title: How do I open a specific page on onesignal notification click on flutter?
body: <p>I am using OneSignal push notification service and I want to open the app directly to specific page on notification click. I am sending the page through data. I tried navigator.push but it didn't work i guess because of context issue. I am calling _initializeonesignal() after login which contains onesignal init and the following code.</p>
  
  <pre><code>OneSignal.shared.setNotificationOpenedHandler((notification) {
    var notify = notification.notification.payload.additionalData;
    if (notify["type"] == "message") {
      //open DM(user: notify["id"])
    }
    if (notify["type"] == "user") {
     //open Profileo(notify["id"])
    }
    if (notify["type"] == "post") {
      //open ViewPost(notify["id"])
    }
    print('Opened');
  });
  </code></pre>