From 3c26e37e5a93d08320474dc559256c013a0c7564 Mon Sep 17 00:00:00 2001
From: Jere Tuliniemi <jere.tuliniemi@qt.io>
Date: Thu, 9 Oct 2025 12:12:25 +0300
Subject: [PATCH] Disable axis drag handler if not needed
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Pick-to: 6.9
Fixes: QTBUG-135931
Change-Id: Idbc3b9d04fbde1985f0209964d9d1c0a60bb2f2f
Reviewed-by: Sami Varanka <sami.varanka@qt.io>
Reviewed-by: Tomi Korpipää <tomi.korpipaa@qt.io>
(cherry picked from commit 2666c118ccff618ff3584bf3030f19c0ffec7c26)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/graphs2d/qsgrenderer/axisrenderer.cpp | 38 ++++++++++++++++++-----
 src/graphs2d/qsgrenderer/axisrenderer_p.h |  2 ++
 2 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/src/graphs2d/qsgrenderer/axisrenderer.cpp b/src/graphs2d/qsgrenderer/axisrenderer.cpp
index 9164b3e4..1d326586 100644
--- a/src/graphs2d/qsgrenderer/axisrenderer.cpp
+++ b/src/graphs2d/qsgrenderer/axisrenderer.cpp
@@ -57,14 +57,6 @@ AxisRenderer::AxisRenderer(QQuickItem *parent)
 {
     m_graph = qobject_cast<QGraphsView *>(parent);
     setFlag(QQuickItem::ItemHasContents);
-
-    m_dragHandler = new QQuickDragHandler(this);
-    m_dragHandler->setDragThreshold(10);
-    m_dragHandler->setTarget(nullptr);
-    connect(m_dragHandler, &QQuickDragHandler::translationChanged,
-            this, &AxisRenderer::onTranslationChanged);
-    connect(m_dragHandler, &QQuickDragHandler::grabChanged,
-            this, &AxisRenderer::onGrabChanged);
 }
 
 AxisRenderer::~AxisRenderer() {}
@@ -316,6 +308,14 @@ void AxisRenderer::onGrabChanged(QPointingDevice::GrabTransition transition, QEv
 
 void AxisRenderer::handlePolish()
 {
+    if (m_graph->panStyle() != QGraphsView::PanStyle::None
+        || m_graph->zoomStyle() != QGraphsView::ZoomStyle::None || m_graph->zoomAreaEnabled()) {
+        if (!m_dragHandler)
+            createDragHandler();
+    } else if (m_dragHandler) {
+        deleteDragHandler();
+    }
+
     // See if series is horizontal, so axis should also switch places.
     bool vertical = true;
     if (m_graph->orientation() == Qt::Orientation::Horizontal)
@@ -1575,6 +1575,28 @@ void AxisRenderer::updateDateTimeXAxisLabels(AxisProperties &ax, const QRectF re
     }
 }
 
+void AxisRenderer::createDragHandler()
+{
+    m_dragHandler = new QQuickDragHandler(this);
+    m_dragHandler->setDragThreshold(10);
+    m_dragHandler->setTarget(nullptr);
+    connect(m_dragHandler,
+            &QQuickDragHandler::translationChanged,
+            this,
+            &AxisRenderer::onTranslationChanged);
+    connect(m_dragHandler, &QQuickDragHandler::grabChanged, this, &AxisRenderer::onGrabChanged);
+}
+
+void AxisRenderer::deleteDragHandler()
+{
+    disconnect(m_dragHandler,
+               &QQuickDragHandler::translationChanged,
+               this,
+               &AxisRenderer::onTranslationChanged);
+    disconnect(m_dragHandler, &QQuickDragHandler::grabChanged, this, &AxisRenderer::onGrabChanged);
+    m_dragHandler->deleteLater();
+}
+
 // Calculate suitable major step based on range
 double AxisRenderer::getValueStepsFromRange(double range)
 {
diff --git a/src/graphs2d/qsgrenderer/axisrenderer_p.h b/src/graphs2d/qsgrenderer/axisrenderer_p.h
index 87d70ee8..218dc01f 100644
--- a/src/graphs2d/qsgrenderer/axisrenderer_p.h
+++ b/src/graphs2d/qsgrenderer/axisrenderer_p.h
@@ -103,6 +103,8 @@ private:
     void updateDateTimeYAxisLabels(AxisProperties &ax, const QRectF rect);
     void updateDateTimeXAxisLabels(AxisProperties &ax, const QRectF rect);
 
+    void createDragHandler();
+    void deleteDragHandler();
     void onTranslationChanged(QVector2D delta);
     void onGrabChanged(QPointingDevice::GrabTransition transition, QEventPoint point);