Need Help with creating a sliding button to access camera

Hello All!

I need your help with an app I’m trying to create, I just don’t know where to start, the basic idea of the app is to have the screen split up in two sides, the left is for video and the right is for photos, if you slide a side up it will start the camera with the rear camera and the opposite if you slide down. pretty simple right? but for a noob like me its confusing… 

I just need to be pointed in the right direction!

should i use a rectangle for the slider? and some how create a function for when it reaches an end it starts the camera? 

tumblr_ndxoymcJwn1tfzu4fo1_1280.jpg

anyone got any info?

anyone got any info?