Use range-based for loops in ScreenManager.cpp

Modernizing some of the old code - improve reliability by replacing traditional iterator loops where they are not needed.

Update ScreenManager.cpp

src/ScreenManager.cpp

@@ -266,15 +266,17 @@ ScreenManager::~ScreenManager()
 	LOG->UnmapLog("ScreenManager::TopScreen");
 
 	SAFE_DELETE(g_pSharedBGA);
-	for( unsigned i=0; i<g_ScreenStack.size(); i++ )
+	for (LoadedScreen& screen : g_ScreenStack)
 	{
-		if( g_ScreenStack[i].m_bDeleteWhenDone )
+		if (screen.m_bDeleteWhenDone)
-			SAFE_DELETE( g_ScreenStack[i].m_pScreen );
+			SAFE_DELETE(screen.m_pScreen);
 	}
 	g_ScreenStack.clear();
 	DeletePreparedScreens();
-	for( unsigned i=0; i<g_OverlayScreens.size(); i++ )
+	for (Screen* overlayScreen : g_OverlayScreens)
-		SAFE_DELETE( g_OverlayScreens[i] );
+	{
+		SAFE_DELETE(overlayScreen);
+	}
 	g_OverlayScreens.clear();
 
 	// Unregister with Lua.
@@ -306,17 +308,17 @@ void ScreenManager::ThemeChanged()
 void ScreenManager::ReloadOverlayScreens()
 {
 	// unload overlay screens
-	for( unsigned i=0; i<g_OverlayScreens.size(); i++ )
+	for (Screen* screen : g_OverlayScreens)
-		SAFE_DELETE( g_OverlayScreens[i] );
+		SAFE_DELETE(screen);
 	g_OverlayScreens.clear();
 
 	// reload overlay screens
 	RString sOverlays = THEME->GetMetric("Common", "OverlayScreens");
 	std::vector<RString> asOverlays;
 	split(sOverlays, ",", asOverlays);
-	for( unsigned i=0; i<asOverlays.size(); i++ )
+	for (const RString& overlay : asOverlays)
 	{
-		Screen *pScreen = MakeNewScreen( asOverlays[i] );
+		Screen* pScreen = MakeNewScreen(overlay);
 		if (pScreen)
 		{
 			LuaThreadVariable var2("LoadingScreen", pScreen->GetName());
@@ -467,15 +469,13 @@ void ScreenManager::Update( float fDeltaTime )
 	}
 
 	// Update screens.
-	{
+	for (const LoadedScreen& screen : g_ScreenStack)
-		for( unsigned i=0; i<g_ScreenStack.size(); i++ )
+		screen.m_pScreen->Update(fDeltaTime);
-			g_ScreenStack[i].m_pScreen->Update( fDeltaTime );
 
 	g_pSharedBGA->Update(fDeltaTime);
 
-		for( unsigned i=0; i<g_OverlayScreens.size(); i++ )
+	for (Screen* overlay : g_OverlayScreens)
-			g_OverlayScreens[i]->Update( fDeltaTime );
+		overlay->Update(fDeltaTime);
-	}
 
 	/* The music may be started on the first update. If we're reading from a CD,
 	 * it might not start immediately. Make sure we start playing the sound before
@@ -509,12 +509,11 @@ void ScreenManager::Draw()
 	g_pSharedBGA->Draw();
 	DISPLAY->CameraPopMatrix();
 
-	for( unsigned i=0; i<g_ScreenStack.size(); i++ )	// Draw all screens bottom to top
+	for (const LoadedScreen& screen : g_ScreenStack)	// Draw all screens bottom to top
-		g_ScreenStack[i].m_pScreen->Draw();
+		screen.m_pScreen->Draw();
-
-	for( unsigned i=0; i<g_OverlayScreens.size(); i++ )
-		g_OverlayScreens[i]->Draw();
 
+	for (Screen* overlayScreen : g_OverlayScreens)
+		overlayScreen->Draw();
 
 	DISPLAY->EndFrame();
 }
@@ -527,9 +526,8 @@ void ScreenManager::Input( const InputEventPlus &input )
 
 	// First, give overlay screens a shot at the input.  If Input returns
 	// true, it handled the input, so don't pass it further.
-	for( unsigned i = 0; i < g_OverlayScreens.size(); ++i )
+	for (Screen* pScreen : g_OverlayScreens)
 	{
-		Screen *pScreen = g_OverlayScreens[i];
 		bool handled = pScreen->Input(input);
 		// Pass input to the screen and lua. Contention shouldn't be a problem
 		// because anybody setting an input callback is probably doing it to