Qt Quick Demo - Tweet Search

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  import QtQuick 2.0
  import "tweetsearch.mjs" as Helper

  Item {
      id: wrapper

      // Insert valid consumer key and secret tokens below
      // See https://dev.twitter.com/apps
      property string consumerKey : ""
      property string consumerSecret : ""
      property string bearerToken : ""

      property variant model: tweets
      property string from : ""
      property string phrase : ""

      signal isLoaded

      ListModel { id: tweets }

      function encodePhrase(x) { return encodeURIComponent(x); }

      function reload() {
          tweets.clear()

          if (from == "" && phrase == "")
              return;

          var req = new XMLHttpRequest;
          req.open("GET", "https://api.twitter.com/1.1/search/tweets.json?from=" + from +
                          "&count=10&q=" + encodePhrase(phrase));
          req.setRequestHeader("Authorization", "Bearer " + bearerToken);
          req.onload = function() {
              var objectArray = JSON.parse(req.responseText);
              if (objectArray.errors !== undefined) {
                  console.log("Error fetching tweets: " + objectArray.errors[0].message)
              } else {
                  for (var key in objectArray.statuses) {
                      var jsonObject = objectArray.statuses[key];
                      tweets.append(jsonObject);
                  }
              }
              wrapper.isLoaded()
          }
          req.send();
      }

      onPhraseChanged: reload();
      onFromChanged: reload();

      Component.onCompleted: {
          if (consumerKey === "" || consumerSecret == "") {
              bearerToken = encodeURIComponent(Helper.demoToken())
              return;
          }

          var authReq = new XMLHttpRequest;
          authReq.open("POST", "https://api.twitter.com/oauth2/token");
          authReq.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;charset=UTF-8");
          authReq.setRequestHeader("Authorization", "Basic " + Qt.btoa(consumerKey + ":" + consumerSecret));
          authReq.onreadystatechange = function() {
              if (authReq.readyState === XMLHttpRequest.DONE) {
                  var jsonResponse = JSON.parse(authReq.responseText);
                  if (jsonResponse.errors !== undefined)
                      console.log("Authentication error: " + jsonResponse.errors[0].message)
                  else
                      bearerToken = jsonResponse.access_token;
              }
          }
          authReq.send("grant_type=client_credentials");
      }

  }