Sets the position of the slider thumb. If this value is greater than
MaxValue, then it will be set to same value as MaxValue. If this value
is less than MinValue, then it will be set to same value as MinValue.
A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook http://www.appinventor.org/book2 ... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.
You will not find a tutorial, which does exactly what you are looking for. But doing the tutorials (not only reading a little bit) help you to understand, how things are working. This is important and this is the first step to do.