added the previous item change

src/qml/presenter/Presentation.qml

@@ -177,24 +177,38 @@ Item {
     }
 
     function previousSlideAction() {
-        print(textIndex);
-        if (itemType === "song") {
-            if (textIndex === 0) {
-                clearText();
-                nextSlide();
-            } else if (textIndex <= root.text.length) {
-                SlideObject.setText(root.text[textIndex]);
-                print(root.text[textIndex]);
-                --textIndex;
+        const prevServiceItemIndex = currentServiceItem - 1;
+        const prevItem = serviceItemModel.getItem(prevServiceItemIndex);
+        print("currentServiceItem " + currentServiceItem);
+        print("prevServiceItem " + prevServiceItemIndex);
+        print(prevItem.name);
+        const changed = SlideObject.previous(prevItem);
+        print(changed);
+        if (changed) {
+            currentServiceItem--;
+            loadVideo();
         }
-        } else if (itemType === "video") {
+
+
+
+        /* print(textIndex); */
+        /* if (itemType === "song") { */
+        /*     if (textIndex === 0) { */
         /*         clearText(); */
-            previousSlide();
-        }
-        else if (itemType === "image") {
-            /* clearText(); */
-            previousSlide();
-        }
+        /*         nextSlide(); */
+        /*     } else if (textIndex <= root.text.length) { */
+        /*         SlideObject.setText(root.text[textIndex]); */
+        /*         print(root.text[textIndex]); */
+        /*         --textIndex; */
+        /*     } */
+        /* } else if (itemType === "video") { */
+        /*     /\* clearText(); *\/ */
+        /*     previousSlide(); */
+        /* } */
+        /* else if (itemType === "image") { */
+        /*     /\* clearText(); *\/ */
+        /*     previousSlide(); */
+        /* } */
     }
 
     function previousSlide() {

src/slide.cpp

@@ -210,3 +210,24 @@ bool Slide::next(QVariantMap nextItem)
 
   return false;
 }
+
+bool Slide::previous(QVariantMap prevItem)
+{
+  qDebug() << "Starting to go to previous item.";
+  qDebug() << "Slide Index: " << m_slideIndex << " Slide Size: " << m_slideSize;
+  QStringList text = m_serviceItem.value("text").toStringList();
+  if (m_slideIndex == 1) {
+    changeSlide(prevItem);
+    return true;
+  }
+
+  // since the string list is 0 indexed m_slideIndex actually
+  // maps to the next item. So the prev text is minus 2
+  int prevTextIndex = m_slideIndex - 2;
+  qDebug() << prevTextIndex;
+  qDebug() << text[prevTextIndex];
+  setText(text[prevTextIndex]);
+  m_slideIndex--;
+
+  return false;
+}

src/slide.h

@@ -53,6 +53,7 @@ public:
 
   Q_INVOKABLE void changeSlide(QVariantMap item);
   Q_INVOKABLE bool next(QVariantMap nextItem);
+  Q_INVOKABLE bool previous(QVariantMap prevItem);
 
 signals:
     Q_INVOKABLE void textChanged(QString text);