Timeline: Be more exact about height of model aggregator

Only emit the change signal if the height has actually changed.

Change-Id: Ic4bf67f25cb4a7f204815b4e6b0c6bd88c71944a
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>

2 files changed, 9 insertions, 4 deletions

diff --git a/src/libs/timeline/timelinemodelaggregator.cpp b/src/libs/timeline/timelinemodelaggregator.cpp
index bad5462fc5..b363752058 100644
--- a/src/libs/timeline/timelinemodelaggregator.cpp
+++ b/src/libs/timeline/timelinemodelaggregator.cpp
@@ -53,10 +53,6 @@ TimelineModelAggregator::TimelineModelAggregator(TimelineNotesModel *notes, QObj
     : QObject(parent), d(new TimelineModelAggregatorPrivate(this))
 {
     d->notesModel = notes;
-    connect(this, &TimelineModelAggregator::modelsChanged,
-            this, &TimelineModelAggregator::heightChanged);
-    connect(this, &TimelineModelAggregator::stateChanged,
-            this, &TimelineModelAggregator::heightChanged);
 }
 
 TimelineModelAggregator::~TimelineModelAggregator()
@@ -76,6 +72,8 @@ void TimelineModelAggregator::addModel(TimelineModel *m)
     if (d->notesModel)
         d->notesModel->addTimelineModel(m);
     emit modelsChanged();
+    if (m->height() != 0)
+        emit heightChanged();
 }
 
 const TimelineModel *TimelineModelAggregator::model(int modelIndex) const
@@ -98,10 +96,13 @@ TimelineNotesModel *TimelineModelAggregator::notes() const
 
 void TimelineModelAggregator::clear()
 {
+    int prevHeight = height();
     d->modelList.clear();
     if (d->notesModel)
         d->notesModel->clear();
     emit modelsChanged();
+    if (height() != prevHeight)
+        emit heightChanged();
 }
 
 int TimelineModelAggregator::modelOffset(int modelIndex) const
diff --git a/tests/auto/timeline/timelinemodelaggregator/tst_timelinemodelaggregator.cpp b/tests/auto/timeline/timelinemodelaggregator/tst_timelinemodelaggregator.cpp
index 5eb229c7df..5de05069d1 100644
--- a/tests/auto/timeline/timelinemodelaggregator/tst_timelinemodelaggregator.cpp
+++ b/tests/auto/timeline/timelinemodelaggregator/tst_timelinemodelaggregator.cpp
@@ -54,13 +54,17 @@ void tst_TimelineModelAggregator::height()
     Timeline::TimelineModelAggregator aggregator(0);
     QCOMPARE(aggregator.height(), 0);
 
+    QSignalSpy heightSpy(&aggregator, SIGNAL(heightChanged()));
     Timeline::TimelineModel *model = new Timeline::TimelineModel(25, QString());
     aggregator.addModel(model);
     QCOMPARE(aggregator.height(), 0);
+    QCOMPARE(heightSpy.count(), 0);
     aggregator.addModel(new HeightTestModel);
     QVERIFY(aggregator.height() > 0);
+    QCOMPARE(heightSpy.count(), 1);
     aggregator.clear();
     QCOMPARE(aggregator.height(), 0);
+    QCOMPARE(heightSpy.count(), 2);
 }
 
 void tst_TimelineModelAggregator::addRemoveModel()