title: how to figure out the flow of an android project using debug
body: <p>I'm new to android development. 
  I download a toy project and want to figure out the flow of this project.
  Can I use debugging to figure out it and how?</p>
  
  <p>Let me explain it more detail. Every android project starts from an "main" activity. I guess I find the "main" activity for the project and set a breakpoint at the <code>onCreate</code> method of this "main" activity. I expect to run this project from that breakpoint one step by step to figure out the flow. However it doesn't work since the debugging stop after finishing the <code>onCreate</code> method.</p>