title: Within a VSCode extension is it possible to have a panel that switches between a webview and tree view
body: <p>i want to add a new explorer panel into vscode. I want it to display either a treeView or a webView depending on if the user has connected to my backend application. I can see something similar in the base of vscode in the folder view. When no folder is open this view is shown </p>
  
  <p><a href="https://i.stack.imgur.com/pGKTK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/pGKTK.png" alt="Folder view no folder open"></a></p>
  
  <p>and when you have a folder open it looks like</p>
  
  <p><a href="https://i.stack.imgur.com/WVVe6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/WVVe6.png" alt="Folder view with folder open"></a></p>