title: Check if Timer is running
body: <p>I have been trying to refill in game lives with a timer, but whenever I leave a view and return, the timer duplicates and becomes faster. I have tried to address this with the <code>Timer?.isValid</code> function to only run the timer when it is invalid so it never duplicates, but it cannot seem to check is the timer is <strong>invalid</strong> in an if statement.</p>
  
  <p>This is the if statement that I have been using so far:</p>
  
  <pre><code>if (myTimer?.isValid){
  } else{
  //start timer
  }
  </code></pre>
  
  <p>Any help would be appreciated, thanks.</p>