diff -r 68988ebc2a68 -r 593a658cba8e src/mainwindow.cpp
--- a/src/mainwindow.cpp	Mon Sep 23 14:06:36 2019 +0300
+++ b/src/mainwindow.cpp	Thu Oct 03 11:45:44 2019 +0300
@@ -1,20 +1,107 @@
 #include "mainwindow.h"
 #include "ui_mainwindow.h"
 #include "version.h"
-#include <QQuaternion>
+#include <QLabel>
+#include <QVBoxLayout>
 
 MainWindow::MainWindow(QWidget *parent) :
 	QMainWindow{parent},
-	ui{std::make_unique<Ui_MainWindow>()}
+	ui{std::make_unique<Ui_MainWindow>()},
+	documents{this}
 {
 	ui->setupUi(this);
+	connect(ui->actionNew, &QAction::triggered, this, &MainWindow::newModel);
 	connect(ui->actionQuit, &QAction::triggered, this, &QMainWindow::close);
+	updateTitle();
+}
+
+MainWindow::~MainWindow()
+{
+}
+
+void MainWindow::newModel()
+{
+	documents.newModel();
+	this->updateTabs();
+}
+
+#include <QFileDialog>
+#include <QMessageBox>
+void MainWindow::openModel()
+{
+	const QString path = QFileDialog::getOpenFileName(
+		this, "Open model", "", "LDraw models (*.ldr *.dat)");
+	if (not path.isEmpty())
+	{
+		QFile file{path};
+		const bool open_result = file.open(QIODevice::ReadOnly);
+		if (open_result)
+		{
+
+		}
+		else
+		{
+			QMessageBox::critical(this, "Problem opening file",
+				QString{"Could not open %1: %2"}
+					.arg(path)
+					.arg(file.errorString()));
+		}
+	}
+}
+
+/**
+ * @brief Creates a new tab widget for the specified model.
+ * @param model Model to get a new tab widget for
+ * @return widget
+ */
+QWidget* MainWindow::createWidgetForModel(Model* model)
+{
+	Q_UNUSED(model);
+	QWidget* widget = new QWidget(ui->tabs);
+	QLabel* label = new QLabel("asdf", widget);
+	QVBoxLayout* layout = new QVBoxLayout;
+	layout->addWidget(label);
+	widget->setLayout(layout);
+	return widget;
+}
+
+/**
+ * @brief Gets a tab widget for the specified model. If it does not exist,
+ * it will be created.
+ * @param model Model to get a tab widget for
+ * @return widget
+ */
+QWidget* MainWindow::getWidgetForModel(Model* model)
+{
+	QWidget* widget = this->modelWidgets.value(model);
+	if (widget == nullptr)
+	{
+		QWidget* const new_widget = createWidgetForModel(model);
+		this->modelWidgets[model] = new_widget;
+		return new_widget;
+	}
+	else
+	{
+		return widget;
+	}
+}
+
+/**
+ * @brief Updates the tab widget
+ */
+void MainWindow::updateTabs()
+{
+
+}
+
+/**
+ * @brief Updates the title of the main window so to contain the app's name
+ * and version as well as the open document name.
+ */
+void MainWindow::updateTitle()
+{
 	QString title = ::appName;
 	title += " ";
 	title += fullVersionString();
 	setWindowTitle(title);
 }
-
-MainWindow::~MainWindow()
-{
-}