Fix transparent backgrounds

It's apparently not possible to set WA_TranslucentBackground after
show(). The MainWindow constructor calls applyKonsoleSettings() which
calls KMainWindow::setAutoSaveSettings() which in turn calls
setVisible(true), which makes any calls to setTransparency() from the
Application::newMainWindow() irrelevant, even if updateUseTransparency()
is called from it.

REVIEW: 128669
BUG: 366368
(cherry picked from commit a28902e912)

src/Application.cpp

@@ -40,6 +40,7 @@
 #include "KonsoleSettings.h"
 #include "ViewManager.h"
 #include "SessionController.h"
+#include "WindowSystemInfo.h"
 
 using namespace Konsole;
 
@@ -56,8 +57,9 @@ Application::~Application()
 
 MainWindow* Application::newMainWindow()
 {
+    WindowSystemInfo::HAVE_TRANSPARENCY = !m_parser.isSet(QStringLiteral("notransparency"));
+
     MainWindow* window = new MainWindow();
-    window->setTransparency(!m_parser.isSet(QStringLiteral("notransparency")));
 
     connect(window, &Konsole::MainWindow::newWindowRequest, this, &Konsole::Application::createWindow);
     connect(window, &Konsole::MainWindow::viewDetached, this, &Konsole::Application::detachView);

src/MainWindow.cpp

@@ -64,7 +64,6 @@ MainWindow::MainWindow()
     , _pluggedController(0)
     , _menuBarInitialVisibility(true)
     , _menuBarInitialVisibilityApplied(false)
-    , _useTransparency(false)
 {
     if (!KonsoleSettings::saveGeometryOnExit()) {
         // If we are not using the global Konsole save geometry on exit,
@@ -83,8 +82,6 @@ MainWindow::MainWindow()
         }
     }
 
-    connect(KWindowSystem::self(), &KWindowSystem::compositingChanged, this, &MainWindow::updateUseTransparency);
-
     updateUseTransparency();
 
     // create actions for menus
@@ -129,11 +126,14 @@ MainWindow::MainWindow()
 
 void MainWindow::updateUseTransparency()
 {
-    bool useTranslucency = KWindowSystem::compositingActive() && _useTransparency;
+    if (!WindowSystemInfo::HAVE_TRANSPARENCY) {
+        return;
+    }
+
+    bool useTranslucency = KWindowSystem::compositingActive();
 
     setAttribute(Qt::WA_TranslucentBackground, useTranslucency);
     setAttribute(Qt::WA_NoSystemBackground, false);
-
     WindowSystemInfo::HAVE_TRANSPARENCY = useTranslucency;
 }
 
@@ -765,11 +765,6 @@ void MainWindow::setShowQuickButtons(bool show)
     _viewManager->setShowQuickButtons(show);
 }
 
-void MainWindow::setTransparency(bool useTransparency)
-{
-    _useTransparency = useTransparency;
-}
-
 void MainWindow::activateMenuBar()
 {
     const QList<QAction*> menuActions = menuBar()->actions();

src/MainWindow.h

@@ -109,7 +109,6 @@ public:
     void setNavigationStyleSheetFromFile(const QUrl& stylesheetfile);
     void setNavigationBehavior(int behavior);
     void setShowQuickButtons(bool show);
-    void setTransparency(bool useTransparency);
 
 signals:
 
@@ -211,7 +210,6 @@ private:
 
     bool _menuBarInitialVisibility;
     bool _menuBarInitialVisibilityApplied;
-    bool _useTransparency;
 };
 }