This app crashes when I click the start icon

Project Information:

• Repository: https://github.com/olgamiller/SSTVEncoder2

Expected behavior:

It is expected that when users click on the Start button, it will start. And when it stops, it will be able to stop.

Actual behavior:

It starts when I click on the Start icon, but when I click again this app crashes.

How to reproduce:

• download the app

• then click on start icon

• run it but again click icon for stop

• crashes this app

• Browser/App version: 2.1

• Operating system: android 6.0

Recording Of The Bug:

Proof of Work Done:

https://github.com/thamidur