

@@ -21,5 +21,6 @@ headers = [
 	"model.hpp",
 	"elapsedtimer.hpp",
 	"desktopentry.hpp",
+	"objectrepeater.hpp",
 ]
 -----

src/core/objectrepeater.cpp

@@ -0,0 +1,191 @@
+#include "objectrepeater.hpp"
+#include <utility>
+
+#include <qabstractitemmodel.h>
+#include <qcontainerfwd.h>
+#include <qhash.h>
+#include <qlogging.h>
+#include <qobject.h>
+#include <qqmlcomponent.h>
+#include <qqmlcontext.h>
+#include <qqmlengine.h>
+#include <qqmllist.h>
+#include <qtmetamacros.h>
+#include <qtypes.h>
+#include <qvariant.h>
+
+QVariant ObjectRepeater::model() const { return this->mModel; }
+
+void ObjectRepeater::setModel(QVariant model) {
+	if (model == this->mModel) return;
+
+	if (this->itemModel != nullptr) {
+		QObject::disconnect(this->itemModel, nullptr, this, nullptr);
+	}
+
+	this->mModel = std::move(model);
+	emit this->modelChanged();
+	this->reloadElements();
+}
+
+void ObjectRepeater::onModelDestroyed() {
+	this->mModel.clear();
+	this->itemModel = nullptr;
+	emit this->modelChanged();
+	this->reloadElements();
+}
+
+QQmlComponent* ObjectRepeater::delegate() const { return this->mDelegate; }
+
+void ObjectRepeater::setDelegate(QQmlComponent* delegate) {
+	if (delegate == this->mDelegate) return;
+
+	if (this->mDelegate != nullptr) {
+		QObject::disconnect(this->mDelegate, nullptr, this, nullptr);
+	}
+
+	this->mDelegate = delegate;
+
+	if (delegate != nullptr) {
+		QObject::connect(
+		    this->mDelegate,
+		    &QObject::destroyed,
+		    this,
+		    &ObjectRepeater::onDelegateDestroyed
+		);
+	}
+
+	emit this->delegateChanged();
+	this->reloadElements();
+}
+
+void ObjectRepeater::onDelegateDestroyed() {
+	this->mDelegate = nullptr;
+	emit this->delegateChanged();
+	this->reloadElements();
+}
+
+void ObjectRepeater::reloadElements() {
+	for (auto i = this->valuesList.length() - 1; i >= 0; i--) {
+		this->removeComponent(i);
+	}
+
+	if (this->mDelegate == nullptr || !this->mModel.isValid()) return;
+
+	if (this->mModel.canConvert<QAbstractItemModel*>()) {
+		auto* model = this->mModel.value<QAbstractItemModel*>();
+		this->itemModel = model;
+
+		this->insertModelElements(model, 0, model->rowCount() - 1); // -1 is fine
+
+		// clang-format off
+		QObject::connect(model, &QObject::destroyed, this, &ObjectRepeater::onModelDestroyed);
+		QObject::connect(model, &QAbstractItemModel::rowsInserted, this, &ObjectRepeater::onModelRowsInserted);
+		QObject::connect(model, &QAbstractItemModel::rowsAboutToBeRemoved, this, &ObjectRepeater::onModelRowsAboutToBeRemoved);
+		QObject::connect(model, &QAbstractItemModel::rowsMoved, this, &ObjectRepeater::onModelRowsMoved);
+		QObject::connect(model, &QAbstractItemModel::modelAboutToBeReset, this, &ObjectRepeater::onModelAboutToBeReset);
+		// clang-format on
+	} else if (this->mModel.canConvert<QQmlListReference>()) {
+		auto values = this->mModel.value<QQmlListReference>();
+		auto len = values.count();
+
+		for (auto i = 0; i != len; i++) {
+			this->insertComponent(i, {{"modelData", QVariant::fromValue(values.at(i))}});
+		}
+	} else if (this->mModel.canConvert<QVector<QVariant>>()) {
+		auto values = this->mModel.value<QVector<QVariant>>();
+
+		for (auto& value: values) {
+			this->insertComponent(this->valuesList.length(), {{"modelData", value}});
+		}
+	} else {
+		qCritical() << this
+		            << "Cannot create components as the model is not compatible:" << this->mModel;
+	}
+}
+
+void ObjectRepeater::insertModelElements(QAbstractItemModel* model, int first, int last) {
+	auto roles = model->roleNames();
+	auto roleDataVec = QVector<QModelRoleData>();
+	for (auto id: roles.keys()) {
+		roleDataVec.push_back(QModelRoleData(id));
+	}
+
+	auto values = QModelRoleDataSpan(roleDataVec);
+	auto props = QVariantMap();
+
+	for (auto i = first; i != last + 1; i++) {
+		auto index = model->index(i, 0);
+		model->multiData(index, values);
+
+		for (auto [id, name]: roles.asKeyValueRange()) {
+			props.insert(name, *values.dataForRole(id));
+		}
+
+		this->insertComponent(i, props);
+
+		props.clear();
+	}
+}
+
+void ObjectRepeater::onModelRowsInserted(const QModelIndex& parent, int first, int last) {
+	if (parent != QModelIndex()) return;
+
+	this->insertModelElements(this->itemModel, first, last);
+}
+
+void ObjectRepeater::onModelRowsAboutToBeRemoved(const QModelIndex& parent, int first, int last) {
+	if (parent != QModelIndex()) return;
+
+	for (auto i = last; i != first - 1; i--) {
+		this->removeComponent(i);
+	}
+}
+
+void ObjectRepeater::onModelRowsMoved(
+    const QModelIndex& sourceParent,
+    int sourceStart,
+    int sourceEnd,
+    const QModelIndex& destParent,
+    int destStart
+) {
+	auto hasSource = sourceParent != QModelIndex();
+	auto hasDest = destParent != QModelIndex();
+
+	if (!hasSource && !hasDest) return;
+
+	if (hasSource) {
+		this->onModelRowsAboutToBeRemoved(sourceParent, sourceStart, sourceEnd);
+	}
+
+	if (hasDest) {
+		this->onModelRowsInserted(destParent, destStart, destStart + (sourceEnd - sourceStart));
+	}
+}
+
+void ObjectRepeater::onModelAboutToBeReset() {
+	auto last = static_cast<int>(this->valuesList.length() - 1);
+	this->onModelRowsAboutToBeRemoved(QModelIndex(), 0, last); // -1 is fine
+}
+
+void ObjectRepeater::insertComponent(qsizetype index, const QVariantMap& properties) {
+	auto* context = QQmlEngine::contextForObject(this);
+	auto* instance = this->mDelegate->createWithInitialProperties(properties, context);
+
+	if (instance == nullptr) {
+		qWarning().noquote() << this->mDelegate->errorString();
+		qWarning() << this << "failed to create object for model data" << properties;
+	} else {
+		QQmlEngine::setObjectOwnership(instance, QQmlEngine::CppOwnership);
+		instance->setParent(this);
+	}
+
+	this->insertObject(instance, index);
+}
+
+void ObjectRepeater::removeComponent(qsizetype index) {
+	auto* instance = this->valuesList.at(index);
+	delete instance;
+
+	this->removeAt(index);
+}

src/core/objectrepeater.hpp

@@ -0,0 +1,86 @@
+#pragma once
+
+#include <qabstractitemmodel.h>
+#include <qobject.h>
+#include <qqmlcomponent.h>
+#include <qqmlintegration.h>
+#include <qtmetamacros.h>
+#include <qtypes.h>
+#include <qvariant.h>
+
+#include "model.hpp"
+
+///! A Repeater / for loop / map for non Item derived objects.
+/// The ObjectRepeater creates instances of the provided delegate for every entry in the
+/// given model, similarly to a [Repeater] but for non visual types.
+///
+/// [Repeater]: https://doc.qt.io/qt-6/qml-qtquick-repeater.html
+class ObjectRepeater: public ObjectModel<QObject> {
+	Q_OBJECT;
+	/// The model providing data to the ObjectRepeater.
+	///
+	/// Currently accepted model types are QML `list<T>` lists, javascript arrays,
+	/// and [QAbstractListModel] derived models, though only one column will be repeated
+	/// from the latter.
+	///
+	/// Note: [ObjectModel] is a [QAbstractListModel] with a single column.
+	///
+	/// [QAbstractListModel]: https://doc.qt.io/qt-6/qabstractlistmodel.html
+	/// [ObjectModel]: ../objectmodel
+	Q_PROPERTY(QVariant model READ model WRITE setModel NOTIFY modelChanged);
+	/// The delegate component to repeat.
+	///
+	/// The delegate is given the same properties as in a Repeater, except `index` which
+	/// is not currently implemented.
+	///
+	/// If the model is a `list<T>` or javascript array, a `modelData` property will be
+	/// exposed containing the entry from the model. If the model is a [QAbstractListModel],
+	/// the roles from the model will be exposed.
+	///
+	/// Note: [ObjectModel] has a single role named `modelData` for compatibility with normal lists.
+	///
+	/// [QAbstractListModel]: https://doc.qt.io/qt-6/qabstractlistmodel.html
+	/// [ObjectModel]: ../objectmodel
+	Q_PROPERTY(QQmlComponent* delegate READ delegate WRITE setDelegate NOTIFY delegateChanged);
+	Q_CLASSINFO("DefaultProperty", "delegate");
+	QML_ELEMENT;
+
+public:
+	explicit ObjectRepeater(QObject* parent = nullptr): ObjectModel(parent) {}
+
+	[[nodiscard]] QVariant model() const;
+	void setModel(QVariant model);
+
+	[[nodiscard]] QQmlComponent* delegate() const;
+	void setDelegate(QQmlComponent* delegate);
+
+signals:
+	void modelChanged();
+	void delegateChanged();
+
+private slots:
+	void onDelegateDestroyed();
+	void onModelDestroyed();
+	void onModelRowsInserted(const QModelIndex& parent, int first, int last);
+	void onModelRowsAboutToBeRemoved(const QModelIndex& parent, int first, int last);
+
+	void onModelRowsMoved(
+	    const QModelIndex& sourceParent,
+	    int sourceStart,
+	    int sourceEnd,
+	    const QModelIndex& destParent,
+	    int destStart
+	);
+
+	void onModelAboutToBeReset();
+
+private:
+	void reloadElements();
+	void insertModelElements(QAbstractItemModel* model, int first, int last);
+	void insertComponent(qsizetype index, const QVariantMap& properties);
+	void removeComponent(qsizetype index);
+
+	QVariant mModel;
+	QAbstractItemModel* itemModel = nullptr;
+	QQmlComponent* mDelegate = nullptr;
+};