Allow arbitrary resizing of the main window & restore sidebar's size

fixes #160
fixes #163
fixes #187
fixes #127

include/MainWindow.h

@@ -83,14 +83,23 @@ private slots:
         void showWelcomePage()
         {
                 removeOverlayProgressBar();
+                pageStack_->addWidget(welcome_page_);
                 pageStack_->setCurrentWidget(welcome_page_);
         }
 
         //! Show the login page in the main window.
-        void showLoginPage() { pageStack_->setCurrentWidget(login_page_); }
+        void showLoginPage()
+        {
+                pageStack_->addWidget(login_page_);
+                pageStack_->setCurrentWidget(login_page_);
+        }
 
         //! Show the register page in the main window.
-        void showRegisterPage() { pageStack_->setCurrentWidget(register_page_); }
+        void showRegisterPage()
+        {
+                pageStack_->addWidget(register_page_);
+                pageStack_->setCurrentWidget(register_page_);
+        }
 
         //! Show user settings page.
         void showUserSettingsPage() { pageStack_->setCurrentWidget(userSettingsPage_); }

include/Splitter.h

@@ -24,6 +24,9 @@ class Splitter : public QSplitter
         Q_OBJECT
 public:
         explicit Splitter(QWidget *parent = nullptr);
+        ~Splitter();
+
+        void restoreSizes(int fallback);
 
 private:
         void onSplitterMoved(int pos, int index);

src/ChatPage.cc

@@ -118,7 +118,7 @@ ChatPage::ChatPage(QSharedPointer<UserSettings> userSettings, QWidget *parent)
         // Splitter
         splitter->addWidget(sideBar_);
         splitter->addWidget(content_);
-        splitter->setSizes({ui::sidebar::NormalSize, parent->width() - ui::sidebar::NormalSize});
+        splitter->restoreSizes(parent->width());
 
         text_input_    = new TextInputWidget(this);
         typingDisplay_ = new TypingDisplay(this);

src/MainWindow.cc

@@ -234,9 +234,12 @@ MainWindow::showChatPage()
 
         showOverlayProgressBar();
 
-        welcome_page_->hide();
         pageStack_->setCurrentWidget(chat_page_);
 
+        pageStack_->removeWidget(welcome_page_);
+        pageStack_->removeWidget(login_page_);
+        pageStack_->removeWidget(register_page_);
+
         login_page_->reset();
         chat_page_->bootstrap(userid, homeserver, token);
 

src/Splitter.cc

@@ -16,6 +16,7 @@
  */
 
 #include <QDebug>
+#include <QSettings>
 
 #include "Splitter.h"
 #include "Theme.h"
@@ -28,6 +29,43 @@ Splitter::Splitter(QWidget *parent)
         setStyleSheet("QSplitter::handle { image: none; }");
 }
 
+void
+Splitter::restoreSizes(int fallback)
+{
+        QSettings settings;
+        int savedWidth = settings.value("sidebar/width").toInt();
+
+        auto left = widget(0);
+        if (savedWidth == ui::sidebar::SmallSize) {
+                if (left) {
+                        left->setMinimumWidth(ui::sidebar::SmallSize);
+                        left->setMaximumWidth(ui::sidebar::SmallSize);
+                        return;
+                }
+        }
+
+        if (savedWidth >= ui::sidebar::NormalSize && savedWidth <= 2 * ui::sidebar::NormalSize) {
+                if (left) {
+                        left->setMinimumWidth(ui::sidebar::NormalSize);
+                        left->setMaximumWidth(2 * ui::sidebar::NormalSize);
+                        setSizes({savedWidth, fallback - savedWidth});
+                        return;
+                }
+        }
+
+        setSizes({ui::sidebar::NormalSize, fallback - ui::sidebar::NormalSize});
+}
+
+Splitter::~Splitter()
+{
+        auto left = widget(0);
+
+        if (left) {
+                QSettings settings;
+                settings.setValue("sidebar/width", left->width());
+        }
+}
+
 void
 Splitter::onSplitterMoved(int pos, int index)
 {