Just try and you will see is not complicated. I was afraid to do it, but when you start, you will see is not so hard.
Just create a class, and start moving the subs and declarations of your smmricheditor to that class.
Then all you have to do is declarate an object in your activity of that class, and call the methods.
You will find a couple of problems in the process, but you will be able of solving them with searching in the forum about classes.
Really, try it and you will find is easier than you think.
Take a look to this lesson: