Initial commit

Lts/Common/LtsUtils/LtsUtilsGui/StyleManager/style_manager.cpp

@@ -0,0 +1,121 @@
+/**
+  * @RDE_HEADER@
+  * Loads Style Plugins and unloads them to keep one resource file only
+  * $Id$
+  * $HeadURL$
+  * $Author$
+  *
+  * Created by Mike Wille, NLSE, 2018-02-15
+  */
+
+#include "style_manager.h"
+
+#include <LtsPluginManager/lts_plugin_loader.h>
+#include <PluginInterfaces/style_plugin_interface.h>
+
+#include <QPluginLoader>
+#include <QDebug>
+
+
+namespace LtsUtils
+{
+
+struct StyleManagerHandler
+{
+  StyleManager styleManager;
+};
+Q_GLOBAL_STATIC(StyleManagerHandler, s_styleManagerHandler)
+
+
+StyleManager *StyleManager::getInstance()
+{
+  return &s_styleManagerHandler->styleManager;
+}
+
+bool StyleManager::loadStyle(const QString &stylePluginName, bool highDpi)
+{
+  if (m_currentStylePluginLoader != nullptr) // a style was already loaded - unload first
+  {
+    //qWarning() << "StyleManager::loadStyle: style" << m_currentStylePluginLoader->instance()->metaObject()->className() << "already loaded - unloading";
+
+    QObject *pluginInstance = m_currentStylePluginLoader->instance();
+    StylePlugin::Plugin *sp = qobject_cast<StylePlugin::Plugin *>(pluginInstance);
+
+    if (sp == nullptr)
+    {
+      qWarning() << "StyleManager::loadStyle: could not unload style plugin - wrong type ("
+                 << pluginInstance->metaObject()->className() << ") - new style not loaded";
+      return false;
+    }
+
+    sp->unloadStyle();
+
+    // Do not do the job of the LtsPluginLoader
+//    delete sp;
+
+//    if (!m_currentStylePluginLoader->unload())
+//    {
+//      qWarning() << "StyleManager::loadStyle: could not unload old style" << m_currentStylePluginLoader->errorString();
+//    }
+
+    m_currentStylePluginLoader = nullptr;
+  }
+
+
+  // load new plugin
+  LtsPluginManager::LtsPluginLoader *pluginLoader = LtsPluginManager::LtsPluginLoader::getInstance();
+
+  QPluginLoader *stylePluginLoader = nullptr;
+  int pluginsLoaded = 0;
+
+  std::function<bool(const LtsPluginManager::PluginInstance &pi)> loadPluginFn = [&stylePluginLoader, &pluginsLoaded]
+                                                                                 (const LtsPluginManager::PluginInstance &pi)
+  {
+    stylePluginLoader = pi.pluginLoader;
+    pluginsLoaded++;
+    return true;
+  };
+
+  if (!pluginLoader->loadPlugins(LtsPluginManager::PluginType::STYLE, loadPluginFn, QStringList() << stylePluginName))
+  {
+    qWarning() << "StyleManager::loadStyle: Error loading Style Plugin - using default Qt style";
+    return false;
+  }
+
+  if (pluginsLoaded == 0)
+  {
+    qWarning() << "StyleManager::loadStyle: Could not find Style Plugin" << stylePluginName << "- using default Qt style";
+    return false;
+  }
+
+  if (pluginsLoaded > 1)
+  {
+    qWarning() << "StyleManager::loadStyle: Style Plugin" << stylePluginName << " is ambiguous - using default Qt style";
+    return false;
+  }
+
+  if (stylePluginLoader == nullptr)
+  {
+    qWarning() << "StyleManager::loadStyle: No Style Plugin loader available - using default Qt style";
+    return false;
+  }
+
+  StylePlugin::Plugin *sp = qobject_cast<StylePlugin::Plugin *>(stylePluginLoader->instance());
+
+  if (sp == nullptr)
+  {
+    qWarning() << "StyleManager::loadStyle: could not load style plugin - wrong type ("
+               << stylePluginLoader->instance()->metaObject()->className() << ") - new style not loaded";
+    return false;
+  }
+
+  sp->loadStyle(highDpi);
+
+  m_currentStylePluginLoader = stylePluginLoader;
+  m_stylePluginName = stylePluginName;
+  emit signalStyleChanged(stylePluginName);
+
+  return true;
+}
+
+} // namespace LtsUtils