From cc9646457d64b0a74e59ef511c3ae3db345bdbe4 Mon Sep 17 00:00:00 2001
From: Soeren Apel <soeren@apelpie.net>
Date: Mon, 10 Oct 2016 09:15:04 +0200
Subject: [PATCH 1/1] MainWindow: Prevent the QTabWidget from collapsing when
 empty

---
 pv/mainwindow.cpp | 22 +++++++++++++++++-----
 pv/mainwindow.hpp |  1 +
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/pv/mainwindow.cpp b/pv/mainwindow.cpp
index 39ce7ed6..36f9b1a0 100644
--- a/pv/mainwindow.cpp
+++ b/pv/mainwindow.cpp
@@ -248,6 +248,8 @@ shared_ptr<Session> MainWindow::add_session()
 
 void MainWindow::remove_session(shared_ptr<Session> session)
 {
+	int h = new_session_button_->height();
+
 	for (shared_ptr<views::ViewBase> view : session->views()) {
 		// Find the dock the view is contained in and remove it
 		for (auto entry : view_docks_)
@@ -274,10 +276,21 @@ void MainWindow::remove_session(shared_ptr<Session> session)
 	sessions_.remove_if([&](shared_ptr<Session> s) {
 		return s == session; });
 
-	// Update the window title if there is no view left to
-	// generate focus change events
-	if (sessions_.empty())
+	if (sessions_.empty()) {
+		// When there are no more tabs, the height of the QTabWidget
+		// drops to zero. We must prevent this to keep the static
+		// widgets visible
+		for (QWidget *w : static_tab_widget_->findChildren<QWidget*>())
+			w->setMinimumHeight(h);
+
+		int margin = static_tab_widget_->layout()->contentsMargins().bottom();
+		static_tab_widget_->setMinimumHeight(h + 2 * margin);
+		session_selector_.setMinimumHeight(h + 2 * margin);
+
+		// Update the window title if there is no view left to
+		// generate focus change events
 		setWindowTitle(WindowTitle);
+	}
 }
 
 void MainWindow::setup_ui()
@@ -318,11 +331,10 @@ void MainWindow::setup_ui()
 	layout->setContentsMargins(2, 2, 2, 2);
 	layout->addWidget(new_session_button_);
 
-	QWidget* static_tab_widget_ = new QWidget();
+	static_tab_widget_ = new QWidget();
 	static_tab_widget_->setLayout(layout);
 
 	session_selector_.setCornerWidget(static_tab_widget_, Qt::TopLeftCorner);
-
 	session_selector_.setTabsClosable(true);
 
 	connect(new_session_button_, SIGNAL(clicked(bool)),
diff --git a/pv/mainwindow.hpp b/pv/mainwindow.hpp
index 9d5b0412..0904845f 100644
--- a/pv/mainwindow.hpp
+++ b/pv/mainwindow.hpp
@@ -129,6 +129,7 @@ private:
 
 	std::map< std::shared_ptr<Session>, QMainWindow*> session_windows_;
 
+	QWidget *static_tab_widget_;
 	QToolButton *new_session_button_;
 	QTabWidget session_selector_;
 
-- 
2.30.2