title: iPhone UIWebView back button
body: <p>I am trying to make a back button in my navigation bar because i already have a tab bar at the bottom of the screen.</p>
  
  <p>my layout is this: </p>
  
  <pre><code>tab bar[
  navigation bar {
  webview ()
  }
  ]
  </code></pre>
  
  <p>essentially. i need to programmatically add a back button and cannot seem to figure out how. i know that there is a goBack method but am not very familiar with how to implement this. </p>
  
  <p>I already have a button which pulls up ana action sheet with several options but how would i go about having that use the goBack method?</p>
  
  <p>as I understand I can also use something like </p>
  
  <pre><code>if (mywebview canGoBack) {
      [mywebview goBack]
  }
  </code></pre>
  
  <p>but I'm not sure how to make an action sheet button do this. </p>
  
  <p>any help?</p>