Optimized Button class. Added IsPressed and GetPressed methods.

src/system/BaseSystem.cpp

@@ -5,4 +5,9 @@ namespace ehs
 	void BaseSystem::OpenURI(const Str_8& uri)
 	{
 	}
-}
+
+	Str_8 BaseSystem::OpenFileDialog(const Str_8 &dir, const Str_8 &filters)
+	{
+		return {};
+	}
+}

src/system/System_LNX.cpp

@@ -1,4 +1,7 @@
 #include "ehs/system/System_LNX.h"
+
+#include <cstdio>
+
 #include "ehs/system/Thread.h"
 #include "ehs/Log.h"
 
@@ -19,4 +22,22 @@ namespace ehs
 		xdg.Start(XDG_Thread, (void*)&uri);
 		xdg.Detach();
 	}
-}
+
+	Str_8 System::OpenFileDialog(const Str_8 &dir, const Str_8 &filters)
+	{
+		FILE *file = popen("kdialog --getopenfilename " + dir + " \'" + filters + "\'", "r");
+
+		Str_8 result;
+
+		char array[128];
+		while(fgets(array, sizeof(array), file))
+			result.Push(array);
+
+		pclose(file);
+
+		if (result.Size())
+			result.Pop();
+
+		return result;
+	}
+}