Make context menu "Extract" clearer (rename and add icon), and disable if no track is active

src/timeline2/view/qml/ClipMenu.qml

@@ -11,6 +11,7 @@ Menu {
         property bool grouped
         property bool canBeAudio
         property bool canBeVideo
+        property bool hasActiveTrack
         property bool canBeGrouped: timeline.isInSelection(clipId)
 
         onAboutToHide: {
@@ -18,6 +19,7 @@ Menu {
         }
         onAboutToShow: {
             canBeGrouped = timeline.isInSelection(clipId)
+            hasActiveTrack = timeline.hasActiveTracks()
         }
 
         MenuItem {
@@ -105,8 +107,10 @@ Menu {
             onTriggered: timeline.triggerAction('delete_timeline_clip')
         }
         MenuItem {
+            enabled: hasActiveTrack
             visible: true
-            text: i18n("Extract")
+            text: i18n("Extract Clip")
+            iconName: 'timeline-extract'
             onTriggered: timeline.extract(clipId)
         }
         MenuSeparator {

src/timeline2/view/timelinecontroller.cpp

@@ -2622,3 +2622,16 @@ void TimelineController::updateAudioTarget()
         m_audioTargetActive = false;
     }
 }
+
+bool TimelineController::hasActiveTracks() const
+{
+    auto it = m_model->m_allTracks.cbegin();
+    while (it != m_model->m_allTracks.cend()) {
+        int target_track = (*it)->getId();
+        if (m_model->getTrackById_const(target_track)->shouldReceiveTimelineOp()) {
+            return true;
+        }
+        ++it;
+    }
+    return false;
+}

src/timeline2/view/timelinecontroller.h

@@ -130,6 +130,10 @@ public:
      */
     Q_INVOKABLE void showConfig(int page, int tab);
 
+    /* @brief Returns true if we have at least one active track
+     */
+    Q_INVOKABLE bool hasActiveTracks() const;
+
     /* @brief returns current timeline's zoom factor
      */
     Q_INVOKABLE double scaleFactor() const;