Qt 5.11 | Qt Quick | Qt Quick Demo - Tweet Search | TweetsModel.qml Example File

Qt 5.11.3 Reference Documentation

# TweetsModel.qml Example File

demos/tweetsearch/content/TweetsModel.qml

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      import QtQuick 2.0
      import "tweetsearch.js" 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 : ""

          property int status: XMLHttpRequest.UNSENT
          property bool isLoading: status === XMLHttpRequest.LOADING
          property bool wasLoading: false
          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.onreadystatechange = function() {
                  status = req.readyState;
                  if (status === XMLHttpRequest.DONE) {
                      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);
                          }
                      }
                      if (wasLoading == true)
                          wrapper.isLoaded()
                  }
                  wasLoading = (status === XMLHttpRequest.LOADING);
              }
              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");
          }

      }