Question

When I call a buttonHandler, the app just continues in the background even though the Handler didn’t finish, how can I stop this behaviour, and fall back to a linear execution?

qrscan.setOnClickListener( new View.OnClickListener() { //the Button listener
    public void onClick(View view) { //the handler
      if(initiateScan(activity) == null) //first thing i expect it to execute
         initiateSend(activity); //the next thing which should be executed AFTER
      }
   }
);

Answer 1

You aren’t saying much – we’ll need to know how initiateScan and initiateSend work, but it sounds like initiateScan is using startActivity or startActivityForResult to do it’s thing.

If so, you need to ensure they are using startActivityForResult, and move initiateSend to the onActivityResult method of your activity.

Activities are asynchronous entities and you need to make use of the onActivityResult callback to handle actions in the linear manner you are looking for.

For more info, read here.