Exam summary: Hide 'Analyze' button when no questions in exercise

- it occurs when exercise is stopped on first question
- also hide pie chart in that case

src/main/texamsummary.cpp

@@ -171,6 +171,11 @@ void TexamSummary::continueExecutor() {
 }
 
 
+bool TexamSummary::hasQuestions() const {
+  return m_exam && m_exam->count() > 0;
+}
+
+
 void TexamSummary::exerciseToExam() {
   m_accepted = true;
   EXECUTOR->restoreExerciseAfterSummary();

src/main/texamsummary.h

@@ -46,6 +46,7 @@ class TexamSummary : public QQuickItem
   Q_PROPERTY(QList<int> kindOfMistakes READ kindOfMistakes NOTIFY updateExam)
   Q_PROPERTY(bool hasVariousMistakes READ hasVariousMistakes NOTIFY updateExam)
   Q_PROPERTY(QList<int> answersModel READ answersModel NOTIFY updateExam)
+  Q_PROPERTY(bool hasQuestions READ hasQuestions NOTIFY updateExam)
 
 public:
   explicit TexamSummary(QQuickItem* parent = nullptr);
@@ -62,6 +63,8 @@ public:
   QList<int> kindOfMistakes() const { return m_kindOfMistakes; }
   QList<int> answersModel() const { return m_answersModel; }
 
+  bool hasQuestions() const;
+
       /**
        * @p TRUE when there are more than one kind of mistake
        */

src/qml/exam/ExamSummary.qml

@@ -66,6 +66,7 @@ TexamSummary {
               }
               Item {
                 width: NOO.factor() * (NOO.isAndroid() ? 15 : 20); height: width + NOO.factor()
+                visible: hasQuestions
                 TpieChartItem {
                   id: answId
                   width: parent.width; height: width
@@ -179,7 +180,7 @@ TexamSummary {
           onClicked: { continueExecutor(); dialLoader.close() }
         }
         TiconButton {
-          visible: !NOO.isAndroid() || !isExercise()
+          visible: hasQuestions && (!NOO.isAndroid() || !isExercise())
           width: buttGrid.buttWidth
           pixmap: NOO.pix(NOO.isAndroid() ? "send" : "charts"); iconHeight: buttGrid.buttHeight
           text: NOO.isAndroid() ? NOO.TR("QShortcut", "Send") : qsTr("Analyze")