A little Script Creator work and little checks. (#9)

* No builds allowed here.

* Try something.

* Next work.

* Add some Logging stuff for testing purpose.

* Ok, this should log it priperly.

* Replace MainMenu with Screen Selection.

* Redo Screen Logic.

* Switch back to old MainMenu.

* Only access Scriptlist, when Scripts are found.

Hopefully avoid crashes with that.

* Remove unused String, because we use the MainMenu again.

source/screens/screen.cpp

@@ -0,0 +1,73 @@
+/*
+*   This file is part of Universal-Updater
+*   Copyright (C) 2019 DeadPhoenix8091, Epicpkmn11, Flame, RocketRobz, StackZ, TotallyNotGuy
+*
+*   This program is free software: you can redistribute it and/or modify
+*   it under the terms of the GNU General Public License as published by
+*   the Free Software Foundation, either version 3 of the License, or
+*   (at your option) any later version.
+*
+*   This program is distributed in the hope that it will be useful,
+*   but WITHOUT ANY WARRANTY; without even the implied warranty of
+*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*   GNU General Public License for more details.
+*
+*   You should have received a copy of the GNU General Public License
+*   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+*   Additional Terms 7.b and 7.c of GPLv3 apply to this file:
+*       * Requiring preservation of specified reasonable legal notices or
+*         author attributions in that material or in the Appropriate Legal
+*         Notices displayed by works containing it.
+*       * Prohibiting misrepresentation of the origin of that material,
+*         or requiring that modified versions of such material be marked in
+*         reasonable ways as different from the original version.
+*/
+
+#include "screens/screen.hpp"
+
+#include <stack>
+
+// Fade stuff.
+int fadealpha = 255;
+bool fadein = true;
+
+std::stack<std::unique_ptr<screen>> screens;
+
+// Set a specific Screen.
+void Screen::set(std::unique_ptr<screen> screen2)
+{
+	screens.push(std::move(screen2));
+}
+
+// Fade into another Screen, but first do a fadeout.
+void Screen::fade(std::unique_ptr<screen> screen2, bool fadeout) {
+	if (fadeout) {
+		fadealpha += 6;
+		if (fadealpha > 255) {
+			fadealpha = 255;
+			screens.push(std::move(screen2));
+			fadein = true;
+			fadeout = false;
+		}
+	}
+}
+
+// Go a Screen back.
+void Screen::back()
+{
+	screens.pop();
+}
+
+// For the Mainloop.
+void Screen::loop(u32 hDown, u32 hHeld, touchPosition touch) {
+	screens.top()->Draw();
+	screens.top()->Logic(hDown, hHeld, touch);
+	if (fadein == true) {
+		fadealpha -= 6;
+		if (fadealpha < 0) {
+			fadealpha = 0;
+			fadein = false;
+		}
+	}
+}