finished navigation including music player and navigate back

functionality

LenaPi/models/UiStateModel.cpp

@@ -0,0 +1,21 @@
+#include "UiStateModel.h"
+
+UiStateModel::UiStateModel(QObject *parent) : QObject(parent)
+{
+    showNavigation();
+}
+
+QUrl UiStateModel::getSource() const
+{
+    return mSource;
+}
+
+void UiStateModel::showMusicPlayer(){
+    mSource = QUrl("MusicPlayer.qml");
+    emit sourceChanged();
+}
+
+void UiStateModel::showNavigation(){
+    mSource = QUrl("Navigation.qml");
+    emit sourceChanged();
+}