Play audio file from position where the slider is changed

Hii, i have a problem i want to create an app that plays an audio file. I've got the app to move the slider along as the audio file plays, to calculate and display the total time of the audio file and a few other things.

Now i want the user to be able to play the audio file from where they change the sliders position to. When that happens the timelapse should also adjust to the position where the slider is placed.

This is how the app looks on a device:

And these are by blocks of code:

Can anyone please help me with this?