added cyclic update

mainwindow.h

@@ -16,11 +16,13 @@ class MainWindow : public QMainWindow
     Q_OBJECT
 
 public:
-    explicit MainWindow(QWidget *parent = 0);
+    explicit MainWindow(QWidget *parent = nullptr);
     ~MainWindow();
 
     void setPowerState();
     
+    void updateAVState();
+
 private slots:
     void on_btn_onoff_clicked();
     void replyFinished(QNetworkReply *reply);
@@ -38,11 +40,14 @@ private:
     Ui::MainWindow *ui;
 
     QString mAddress;
-    QTimer mTimer;
+    QTimer mTimerValCollect;
+    QTimer mTimerUpdate;
+
     bool mPowered = false;
     int mVolume = 0;
     QString mInput;
-    const int WAITTIME = 400;
+    const int COLLECTTIME = 400;
+    const int UPDATETIME = 20000;
 
     void sendCommand(QString cmd);
     void updateUi();