From 8b84374892512faa43e5deeeef22ca558ac5543a Mon Sep 17 00:00:00 2001 From: Axel Spoerl Date: Mon, 13 Mar 2023 09:16:06 +0100 Subject: [PATCH] emit QAbstractSlider::valueChanged() only on value change The signal has been emitted also, when the slider position has changed without a value change (e.g. on QWidget::show() or on resizing). This patch stops emitting the signal without a value change. It adds a verification to tst_QAbstractSlider::setValue(), that valueChanged is not emitted on a no-op value change. As a drive-by, the patch removes an unnecessary assignment and changes signal spy constructions to PTMF syntax. Pick-to: 6.5 6.4 6.2 Task-number: QTBUG-25365 Change-Id: I9932e45d4e680aa53422ca75aa42a16306213a38 Reviewed-by: Shawn Rutledge --- src/widgets/widgets/qabstractslider.cpp | 11 +++++++++-- .../widgets/qabstractslider/tst_qabstractslider.cpp | 10 +++++++--- 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/src/widgets/widgets/qabstractslider.cpp b/src/widgets/widgets/qabstractslider.cpp index 6e44b2d432..4e65fbac88 100644 --- a/src/widgets/widgets/qabstractslider.cpp +++ b/src/widgets/widgets/qabstractslider.cpp @@ -498,18 +498,25 @@ void QAbstractSlider::setValue(int value) value = d->bound(value); if (d->value == value && d->position == value) return; + + // delay signal emission until sliderChanged() has been called + const bool emitValueChanged = (value != d->value); d->value = value; + if (d->position != value) { d->position = value; if (d->pressed) - emit sliderMoved((d->position = value)); + emit sliderMoved(d->position); } #if QT_CONFIG(accessibility) QAccessibleValueChangeEvent event(this, d->value); QAccessible::updateAccessibility(&event); #endif sliderChange(SliderValueChange); - emit valueChanged(value); + + if (emitValueChanged) + emit valueChanged(value); + } /*! diff --git a/tests/auto/widgets/widgets/qabstractslider/tst_qabstractslider.cpp b/tests/auto/widgets/widgets/qabstractslider/tst_qabstractslider.cpp index 17caa091c6..170c29922a 100644 --- a/tests/auto/widgets/widgets/qabstractslider/tst_qabstractslider.cpp +++ b/tests/auto/widgets/widgets/qabstractslider/tst_qabstractslider.cpp @@ -2021,9 +2021,9 @@ void tst_QAbstractSlider::setValue() slider->setRange(minimum, maximum); slider->setSliderDown(down); slider->setValue(49); // to force a valueChanged() below - QSignalSpy spy1(slider, SIGNAL(sliderMoved(int))); - QSignalSpy spy2(slider, SIGNAL(valueChanged(int))); - QSignalSpy spy3(slider, SIGNAL(actionTriggered(int))); + QSignalSpy spy1(slider, &QAbstractSlider::sliderMoved); + QSignalSpy spy2(slider, &QAbstractSlider::valueChanged); + QSignalSpy spy3(slider, &QAbstractSlider::actionTriggered); slider->setValue(50); QCOMPARE(spy1.size(), down ? 1 : 0); QCOMPARE(spy2.size(), 1); @@ -2032,6 +2032,10 @@ void tst_QAbstractSlider::setValue() QCOMPARE(slider->sliderPosition(), reportedSliderPosition); if (down) QVERIFY(sliderMovedTimeStamp < valueChangedTimeStamp); + + slider->setValue(50); + QApplication::processEvents(); + QCOMPARE(spy2.size(), 1); } void tst_QAbstractSlider::waitUntilTimeElapsed(const QElapsedTimer &t, int ms)