Introduce and use Engine_Empty() and Engine::GUIErrorMessage()

svn-id: r22165

2 files changed, 39 insertions, 0 deletions

diff --git a/base/engine.cpp b/base/engine.cpp
index a01a7df533..55cbf2f65b 100644
--- a/base/engine.cpp
+++ b/base/engine.cpp
@@ -248,3 +248,18 @@ void checkHeap() {
 	}
 #endif
 }
+
+void Engine::GUIErrorMessage(const Common::String msg) {
+	_system->setWindowCaption("Error");
+	_system->beginGFXTransaction();
+		initCommonGFX(false);
+		_system->initSize(320, 200, 2);
+	_system->endGFXTransaction();
+
+	GUI::MessageDialog dialog(msg);
+	dialog.runModal();
+}
+
+Engine_Empty::Engine_Empty(OSystem *syst, const Common::String msg) : Engine(syst), _message(msg) {
+}
+
diff --git a/base/engine.h b/base/engine.h
index 73d4264883..73d1a9cd3b 100644
--- a/base/engine.h
+++ b/base/engine.h
@@ -77,8 +77,32 @@ public:
 
 	/* Indicate if an autosave should be performed */
 	bool shouldPerformAutoSave(int lastSaveTime);
+
+	/** Initialized graphics and shows error message */
+	void GUIErrorMessage(const Common::String msg);
 };
 
+// Used when no valid game was found in the directory
+// Just pops up an error message and returns to launcher
+class Engine_Empty : public Engine {
+public:
+	Engine_Empty(OSystem *syst, const Common::String msg = "No valid games were found in specified directory.");
+	virtual ~Engine_Empty() {}
+
+	// Displays error message
+	int init() { GUIErrorMessage(_message); return 0; }
+
+	// Just indicate that we want return to launcher
+	int go() { return 1; }
+
+	void errorString(char *buf_input, char *buf_output) {}
+
+private:
+	Common::String _message;
+};
+
+
+
 extern Engine *g_engine;
 
 #endif