title: Flutter: Update specific screen using provider that's consumed in multiple screens
body: <p>I have a typical CRUD operation task: (List Sites, Add Site, ...)</p>
  <p>I created a <code>SitesProvider</code>. In the same provider, I added 2 methods for add and edit. I was thinking to use the same provider in the 2 screens (<code>ListSites</code> and <code>AddEditSite</code>)</p>
  <p>In the <code>ListSites</code> screen, it works fine. Here is the problem:</p>
  <ul>
  <li>I open the <code>AddSite</code> screen by clicking the <code>AddButton</code> in the ListSites screen</li>
  <li>Hit submit (did not enter data, simulating error case)</li>
  <li>The error gets displayed in the <code>ListSites</code> screen, not in the <code>AddSite</code> screen.</li>
  </ul>
  <p>It makes sense. They both use the same provider, both screens are on the stack. It seems that the first one only consumes the state update and displays the error.</p>
  <p>I use <code>MultipleProviders</code> approach that wraps the MaterialApp with all providers in the app.</p>
  <p>Can we fix that without creating separate providers for each of the 2 screens?</p>
  <p><strong>EDIT:</strong></p>
  <p>I used <code>provider.removeListener</code> in the <code>ListSites</code> screen right before I open the AddEdit and it shows the error in the correct screen now. I still have to do some other tweaks to get it back to listen after I add. Not efficient I think but it is a step.</p>